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Gaviria-Uribe, Xiomara, Joaquín Castro-Montoya, Diana María Bolívar, Isabel Molina-Botero, Ngonidzashe Chirinda, Uta Dickhoefer, Rolando Barahona i Jacobo Arango. "The Effects of Two Species of Leucaena on In Vitro Rumen Fermentation, Methane Production and Post-ruminal Protein Supply in Diets Based on Urochloa hybrid cv. Cayman". Agronomy 12, nr 3 (4.03.2022): 629. http://dx.doi.org/10.3390/agronomy12030629.
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This study evaluates the effects of the inclusion of two different Leucaena species as a source of condensed tannins based on in vitro fermentation, methane production and post-ruminal protein supply in a diet based on Urochloa hybrid cv. Cayman CIAT BR02/1752 grass. Under in vitro conditions, Leucaena leucocephala CIAT 17263 and Leucaena diversifolia ILRI 15551 were incubated in two proportions (25% and 50% w/w) with Cayman grass and with/without polyethylene glycol as a tannin-binder. The results show that substrates with Leucaena diversifolia produced less gas and methane than those with Leucaena leucocephala with and without polyethylene glycol. The mass in undegraded feed + solid associated microbes fraction decreased linearly with increasing level of inclusion of both species of Leucaena, while increasing its nitrogen content. It is concluded that the condensed tannins of Leucaena diversifolia possess the superior activity and that the tannin content of both evaluated Leucaenas did not affect the diet degradation, and reductions in post-ruminal protein did not occur in the present study. Further studies are needed to differentiate the tannins present in different Leucaena species and their dietary effects.
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Khaing, Myo, Min Aung, Moe Thida Htun, Khin San Mu, Aung Aung i Tin Ngwe. "Effect of leucaena forage and silage substitution in concentrates on digestibility, nitrogen utilization and milk yield in dairy cows". Journal of Applied and Advanced Research 1, nr 3 (12.10.2016): 37. http://dx.doi.org/10.21839/jaar.2016.v1i3.32.
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This experiment was conducted to determine the effect of feeding leucaena forage and silage substitution in concentrate on the performances of dairy cows. Nine cross-bred Holstein Friesian cows (410±12kg) in the 12th week of lactation were randomly allocated to one of three treatment groups with three replicates/treatments in a completely randomized design. The three treatments were control diet without substitution of leucaena forage and silage (DLFS0), diet with substitution of leucaena forage 10% (DLF10) and diet with substitution of leucaena silage 10% (DLS10). Cows were fed treatments for 60 days. Although nutrient intakes were not significantly different (p>0.05) each other, digestibility of DLFS0 was significantly higher (p<0.05) than others. Conversely, nitrogen utilization and average milk yield of cows offered DLFS0 were significantly lower (p<0.05) than those of cows fed on DLF10 and DLS10. The highest feed cost (p<0.05) per kg of milk was found in DLFS0 and the lowest cost was observed in DLF10. Therefore, although the leucana forage and silage could be substitute up to 10% of concentrates without adverse effects on the performances of dairy cows, the substitution of leucaena forage gave the better performances than that of leucaena silage.
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Yanuarianto, Oscar, Muhamad Amin, Sofyan Damrah Hasan, Syamsul Hidayat Dilaga i Suhubdy Suhubdy. "Komposisi Nutrisi dan Kecernaan Silase Jerami Jagung yang Ditambah Lamtoro dan Molases yang Difermentasi pada Waktu Berbeda". Jurnal Ilmu dan Teknologi Peternakan Indonesia (JITPI), Indonesian Journal of Animal Science and Technology 5, nr 2 (17.06.2020): 70. http://dx.doi.org/10.29303/jitpi.v5i2.63.
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The study that aimed to determine the content of crude protein (CP), crude fiber (CF) and in vitro digestibility of dry matter (DM) and organic matter (OM) of corn straw silage added with leucaena and molasses fermented at different times, had been carried out at Nutrition and Feed Laboratory, Faculty of Animal Husbandry, University of Mataram. The corn straw and leucana used in this study were taken from the agricultural area in the Gerung sub-district of West Lombok Regency shortly after harvesting and were cut into pieces with a size of 3-5 cm. This study used a Completely Randomized Design (CRD) consisting of 5 level of treatments, namely: T1: corn straw + leucaena 10% and molasses 5% without fermentation, T2: corn straw + leucaena 10% and molasses 5% fermented 7 days, T3: corn straw + leucaena 10% and molasses 5% fermented 14 days, T4: corn straw + leucaena 10% and molasses 5% fermented 21 days, T5: corn straw + leucaena 10% and molasses 10% fermented 28 days. The variables observed in this study were CP, CF, and in vitro digestibility of DM and OM. Data obtained in this study were analyzed using analysis of variance based on a Completely Randomized Design using the SAS statistical program package and the differences were further tested using the Duncan Test. The results showed that fermentation time could significantly decrease (P <0.05) CF content and increase (P <0.05) CP silage content, but there was no significant increase (P> 0.05) of DM and OM digestibility in vitro of silage fermented for 7, 14, 21 and 28 days.
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Purwantari, Nurhayati D. "FORAGE PRODUCTION OF SOME LESSER-KNOWN LEUCAENA SPECIES GROWN ON ACID SOIL". Indonesian Journal of Agricultural Science 6, nr 2 (25.10.2016): 46. http://dx.doi.org/10.21082/ijas.v6n2.2005.46-51.
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Leucaena leucocephala leaves are nutritious and palatable for ruminants. However, the plant is poorly adapted on acid soil, water logged, and susceptible to psyllid (Heteropsylla cubana). Leucaena favours soils with pH >5. It performs best on calcareous soils. This study aimed to evaluate adaptability of several Leucaena species on acid soils. The study was conducted at the experimental field in Ciawi, Bogor, altitude 500 m above sea level, rainfall 1500-2000 mm year-1, on Latosol soil with pH 5.2. Leucaena species evaluated were L. leucocephala K28, L. leucocephala (local type), Leucaena KX2 hybrid, L. collinsii, L. trichandra, and L. diversifolia. Experiment was designed in a randomized complete block, four replications. All the seedlings were grown in the nursery for 2.5 months before being transplanted to the field. The plants were grown in row plots of 5 m x 1 m with planting distance 0.5 m and spacing between row plot was 3 m. One unit replicate was 5 m x 21 m. In wet season, the plants were pruned at 50 cm height every 3 months, whilst in dry season pruning was done every 5 months. Parameter measured were plant regrowth and forage production (edible part and non-edible part of the plant), as well as N and P content of the edible part. The result showed that Leucaena KX2 hybrid was superior to other leucaenas. Regrowth of KX2 hybrid was the fastest and produced highest forage. The highest fresh weight forage production for 1 year (four times harvests), i.e. 33.93 t ha-1 year-1 equal to 12.48 t ha- 1 year-1 of dry weight, was obtained from Leucaena KX2 hybrid, whereas the lowest was produced by L. diversifolia, i.e. 3.12 t ha-1 year-1 of fresh weight or 1.01 t ha-1 year-1 of dry weight. Production of non-edible part followed the pattern of production of edible part. N and P content in the edible part of all Leucaena species did not show any significant difference except for L. trichandra which contained the lowest. This study implies that Leucaena KX2 hybrid is adaptable to acid soil; therefore it can be grown in wider areas throughout Indonesia.
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Purwantari, Nurhayati D. "FORAGE PRODUCTION OF SOME LESSER-KNOWN LEUCAENA SPECIES GROWN ON ACID SOIL". Indonesian Journal of Agricultural Science 6, nr 2 (25.10.2016): 46. http://dx.doi.org/10.21082/ijas.v6n2.2005.p46-51.
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Leucaena leucocephala leaves are nutritious and palatable for ruminants. However, the plant is poorly adapted on acid soil, water logged, and susceptible to psyllid (Heteropsylla cubana). Leucaena favours soils with pH >5. It performs best on calcareous soils. This study aimed to evaluate adaptability of several Leucaena species on acid soils. The study was conducted at the experimental field in Ciawi, Bogor, altitude 500 m above sea level, rainfall 1500-2000 mm year-1, on Latosol soil with pH 5.2. Leucaena species evaluated were L. leucocephala K28, L. leucocephala (local type), Leucaena KX2 hybrid, L. collinsii, L. trichandra, and L. diversifolia. Experiment was designed in a randomized complete block, four replications. All the seedlings were grown in the nursery for 2.5 months before being transplanted to the field. The plants were grown in row plots of 5 m x 1 m with planting distance 0.5 m and spacing between row plot was 3 m. One unit replicate was 5 m x 21 m. In wet season, the plants were pruned at 50 cm height every 3 months, whilst in dry season pruning was done every 5 months. Parameter measured were plant regrowth and forage production (edible part and non-edible part of the plant), as well as N and P content of the edible part. The result showed that Leucaena KX2 hybrid was superior to other leucaenas. Regrowth of KX2 hybrid was the fastest and produced highest forage. The highest fresh weight forage production for 1 year (four times harvests), i.e. 33.93 t ha-1 year-1 equal to 12.48 t ha- 1 year-1 of dry weight, was obtained from Leucaena KX2 hybrid, whereas the lowest was produced by L. diversifolia, i.e. 3.12 t ha-1 year-1 of fresh weight or 1.01 t ha-1 year-1 of dry weight. Production of non-edible part followed the pattern of production of edible part. N and P content in the edible part of all Leucaena species did not show any significant difference except for L. trichandra which contained the lowest. This study implies that Leucaena KX2 hybrid is adaptable to acid soil; therefore it can be grown in wider areas throughout Indonesia.
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Bouček, Z. "Tamarixia leucaenae sp. n. (Hymenoptera: Eulophidae) parasitic on the leucaena psyllid Heteropsylla cubana Crawford (Hemiptera) in Trinidad". Bulletin of Entomological Research 78, nr 3 (wrzesień 1988): 545–47. http://dx.doi.org/10.1017/s0007485300013298.
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AbstractTamarixia leucaenae sp. n. is described from Trinidad as a parasitoid of Heteropsylla cubana Crawford. The psyllid is a serious pest of Leucaena leucocephala, which is used as a shade tree in plantations of various crops in the tropics.
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YAMOAH, C. F., M. NGUEGUIM i C. NGONG. "STIMULATION OF TOP AND ROOT GROWTH OF LEUCAENA WITH FARM MANURE IN THE MID-ALTITUDE AGRO-ECOLOGICAL ZONE OF NORTH-WEST CAMEROON". Experimental Agriculture 34, nr 3 (lipiec 1998): 313–22. http://dx.doi.org/10.1017/s0014479798343021.
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Leucaena (Leucaena leucocephala) is most preferred by development workers for agroforestry in the mid-altitude (600–1600 m) agro-ecological zone of North-West Cameroon because its seeds are common and inexpensive. This study was prompted by farmers' reluctance to accept leucaena for agroforestry because its early growth is poor on acid infertile soils prevalent in the area. Leucaena was planted using four-month-old potted plants and, from four months after planting, the shrub was cut five times in 20 months at 120 day intervals. Manuring improved leucaena's growth and biomass at sites with acid and non-acid soil alike. Total biomass responded linearly (R2=0.97) to manure rates at the acid and infertile site and curvilinearly (R2=0.95) at the non-acid site. Total leafy biomass from the first cut and subsequent prunings was highest at 12 months after planting. Manuring increased rooting depth and this contributed to the plant's observed ability to cope with moisture stress during the dry season. The economics of manure use for tree establishment on acid infertile soils for agroforestry systems needs further study.
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Cooksley, DG, i EA Goward. "Effect of plant density and spatial arrangement on the yield of Leucaena leucocephala cv. Peru in subcoastal south-eastern Queensland". Australian Journal of Experimental Agriculture 28, nr 5 (1988): 577. http://dx.doi.org/10.1071/ea9880577.
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Leucaena (Leucaena leucocephala cv. Peru) was sown at 5 plant densities with 2 spatial arrangements at Brian Pastures Pasture Research Station, Gayndah, to determine the effects of these factors on leucaena and inter-row grass dry matter yield. During the 2 year establishment phase, yields of edible leucaena (leaves, pods, flowers and stems to a diameter of 5 mm) averaged 4400 and 2440 kg/ha respectively. Yields in subsequent years stabilised to an overall mean of 1360 kg/ha, with the amount of edible leucaena increasing with increasing leucaena plant density from 640 to 2260 kg/ha at 6000 and 62 500 leucaena plants/ha respectively. Edible leucaena yield for the mean of the 5 plant densities was increased by 38% when row spacing was doubled. Yields of both total and senesced leucaena were directly related to the annual rainfall. At the end of each growing season in May, edible leucaena yield remained stable between rainfall extremes of 492 and 878 mm while the amount of senesced leucaena litter increased. Edible leucaena yield was directly related to leucaena plant density (R2= 0.86). Annual total leucaena yield (edible leucaena yield plus leucaena litter) was best related to the plant parameters leucaena plant volume (R2 = 0.92), leucaena stem numbers (R2 = 0.90) and leucaena stem diameter (R2 = 0.90). Number of green panic (Panicum maximum var, trichoglume) shoots showed a marked increase at the 3 higher leucaena densities (mean of 28 shoots/m2) compared with the 2 lower leucaena densities (mean of 7 shoots/m2). Total soil nitrogen also increased at the 3 higher leucaena densities (mean of 0.186%) relative to the 2 lower leucaena densities (mean of 0.170%). Inter-row grass and grass litter yields both declined from 4640 and 4010 kg/ha to 31 10 and 2420 kg/ha respectively with increasing leucaena density. Maximum yields of edible leucaena were obtained when leucaena was grown at a density of 62 500 plants per ha in rows 0.8 m apart.
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Shivas, R. G., T. Triglone i S. Petty. "First record of Cercosporella leucaenae on Leucaena leucocephala in Australia". Australasian Plant Pathology 25, nr 1 (1996): 24. http://dx.doi.org/10.1071/ap96005.
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Pachas, A. Nahuel A., H. Max Shelton, Christopher J. Lambrides, Scott A. Dalzell, G. John Murtagh i Craig M. Hardner. "Effect of tree density on competition between Leucaena leucocephala and Chloris gayana using a Nelder Wheel trial. II. Belowground interactions". Crop and Pasture Science 69, nr 7 (2018): 733. http://dx.doi.org/10.1071/cp18040.
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Leucaena (Leucaena leucocephala (Lam.) de Wit subsp. glabrata (Rose) Zarate) in combination with grass pasture is one of the most persistent, productive and sustainable grazing systems used in Queensland, Australia. Nevertheless, a better understanding of the competitive interactions that determine the proportions of leucaena and grass components is needed to optimise the design and management of the hedgerow pasture system. In a water-limited environment, belowground interactions between species are especially influential. Accordingly, the aim of this study was to determine the effect of leucaena plant density and Rhodes grass (Chloris gayana Kunth) competition on root distribution, evapotranspiration, patterns of soil-water use and the resulting water-use efficiency (WUE) of the leucaena and grass components. Results showed that although leucaena had deeper roots than Rhodes grass, the majority of fine roots of both leucaena and Rhodes grass were in the upper 1.5 m of the soil profile suggesting a high level of competition for water resources. A major factor favouring Rhodes grass was that its root abundance was 8–10 times greater than leucaena, allowing it to compete more effectively for water resources and limit the lateral spread of leucaena roots. Higher cumulative evapotranspiration values were recorded from leucaena grown with Rhodes grass than from leucaena grown in absence of grass. However, this difference was negligible at the highest leucaena density owing to the reduced yield of grass caused by shading and increased water uptake of leucaena. The findings of this study also confirmed the hypothesis that at low tree densities, leucaena–grass pasture will have higher WUE (13.8 kg DM mm–1) than sole leucaena, but this difference was reduced with increments of leucaena density. Highest WUE (65.9 kg DM mm–1) occurred at highest leucaena density with or without grass.
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Irawan, Fahrul, Dahlanuddin, Michael J. Halliday, Roger S. Hegarty i Frances C. Cowley. "The role of leucaena in cattle fattening and breeding production systems in Eastern Indonesia". Tropical Grasslands-Forrajes Tropicales 10, nr 3 (30.09.2022): 222–36. http://dx.doi.org/10.17138/tgft(10)222-236.
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Cattle farming in West Nusa Tenggara province, Indonesia (NTB) is essential to support the high demand for beef cattle in Indonesia. Leucaena was introduced to smallholders as a high-quality feed to increase cattle production in NTB. A survey was conducted with both leucaena-using and non-leucaena-using smallholder cattle farmers in Sumbawa and West Sumbawa districts, NTB to understand the role of leucaena in NTB smallholder cattle enterprises (mixed breeding/fattening) and the effect of leucaena toxicity on cattle performance, especially cow-calf production. We found that farmers using leucaena feeding systems were able to keep more cattle than farmers using a traditional feeding system (9.1 vs 6.1 head/household). Many leucaena-using farmers (50.1 %) use leucaena for fattening cattle only. Other cattle classes (growers, breeding cows and bulls) were fed leucaena strategically, such as during the dry season (59 % of leucaena-using farmers) and at specific stages of pregnancy and lactation (41 % of leucaena-using farmers). Leucaenausing farmers in rainfed areas planted more leucaena (4,500 vs 1,984 trees) and fattened more bulls (5.8 vs 3.5 head/ household) than farmers in high-rainfall areas. Transmigrant Balinese farmers planted significantly more leucaena trees (7,500 vs 2,354 trees) and raised more fattening bulls (7.8 vs 3.7 head/household) than the local Sumbawanese farmers. Most Balinese farmers had been practising leucaena feeding systems since they migrated to Sumbawa, for a long as 3 decades. Most leucaena-using farmers (74 %) had observed symptoms of illness associated with leucaena toxicity in their cattle such as hair loss and salivation. Few farmers feeding leucaena to breeding cows (5 %) reported instances of reproductive failure. Almost all non-leucaena-using farmers (93 %) reported symptoms of illnesses associated with plant toxicities (among other potential causes), most commonly skin lesions, diarrhoea, cataract, and listlessness. It was concluded that the priority use of leucaena in Sumbawa was for fattening cattle rather than breeding cattle. Leucaena supports smallholder farmers in Sumbawa to have more intensive, productive and income-earning cattle enterprises, but questions remain over whether it should be used for feeding breeding cows.
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Taylor, Chris A., Matthew T. Harrison, Marnie Telfer i Richard Eckard. "Modelled greenhouse gas emissions from beef cattle grazing irrigated leucaena in northern Australia". Animal Production Science 56, nr 3 (2016): 594. http://dx.doi.org/10.1071/an15575.
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Agriculture produces an estimated 14.5% of global anthropogenic greenhouse gases, with livestock emissions being the largest source of enteric methane. Reducing greenhouse gas (GHG) emissions from production and processing of beef cattle will become increasingly important with time, particularly in line with global efforts to mitigate rising GHG emissions. The present study compared several GHG emission scenarios from beef cattle grazing on irrigated Leucaena leucocephala (Lam.) de Wit cv. Cunningham (leucaena) in Queensland, Australia. Animals began grazing the leucaena paddocks when they were 16 months old and continued until ~240 days, before being sold to market. Three scenarios were modelled with cattle grazing leucaena and the resulting GHG emissions calculated, representing (1) the current leucaena paddock (current leucaena scenario), (2) clearing native vegetation and extending the leucaena paddock (extended leucaena scenario) and (3) extending the leucaena paddock onto previously cleared paddocks (alternative leucaena scenario). These were compared with a pre-scenario baseline, where the steers grazed on native vegetation until the time of sale. Herd GHG emission intensities (EI) were reduced in comparison with the baseline (EI of 8.4 tCO2-e/t liveweight sold) for all the leucaena scenarios, where reductions were modelled for the current, extended and alternative leucaena scenarios, which had an EI of 3.9, 3.7 and 3.6 tCO2-e/ t liveweight sold, respectively. Reductions were attributed to the higher growth rates of the steers on leucaena and the anti-methanogenic potential of leucaena. Where leucaena was planted on previously cleared paddocks, carbon stocks (t C/ha) nearly doubled a decade following planting, with most carbon sequestered in the soil. However, total carbon stocks on the property reduced over the modelled period (112 years), where native vegetation, e.g. eucalyptus woodland, was cleared for leucaena planting, but soil carbon yield increased. The combined sequestration of leucaena and the reduction of GHG emission intensities resulted in overall net reductions of GHG emissions for the three leucaena scenarios compared with the baseline. These results demonstrated that the use of leucaena for grazing can be an effective means for farmers to reduce the GHG emissions and increase productivity of their herds. The study also demonstrated that it would take 9 years of reduced emissions to compensate for the carbon lost as emissions from clearing the eucalyptus woodland, suggesting that farmers should use other methods of intensifying production from existing leucaena paddocks if their sole purpose is short-term emissions abatement.
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Quirk, MF, CJ Paton i JJ Bushell. "Increasing the amount of leucaena on offer gives faster growth rates of grazing cattle in South East Queensland". Australian Journal of Experimental Agriculture 30, nr 1 (1990): 51. http://dx.doi.org/10.1071/ea9900051.
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We measured the effect of increased supply of leucaena (Leucaena leucocephala cv. Peru) on the growth of steers grazing native pasture in South East Queensland. Steers grazed paddocks of black speargrass (Heteropogon contortus) pasture in which either 0, 25 or 100% of the area was sown to 3 m-wide rows of leucaena. In the 25% leucaena treatment, the leucaena portion was ungrazed in summer. Mimosine toxicity was avoided by dosing cattle with mimosine-detoxifying rumen bacteria. The growth rate of steers increased with the proportion of the paddock covered by leucaena. Steers grazing paddocks with 0, 25, and 100% of the paddock covered by leucaena rows gained 90, 127 and 205 kg/steer.year, respectively. The amount of leucaena foliage on offer appeared to be the major factor increasing steer growth.
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Radrizzani, A., S. A. Dalzell, O. Kravchuk i H. M. Shelton. "A grazier survey of the long-term productivity of leucaena (Leucaena leucocephala)-grass pastures in Queensland". Animal Production Science 50, nr 2 (2010): 105. http://dx.doi.org/10.1071/an09040.
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Leucaena leucocephala subsp. glabrata (leucaena)-grass pastures are productive, perennial and long-lived (>40 years). However, little is known about changes in the productivity of these pastures as they age even though they are grazed intensively and are rarely fertilised. A postal survey of beef cattle producers in Queensland who grow leucaena pastures was conducted. The questionnaire gathered information regarding: property location; extent and age of leucaena pastures; soil type; leucaena and grass establishment methodology; grazing and fertiliser management; and grazier perceptions of changes over time in leucaena productivity, grass growth and ground cover, prevalence of undesirable grasses and weeds, and livestock productivity. Graziers were asked to report on both young (≤10 years old) and aging (>10 years old) pastures under their management. Eighty-eight graziers responded describing 124 leucaena paddocks covering 11 750 ha. The survey results described the typical physical and management characteristics of leucaena pastures in Queensland. Graziers reported a decline in leucaena productivity in 58% of aging pastures, and declines in grass growth (32%) and livestock productivity (42%) associated with declining leucaena growth. Leucaena decline was greater in soil types of marginal initial fertility, particularly brigalow clay, soft wood scrub, downs and duplex soils. Maintenance fertiliser was not applied to most (98%) leucaena pastures surveyed despite significant amounts of nutrient removal, particularly phosphorus and sulphur, occurring over prolonged periods of moderate to high grazing pressure. It is predicted that large areas of leucaena pasture will continue to suffer soil nutrient depletion under current management practices. Research is needed to develop ameliorative actions to reinvigorate pasture productivity.
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Putra, Achmad Noerkhaerin, Anngy Chahya Pradana, Deny Novriansyah i Mustahal Mustahal. "EFFECT OF DIETARY FERMENTED LAMTORO (Leucaena leucocephala) LEAVES FLOUR IN FEED ON DIGESTIBILITY AND HEMATOLOGICAL PARAMETERS OF CATFISH (Clarias sp.)". e-Jurnal Rekayasa dan Teknologi Budidaya Perairan 8, nr 1 (24.10.2019): 951. http://dx.doi.org/10.23960/jrtbp.v8i1.p951-964.
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Leucaena leaves is a potential ingredient for raw material feed of catfish. The aim of this study is to evaluate the effects of dietary fermented leucaena leaf on digestibility and hematological parameters of catfish. Four treatments and 3 replicates, namely: A (reference feed 70% + leucaena leaves meal 30%), B (reference feed 70%+fermented leucaena leaves meal with A. niger 30%), C (reference feed 70%+fermented leucaena leaves meal with R. oligosporus 30%), and feed D (reference feed 70%+fermented leucaena leaves meal with S. cerevisiae 30%) were used in this study. The juvenile catfish (initial weight was 5,45±0,16 g) are randomly distributed into eighteen tanks with 40 fish per aquarium. Each diet is randomly assigned to the triplicate aquarium and fed to fish three times a day up to satiation for 4 weeks. The results showed that fermented leucaena leaves treatments were significantly higher (P<0.05) than that control in final weight and feed conversion rasio. Nutrients digestibility and final weight were significantly highest (P<0.05) in fermented leucaena leaves with A. niger compared to the other treatment. The value of protein digestibility was significantly highest (P<0.05) in fermented leucaena leaves with A. niger (76,04%), followed by fermented leucaena leaves S. cerevisiae with (69,71%), fermented leucaena leaves meal with R. oligosporus (68,24%), and control (65,18). Leucaena leaves had no effect on physiological processes in catfish, as shown by hematological parameter values that were within the normal range.
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Radrizzani, Alejandro, Nahuel A. Pachas, Luis Gándara, Fernando Nenning i Dante Pueyo. "Leucaena feeding systems in Argentina. II. Current uses and future research priorities". Tropical Grasslands-Forrajes Tropicales 7, nr 4 (3.09.2019): 389–96. http://dx.doi.org/10.17138/tgft(7)389-396.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.This paper presents the current status of Leucaena leucocephala (leucaena) feeding systems and proposes research priorities for leucaena development in Argentina. Although research on leucaena as forage for cattle production began in the late 1960s, it was not widely adopted until 2010 (5 decades later). The recent adoption is related to the incorporation of the ‘Australian technology package’, previously adapted for use by farmers in the neighboring region of the Paraguayan Chaco. In June 2018, we surveyed 8 properties with about 2,400 ha of leucaena in silvopastoral systems for beef cattle production in the Argentinean Chaco region, as well as 10 smallholder farms with about 10 ha of leucaena protein banks for dairy cattle in the northeast of Argentina. In the silvopastoral systems, leucaena condition was excellent on most properties in the 750‒1,350 mm/year rainfall zone and low/poor on only 1 farm due to low rainfall (600 mm/year). In protein banks, leucaena condition was excellent or good on 6 of the properties and low/poor on the remaining 4, attributed to ingress of weeds and/or overgrazing. Grass condition was good in most of the systems but was low/poor in 2 silvopastoral systems due to very high stocking rates imposed to restrict leucaena height. Although there is high potential for leucaena development in Argentina, expansion should take place carefully with leucaena planted only on areas suitable for successful establishment, and using appropriate management practices to reduce establishment failures and costs, restrict leucaena height, enhance grass persistence, improve grazing strategies and manage mimosine toxicity problems.
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Honda, Michael D. H., i Dulal Borthakur. "Mimosine concentration in Leucaena leucocephala under various environmental conditions". Tropical Grasslands-Forrajes Tropicales 7, nr 2 (31.05.2019): 164–72. http://dx.doi.org/10.17138/tgft(7)164-172.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.Leucaena leucocephala (leucaena) is a multipurpose tropical tree-legume that is highly resistant to many biotic and abiotic stresses. Leucaena is used primarily as an animal fodder owing to its protein-rich foliage. However, leucaena foliage also contains mimosine, a toxic non-protein amino acid that can cause alopecia, goiter and other thyroid problems, infertility, and fetal death. Considering its toxicity and abundance in leucaena, it is important to quantify the mimosine concentrations in leucaena under different environmental conditions. Mimosine was extracted from various types of leucaena tissue exposed to a range of environmental conditions and then quantified by HPLC. The mimosine concentrations in leucaena treated with NaCl increased after 6 days of treatment and remained relatively high when treatment continued for 18 days. Interestingly, leucaena exposed to complete darkness for up to 5 days had a higher mimosine concentration than control plants exposed to normal light/dark photoperiods. On the other hand, drying leucaena leaflets or macerating them in an alkaline buffer significantly lowered their mimosine concentration. Mature leaflets that had fallen off the plant and dried out also contained significantly less mimosine than fresh leaflets. The results of this study indicate that mimosine concentrations in leucaena are affected by environmental conditions and this knowledge can assist in managing to prevent toxicity.
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Jeanes, K. W., R. C. Gutteridge i H. M. Shelton. "Competition Effects between Leucaena and Maize Grown Simultaneously in an Alley Cropping System in Sub-tropical Australia". Experimental Agriculture 32, nr 1 (styczeń 1996): 49–56. http://dx.doi.org/10.1017/s0014479700025849.
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SUMMARYA field experiment was conducted to assess the effect of competition between a leucaena hybrid and maize (Zea mays L.) when planted simultaneously in an alley cropping system. The leucaena hybrid (a cross between L. diversifolia and L. leucocephala) was planted at hedgerow spacings of 3 and 5.25 m, while maize was planted in rows 75 cm apart between the hedgerows. The spacing between the leucaena hedgerow and maize was varied by removal of 0, l or 2 rows of maize to give three spacing treatments of 37.5, 75 or 112.5 cm between leucaena and maize. A control plot of leucaena alone was also included in the treatments. The growth and yield of individual maize rows were virtually unaffected by the presence of leucaena, but maize had a significant influence on the growth and yield of leucaena. At full maize canopy development, photosynthetically active radiation reaching the leucaena was reduced in all treatments, resulting in a 75% yield reduction in leucaena at the closest spacing. Overall, maize grain yield reached 10.3 t ha−1 in the continuous maize plots (37.5 cm treatment). This was reduced by up to 40% after removal of two maize rows in the closest leucaena row spacing treatment. The implications of these results for the practical establishment of leucaena hedgerows with a maize crop are discussed.
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Aung, A. "Leucaena feeding systems in Myanmar". Tropical Grasslands-Forrajes Tropicales 7, nr 4 (3.09.2019): 423–27. http://dx.doi.org/10.17138/tgft(7)423-427.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.Agriculture and livestock provide the main source of income for farmers in Myanmar. As feeds with low nutritive value and digestibility are traditionally used for animal feed, alternative feed sources of better quality are needed to improve production levels. While concentrates can be used to improve the quality of diets, this leads to high feed costs. To solve this problem, researchers in Myanmar conducted trials to replace some concentrates with leucaena. The nutritive value of leucaena in Myanmar is relatively the same as found in other countries. Control of leucaena toxicity was also studied in Myanmar by isolating mimosine-degrading bacteria and managing the feeding of leucaena. While farmers in Myanmar are aware that leucaena can be fed to livestock and can be toxic to animals, they have limited knowledge of the real benefits of leucaena as a feed for animals. Research to demonstrate the potential of leucaena feeding to animals in Myanmar and efforts to promote establishment of leucaena stands are urgently needed.
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Beutel, Terrence S., Debra H. Corbet, Madonna B. Hoffmann, Stuart R. Buck i Marco Kienzle. "Quantifying leucaena cultivation extent on grazing land". Rangeland Journal 40, nr 1 (2018): 31. http://dx.doi.org/10.1071/rj17085.
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Leucaena is a perennial fodder crop that can significantly improve beef production across substantial parts of the world’s grazing lands. We surveyed leucaena cultivations across 350 000 km2 of Australia’s prime leucaena-growing region, using a new approach to quantify leucaena coverage and distribution. This approach uses high resolution imagery to detect leucaena by the distinctive alley cultivation pattern that is typical in the region and in many other parts of the world. We estimated there are ~123 500 ha of leucaena in the study region. Although no prior estimate of leucaena coverage has been based on exactly the same geographic area, our data strongly suggest that recent published estimates of leucaena coverage for Queensland and Australia are substantial overestimates. In addition to providing robust estimates of total leucaena coverage, we demonstrate how the method can also contribute to other survey objectives such as comparison of actual with potential spatial distribution, and assessment of statistical sampling power. We also discuss the potential application of the new method in international contexts.
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Ribeiro, Renan Augusto, Marco A. Rogel, Aline López-López, Ernesto Ormeño-Orrillo, Fernando Gomes Barcellos, Julio Martínez, Fabiano Lopes Thompson, Esperanza Martínez-Romero i Mariangela Hungria. "Reclassification of Rhizobium tropici type A strains as Rhizobium leucaenae sp. nov." International Journal of Systematic and Evolutionary Microbiology 62, Pt_5 (1.05.2012): 1179–84. http://dx.doi.org/10.1099/ijs.0.032912-0.
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Rhizobium tropici is a well-studied legume symbiont characterized by high genetic stability of the symbiotic plasmid and tolerance to tropical environmental stresses such as high temperature and low soil pH. However, high phenetic and genetic variabilities among R. tropici strains have been largely reported, with two subgroups, designated type A and B, already defined within the species. A polyphasic study comprising multilocus sequence analysis, phenotypic and genotypic characterizations, including DNA–DNA hybridization, strongly supported the reclassification of R. tropici type A strains as a novel species. Type A strains formed a well-differentiated clade that grouped with R. tropici , Rhizobium multihospitium , Rhizobium miluonense , Rhizobium lusitanum and Rhizobium rhizogenes in the phylogenies of the 16S rRNA, recA, gltA, rpoA, glnII and rpoB genes. Several phenotypic traits differentiated type A strains from all related taxa. The novel species, for which the name Rhizobium leucaenae sp. nov. is proposed, is a broad host range rhizobium being able to establish effective root-nodule symbioses with Leucaena leucocephala, Leucaena esculenta, common beans (Phaseolus vulgaris) and Gliricidia sepium. Strain CFN 299T ( = USDA 9039T = LMG 9517T = CECT 4844T = JCM 21088T = IAM 14230T = SEMIA 4083T = CENA 183T = UMR1026T = CNPSo 141T) is designated the type strain of Rhizobium leucaenae sp. nov.
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Pachas, A. Nahuel A., H. Max Shelton, Christopher J. Lambrides, Scott A. Dalzell i G. John Murtagh. "Effect of tree density on competition between Leucaena leucocephala and Chloris gayana using a Nelder Wheel trial. I. Aboveground interactions". Crop and Pasture Science 69, nr 4 (2018): 419. http://dx.doi.org/10.1071/cp17311.
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Silvopastoral systems with the tree legume leucaena (Leucaena leucocephala (Lam.) de Wit) and grass pastures are widely used for ruminant feeding in subtropical and tropical regions. Different densities and planting configurations of leucaena will influence relative yields of both species because of intra- and interspecific competition. With the aim to describe the effects of competition between leucaena and Rhodes grass (Chloris gayana Kunth), a Nelder Wheel trial with 10 different leucaena tree densities (100–80 000 trees ha–1) growing with and without Rhodes grass was established in a subtropical environment at Gatton, south-east Queensland, in November 2013. From 2014 to 2016, the biomass of leucaena (six harvests) and Rhodes grass (seven harvests) was measured by using allometric equations and the BOTANAL sampling procedure over 742 and 721 days, respectively. No complementary or facilitative aboveground interactions were observed between the leucaena and Rhodes grass components of the pasture system. Increasing leucaena tree density resulted in greater aboveground intra- and interspecific competition. Average maximum individual tree yield (38.9 kg DM tree–1 year–1) was reached at 100 trees ha–1 without grass competition and was reduced by 60% with grass competition. Rhodes grass biomass yield was negatively affected by shading from the leucaena canopy, with negligible grass yield at tree densities ≥8618 trees ha–1. Therefore, there was effectively no grass competition on individual tree yield at higher leucaena densities. Accordingly, edible leucaena biomass per unit area was positively related to log10 leucaena density (R2 = 0.99) regardless of grass competition, reaching 21.7 t DM ha–1 year–1 (2014–15) and 27 t DM ha–1 year–1 (2015–16) at the highest leucaena density of 80 000 trees ha–1. By contrast, the yield of Rhodes grass was linearly and inversely correlated with log10 tree density (R2 = 0.99). Practical implications for the design and management of commercial leucaena–grass pastures are discussed.
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Hopkins, Kyle, Maree Bowen, Rob Dixon i David Reid. "Evaluating crude protein concentration of leucaena forage and the dietary legume content selected by cattle grazing leucaena and C4 grasses in northern Australia". Tropical Grasslands-Forrajes Tropicales 7, nr 2 (31.05.2019): 189–92. http://dx.doi.org/10.17138/tgft(7)189-192.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.In Australia’s central and southern Queensland regions, Leucaena leucocephala-grass pastures produce substantially more beef and higher profits than grass-only pastures and annual forage crops. Near infrared reflectance spectroscopy (NIRS) provides a rapid and cost-effective approach to assessing quality of available forage as well as the quality of the diet selected by cattle, but existing calibrations have not been comprehensively validated for leucaena-grass pastures. This study examined the reliability of existing northern Australian calibrations for NIRS to predict the crude protein (CP) concentration of the edible fraction of the leucaena plant, and the proportion of leucaena in the diet of grazing cattle. Samples of edible leucaena and cattle faeces were analyzed by NIRS and the predictions plotted in a linear regression and fitted to a 1:1 line with Dumas analysis of CP for leucaena forage, and mass spectrometry of δ13C for cattle faeces. Results demonstrated that prediction of the CP concentration of leucaena forage and the proportion of leucaena in the diet of grazing cattle using current broad northern Australian NIRS forage calibrations were associated with substantial error. However, it is likely that these errors can be reduced with the inclusion in the calibration data set of more samples representing leucaena forage and faeces of cattle grazing leucaena from varying locations, seasonal conditions and management strategies.
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Yulistiani, Dwi, Z. A. Jelan i J. B. Liang. "In Vitro protein digestibility and fermentability of mulberry (Morus alba)-Leucaena foliage mixed feed". Jurnal Ilmu Ternak dan Veteriner 21, nr 1 (31.03.2016): 9. http://dx.doi.org/10.14334/jitv.v21i1.1352.
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<p class="abstrak2">This experiment was carried out to determine the effect of mulberry-leucaena foliage mixed feed on protein digestibility and VFA production using an in vitro gas production study. Mulberry was mixed with one of 2 leucaena varieties (<em>Leucaena leucocephala</em> hybrid and <em>Leucaena leucocephala</em> local) at 3 levels (0, 25 and 50%). Study was conducted in completely randomized design. Mulberry foliage, leucaena and mixtures of mulberry-leucaena were incubated for 24 hours in glass syringes. Parameter recorded were gas production, in vitro true dry matter digestibility (IVTDMD), in vitro N digestibility (IVND) and VFA production. Results of the study showed that supplementation of leucaena to mulberry decreased IVOMD, gas production and protein digestibility in the rumen buffered medium. The mixture of mulberry and leucaena hybrid at ratio 50% resulted in the lowest IVND than other treatment. However it increased protein digestibility in acid pepsin incubation as an estimate of protein availability in intestine. Gas production decreased in mulberry leucaena mixtures was followed by decreased total VFA production. Tannin derived from leucaena hybrid supplementation to mulberry at ratio 1 : 1 was most effective to decrease protein digestion in the rumen and to increase protein digestibility in acid pepsin incubation. In conclusion mixing of hybrid leucaena hybrid with mulberry foliage was able to protect protein degradation from mulberry in the rumen.</p>
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Christensen, Bron. "The Leucaena Network and The Leucaena Code of Practice". Tropical Grasslands-Forrajes Tropicales 7, nr 4 (3.09.2019): 331–32. http://dx.doi.org/10.17138/tgft(7)331-332.
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Bickel, A. F., i J. P. Wibaut. "On the structure of leucaenine (leucaenol) from leucaena glauca bentham". Recueil des Travaux Chimiques des Pays-Bas 65, nr 1 (3.09.2010): 65–83. http://dx.doi.org/10.1002/recl.19460650111.
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Brandon, N. J., i H. M. Shelton. "Factors affecting the early growth of Leucaena leucocephala". Australian Journal of Experimental Agriculture 37, nr 1 (1997): 45. http://dx.doi.org/10.1071/ea96010.
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Summary. Previous work has shown that slow colonisation of roots by arbuscular mycorrhizal (AM) fungi may be responsible for the slow early seedling growth of leucaena in some soils. The aim of the following experiments was to determine relative population levels of AM fungi in a range of Australian soils and their effect on the growth and phosphorus nutrition of the tropical tree legume leucaena (Leucaena leucocephala), grown in pots and in the field. Soils chosen were typical of those used for leucaena production in Queensland and included sites at which previous commercial plantings of leucaena had failed. Large differences were found in mycorrhizal population levels between soils and results of a bioassay ranged from 12 to 52% of leucaena root length infected. Results of the bioassay were significantly correlated with plant height of leucaena grown in pots at 28 and 42 days after sowing (P<0.05) and shoot weight 42 days after sowing (P<0.05). However, results of the bioassay were not positively correlated with plant growth of leucaena 63 days after sowing in pots or at any time in the field. This was because colonisation levels in most soils had reached levels that were adequate to meet the phosphorus requirements of the plant. Low population levels of AM fungi, therefore, do not appear to be a major long-term limitation to growth of leucaena in most soils. However, at 2 sites where previous commercial leucaena plantings had failed, other factors became relatively more important in limiting first season yield. These included poor soil physical structure, low phosphorus fertility and at 1 site, colonisation of leucaena roots with root knot nematode, a factor which had not previously been reported in Australia. Soil physical, chemical and biological factors, therefore, all need to be considered in selecting suitable sites for leucaena establishment.
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Cowley, Frances C., i Romana Roschinsky. "Incorporating leucaena into goat production systems". Tropical Grasslands-Forrajes Tropicales 7, nr 2 (31.05.2019): 173–81. http://dx.doi.org/10.17138/tgft(7)173-181.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.The integration of leucaena into goat production systems in the tropics and subtropics is reviewed. Goats are well adapted to leucaena, and able to be productive on diets containing up to 100% leucaena as a result of bacterial and hepatic detoxification. Incorporation of leucaena into goat production systems can improve liveweight gains, milk production, worm control and reproduction. Successful feeding systems for goats can be based on both grazed silvopastoral systems and cut-and-carry intensive systems, although there is a lack of farming systems research examining the integration of leucaena into goat production systems, or documentation of the practicalities of these practices.
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Cortez Egremy, Juan Gerardo, Miguel Uribe Gómez, Artemio Cruz León, Alejandro Lara Bueno i José Luis Romo Lozano. "Árboles nativos para el diseño de tecnologías silvopastoriles en la Sierra de Huautla, Morelos". Revista Mexicana de Ciencias Agrícolas, nr 16 (20.10.2017): 3371. http://dx.doi.org/10.29312/remexca.v0i16.402.
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La deforestación es una práctica que contribuye al deterioro ambiental. Con el propósito de evaluar el potencial forrajero de especies arbóreas de la Sierra de Huautla, Morelos, se aplicó una encuesta para rescatar el conocimiento tradicional en el uso de árboles y arbustos locales. La encuesta se aplicó a dieciocho productores de los ejidos El Limón y Los Sauces del Minicipio de Tepalcingo, Morelos. Los informantes identificaron diez especies arbóreas nativas con potencial forrajero: Guazuma ulmifolia, Acacia cochliacanta, Leucaena leucocephala, Leucaena macrophylla, Leucaena esculenta, Spondias mombin, Spondias purpurea, Erythrina americana, Pithecellobium dulce, y Gliricidia sepium. Guazuma ulmifolia, Acacia cochliacanta, Leucaena leucocephala, Leucaena macrophylla y Leucaena esculenta, las cuales tuvieron alta frecuencia en la encuesta aplicada a los productores. La germinación de semillas de Leucaena esculenta, Guazuma ulmifolia y Acacia cochliacantha, fue superior a 60%. El contenido de proteína en el follaje de Leucaena macrophylla fue superior en 18% y 30% al contenido de proteína de Guazuma ulmifolia y Leucaena leucocephala. La información agronómica reportada en literatura y la generada durante la investigación, permiten recomendar un manejo adecuado de las especies arbóreas mediante el diseño de tecnologías silvopastoriles para mejorar la producción de forraje para el ganado y para minimizar los impactos negativos de la ganadería sobre los recursos naturales.
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Tomkins, Nigel, Matthew Harrison, Chris S. McSweeney, Stuart Denman, Ed Charmley, Cristopher J. Lambrides i Ram Dalal. "Greenhouse gas implications of leucaena-based pastures. Can we develop an emissions reduction methodology for the beef industry?" Tropical Grasslands-Forrajes Tropicales 7, nr 4 (3.09.2019): 267–72. http://dx.doi.org/10.17138/tgft(7)267-272.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.The perennial legume leucaena (Leucaena leucocephala) is grown across the subtropics for a variety of purposes including livestock fodder. Livestock in Australia emit a significant proportion of the methane produced by the agriculture sector and there is increasing pressure to decrease emissions from beef cattle production systems. In addition to direct productivity gains for livestock, leucaena has been shown to lower enteric methane production, suggesting an opportunity for emissions mitigation and Commonwealth Emissions Reduction Fund (ERF) methodology development, where leucaena browse is adopted for high value beef production. Determining the proportion of leucaena in the diet may be one of the more challenging aspects in attributing mitigation. Current enteric emission relationships for cattle consuming mixed grass-leucaena diets are based on intensive respiration chamber work. Herd-scale methane flux has also been determined using open path laser methodologies and may be used to validate an on-farm herd-scale methodology for leucaena feeding systems. The methodology should also address increased potential for soil organic carbon storage by leucaena grazing systems, and changes in nitrous oxide production. This paper outlines the background, justification, eligibility requirements and potential gaps in research for an emissions quantification protocol that will lead to the adoption of a leucaena methodology by the Australian beef industry. Development of a methodology would be supported by research conducted in Australia.
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Zakariyya, Fakhrusy, i Adi Prawoto. "Stomatal Conductance and Chlorophyll Characteristics and Their Relationship with Yield of Some Cocoa Clones Under Tectona grandis, Leucaena sp., and Cassia surattensis." Pelita Perkebunan (a Coffee and Cocoa Research Journal) 31, nr 2 (31.08.2015): 99–108. http://dx.doi.org/10.22302/iccri.jur.pelitaperkebunan.v31i2.165.
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An optimum physiological condition will support high yield and quality of cocoa production. The research was aimed to study the effects of stomatal conductance and chlorophyll content related to cocoa production under three shade regimes.This research was conducted in Kaliwining Experimental Station, elevation of 45 m above sea level with D climate type based on Schmidt & Fergusson. Cocoa trees which were planted in 1994 at a spacing of 3 X 3 m were used in the study planted by using split plot design. The shade tree species were teak (Tectona grandis), krete (Cassiasurattensis), and lamtoro (Leucaena sp.) as the main plots, and cocoa clones of Sulawesi 01,Sulawesi 02, KKM 22 and KW 165 as sub plots. This study showed that there was interaction between cocoa clone and shade species for stomatal conductance where stomatal diffusive resistance of KKM 22 was the best under Leucaena sp.and Cassiasurattensis with the values of 1.38 and 1.34 s.cm -1, respectively. The highest chlorophyll content, stomatal index and transpiration values was under Leucaena sp. shade. There was positive correlation between chlorophyll content and transpiration with pod yield of cocoa. The highest yield and the lowest bean count wereobtainedon Sulawesi 01 clone under Leucaenasp. shade.Keywords: stomatal conductance, transpiration, diffusive resistance, shades trees, clones,pod yield
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Karda, I. W., i G. McL Dryden. "Effect of leucaena supplementation level, and provision of urea, on utilisation by sheep of Rhodes grass hay". Australian Journal of Experimental Agriculture 41, nr 2 (2001): 155. http://dx.doi.org/10.1071/ea99044.
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Tarramba leucaena (Leucaena leucocephala cv. Tarramba) foliage had per kilogram dry matter, 169 g protein and 29.8 g condensed tannins. Its value as a supplement, given either with or without urea, to sheep given a low-quality Callide Rhodes grass (Chloris gayana cv. Callide) hay was studied. Six rumen fistulated sheep (mean s.d. liveweight, 34 1.4 kg) were used to compare 6 dietary treatments in an incomplete latin square design. Rhodes grass hay was given ad libitum either alone, or with urea 7 g/day (U), or with leucaena 150 g/day (L150), or leucaena with urea (L150U), or leucaena 300 g/day (L300), or leucaena with urea (L300U). Digestible organic matter intake was increased significantly by leucaena supplementation although digestibility of the whole diet did not alter. Rumen fluid ammonia-N was not altered by leucaena supplementation, but was increased by urea. This suggests that Tarramba foliage protein has some resistance to ruminal degradation. Liquid and solids passage rates were not affected by the treatments. Microbial nitrogen supply to the intestine (g/day), and the efficiency of microbial nitrogen synthesis (g/kg organic matter apparently digested in the rumen), were increased by leucaena supplementation (P<0.01). Microbial protein synthesis was the only response in which 300 g/day air-dry Tarramba foliage gave improved results over 150 g/day.
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Horne, PM, i GJ Blair. "Forage tree legumes. IV. Productivity of leucaena/grass mixtures". Australian Journal of Agricultural Research 42, nr 7 (1991): 1231. http://dx.doi.org/10.1071/ar9911231.
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A field experiment was conducted in a wet tropical environment (Ciawi, West Java, Indonesia) to assess the forage yields of mixtures of leucaena and grasses over a 1 year period in plots which had been established 2 years earlier. The tree legume Leucaena leucocephala cv. Cunningham (plant density 1 m x 0.5 m), cut at either 30 cm or 100 cm, was interplanted with either a short grass (Setaria sphacelata var. splendida) or a tall grass (Pennisetum purpureum). Mineral nutrients were non-limiting. Highest leaf production was in the setaria monoculture (20.8 t ha-l yr-l) and the low-cut leucaena/setaria mixture (18.5 t ha-l yr-1), with the grass dominating production (> 88%) in the latter because of the ability of setaria to gain preferential access to light penetrating between the rows of leucaena early in each growth period. Leucaena shoot production in the low-cut leucaena treatments was reduced from a mean of 8.8 t ha-1 yr-1 in the monocultures to 1.5 t ha-l yr-1 in the mixtures. For the high-cut leucaena treatments, grass leaf yields were lower from the mixtures than from the monocultures but leucaena shoot yields were only reduced from monoculture yields in the mixture with pennisetum. The mixture of setaria and high-cut leucaena produced a considerable yield of setaria leaf (6.2 t ha-1 yr-l) with no reduction in leucaena leaf yields and intercepted a significantly greater percentage of total incident light (64%) than the other three mixtures (42-42%).
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Costa, Clésio dos Santos, Rosane Cláudia Rodrigues, Ricardo Alves de Araújo, Francisco Naysson de Sousa Santos, Giovanne Oliveira Costa Sousa, Juliana Rodrigues Lacerda Lima, Marcônio Martins Rodrigues, Ivone Rodrigues da Silva, Ana Paula Ribeiro de Jesus i Bruno Eduardo Caxias Miranda. "Nutritional composition of 'Ponta Negra' forage sorghum silage enriched with dried Leucaena leucocephala forage". Semina: Ciências Agrárias 40, nr 5Supl1 (7.08.2019): 2397. http://dx.doi.org/10.5433/1679-0359.2019v40n5supl1p2397.
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he aim of this study was to evaluate fermentation and chemical characteristics and the in situ degradability of sorghum silages enriched with dried Leucaena. The experiment was conducted as completely randomized design with four treatments (0 - control silage, silage without leucaena; 10.0, 20.0, or 30.0% inclusion of Leucaena) and five replicates, totaling 20 experimental units. The inclusion levels of leucaena influenced (P 0.05), with all silages having values above 90%. Gas loss decreased (P < 0.05) as the level of leucine increased in sorghum silage. A linear increase was observed for dry matter (P ? 0.0001) and crude protein (P = 0.0008) contents in response to Leucaena inclusion. There was a linear (P < 0.05) linear effect on neutral detergent fiber, hemicellulose and acid detergent fiber. As leucaena inclusion levels increased, for each 1% inclusion a reduction of 0.179 was observed; 0.059 and 0.119% for the values of neutral detergent fiber, hemicellulose and acid detergent fiber respectively. The inclusion of leucaena influenced (P < 0.05) the increase of silage lignin levels, probably due to the higher lignin content of the legume. The soluble fraction (a) of the silages increased along with the Leucaena inclusion levels, with highest values observed at the inclusion of 20 and 30% of the legume, respectively. Potential degradation (A) increased linearly with the levels of Leucaena added to the silage; the highest value for this variable was observed at 30% inclusion. Effective degradability (ED) increased up to the inclusion level of 20% (46.77%). Degradation rate (c) decreased markedly with the use of 30% Leucaena. The use of the forage part of Leucaena dried for three hours leads to reduced gas production, increased dry matter and crude protein contents, and decreased fiber contents. The degradability of dry matter increases up to the inclusion level of 20%.
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Radrizzani, Alejandro, H. Max Shelton i Scott A. Dalzell. "Response of Leucaena leucocephala pastures to phosphorus and sulfur application in Queensland". Animal Production Science 50, nr 10 (2010): 961. http://dx.doi.org/10.1071/an10062.
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A series of fertiliser trials were conducted on leucaena (Leucaena leucocephala subsp. glabrata) pastures growing on a range of soil types in south-east and central Queensland. The primary objective was to determine the extent of phosphorus (P) and sulfur (S) deficiencies in leucaena-grass pastures established on either virgin soils or previously cropped soils. Two experiments were conducted across nine sites and confirmed that, for many soils in Queensland, leucaena growth was restricted by P and S nutrient deficiencies, which limited plant growth directly and suppressed symbiotic N2 fixation. The major factors contributing to the P and S deficiencies and thus affecting leucaena response were: (i) inherent low soil fertility, (ii) nutrient removal by cropping and grazing, (iii) shallow soils, (iv) soil acidity, and (v) grass competition for available water and nutrients. A secondary treatment, inter-row cultivation, had little effect on leucaena growth but significantly increased grass growth in some soils. In all these experiments, leaf S concentrations and N : S ratios in index tissue were inconsistent indicators of adequacy of S. Similarly, leaf P concentrations were not useful indicators of P deficiency due to inappropriate (drought) leaf sampling conditions experienced in these experiments. The experiments demonstrate that the productivity of leucaena-grass pastures, especially in older leucaena plantations, will be limited by nutrient deficiencies on many soils in Queensland. While leucaena yield was suppressed, no foliar symptoms of nutrient deficiency were observed. Growers need to monitor the nutrient status of their leucaena-grass pastures by leaf tissue analysis using a new sampling protocol. Strategic fertiliser application has the potential to increase rainfall use efficiency by 50% with an expected parallel increase in cattle liveweight gain.
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Radrizzani, Alejandro, H. Max Shelton, Olena Kravchuk i Scott A. Dalzell. "Survey of long-term productivity and nutritional status of Leucaena leucocephala-grass pastures in subtropical Queensland". Animal Production Science 56, nr 12 (2016): 2064. http://dx.doi.org/10.1071/an15084.
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A survey of the productivity and nutritional status of leucaena (Leucaena leucocephala subsp. glabrata) pastures of different ages was conducted in subtropical Queensland from 2006 to 2008. Four leucaena stands (aged 8, 20, 31 and 38 years) growing on the same Vertosol soil type at Brian Pastures Research Station were surveyed. In the higher rainfall season of 2007–2008, leucaena yields and rainfall-use efficiency were highest in 8-year-old stands [2128 kg total dry matter (DM)/ha or 4.0 kg DM/ha.mm] and lowest in 38-year-old stands (978 kg total DM/ha or 1.9 kg DM/ha.mm). The reduced productivity in the 38-year-old leucaena pasture was associated with a decline in stem number/plant and leucaena plant density due to observed plant mortality. The reduced yield and vigour of aging leucaena was associated with nitrogen deficiency related to declining phosphorus and sulfur availability for adequate symbiotic N2 fixation and leucaena plant growth. Nutrient deficiencies of phosphorus and sulfur in leaf tissue were related to low to medium initial soil fertility (7–27 mg/kg of bicarbonate extractable phosphorus in the top 20 cm), coupled with inherent subsoil constraints (shallow soils, sodicity and high pH), and exacerbated by both long-term removal of nutrients by grazing animals and a reduction in soil phosphorus and sulfur availability over time. To maintain the productivity of leucaena pastures, plant nutritional status needs to be monitored in order to determine strategic fertiliser application.
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Valente, Tiago Neves Pereira, Erico Da Silva Lima, Bruno Borges Deminicis, Andréia Santos Cezário, Wallacy Barbacena Rosa dos Santos, Luana Almeida Souza i Vitória Gallo Borges de Lima. "Different Treatments for Breaking Dormancy of Leucaena Seeds (Leucaena leucocephala)". Journal of Agricultural Science 9, nr 3 (13.02.2017): 172. http://dx.doi.org/10.5539/jas.v9n3p172.
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The objective of the study was to evaluate the influence of methods for breaking dormancy the seeds of tropical forage legume Leucaena leucocephala (Lam.). The seed treatments were: (T1) water at 100 ºC/10 min; (T2) water at 100 ºC/1 min; (T3) Acetone (10 min); (T4) Ethyl alcohol (10 minutes); and (T5) intact seeds (control). Data were analyzed using a completely randomized design with eight replications, and it was adopted the Tukey test at 5% significance level. The treatment T1, had the highest speed of germination of seeds GSI, differed (P < 0.05). The T5 treatment (control) was the slowest response, that treatments that passed through some break dormancy until the seventh day after the beginning of the test (Germ7), with an amount of 20% accumulation of germinated seeds. The worst result of germination it was T5, with 30% of non-germinated seeds after 15 days of sowing.
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Nakamanee, G., S. Harrison, K. Janthibordee, W. Srisomporn i C. Phaikaew. "Potential of Leucaena spp. as a feed resource for ruminant animals in Thailand". Tropical Grasslands-Forrajes Tropicales 7, nr 4 (3.09.2019): 449–54. http://dx.doi.org/10.17138/tgft(7)449-454.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.While Leucaena leucocephala grows wild in Thailand, some Leucaena spp. have been introduced and evaluated for their edible forage yield and quality. Experiments on appropriate management were performed in different environments and productivity was found to be affected by species or cultivar. Environmental conditions, plant spacing, age of plant and cutting height significantly affected growth and performance. Edible forage yield was in the range of 5‒6 t DM/ha/yr. Most species and cultivars contain high protein concentrations and are suitable for use as feed supplements as well as total ration for livestock. The effects of leucaena feeding on livestock are shown in lower mortality and increased productivity. While the leaf meal processing of leucaena for livestock feeding is increasingly recognized and practiced, cultivation of this crop is still minimal and insignificant. The role and importance of leucaena for livestock production, as well as its nutritional quality and factors which limit its use, are reviewed. The need for increased cultivation and integration of leucaena into local farming systems is emphasized. There is an urgent need to increase research support for the efficient cultivation of leucaena and an education campaign to dispel concerns about toxicity aspects.
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George, M. L. C., J. P. W. Young i D. Borthakur. "Genetic characterization of Rhizobium sp. strain TAL1145 that nodulates tree legumes". Canadian Journal of Microbiology 40, nr 3 (1.03.1994): 208–15. http://dx.doi.org/10.1139/m94-034.
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Rhizobium sp. strain TALI 145 nodulates Leucaena ieucocephaia and Phaseolus vulgaris, in addition to a wide range of tropical tree legumes. Six overlapping clones that complemented nodulation defects in leucaena and bean rhizobia were isolated and a 40-kb map of the symbiosis region was constructed. The common nod and nifA genes were situated approximately 17 kb apart, with the nodlJ genes in between. These clones enabled a derivative of TAL1145 carrying a partially deleted pSym to form ineffective nodules on both leucaena and bean, and a similar derivative of Rhizobium etli TAL182 to form ineffective nodules on bean. When two representative clones, pUHR9 and pUHR114, were each transferred to wild-type rhizobial strains, they allowed ineffective nodulation by Rhizobium meliloti on both leucaena and bean and by Rhizobium leguminosarum bv. viciae on bean. Transconjugants of R. leguminosarum bv. trifolii formed effective nodules on leucaena and ineffective nodules on bean. Tn5 mutagenesis of the symbiosis region resulted in a variety of nodulation and fixation phenotypes on leucaena and bean. On the basis of 16S rRNA sequences, TAL1145 was found to be distinct from both R. tropici and NGR234, the two groups of leucaena symbionts that were previously described.Key words: Rhizobium, Leucaena leucocephala, nodulation, nitrogen fixation.
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Buck, Stuart, Joe Rolfe, Craig Lemin i Bernie English. "Adoption, profitability and future of leucaena feeding systems in Australia". Tropical Grasslands-Forrajes Tropicales 7, nr 4 (3.09.2019): 303–14. http://dx.doi.org/10.17138/tgft(7)303-314.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.Leucaena (Leucaena leucocephala ssp. glabrata) is a highly palatable and productive forage used mainly by beef producers on extensive properties in northern Australia. When sown into native or sown grass pastures, leucaena provides significant production, economic, environmental and social benefits. Adoption of leucaena was slow initially due to a range of technical, agronomic and landscape factors. These have now been largely overcome through extensive research, development, producer experience and other advances, resulting in around 130,000 ha of cultivated leucaena being utilized across northern Australia.A range of aspects will need to be addressed if the adoption of leucaena is to be accelerated into the future. These include environmental concerns, especially potential weediness, and a range of technological needs, including soil nutritional requirements, grazing and toxicity management, opportunities for companion fodder systems and conservation options. Advances in technology and the ongoing need for a high-quality, profitable and sustainable perennial forage will ensure the continued adoption of leucaena across northern Australia for the foreseeable future.
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Kenny, Sean, i Geoff Drysdale. "Current and future adoption of leucaena-grass pastures in northern Australia". Tropical Grasslands-Forrajes Tropicales 7, nr 4 (3.09.2019): 315–30. http://dx.doi.org/10.17138/tgft(7)315-330.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.The leucaena-grass pastures and target markets for adoption project was commissioned by Meat & Livestock Australia (MLA) to examine the scope for further adoption of leucaena-grass pastures in northern Australia. Drawing upon stakeholder and producer interviews, focus groups, mapping of biophysical factors critical to growing leucaena and a review of existing literature, regional adoption profiles were developed using the ADOPT model. This work outlines the current and future potential for adoption of leucaena in northern Australia and recommends 5 interrelated strategic actions designed to support the ongoing adoption. These actions have been designed to address the complex technical, social and biophysical requirements for successful adoption and will require collaboration between investors, The Leucaena Network, producers, government agencies and the private sector to be effective.
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Dalzell, Scott A. "Leucaena cultivars – current releases and future opportunities". Tropical Grasslands-Forrajes Tropicales 7, nr 2 (31.05.2019): 56–64. http://dx.doi.org/10.17138/tgft(7)56-64.
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Plenary paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.The Leucaena genus is made up of 24 different species (19 diploid and 5 tetraploid species). However, early use of the Leucaena genus in commercial agricultural systems was based entirely upon a very narrow germplasm base. A single genotype of Leucaena leucocephala ssp. leucocephala (‘common’ leucaena) was spread pantropically from its center of origin in Mexico over 400 years ago. Genetic improvement of Leucaena leucocephala began in the 1950s, when vigorous ‘giant’ leucaena (L. leucocephala ssp. glabrata) was identified in Australia and Hawaii. Cultivars such as Hawaiian Giant K8, Peru and El Salvador were selected and promoted for grazing in Australia and multipurpose agroforestry uses throughout the tropics. Plant breeding for improved forage production resulted in the release of cv. Cunningham in 1976 in Australia. These cultivars of ‘giant’ Leucaena leucocephala displayed broad environmental adaptability, with the exception of poor tolerance of cold temperatures (and frost) and acid soils. The outbreak of the psyllid insect pest (Heteropsylla cubana) from Cuba during the 1980s devastated both ‘common’ and ‘giant’ leucaena all around the world. This challenge resulted in renewed interest in lesser-known Leucaena spp. that exhibited tolerance to the pest and in interspecific hybridization as a means of developing new cultivars. Some ‘giant’ leucaena lines exhibited excellent agronomic traits and a degree of tolerance to the psyllid pest and this resulted in the release of new cultivars in Australia (cvv. Tarramba and Wondergraze) and Hawaii (cv. LxL). Since the 1990s, plant breeding programs have sought to develop cultivars with greater psyllid tolerance using interspecific hybridization. This has resulted in the release of cv. ‘KX2-Hawaii’ for timber and forage production, and a backcrossed forage cultivar cv. Redlands (Australia). Both cultivars are based upon interspecific hybridization between L. pallida and L. leucocephala ssp. glabrata. Cold-temperature and acid-soil tolerance have been pursued in South American breeding programs based upon L. diversifolia, without commercial success. The development of sterile Leucaena spp. cultivars is currently underway to nullify the environmental weed potential of all current commercial cultivars. Tolerance to cold temperatures (L. diversifolia, L. pallida, L. pulverulenta and L. trichandra), frost (L. greggii and L. retusa) and psyllids (L. collinsii) exists within the Leucaena genus and may be exploited in future hybridization programs. New genetic analyses and molecular plant breeding techniques have the potential to facilitate further gene transfer between Leucaena spp. for the development of the next generation of multipurpose cultivars.
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Goodchild, A. V., i N. P. McMeniman. "Intake and digestibility of low quality roughages when supplemented with leguminous browse". Journal of Agricultural Science 122, nr 1 (luty 1994): 151–60. http://dx.doi.org/10.1017/s0021859600065904.
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SUMMARYIn the first two of four experiments, sheep were fed,ad libitum, sorghum stover supplemented with graded levels of foliage of the shrub leucaena (Leucaena leucocephald) or mulga (Acacia aneura), which provided between 0 and 0·34 or between 0 and 0·43 of the dietary dry matter (DM) respectively. A second treatment (with or without urea) was superimposed in a factorial design. The effect of treatments on liveweight (LW) was explainable by their effects on voluntary intake of apparently digestible organic matter (DOMI). D0M1 was increased by mulga, largely due to an increase in the total voluntary intake of organic matter (OM). Leucaena increased DOMI by increasing the ration OM digestibility and, at low levels of inclusion, intake of the basal diet. Roughage intake was greatest when leucaena provided 0·15–0·20 of the dietary DM. Leucaena increased rumen ammonia, and whenever roughage intake was increased by urea, leucaena also increased it.In the third experiment, when diets were made isonitrogenous with urea, roughage intake was slightly greater when leucaena, rather than its ash or a mineral mixture, was supplemented. Total OM intake and DOMI were greatest when leucaena was fed.In the final experiment, sheep were fed one of ten treatments: three basal diets (two of sorghum stover and the third of native pasture hay) each supplemented with legumes (leucaena to the hay and one stover diet and cowpea straw to the second stover diet), ash of the respective legume and formaldehyde-treated casein. The tenth treatment was sorghum stover plus urea. For sorghum stover diets with leucaena-based or cowpea straw-based supplements, DOMI responded linearly to the nonurea nitrogen concentration of the diet. On the other hand, for native hay with leucaena-based supplements, the response of DOMI to non-urea N was negligible. It was noted that the native hay (predominantly Flinders grass,Iseilema vaginiflorum), contained lower concentrations of polyphenols than sorghum stover.It was concluded that browse foliage can increase the voluntary DOMI of sheep consuming low quality roughages by providing nitrogen and sometimes minerals and OM of greater digestibility. The slowly-degradable proteins in leucaena, cowpea straw or formaldehyde-treated casein are more effective with polyphenol-rich sorghum stover than with native hay of otherwise similar composition.
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Halliday, Michael J., Hayley E. Giles, Jagadish Padmanabha, Chris S. McSweeney, Scott A. Dalzell i H. Max Shelton. "The efficacy of a cultured Synergistes jonesii inoculum to control hydroxypyridone toxicity in Bos indicus steers fed leucaena/grass diets". Animal Production Science 59, nr 4 (2019): 696. http://dx.doi.org/10.1071/an17853.
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An experiment was conducted to investigate the efficacy of a cultured Synergistes jonesii inoculum in degrading the Leucaena leucocephala (leucaena) toxins: 3-hydroxy-4(1H)-pyridone and 3-hydroxy-2(1H)-pyridone (3,4- and 2,3-DHP). Sixteen stall-housed Bos indicus steers naïve to leucaena were fed varying combinations of forage-harvested leucaena and Chloris gayana (Rhodes grass). Dietary treatments, offered at 25 g dry matter/kg LW.day, were: 25% leucaena; 50% leucaena; 100% leucaena; and 50% leucaena, switched to 50% Medicago sativa (lucerne) after 6 weeks at time of inoculation. The experiment was 10 weeks in duration, consisting of a 6-week pre-inoculation period, followed by inoculation with cultured S. jonesii, and a 4-week post-inoculation period. Mean daily dry matter intake was recorded. Twenty-four-hour urine collections and rumen fluid samples were obtained weekly for estimation of total urinary DHP, and detection of S. jonesii using nested polymerase chain reaction analysis including presence of single nucleotide polymorphisms (SNP), respectively. In the pre-inoculation period, total urinary DHP increased quickly to high levels, then gradually declined after Week 3 with 2,3-DHP the dominant isomer through to Week 6. Indigenous strains of S. jonesii were sporadically detected by PCR analysis, indicating S. jonesii was present before inoculation but at the lower limits of detection. After inoculation there was no change in the rate of total DHP degradation or the frequency of detection of S. jonesii, although there was increased rate of degradation of 2,3-DHP. SNP indicated the presence of different strains of S. jonesii in both indigenous and cultured S. jonesii. DMI was low, especially in the 100% treatment, due in part to the high stem content of the forage-harvested leucaena and probable DHP toxicosis. It was concluded that the cultured S. jonesii inoculum did not fully protect animals against leucaena toxicity.
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Radrizzani, Alejandro, H. Max Shelton, Scott A. Dalzell i Gunnar Kirchhof. "Soil organic carbon and total nitrogen under Leucaena leucocephala pastures in Queensland". Crop and Pasture Science 62, nr 4 (2011): 337. http://dx.doi.org/10.1071/cp10115.
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Soil organic carbon (OC) and total nitrogen (TN) accumulation in the top 0–0.15 m of leucaena–grass pastures were compared with native pastures and with continuously cropped land. OC and TN levels were highest under long-term leucaena–grass pasture (P < 0.05). For leucaena–grass pastures that had been established for 20, 31, and 38 years, OC accumulated at rates that exceeded those of the adjacent native grass pasture by 267, 140, and 79 kg/ha.year, respectively, while TN accumulated at rates that exceeded those of the native grass pastures by 16.7, 10.8, and 14.0 kg/ha.year, respectively. At a site where 14-year-old leucaena–grass pasture was adjacent to continuously cropped land, there were benefits in OC accumulation of 762 kg/ha.year and in TN accumulation of 61.9 kg/ha.year associated with the establishment of leucaena–grass pastures. Similar C : N ratios (range 12.7–14.5) of soil OC in leucaena and grass-only pastures indicated that plant-available N limited soil OC accumulation in pure grass swards. Higher OC accumulation occurred near leucaena hedgerows than in the middle of the inter-row in most leucaena–grass pastures. Rates of C sequestration were compared with simple models of greenhouse gas (GHG) emissions from the grazed pastures. The amount of carbon dioxide equivalent (CO2-e) accumulated in additional topsoil OC of leucaena–grass pastures ≤20 years old offset estimates of the amount of CO2-e emitted in methane and nitrous oxide from beef cattle grazing these pastures, thus giving positive GHG balances. Less productive, aging leucaena pastures >20 years old had negative GHG balances; lower additional topsoil OC accumulation rates compared with native grass pastures failed to offset animal emissions.
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Radrizzani, Alejandro, Nahuel A. Pachas, Luis Gándara, Cristina Goldfarb, Alejandro Perticari, Santiago Lacorte i Dante Pueyo. "Leucaena feeding systems in Argentina. I. Five decades of research and limitations for adoption". Tropical Grasslands-Forrajes Tropicales 7, nr 4 (3.09.2019): 381–88. http://dx.doi.org/10.17138/tgft(7)381-388.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.This review describes the history of research in Leucaena leucocephala (leucaena) feeding systems carried out by the National Institute of Agricultural Technology (INTA) over the last 5 decades and discusses the main limitations resulting in poor adoption in Argentina. Leucaena was introduced in the subtropical region of the north of the country in the late 1960s and early 1970s. Since then, INTA has conducted research to evaluate forage and animal productivity, leucaena accessions, rhizobial strains, contribution to soil carbon and total nitrogen and density effects on competition and other ecosystem interactions in silvopastoral systems. In spite of the convincing research results showing the excellent potential of leucaena to increase forage quality and animal production in suitable areas, there has been poor adoption of this forage tree legume on a broad scale.
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Revell, Clinton, Geoff Moore, Daniel Real i Sam Crouch. "Environmental adaptation of leucaena in Western Australia – challenges and opportunities". Tropical Grasslands-Forrajes Tropicales 7, nr 2 (31.05.2019): 112–19. http://dx.doi.org/10.17138/tgft(7)112-119.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.There is considerable interest from Western Australian (WA) pastoralists on the potential role of leucaena (Leucaena leucocephala) in northern WA, where the potential area for dryland production of species of the genus Leucaena is high. Although it is highly regarded for animal production in other countries and in Queensland, leucaena is a contentious species since its status as an environmental weed precludes it from use on pastoral leases in the Kimberley and Pilbara regions of WA. Development of sterile/seedless forms would overcome risks of spread of the species as a weed. The key environmental constraints to growth of leucaena are likely to be the length of the dry season and low fertility of most soils other than the grey/black cracking clays (vertosols). Psyllid resistance and cool temperature tolerance are likely to be of secondary importance. Opportunities for irrigated production are also emerging and may allow leucaena species to be used in environments previously considered well outside their home-range. It is desirable now to re-examine the diversity of the wider leucaena genus for adaptation to WA conditions generally and for the purpose of selecting elite parent material for use in a sterile/seedless leucaena breeding program. These perennial species that can be under production for 30 to 40 years need to be evaluated in the target environments for at least 3‒5 years to fully understand their potential as adult plants.
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Banegas, Natalia, Roberto Corbella, Emilce Viruel, Adriana Plasencia, Belen Roig i Alejandro Radrizzani. "Leucaena leucocephala introduction into a tropical pasture in the Chaco region of Argentina. Effects on soil carbon and total nitrogen". Tropical Grasslands-Forrajes Tropicales 7, nr 4 (3.09.2019): 295–302. http://dx.doi.org/10.17138/tgft(7)295-302.
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Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.The introduction of leucaena (Leucaena leucocephala), apart from increasing animal production, improves soil fertility through biological nitrogen (N) fixation and its deep-rooted system. There is limited information on carbon and N dynamics in hedgerow silvopastoral systems, particularly in the subsoil profile. The concentrations and vertical distribution of organic carbon (OC) and total N , and their fractions (particulate and associate forms) in the profile (0‒100 cm) of a 4-year-old leucaena stand in a Urochloa brizantha-Chloris gayana pasture were compared with those in the adjacent pure tropical grass (U. brizantha) pasture. Leucaena introduction increased the OC concentration in the subsoil (20‒100 cm) by 45%, particularly the stable form (associate OC) in the deepest horizon (50‒100 cm). This was attributed to a greater abundance of leucaena roots deeper in the profile than for grass. Leucaena also enhanced by 7.6% the N concentration (from 0.131 to 0.141%) in the topsoil (0‒20 cm) associated with an increment in the labile form (particulate organic N), due to leaf deposition, recycling of animal feces and nodule-N turnover from N fixation. Leucaena establishment has the potential to improve soil fertility and hence availability of N to companion grass growth, and can be utilized as a greenhouse gas mitigation strategy.
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Hidayat, Taupik, Baharuddin Hamzah i Minarni R. Jura. "Determination of Total Flavonoid Contents and Antioxidant Activity of Leucaena Leucocephala Leaves's Extract". Jurnal Akademika Kimia 9, nr 2 (29.05.2020): 70–77. http://dx.doi.org/10.22487/j24775185.2020.v9.i2.pp70-77.
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The study of the determination of total flavonoid contents and antioxidant activity of extract of Leucaena leucocephala leaves had been carried out using UV-Vis spectrophotometry method. This study aimed to determine the total flavonoid contents and the antioxidant power of Leucaena leucocephala extract. Extraction of chemical content from Leucaena leucocephala was carried out by the maceration method using absolute ethanol. The total flavonoid contents from the sample extract were taken up for absorption at wavelength 510 nm and 700 nm. The variation of the concentration of Leucaena leucocephala leaves' extract was respectively 20, 40, 60, and 80 ppm. The results of the study showed that the total flavonoid contents of extracts of Leucaena leucocephala leaves was 2.242 g/100 grams. The antioxidant activity of Leucaena leucocephala leaves extract was carried out using DPPH (1,1-diphenyl-2-picrylhydrazine) and the measurement of absorption was at a wavelength of 517 nm, and by varying the sample concentration. Positive control used was vitamin C solution with the same variation of extract's concentration. The results showed that the IC50 values of Leucaena leucocephala leaves extract and vitamin C were 175.388 and 28.907 ppm. Based on the IC50 data it can be stated that the antioxidant vitamin C was stronger than the Leucaena leucocephala leaves extract which was classified as a weak type of natural antioxidant.
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Conrad, K. A., R. C. Dalal, D. E. Allen, R. Fujinuma i Neal W. Menzies. "Free light fraction carbon and nitrogen, a physically uncomplexed soil organic matter distribution within subtropical grass and leucaena–grass pastures". Soil Research 56, nr 8 (2018): 820. http://dx.doi.org/10.1071/sr18162.
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Quantifying the size and turnover of physically uncomplexed soil organic matter (SOM) is crucial for the understanding of nutrient cycling and storage of soil organic carbon (SOC). However, the C and nitrogen (N) dynamics of SOM fractions in leucaena (Leucaena leucocephala)–grass pastures remains unclear. We assessed the potential of leucaena to sequester labile, free light fraction (fLF) C and N in soil by estimating the origin, quantity and vertical distribution of physically unprotected SOM. The soil from a chronosequence of seasonally grazed leucaena stands (0–40 years) was sampled to a depth of 0.2m and soil and fLF were analysed for organic C, N and δ13C and δ15N. On average, the fLF formed 20% of SOC and 14% of total N stocks in the upper 0.1m of soil from leucaena rows and showed a peak of fLF-C and fLF-N stocks in the 22-year-stand. The fLF δ13C and fLF δ15N values indicated that leucaena produced 37% of fLF-C and 28% of fLF-N in the upper 0.1m of soil from leucaena rows. Irrespective of pasture type or soil depth, the majority of fLF-C originated from the accompanying C4 pasture-grass species. This study suggests that fLF-C and fLF-N, the labile SOM, can form a significant portion of total SOM, especially in leucaena–grass pastures.