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1
Khan, Nazish Huma, Mohammad Nafees, Tooba Saeed, Abdullah Khan, and Adila Bashir. "Accumulation and Translocation of Micro-Nutrients in Soil and Plants of Orchard and Non-Orchard Fields." Biological Sciences - PJSIR 63, no. 3 (November 13, 2020): 187–98. http://dx.doi.org/10.52763/pjsir.biol.sci.63.3.2020.187.198.
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The present study was conducted in the Plum orchard zone of district Peshawar. The study was aimed to investigate the levels of different micronutrients in the orchard soil and crop in corresponding to non-orchards. For this purpose, samples of soil and seasonal crop (wheat crop) were collected from both orchard and non-orchard fields. The collected samples were analyzed for various metals such as Mn, Fe, Cu, Zn, Cd, Cr, Ni and Co through Atomic Absorption Spectrophotometer. The results showed that in orchard soils, mean concentrations of Mn (486.9 mg/Kg), Cu (81.66 mg/Kg), Cd (2.21 mg/Kg), Cr (54.2 mg/Kg) and Ni (27.9 mg/Kg) were observed above their allowable limits. Similarly, in orchard wheat crops, a higher accumulation of Fe (416.1 mg/Kg), Cu (18.6 mg/Kg), Cr (1.5 mg/Kg) and Cd (0.63 mg/Kg) was calculated in the wheat grain/seed part. In non-orchards, all metals were found at safe levels. Analysis of the irrigation water revealed higher limits of Mn (0.06 mg/L), Fe (1.94 mg/L), Cd (1.29 mg/L), Cr (3.14 mg/L) and Ni (1.23 mg/L). Geo-accumulation Index showed a moderate and heavy level of contamination in orchard soils (Igeo. <1, 2). Higher uptakes of Mn (0.81) and Cu (0.87) were calculated in wheat crops of orchards through Transfer Factor (TF). Based on the observations, it is concluded that metals enrichment in orchard fields can be attributed due to excessive applications of fungicide sprays, fertilizers and contaminated water sources that introduce trace-elements into the soil and are subsequently absorbed by plants. Therefore, it is considered important to take appropriate measures to monitor the soils, crops and water for different micronutrients.
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Burcaw, Jeffrey W., Bruce W. Wood, and Michael W. Pool. "620 PB 328 MATHEMATICAL MODELLING OF INTERTREE SHADING IN HEDGEROW AND NON-INTERSECTING CANOPY ORCHARD SYSTEMS AND ITS IMPLICATIONS ON OPTIMAL ORCHARD DESIGN." HortScience 29, no. 5 (May 1994): 521b—521. http://dx.doi.org/10.21273/hortsci.29.5.521b.
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The authors have developed a mathematical model designed for shade-intolerant tree crops which describes the amount of intertree shading in an orchard. These data are used to formulate an optimal orchard design based on shading reduction in orchards for any tree crop during any developmental window at any global location for either continuous canopy hedgerows or non-intersecting canopies for several different orchard geometries. Variables include tree shape, orchard geometry intertree spacing, row orientation, time and day of year, and geographical coordinates. Optimal orchard designs are based upon the total amount of unshaded canopy surface per unit area which each orchard configuration confers. Results indicate extensive variability of intertree shading between hedgerow and non-intersecting canopies to be largely a function of latitude, regardless of other variables.
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El-Kassaby, Y. A., M. U. Stoehr, D. Reid, C. G. Walsh, and T. E. Lee. "Clonal-row versus random seed orchard designs: interior spruce mating system evaluation." Canadian Journal of Forest Research 37, no. 3 (March 2007): 690–96. http://dx.doi.org/10.1139/x06-248.
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Mating system pattern (selfing or outcrossing and correlated matings levels) comparisons between two interior spruce seed orchard designs (clonal-row and random) managed under intensive crown and pollen management were conducted. Crown manipulation consisted of tree topping and branch pruning, while pollen management involved multiple supplemental mass-pollination applications during peak seed-cone reproductive receptivity and pollen agitation using helicopters. Significant differences between orchards’ multilocus outcrossing rate estimates were observed, and both estimates significantly departed from complete outcrossing (t = 1.0). Clonal arrangements in the clonal-row design permitted higher chances for selfing (t = 0.948) in comparison with those of the random design (t = 0.989). Intensive pollen management, while effective, still produced a minor component of selfing. Both orchard designs produced similar individual tree's outcrossing rate trends with the majority showing high outcrossing, while few individuals showed high selfing propensity. Estimates of correlated mating varied substantially between the two seed orchard designs with 9.3% and 4.3% for the clonal-row and random seed orchards, respectively. While small but significant differences in the genetic quality of the seed crops were observed between the two orchard designs, the establishment of clonal-row seed orchards should be given serious considerations specifically under committed pollen and crown management. The ease of crop and orchard management in the clonal-row design outweighs the observed differences in the seed crop genetic quality. A slight modification to the clonal-row design is proposed and is expected to reduce the observed minor genetic quality differences between the two orchard designs.
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Burcaw, Jeffrey W., Bruce W. Wood, Michael W. Poole, and Mark T. Burnette. "MATHEMATICAL MODELLING OF TREE CROP ORCHARD DESIGN: INTERTREE SHADING DURING CRITICAL SEASONAL GROWTH AND DEVELOPMENTAL WINDOWS AND ITS IMPLICATIONS ON OPTIMAL SPACING." HortScience 28, no. 5 (May 1993): 556c—556. http://dx.doi.org/10.21273/hortsci.28.5.556c.
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The authors have developed a computer model designed for shade-intolerant tree crops which describes the amount of intertree shading in an orchard. These data are used to formulate an optimal orchard design based on shading reduction in orchards for any tree crop during any developmental window at any global location.Tree shape is modelled as an ellipsoid bisected about the semi-minor axis, with ellipsoid dimensions and eccentricity altered to reflect growth stages of the trees. Intertree shading is measured as the surface area of the projected shadow on the ellipsoid. Variables include crop, light extinction, ellipsoid dimensions, intertree spacing, orchard geometry, time and day of the year, and geographical coordinates. Simulations compared the sunlight-related attributes of a variety of orchard geometries for different growth phases of the trees during different parts of the year for several global locations. Results indicate extensive variability of intertree shading to be a function of latitude, regardless of other variables.
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O'Connell, M. G., I. Goodwin, and G. M. Dunn. "Towards a better understanding of crop water requirement in orchards: a case study from the Goulburn Valley." Australian Journal of Experimental Agriculture 46, no. 3 (2006): 405. http://dx.doi.org/10.1071/ea04009.
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Responses of fruit trees to reduced irrigation in micro-irrigated peach and apple orchards in the Goulburn Valley, Victoria were investigated during the 2000–01 season. Field experiments examined the effects of applying 2 irrigation levels on soil water content, crop water relations, vegetative growth, yield, yield components and fruit quality. Irrigation regimes were 50% and 100% of current management practice where inputs are scheduled from pan evaporation and locally derived crop coefficients. Water was applied to only one side of the tree rootzone in the 50% treatment (0.5I) while the current management practice treatment (1.0I), received water on both sides of the tree. Over the season, the irrigation inputs for peach and apple equated to a crop coefficient of 0.93 and 0.87, respectively. Orchard water use (ETpeach and ETapple) was predicted using reference crop evapotranspiration (ET0) and published crop coefficients (Kc) with adjustment for the fraction of shade cast by the trees on the orchard floor at solar noon (effective canopy cover, ECC). Throughout the season, ECC measured as midday tree canopy radiation interception, remained low for both peach and apple (<35%). ETpeach and ETapple were substantially lower than current water scheduling practices (1.0I treatments). For the 0.5I apple regime, irrigation closely matched ETapple suggesting that these trees were adequately irrigated. This was supported by no detrimental effects on crop production, vegetative growth, and fruit quality measures of the 0.5I irrigation regime. However, in the peach orchard the 0.5I regime reduced fruit volume suggesting that these trees may have been water stressed. Based on ECC, we calculated the full crop water requirement Kc for the peach and apple orchards to be 0.42 and 0.37, respectively. In summary, for the apple orchard, our 0.5I treatment was close to predicted full crop water requirement (ETapple). But for the peach orchard, the ETpeach was greater, albeit slightly, than our 0.5I regime. Taken overall, these results demonstrate that better matching of water application to the evaporative surface of the orchard canopies (i.e. ECC) can substantially reduce irrigation water use in Goulburn Valley orchards. It is also apparent that ECC in these orchards where row spacing is typically 4–5 m can be relatively low.
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Shuleva, Stanimira, Velichko Gagov, and Petar Zhelev. "Outcrossing rates in two seed orchards of Pinus nigra Arn. in Bulgaria." Silva Balcanica 24, no. 1 (February 28, 2023): 47–54. http://dx.doi.org/10.3897/silvabalcanica.24.e101560.
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Seed orchards are an important source of seeds with improved genetic quality. Here we present results of a study on the genetic composition of seed orchards crop of Austrian black pine (Pinus nigra Arn.). Two seed orchards were included in the study – a clonal seed orchard established near Sliven, and a seedling seed orchard, established in the region of Simitli. The outcrossing rates were higher in the clonal seed orchard (Sliven), 0.873 and 0.806 multi-locus (tm) and single-locus (ts) estimates, respectively. The same values were 0.623 and 0.530, respectively, in the seedling seed orchard (Simitli). The inbreeding coefficient was positive in both cases, but was significantly different from zero in the clonal seed orchard only (0.101 vs. 0.032). Thus, the two studied seed orchards demonstrate different genetic efficiency. The results are discussed in relation to seed orchard management and efficiency.
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Jia, Qiong, and Yan-Ping Wang. "Relationships between Leaf Area Index and Evapotranspiration and Crop Coefficient of Hilly Apple Orchard in the Loess Plateau." Water 13, no. 14 (July 16, 2021): 1957. http://dx.doi.org/10.3390/w13141957.
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Drought and water shortage are the key factors that restrict the sustainable development of the apple industry in the Chinese Loess Plateau. The accurate prediction of ET can provide a scientific basis for water management of apple orchards. A study on the relationship between LAI, ET and crop coefficient Kc under water deficit is particularly necessary for the accurate prediction of ET in apple orchards. In this work, the crop coefficient Kc under water deficit was defined as the product of the crop coefficient KcI under no water stress and the water stress coefficient Ks, namely Kc = KcI × Ks. LAI and ET of the hilly apple orchard were measured from April to September in 2019 and 2020. The results showed: (1) The LAI of the apple orchard showed a trend of rapid increase—moderate increase—declined during the growth period, with 0.26–2.16 [m2 m−2] variation range; (2) The ET of the orchard was greater than the rainfall, the maximum ET was in July or August. The maximum components of ET in the apple orchard was E, with 47.8–49.1% of ET; T accounted for 42.5–43.9% of ET; Ic accounted for only 9.1–9.6% of ET; (3) There was a significant exponential relationship between the LAI and T or ET. The crop coefficient KcI under no water stress changed with the development of the apple tree canopy. The variation of water stress Ks was basically consistent with the variation of rainfall; (4) There is a significant exponential relationship between LAI and crop coefficient Kc under water deficit (Kc = 0.1141e1.0665LAI, R2 = 0.7055, p < 0.01). This study demonstrates that LAI could be used to estimate the crop coefficient Kc of apple orchards under water deficit in the Loess Plateau, and the actual evapotranspiration of apple orchards in this region could be predicted.
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Grosser, C., B. M. Potts, and René E. Vaillancourt. "Microsatellite Based Paternity Analysis in a Clonal Eucalyptus nitens Seed Orchard." Silvae Genetica 59, no. 1-6 (December 1, 2010): 57–62. http://dx.doi.org/10.1515/sg-2010-0007.
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Abstract Microsatellite markers were used to determine paternity in 473 open-pollinated progenies from a clonal Eucalyptus nitens seed orchard of 50 trees from 12 different genotypes. The outcrossing rate in this orchard was high, averaging 0.85 (weighted by capsule crop) but variable between trees (ranging from 0.6-1.0). Paternal contribution of each genotype to the open-pollinated seed crop was predicted by the size of the flower crop of each genotype (r = 0.76), but not the number of ramets. While the detectable contamination in this orchard is relatively low (4.5%), it is atypical when compared to other published estimates in eucalypt seed orchards suggesting that with suitable buffering low levels of contamination can be achieved.
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Žalac, Helena, Vladimir Zebec, Vladimir Ivezić, and Goran Herman. "Land and Water Productivity in Intercropped Systems of Walnut—Buckwheat and Walnut–Barley: A Case Study." Sustainability 14, no. 10 (May 17, 2022): 6096. http://dx.doi.org/10.3390/su14106096.
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Intercropping arable crops in orchards is a sustainable land use for intensifying agricultural production, under the condition of plants’ complementarity in sharing resources. This study investigated the aspects of water use and yields in intercropped systems of walnut and crops. To assess possible temporal complementarity between crops and trees, a summer crop—buckwheat—and a winter crop—barley—were intercropped in walnut orchards. The land and water productivity were studied under two designs: in an older, denser orchard and a younger one, with wider tree spacing. The results showed a reduction in yields and water productivity (WP) of intercrops due to the competition with walnut trees, with the exception of buckwheat in the younger orchard, where this summer crop surprisingly achieved the highest yield and WP. Nevertheless, in the system with mature fruiting trees, intercropping with winter barley was 53% more productive per unit of land and 83% more water-productive than growing walnut and barley separately but also 48% more land-productive and 70% more water-productive than the walnut–buckwheat system. Our results indicate positive effects of trees on microclimates but also emphasize the importance of species selection and systems design on the overall productivity of intercropped systems.
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Peisley, Rebecca K., Manu E. Saunders, and Gary W. Luck. "Cost-benefit trade-offs of bird activity in apple orchards." PeerJ 4 (June 30, 2016): e2179. http://dx.doi.org/10.7717/peerj.2179.
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Birds active in apple orchards in south–eastern Australia can contribute positively (e.g., control crop pests) or negatively (e.g., crop damage) to crop yields. Our study is the first to identify net outcomes of these activities, using six apple orchards, varying in management intensity, in south–eastern Australia as a study system. We also conducted a predation experiment using real and artificial codling moth (Cydia pomonella) larvae (a major pest in apple crops). We found that: (1) excluding birds from branches of apple trees resulted in an average of 12.8% more apples damaged by insects; (2) bird damage to apples was low (1.9% of apples); and (3) when trading off the potential benefits (biological control) with costs (bird damage to apples), birds provided an overall net benefit to orchard growers. We found that predation of real codling moth larvae was higher than for plasticine larvae, suggesting that plasticine prey models are not useful for inferring actual predation levels. Our study shows how complex ecological interactions between birds and invertebrates affect crop yield in apples, and provides practical strategies for improving the sustainability of orchard systems.
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Štefanić, Edita, Vesna Kovačević, Lea Jakovljević, Urška Kosić, Dinko Zima, and Alka Turalija. "Weed Community in a Conventionally-Grown Olive Orchard Vs. Weed Community in Consociation with Pyrethrum (Tanacetum cinerariifolium (Trevir.) Sch. Bip.)." Poljoprivreda 27, no. 1 (June 1, 2021): 30–36. http://dx.doi.org/10.18047/poljo.27.1.4.
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On the experimental plots of the Institute of Agriculture and Tourism in Poreč, weed communities were analyzed in a conventionally‐grown olive orchard and in consociation with pyrethrum. Phytocenological surveys were conducted in March, June, and September using the Braun-Blanquet Cover Abundance Scale. Altogether, 54 species of vascular plants were recognized in both orchards. However, in a conventionally‐grown olive orchard, 27 were identified, whereas 42 weed species were identified in consociation with pyrethrum. Only 15 weeds were common to both orchards. Between both olive orchards, significant differences existed regarding the floristic and community diversity metrics. In consociation with pyrethrum as a cover crop, olive orchard had a more stable weed community during the season, while two weed species, Mercurialis annuua L. and Medicago arabica (L.) Huds., dominated in a conventionally‐grown orchard in the fall. The weed communities in both orchards significantly differ considering the appearance season (spring, summer, and fall). An autumnal weed community in a conventionally‐grown olive orchard was more diverse, more abundant, and with a more distinct floristic composition than a weed community in the spring and summer periods. However, an olive‐orchard weed community in consociation with pyrethrum also differed regarding the season, but a Canonical Correspondence Analysis (CCA) demonstrated a clear separation of a more diverse estival weed community than the one observed in the spring and summer.
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McBrydie, H. M., B. G. Howlett, and D. E. Pattemore. "Relative abundance and movement of flower visitors within ‘Black Doris’ plum orchards in Hawke’s Bay, New Zealand." New Zealand Plant Protection 70 (August 8, 2017): 58–62. http://dx.doi.org/10.30843/nzpp.2017.70.28.
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The Japanese plum ‘Black Doris’ (Prunus salicina) is a self-infertile early-flowering crop so insufficient cross pollination and lack of pollinators could be factors to explain reported poor fruit set. This project assessed the relative abundance of flower visitors within a plum orchard and their movements among three orchards, as part of a wider study on plum pollination. Insect surveys conducted over three days across one orchard in 2014 identified a total of 479 individual pollinators. Honey bees represented 94.6% of all pollinators observed. To assess pollinator movement across the crop, 140 individual flower visitors were followed over a five-day period in 2014 and again in 2015 across three orchards. Bumble bees moved further within the orchard and visited more trees per minute than foraging honey bees, while silvereyes visited more than twice as many flowers per minute than any other insect flower visitor.
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González, Eugenia, and Turner B. Sutton. "Population Diversity within Isolates of Colletotrichum spp. Causing Glomerella Leaf Spot and Bitter Rot of Apples in Three Orchards in North Carolina." Plant Disease 88, no. 12 (December 2004): 1335–40. http://dx.doi.org/10.1094/pdis.2004.88.12.1335.
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The population diversity within isolates of Glomerella cingulata and Colletotrichum spp. associated with Glomerella leaf spot and bitter rot of apples was studied in an orchard of cv. Granny Smith located in Wilkes County, NC, and one orchard each of cultivars Granny Smith and Gala located in Lincoln County, NC. Morphological characters and vegetative compatibility groups (VCGs) were used to determine diversity within the species. The relative frequencies of the morphological types found within each species in each orchard were also determined. G. cingulata was the predominant species associated with bitter rot in the three orchards and Glomerella leaf spot in the Gala orchard. In the three orchards, different morphological types were observed within isolates of G. cingulata and Colletotrichum acutatum, but not within isolates of Colletotrichum gloeosporioides. Isolates of C. gloeosporioides were not found in the orchard of cv. Granny Smith in Lincoln County. In the other two orchards, C. gloeosporioides represented the lowest proportion of the population. Three VCGs were found among isolates of G. cingulata (VCG-1, 2, and 6), two among isolates of C. gloeosporioides (VCG-9 and 10), and two among isolates of C. acutatum (VCG-15 and 16). VCGs 2, 6, 9, 10, 15, and 16 were found in the Granny Smith orchard in Wilkes County, VCGs 1, 2, and 6 in the Gala orchard in Lincoln County, and VCGs 2 and 6 in the Granny Smith orchard in Lincoln County. Differences in frequencies among the different morphological types found within the three orchards remained relatively similar throughout the season and from year to year, suggesting that the relative frequencies of G. cingulata, C. gloeosporioides, and C. acutatum remain stable in an orchard once the fungi are established.
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Dafny-Yelin, Mery, Jehudith Clara Moy, Raphael A. Stern, Israel Doron, Miriam Silberstein, and Daphna Michaeli. "High-density ‘Spadona’ pear orchard shows reduced tree sensitivity to fire blight damage due to decreased tree vigour." Phytopathologia Mediterranea 60, no. 3 (November 15, 2021): 421–26. http://dx.doi.org/10.36253/phyto-12847.
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Fire blight, caused by Erwinia amylovora, is a severe disease of pear (Pyrus communis). Highly vigorous trees are more sensitive to E. amylovora damage after summer pruning. Trees grown in high-density orchards have lower vigour than those in low-density orchards, reducing required inputs for pruning and tying, and increasing per hectare yields orchard profitability. Tree damage due to fire blight was assessed in high-density pear orchards vs. the common Israeli low-density orchards. Pear trees were planted at high densities using the spindle system (2500 trees ha-1 for ‘Spadona’ and 1250 trees ha-1 for ‘Coscia’), or at low density (1000 trees ha-1) using palmeta (’Spadona’) or open vase (‘Coscia’) systems. Four years after planting, both orchards were similarly infected with fire blight (11–50 infected blossoms per tree), but 1 year after infection, trees in the high density orchard had blossoms infections in the main limbs or trunk bases compared to the low-density orchard. At 3 years after initial infection, no trees had died in the high density orchard, whereas in the low density ‘Spadona’ orchard, 10% of the trees were wilted. For the more tolerant ‘Coscia’, infection did not progress at either orchard density. These results indicate that in fire blight-susceptible pear cultivars, a high density planting system, associated with reduced tree vigour, presents a decreased risk of fire blight damage.
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Hennig, Ernest, and Dominique Mazzi. "Spotted Wing Drosophila in Sweet Cherry Orchards in Relation to Forest Characteristics, Bycatch, and Resource Availability." Insects 9, no. 3 (September 13, 2018): 118. http://dx.doi.org/10.3390/insects9030118.
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Forest vegetation is essential for the population development of the spotted wing drosophila (SWD). Yet, little is known of how the structure of surrounding forest areas influence the abundance of SWD within orchards. In this work, we use data from a field trial at five sites in Switzerland to analyse the relationship between the extent of forest area, its edge density, and its distance from the orchard with the occurrence of SWD in sweet cherry orchards in a Bayesian hierarchical model. Availability of cherries and bycatch were also included in the model to account for effects of resource availability and trap attractiveness, respectively. For all main effects and their interactions, we accounted for potential temporal changes by adding interactions with time. We found that the closer an orchard was to a forest, the more SWD were trapped within the orchard. However, the interaction of forest proximity with forest area caused a disproportionate decrease of SWD catches. Also, the within orchard variables, trap catches of other drosophilid flies and resource availability affected SWD trap catches, but their relation changed in the course of the experiment. The findings imply that reducing SWD occurrence in orchards and other crop fields requires not only the consideration of processes outside and within the host crop field, but also of temporally changing relationships between SWD and other factors.
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Sampson, Hilary J., and S. A. Weinbaum. "428 PB 165 SPATIAL AND TEMPORAL VARIATION IN ORCHARD SOIL NITROGEN EXTRACTABILITY." HortScience 29, no. 5 (May 1994): 492e—492. http://dx.doi.org/10.21273/hortsci.29.5.492e.
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Extractable soil N may be leached below the plant rooting zone. and into the ground water. Orchards devoid of actively growing winter cover crops are subject to the greatest risk of NO3- leaching during tree dormancy in California. We examined the patterns of KCl extractable NH4+ and NO3-. and potentially mineralizable N (PMN) in the top 10 cm of soil across transects (60 samples, 150 m) in 3 almond orchard systems at 5 phenological stages in 1993. Extractable N was affected both spatially and temporally by management practices (e.g. herbicide or fertilizer application) and soil temperature. PMN did not exhibit local spatial patterns; geostatistical analysis revealed a trend across the transects indicating a larger scale of soil variation. possibly resulting from land leveling. The conventionally-managed orchard without a cover crop demonstrated higher levels of extractable NH4+ and NO3- in the top 10 cm in Feb. and Nov. 1993, compared with orchards managed with organic fertilizers and winter cover crops.
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Silveira, Carlos, Arlindo Almeida, and António C. Ribeiro. "Technological Innovation in the Traditional Olive Orchard Management: Advances and Opportunities to the Northeastern Region of Portugal." Water 14, no. 24 (December 14, 2022): 4081. http://dx.doi.org/10.3390/w14244081.
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In Portugal, the olive orchard is the most representative agricultural crop and one of the most impactful on the national economy. Therefore, a production structure accompanying the technological advances in this field would be expected; however, such a structure has not yet been realized, especially within traditional systems. Thus, taking northeastern Portugal as a case study, where a great expression of traditional orchards is visible, the following aspects are addressed within this paper: the region’s biophysical framework, the olive orchard’s environmental and socio-economic importance and its current management practices and associated pressures. As a result of that assessment, which demonstrates a low level of sustainability for traditional olive orchards, mainly in terms of economic viability, the most effective and simple solution is to act appropriately on factors that interfere with the crop yield, namely, irrigation and fertilization issues. With that purpose, a multiscale precision oliviculture system is also presented that is being developed in order to support decision making in traditional olive orchard management, aiming to obtain economically efficient productions based on eco-friendly cultural practices. Throughout the entire process, it is essential to ensure stakeholder engagement, in particular, olive growers, so that they recognize the effectiveness of potential measures that may avoid the reconversion/abandonment of the traditional olive production system.
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Manici, L. M., M. Kelderer, F. Caputo, F. Nicoletti, F. De Luca Picione, and A. R. Topp. "Impact of cover crop in pre-plant of apple orchards: relationship between crop health, root inhabiting fungi and rhizospheric bacteria." Canadian Journal of Plant Science 95, no. 5 (September 2015): 947–58. http://dx.doi.org/10.4141/cjps-2015-013.
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Manici, L. M., Kelderer, M., Caputo, F., Nicoletti, F., De Luca Picione, F. and Topp A. R. 2015. Impact of cover crop in pre-plant of apple orchards: relationship between crop health, root inhabiting fungi and rhizospheric bacteria. Can. J. Plant Sci. 95: 947–958. Replant disease of fruit tree orchards has a multifactorial etiology, mainly due to the decline in soil biodiversity along with an increase in root rot pathogens, which can be principally countered with appropriate cropping practices. Therefore, a study on the impact of cover crops on plant health of young fruit trees in long-term orchards was performed. Bioassays were performed over two consecutive growing cycles using soil from a multigeneration apple orchard affected by replant disease. First, a cycle was performed with three cover crops (alfalfa, barley, marigold) and apple rootstock plantlets; at the end, the above-ground part of the plant was removed and root residues left in the soil. In the second cycle, an apple orchard planting was simulated upon the first experimental design. Changes of diversity and composition of root inhabiting fungi and rhizospheric bacteria were evaluated as well as apple plant growth response to the pre-plant treatments. Results suggest that one cycle with alternate plants was sufficient to induce changes at the rhizosphere level, despite soil microbial resilience caused by the same long-term soil management. Rhizospheric bacteria were generally affected by plant genotype. Findings suggest that all three different cover crops can harbor almost all fungal species that colonize apple in replanted orchards (Fusarium spp., Pythum spp., binucleate Rhizoctonia sp., Cylindrocarpon-like-fungi and a several nonpathogenic saprophytic fungi named “other”), but their infection frequency varied according to the host plant. A single pre-plant break treatment did not overall differ significantly in plant growth of subsequent apple tree; however, break with marigold, which increased abundance of nonpathogenic root inhabiting fungi more than other cover crops, gave significantly higher plant growth than obtained after barley. This study provides evidence about cover-crop potential to increase soil diversity in long-term permanent cropping systems and to manipulate root colonizing fungi involved in crop health.
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Dallot, Sylvie, Tim Gottwald, Gérard Labonne, and Jean-Bernard Quiot. "Factors Affecting the Spread of Plum pox virus Strain M in Peach Orchards Subjected to Roguing in France." Phytopathology® 94, no. 12 (December 2004): 1390–98. http://dx.doi.org/10.1094/phyto.2004.94.12.1390.
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We evaluated the impact of roguing on the spread and persistence of the aggressive Plum pox virus strain M (PPV-M) in 19 peach orchard blocks in Southern France. During a 7- to 10-year period, orchards were visually inspected for PPV symptoms, and symptomatic trees were removed every year. Disease incidence was low in all orchards at disease discovery and was <1% in 16 of the 19 orchard blocks. The spread of Sharka disease was limited in all 19 blocks, with an annual disease incidence between 2 and 6%. However, new symptomatic trees were continuously detected, even after 7 to 10 years of uninterrupted control measures. An extended Cox model was developed to evaluate to what extent tree location, orchard characteristics, environment, and disease status within the vicinity influenced the risk of infection through time. Eleven variables with potential effect on tree survival (i.e., maintenance of a tree in a disease- free status through time) were selected from survey data and databases created using a geographical information system. Area of the orchard, density of planting, distance of a tree from the edge of the orchard block sharing a boundary with another diseased orchard, and distance to the nearest previously detected symptomatic tree had a significant effect on the risk for a tree to become infected through time. The combined results of this study suggest that new PPV-M infections within orchards subjected to roguing resulted from exogenous sources of inoculum, disease development of latent infected trees, as well as infected trees overlooked within the orchards during visual surveys. A revision of the survey and the roguing procedures used for more effective removal of potential sources of inoculum within the orchards and in the vicinity of the orchards would improve disease control suppression of PPV.
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Liang, Chenxin, Qiting Huang, Si Wang, Cong Wan, Qiangyi Yu, and Wenbin Wu. "Identification of citrus orchard under vegetation indexes using multi-temporal remote sensing." Advances in Modern Agriculture 3, no. 1 (June 29, 2022): 2053. http://dx.doi.org/10.54517/ama.v3i1.2053.
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<p>Citrus is widely planted in southern China. Due to cloudy and rainy weather, complex planting types, and other factors, it is difficult to use spectral information to directly identify citrus orchard information. Based on the unique phenological characteristics of citrus, this study put forward the hypothesis that “the vegetation information of citrus orchards may be weakened during the growth and expansion of citrus fruit”. According to this feature, a method of citrus orchard information identification is proposed, and the threshold of the key time window is determined. Taking Wuming District, Nanning City, and Guangxi Zhuang Autonomous Region as the research area, an empirical study on remote sensing identification of citrus orchard information is carried out. First, multi-temporal Sentinel-2 remote sensing images of the study area in 2018 were obtained, and a normalized difference vegetation index was constructed. NDVI, Green Normalized Difference Vegetation Index (GNDVI), Difference Vegetation Index (DVI), Sentinel-derived red-edge spectral indices (RESI), and other vegetation spectral indices Secondly, according to the ground sample point information, the difference in remote sensing vegetation information of different vegetation types in different periods was compared, and then the optimal features of citrus orchard identification were determined. The results showed that there was no significant difference in spectral characteristics between citrus orchards and other major crop types in the study area (such as sugarcane, banana, corn, rice, etc.), but the multi-temporal remote sensing vegetation index of the study area showed that the NDVI of citrus orchards in October was 0.47 lower than that of November, which was significantly lower than that of other crop types. In October, the GNDVI of the citrus orchard also showed a low value of 0.43, but the difference was not obvious compared with other months. However, the dispersion degree of citrus orchard DVI was low, and the separation was not strong. According to the crop phenological calendar, the period of rapid expansion of citrus fruits was from September to October, which verified the scientific hypothesis proposed in this study that the vegetation information of citrus orchards would be weakened during this period. The dispersion degree of different vegetation indexes in the citrus fruit expansion stage was obviously different, and the dispersion degree of NDVI was the highest, and the difference was the strongest. According to the phenological characteristics of the citrus orchard NDVI in October, to further build the normalized index, by using the threshold value method to identify the spatial distribution of the citrus orchard, the identification method had an overall accuracy of 82.75%, better than other identification results of vegetation index. The results of the study for citrus orchard information and remote sensing identification research provide better support for theory and practice.</p>
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Reginato, Gabino, Terence Robinson, and Victor Garcia de Cortazar. "Predicted Crop Value for a Cling Peach and Three Nectarines of Different Harvest Seasons as a Function of Crop Load." HortScience 41, no. 4 (July 2006): 995C—995. http://dx.doi.org/10.21273/hortsci.41.4.995c.
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Several field experiments to assess the effect of tree size and crop load on fruit size and yield were conducted in a `Ross' cling peach orchard and in three nectarine orchards of different harvest seasons in Chile. Trees were randomly selected in each orchard and then hand-thinned at the beginning of pit hardening to a wide range of crop loads. The fraction of above-canopy photosynthetically active radiation intercepted by the canopy (PARi) was determined at harvest and all fruits were counted, weighted, and average fruit weight calculated. Cropload and yield were expressed in terms of fraction of PARi. Data on farm gate prices for export fruit of different sizes and export dates were obtained from a Chilean export company. For each orchard, the relationship between cropload and fruit size or cropload and yield efficiency was assessed by regression analysis. Fruit size distribution was calculated from adjusted fruit size assuming a normal fruit size distribution and valued according to shipment date and price. Using crop load as a covariate, fruit size adjusted for cropload was calculated for each nectarine orchard. Differences in adjusted fruit size and yield efficiency were detected among cultivars. Predicted crop value, normalized in terms of PARi intercepted, was calculated for all the cultivars. Large differences in predicted crop value were found for early, mid-season, and late-ripening nectarines. The early and late ripening cultivars showed the highest predicted crop value, especially at lower crop loads and larger fruit sizes. On the other hand, `Ross' cling peach showed its highest crop value at a medium crop load with high yield and relatively small fruit size. (Funded by FONDECYT grant 1930695.)
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Liu, Ying, Yawen Zhang, Tianhao Xiao, Yuguo Wu, Yuan Li, Ji He, Yangzhou Xiang, and Bin Yao. "Effect of Intercropping on Fruit Yield and Financial Benefits of Rosa roxburghii Tratt Orchard in Southwest China." Agronomy 13, no. 12 (November 29, 2023): 2953. http://dx.doi.org/10.3390/agronomy13122953.
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The practice of intercropping in Rosa roxburghii Tratt orchards holds potential for enhancing fruit yield and financial benefits, yet remains insufficiently explored. To address this, we delved into the effects of intercropping on fruit yield and financial viability of R. roxburghii orchards in Longli County, southern China. Orchards of varying ages (4 years old and 5 years old; 7 years old and 8 years old) were subjected to different treatments: (i) Zea mays and Capsicum annuum intercropping, and clean tillage for younger orchards, and (ii) Lolium perenne, natural grass, and clean tillage for older orchards. Each treatment was assessed for its impact on fruit yield and financial benefits. In younger orchards, intercropping with Z. mays and C. annuum did not significantly elevate fruit yield compared to clean tillage in the 4-year-old orchard; however, C. annuum intercropping significantly improved fruit yield in the 5-year-old orchard. Concurrently, intercropping significantly augmented the total financial benefit by 9234.35–10,486.25 CNY ha−1 (Z. mays) and 14,304.90–16,629.18 CNY ha−1 (C. annuum) compared to clean tillage. In older orchards, L. perenne intercropping significantly elevated fruit yield by 598.84–803.64 kg·ha−1, while natural grass reduced it by 394.61–986.24 kg·ha−1, compared to clean tillage. Additionally, L. perenne intercropping significantly boosted the total financial benefit by 8873.92–9956.56 CNY ha−1, whereas natural grass negatively impacted financial benefits by 78.42–2444.94 CNY ha−1 compared to clean tillage. Collectively, our results illustrate that judicious selection of intercrops, based on orchard age and conditions, can significantly enhance both fruit yield and financial advantages in R. roxburghii orchards. This study furnishes vital insights for orchard management and accentuates the prospective merits of intercropping in fruit production systems.
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Logan, D. P., B. J. Maher, and P. G. Connolly. "Increased numbers of earwigs (Forficula auricularia) in kiwifruit orchards are associated with fewer broadspectrum sprays." New Zealand Plant Protection 64 (January 8, 2011): 49–54. http://dx.doi.org/10.30843/nzpp.2011.64.5955.
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European earwigs are sensitive to the residues of broadspectrum insecticides More earwigs are found on organicallymanaged than on conventionallymanaged kiwifruit orchards Since 2007 there have been changes in insecticide use on kiwifruit orchards In particular the broadspectrum insecticide diazinon was replaced by socalled reducedrisk insecticides In the current study earwig numbers were measured in nine conventionallymanaged and seven organicallymanaged orchards for 4 years (200607 to 200910) Numbers of earwigs on orchard blocks under organic management did not differ between years and were initially higher than on conventionallymanaged orchard blocks There was a trend for earwig numbers to increase on conventionallymanaged orchard blocks Earwig abundance decreased by approximately 60 with each spray application after allowing for differences between years
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McLaren, G. F., and P. A. Alspach. "The incidence of New Zealand flower thrips in stonefruit orchards between flowering and harvest." New Zealand Plant Protection 59 (August 1, 2006): 63–68. http://dx.doi.org/10.30843/nzpp.2006.59.4527.
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New Zealand flower thrips Thrips obscuratus (Crawford) (NZFT) feeds on the nectar and pollen of stonefruit flowers and was thought to then disappear from orchards for 23 months until the fruit ripen Aerial populations of NZFT were sampled in Central Otago orchards using white sticky traps Samples were taken in a peach orchard for 6 months from flowering until after harvest and in two cherry orchards for six weeks during harvest In all three orchards populations of NZFT reached high numbers in December In the peach block NZFT numbers peaked in December several weeks before the fruit began to ripen It was concluded that NZFT can live in stonefruit orchards probably feeding on newly emerged leaves of peaches or cherries or in the vegetation of the irrigated orchard floor Trapped thrips could also have come from other blocks within the larger orchard areas or from outside sources
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Giacalone, Giovanna, Cristiana Peano, Deborah Isocrono, and Francesco Sottile. "Are Cover Crops Affecting the Quality and Sustainability of Fruit Production?" Agriculture 11, no. 12 (November 29, 2021): 1201. http://dx.doi.org/10.3390/agriculture11121201.
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The study of the interaction between fruit trees and cover crops has been addressed in numerous works over the last 50 years or more, evidencing the need to evolve from a productive orchard to an orchard that plays different ecosystem roles in terms of environmental sustainability rather than just productivity. This review, through an analysis of the scientific literature since the 1950s, highlights the development of sustainable soil management models in fruit tree orchards, mostly considering the relationship with fruit quality traits and with the ecosystem services that result from the adoption of cover crops, aiming at identifying and formulating technical recommendations in perennial orchards. Cover crop management surely improves soil features and positively influences fruit quality in perennial woody species, but also helps to develop a better habitat for beneficial insects, thus influencing pollination. A large number of scientific approaches highlight the beneficial use of a mixture of seeds in order to enhance biodiversity, aiming at improving ecosystem services for a transition towards more sustainable systems based on agroecological management.
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Sritongchuay, Tuanjit, Claire Kremen, and Sara Bumrungsri. "Effects of forest and cave proximity on fruit set of tree crops in tropical orchards in Southern Thailand." Journal of Tropical Ecology 32, no. 4 (July 2016): 269–79. http://dx.doi.org/10.1017/s0266467416000353.
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Abstract:Deforestation and forest fragmentation are contributing to declines in crop pollinator populations worldwide. Several studies have examined the impact of forest proximity on plant pollination ecology, but concentrated on single crop species. However, it can be more informative to investigate multiple crop and pollinator species in a community, because different pollinator groups may respond differently to forest distance. We evaluated flower visitor diversity, visitation frequency, and fruit set for three crop species (rambutan, durian and mango) in 10 pairs of mixed fruit orchards. Each pair consisted of one orchard near to (< 1 km) and one orchard far from (> 7 km) the forest edge. Rambutan fruit set was significantly influenced by distance to forest. The main visitors of rambutan flowers were stingless bees. In contrast, the dominant visitors to durian and mango flowers were nectarivorous bats and flies, respectively, and the fruit set of these crops were not significantly influenced by distance to forest. However, durian fruit set was negatively affected by distance to the nearest cave inhabited by nectarivorous bats. This study demonstrates that both caves and forests can be important pollinator sources for agricultural crops, and that the dispersal success of pollinators is related to isolation from source habitats. Maintaining forest patches and limestone karsts may provide stepping stones across fragmented landscapes, and attract greater numbers of pollinators to agricultural areas.
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Rizzo, D. M., E. C. Whiting, and R. B. Elkins. "Spatial Distribution of Armillaria mellea in Pear Orchards." Plant Disease 82, no. 11 (November 1998): 1226–31. http://dx.doi.org/10.1094/pdis.1998.82.11.1226.
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Pears have traditionally been considered to be highly resistant to Armillaria root disease (causal agent: Armillaria mellea). In recent years, however, the incidence of Armillaria root disease in pears has increased in California. To determine the spatial distribution of Armillaria root disease in the field, a total of 156 isolates of Armillaria were collected from dead and dying pear trees located within two orchards in Lake County. All isolates from these two orchards, as well as from an additional 10 pear orchards, were identified as Armillaria mellea sensu stricto. Based on pairings among 102 Armillaria isolates, four somatic incompatibility groups (SIGs) were identified at orchard 1. Three of the four SIGs at this site were over 100 m in length; the largest SIG was at least 200 m in length. Pairings among 54 isolates identified five SIGs at orchard 2. The SIGs at orchard 2 were generally smaller than those detected at orchard 1 and ranged from 20 to 60 m in length. The size of the SIGs points toward long-term establishment of the fungus on the two sites, most likely predating the establishment of the pear orchards. Extensive root excavations of 19 trees indicated that the primary means of secondary spread of Armillaria was via rhizomorphs, as opposed to root-to-root contact.
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Guo, Li-Yun, Themis J. Michailides, and David P. Morgan. "Survival of Mucor piriformis in Soil of Apple Orchards in California." Plant Disease 83, no. 2 (February 1999): 189–93. http://dx.doi.org/10.1094/pdis.1999.83.2.189.
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Four apple orchards were sampled periodically in 1995 and 1996 to determine the population levels of Mucor piriformis, the causal agent of Mucor rot. The highest population, 119 propagules of M. piriformis per g of dry soil, occurred during winter. Populations declined during summer and fall and increased again in winter and early spring of the following year. Isolates from soil and apple fruit of these orchards contained +, −, and neuter mating types, with the + being the predominant mating type. Depending on the orchard, up to 27.7% of apples infected by M. piriformis had zygospores developed on them. The time of increase in M. piriformis populations corresponded with postharvest drop and decay of apples on the orchard floor. Experiments were carried out to compare changes in M. piriformis populations in soil with intact fruit left on the orchard floor, sliced fruit, or after removal of fruit from the orchard. The greatest numbers of M. piriformis occurred in soil with apple pieces, followed by soil with intact apples, and the lowest in soil without apples. Results suggest that the best time to sample soils to determine the occurrence of M. piriformis in California apple orchards is from January to March, and practices of flail-mowing the orchard floor after harvest may increase population levels of M. piriformis in soil.
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Ben-Hamo, Miriam, David Ezra, Helena Krasnov, and Lior Blank. "Spatial and Temporal Dynamics of Mal Secco Disease Spread in Lemon Orchards in Israel." Phytopathology® 110, no. 4 (April 2020): 863–72. http://dx.doi.org/10.1094/phyto-06-19-0195-r.
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Mal Secco is a severe disease of citrus in which the fungus Plenodomus tracheiphilus (formerly Phoma tracheiphila) penetrates the vascular system of the host. In this study, we characterized the spatial dynamics of the disease in seven lemon orchards. A representative block of trees from each orchard was evaluated monthly during 3 consecutive years. In addition, scouts assessed disease severity in 75 orchards from three different geographical regions and tested for association between disease severity and measures of orchard management, environmental factors, cultural practices, and cultivar type. We assessed disease incidence and characteristics of spatial patterns using Ripley’s K function and fitted logistic regression models for different neighboring tree structures followed by model selection methods to provide insight into the spatial and temporal dynamics of disease progress. We found different rates of disease spread in different orchards, which are most likely the result of differences in orchard management practices or less likely the result of differences in climatic conditions. There was an indication that agricultural tools contribute to spread of the disease within rows of trees. The results confirm that the lemon cultivar Interdonato is less susceptible compared with other citrus cultivars, and they suggest that the density of urban terrain surrounding each orchard is positively correlated with the severity of the disease. In contrast to our expectations, no correlation was found between the density of lemon orchards surrounding an orchard and the severity of the disease within it, which corroborates previous findings regarding the limited distribution of the disease.
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Lei, Xiaohui, Quanchun Yuan, Tao Xyu, Yannan Qi, Jin Zeng, Kai Huang, Yuanhao Sun, Andreas Herbst, and Xiaolan Lyu. "Technologies and Equipment of Mechanized Blossom Thinning in Orchards: A Review." Agronomy 13, no. 11 (October 31, 2023): 2753. http://dx.doi.org/10.3390/agronomy13112753.
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Orchard thinning can avoid biennial bearing and improve fruit quality, which is a necessary agronomic section in orchard management. The existing methods of artificial fruit thinning and chemical spraying are no longer suitable for the development of modern agriculture. With the continuous acceleration of the construction process of modern orchards, blossom thinning mechanization has become an inevitable trend in the development of the orchard flower and fruit management. Based on relevant reports in the past 20 years, the paper discusses the current level of development of mechanized blossom thinning technologies and equipment in orchards from three aspects: mechanism research, machine development, and intelligent upgrading. Firstly, for thinning mechanism research, three directions were investigated: the rope flexible hitting force, thinning agronomic requirements, and the fruit tree growth model between thinning and fruit yields. Secondly, for marketable machine developments, two types of machines were investigated: the hand-held thinner and tractor-mounted thinner. The hand-held thinner is mainly suitable for traditional old orchards with a messy canopy structure, especially in the interior and top of the canopy. The tractor-mounted thinner is mainly suitable for orchards with the same crown structure, such as the hedge type, trunk type, and V-type. Thirdly, for equipment intelligent upgrading, the research of the intelligent detection algorithm for inflorescence on the fruit tree was investigated, for species including the apple, pear, citrus, grape, litchi, mango, and apricot. Finally, combining the advantages and disadvantages of the research, the authors propose thoughts and prospects, which can provide a reference for the design and applications of orchard mechanized blossom thinning.
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Caron, G. É. "Seed-cone and pollen-cone production models for young black spruce seedling seed orchards: a first approximation." Canadian Journal of Forest Research 25, no. 6 (June 1, 1995): 921–28. http://dx.doi.org/10.1139/x95-101.
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Seed orchard managers wanting to predict potential seed-cone (Sc) and pollen-cone (Pc) production 1 year in advance of seed release and pollen dissemination need predictive models. The present study proposes the use of cone-crop models based on tree age in young black spruce (Piceamariana (Mill.) B.S.P.) orchards. Sc and Pc production was monitored from 1987 to 1993 in each of five seedling seed orchards. Some trees began bearing Sc and Pc by tree age 6. The relationships of Sc and Pc production with tree age were each represented by three sigmoid equations: one for light crop years, one for heavy crop years, and one for light plus heavy crop years. The rate of cone increase for heavy and light crop years differed for both Sc and Pc. Sigmoid equations representing heavy Sc and Pc crop years in orchards had the highest r2 (0.8462 and 0.9381, respectively) and the lowest standard error. Sigmoid model of heavy crop years with plantation data also had the highest r2 value (0.8066) and the lowest standard error. The rate of Sc and Pc increase versus tree age was higher for orchards than for plantations. To select the best of three sigmoid models, one must take into account the early buildup phase of cone production in young trees, the yearly fluctuation in cone crops, previous-year cone production, and environmental factors that can affect cone crops.
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Huang, Li-Sha, Jiayin Song, Yan-Qiang Sun, Qiong Gao, Si-Qian Jiao, Shan-Shan Zhou, Yuqing Jin, et al. "Pollination dynamics in a Platycladus orientalis seed orchard as revealed by partial pedigree reconstruction." Canadian Journal of Forest Research 48, no. 8 (August 2018): 952–57. http://dx.doi.org/10.1139/cjfr-2018-0077.
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Pollination dynamics was studied in a first-generation Platycladus orientalis (L.) Franco seed orchard with pedigree reconstruction using eight nuclear and four chloroplast SSRs. The pedigree reconstruction assigned 371 of 448 studied seeds to one of the orchard’s 192 candidate male parents and showed a high level of outcrossing and pollen contamination in the orchard’s seed crop. While the orchard’s seed population showed greater allelic richness compared with the parental population, a few alleles present in the parental population were missing in the seed crop. Additionally, we detected no significant correlation between male reproductive energy (pollen yield) and male reproductive success; however, uneven parental contribution was also observed. Pollen management practices were recommended to ensure the maintenance of genetic diversity in the seed crops and increase in genetic gain.
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Shaw, P. W., D. R. Wallis, and D. J. Rogers. "The impact of early season insecticides on biological control of apple leafcurling midge (Dasineura mali)." New Zealand Plant Protection 56 (August 1, 2003): 164–67. http://dx.doi.org/10.30843/nzpp.2003.56.6036.
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The fate of apple leafcurling midge (ALCM Dasineura mali) egg batches was monitored in spring 2003 at two apple orchards in Riwaka near Motueka Orchard A had received prebloom insecticide applications of chlorpyrifos and carbaryl for fruit thinning each season since 2000 Orchard B substituted these chemicals with the selective insecticide buprofezin and used benzyladenine for fruit thinning over the same period Predation and parasitism of ALCM eggs at orchard B resulted in lower survival of larvae and less damage to shoots compared to orchard A Ninety percent of ALCM larvae at orchard B were parasitised by Platygaster demades compared with only 3 at orchard A Heavy infestation of shoots by second generation midge larvae at orchard A resulted in premature termination of 69 of growing shoot tips These results suggest that nonselective early season insecticides used in pipfruit spray programmes may disrupt biological control of ALCM
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Sousa, Miguel L., Marta Gonçalves, Délia Fialho, António Ramos, João P. Lopes, Cristina M. Oliveira, and J. Paulo De Melo-Abreu. "Apple and Pear Model for Optimal Production and Fruit Grade in a Changing Environment." Horticulturae 8, no. 10 (September 22, 2022): 873. http://dx.doi.org/10.3390/horticulturae8100873.
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Apple and pear crops are very important to the rural economy of Portugal. Despite significant improvements in productivity and quality, due to the introduction of new management techniques, model-based decision support may further increase the revenue of the growers. Available simulation models of orchard growth and production are scarce and are often highly empirical. This study presents a mechanistic model for the simulation of productivity and fruit grade of apple and pear orchards under potential and water-limited conditions. The effects of temperature extremes and rain on fruit set are addressed. The model was validated on apple and pear datasets derived from extensive experiments conducted in Central and Southern Portugal. Model performance is high and depicts the effect of crop load on productivity and fruit-size grade and the distribution of both crops. A simulation example shows the relationship between productivity and average fruit size for a hypothetical six-year-olc apple orchard. The model herewith presented is a tool that can be used to estimate optimal crop load for maximum revenue and productivity, fruit size distribution, water use, and other variables relevant for pome fruit production.
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Brinkhoff, James, and Andrew J. Robson. "Macadamia Orchard Planting Year and Area Estimation at a National Scale." Remote Sensing 12, no. 14 (July 13, 2020): 2245. http://dx.doi.org/10.3390/rs12142245.
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Accurate estimates of tree crop orchard age and historical crop area are important to develop yield prediction algorithms, and facilitate improving accuracy in ongoing crop forecasts. This is particularly relevant for the increasingly productive macadamia industry in Australia, where knowledge of tree age, as well as total planted area, are important predictors of productivity, and the area devoted to macadamia orchards is rapidly increasing. We developed a technique to aggregate more than 30 years of historical imagery, generate summary tables from the data, and search multiple combinations of parameters to find the most accurate planting year prediction algorithm. This made use of known planting dates of more than 90 macadamia blocks spread across multiple growing regions. The selected algorithm achieved a planting year mean absolute error of 1.7 years. The algorithm was then applied to all macadamia features in east Australia, as defined in an recent Australian tree crops map, to determine the area planted per year and the total cumulative area of macadamia orchards in Australia. The area estimates were refined by improving the resolution of the mapped macadamia features, by removing non-productive areas based on an optimal vegetation index threshold.
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Osipitan, O. Adewale, Bahar Yildiz-Kutman, Seth Watkins, Patrick H. Brown, and Bradley D. Hanson. "Impacts of repeated glyphosate use on growth of orchard crops." Weed Technology 34, no. 6 (August 18, 2020): 888–96. http://dx.doi.org/10.1017/wet.2020.85.
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AbstractGlyphosate is an important component of herbicide programs in orchard crops in California. It can be applied alone or in tank-mix combinations under the crop rows or to the entire field and often is used multiple times each year. There has been speculation about the potential impacts of repeated use of glyphosate in perennial crop systems, because of uptake from shallow root systems or indirectly because of effects on nutrient availability in soil. To address these concerns, research was conducted from 2013 to 2020 on key orchard crops to evaluate tree response to glyphosate regimens. Almond, cherry, and prune were evaluated in separate experiments. In each crop, the experimental design was a factorial arrangement of two soil types, four glyphosate rates (0, 1.1, 2.2, and 4.4 kg ae ha−1, applied three times annually), and two post-glyphosate application irrigation treatments. In the first 2 yr of the study, there was no clear impact of the glyphosate regimens on shikimate accumulation or leaf chlorophyll content, which suggested no direct effect on the crop. In the seventh year of the study, after six consecutive years of glyphosate application to the orchard floors, there were no negative impacts of glyphosate application on leaf nutrient concentration or on cumulative trunk growth in any of the three orchard crops. Lack of a negative growth impact even at the highest treatment rate, which included 18 applications of glyphosate totaling nearly 80 kg ae ha−1 glyphosate over the course of the experiment suggest there is not likely a significant risk to tree health of judicious use of the herbicide in these production systems. Given the economic importance of orchard crops in California, and grower and industry concerns about pesticides generally and specifically about glyphosate, these findings are timely contributions to weed management concerns in perennial specialty crops.
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Nagy, Péter Tamás. "Makro- és mikroelem-tartalom összehasonlítása almaültetvények talajában." Agrokémia és Talajtan 54, no. 3-4 (September 1, 2005): 389–402. http://dx.doi.org/10.1556/agrokem.54.2005.3-4.10.
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In a three-year study carried out at the Debrecen-Pallagi nursery of the University of Debrecen, the nutrient contents, humus content and pH of the soil were determined in integrated and organic apple orchards established on brown forest soil with thin interstratified layers of colloid and sesquioxide accumulation. The organic orchard was only given organic manure (50 t/ha) in spring 2000 and 2002, while the integrated orchard was treated with 250 kg/ha complex NPK fertilizer (16.5-16.5-16.5) every year between 1997 and 2003 after the leaves had fallen. An additional 50 kg/ha N active agent as NH 4 NO 3 was applied every year, while 4 t/ha lime fertilizer (carbonation mud) was provided in autumn 2002 and 25 t/ha organic manure in November 2003. In 2004 no fertilizer was given to either orchard. The available forms of N (NO 3- , NH 4+ , organic N and total N) and P (ortho-, organic and total-PO 43- ) were determined after extraction with 0.01 M CaCl 2 , while the Ca, Mg and microelement (Mn, Cu, Zn) content of the soil was extracted with NH 4 -acetate +EDTA (Lakanen-Erviö extractant). Potassium was measured in both extractants. The results showed that the inorganic, organic and total soluble nitrogen in the soil were significantly higher (P = 0.05) in the integrated orchard than in the organic one. It was found that the quantity and ratio of the organic N fraction was comparable with that of the inorganic N forms. The ortho- phosphate and total P fractions were significantly higher (P = 0.05) in the integrated apple orchard than in the organic orchard, while there was no significant difference in the organic P quantity. The potassium data showed that both the integrated and organic orchards contained a satisfactory amount of adsorbed K in spite of the poor colloid content and high soil acidity. The Ca, Mg, Co and Zn contents of the integrated soils were significantly higher (P = 0.05) than in the organic orchard. For Mn, however, no substantial difference was found between the integrated and organic orchards. With the exception of Mn, the nutrient concentrations reflected the differences in the nutrient management of the integrated and organic apple orchards.
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Ahmad Anas Yusof, Mohd Khairi Mohamed Nor, Nur Latif Azyze Mohd Shaari Azyze, Anuar Mohamed Kassim, Shamsul Anuar Shamsudin, Hamdan Sulaiman, and Mohd Aswad Hanafi. "Land Clearing, Preparation and Drone Monitoring using Red-Green-Blue (RGB) and Thermal Imagery for Smart Durian Orchard Management Project." Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 91, no. 1 (January 17, 2022): 115–28. http://dx.doi.org/10.37934/arfmts.91.1.115128.
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Malaysia's agricultural activity is progressing toward the use of precision agriculture and Internet of Things (IoT) technology as the country moves forward with the adoption of Industrial Revolution 4.0. As a result, a novel approach based on spatial and thermal analysis is proposed and presented, along with a low-cost thermal and photogrammetric modelling workflow. As a result, the purpose of this project is to monitor durian orchards using drones equipped with thermal and red-green-blue (RGB) digital cameras. Thermal maps are presented to demonstrate the relationship between vegetation and soil temperature, and digital imagery from an early stage of preparation in the orchard is analysed for overall management system improvement. The findings indicate that the uneven ground surface of the orchard may have an effect on the irrigation system and crop yield production. Thermal imaging also reveals variations in soil temperature that are related to soil humidity. A well-managed orchard is essential for ensuring that the crop grows in a healthy state. The data acquisition and processing part of this workflow are being tested in Alor Gajah Smart Durian Orchard Management Project, Melaka, Malaysia.
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Mauro, Rosario Paolo, Umberto Anastasi, Sara Lombardo, Gaetano Pandino, Roberto Pesce, Restuccia Alessia, and Giovanni Mauromicale. "Cover crops for managing weeds, soil chemical fertility and nutritional status of organically grown orange orchard in Sicily." Italian Journal of Agronomy 10, no. 2 (June 23, 2015): 101. http://dx.doi.org/10.4081/ija.2015.641.
Full textAbstract:
Cover crops can offer significant advantages in the agronomic management of citrus orchards in Mediterranean environments. Therefore, a three-year research was conducted in eastern Sicily aimed at studying the effects of four cover crop sequences (<em>Sinapis arvensis-Trigonella foenum-graecum-T. foenum-graecum</em>; <em>Medicago scutellata-Avena sativa-Lolium perenne</em>; V<em>icia faba minor-A. sativa-A. sativa</em>; <em>A. sativa-V. faba. minor-L. perenne</em>) on weeds, major soil chemical properties and nutritional status of an organically grown orange orchard. The results highlighted that, among the studied cover crop sequences, <em>Vicia faba-Avena-Avena</em> was the most beneficial for weeds control within the orchard (92%, of cover crop cover, and 586 and 89 g DW m<sup>–2</sup> of cover crop aboveground biomass and weeds aboveground biomass, respectively). Overall, the chemical fertility of the soil was positively influenced. In particular, it was observed an increase of the content of total nitrogen and available phosphorus in the soil by both <em>Sinapis-Trigonella-Trigonella</em> (0.75 g kg<sup>–1</sup> and 59.0 mg kg<sup>–1</sup>, respectively) and <em>Vicia faba-Avena-Avena</em> (0.70 g kg<sup>–1</sup> and 56.0 mg kg<sup>–1</sup>, respectively) cover crop sequences. <em>Medicago-Avena-Lolium</em> sequence seemed to be the most useful to ensure a better nutritional status of the orange orchard.
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Byram, T. D., W. J. Lowe, and J. A. McGriff. "Clonal and Annual Variation in Cone Production in Loblolly Pine Seed Orchards." Forest Science 32, no. 4 (December 1, 1986): 1067–73. http://dx.doi.org/10.1093/forestscience/32.4.1067.
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Abstract Monitoring two loblolly pine (Pinus taeda L.) orchards for several years indicated that cone production was under moderate genetic control (broad-sense heritability estimates of 0.35 and 0.40). Early in the life of these orchards a few clones contributed most of the cone crop. This percentage was reduced as the orchards matured until approximately 60% of the clones were required to produce 90% of the cone crop. Even then, clones frequently changed rank from year to year. There was no relationship between a clone's cone production in a seed orchard and its performance in progeny tests. Forest Sci. 32:1067–1073.
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Wood, Bruce W., Jeffrey Burcaw, Michael W. Poole, and Mark T. Burnette. "OPTIMAL SPACIAL ORIENTATION OF TREE CROPS BASED ON MAXIMIZING SUNLIGHT INTERCEPTION DURING CRITICAL GROWTH AND DEVELOPMENTAL WINDOWS." HortScience 28, no. 5 (May 1993): 490d—490. http://dx.doi.org/10.21273/hortsci.28.5.490d.
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Tree crops are often planted at particular geometrical and spacing patterns with little or no quantitatively based data on how the arrangements influence sunlight interception and productivity.We have developed a mathematical model describing intertree shading derived from computer simulations of tree growth and light extinction through the canopy. Variables include tree shape, intertree spacings, orchard geometry, geographical coordinates, season, and time of day. This model predicts the extent of intertree shading during the daily interval of maximum photosynthesis for any combination of these conditions and indicates that optimal orchard design is unique for each latitude and tree crop. It can be used by the orchardist to establish orchards in which trees receive maximum levels of sunlight within specific windows of time; for example, during the period of fruit development or during the accumulation of dormant season assimilate reserves.
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SONG, ZI-WEI, YUAN ZHENG, BAO-XIN ZHANG, and DUN-SONG LI. "Study of the population dynamics of phytoseiid mites on citrus under natural conditions." Zoosymposia 22 (November 30, 2022): 267. http://dx.doi.org/10.11646/zoosymposia.22.1.166.
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Citrus is the most extensively produced tree fruit crop in the world, and the citrus red mites, Panonychus citri (McGregor) and citrus rust mites, Phyllocoptruta oleivora (Ashmead) are the serious pest mites of citrus crops. Except for chemical control, biological control is an important component of integrated pest management and plays an essential role in regulating populations of pest mites. Predatory mites from the family Phytoseiidae are important natural enemies. The populations of P. citri are usually controlled by indigenous predators, mainly the phytoseiid mites. As native phytoseiids are more likely to adapt to the local environmental conditions than the commercially available phytoseiids, conservation of local phytoseiid species is a key factor for the IPM success in citrus orchards. Investigation into the species and population dynamics of phytoseiid mites in citrus orchards will provide important references to the conservation and utilization of predatory mites. This work aimed to investigate the species of phytoseiid mites and their seasonal population dynamics associated with P. citri in different citrus cultivars orchards. We sampled phytoseiid mites from orchards planted with three citrus cultivars of citron-lemon, Ehime Kashi No. 28 and Shatangju, respectively, from April to December in 2018⁓2021. Species of phytoseiid mites, and their developmental stage and gender were identified under a microscope. In the citron-lemon orchard, we recorded nine phytoseiid species in 2018, but only three species in 2019. The dominant species was Scapulaseius newsami (Evans). In 2020, five species with a dominant species of Euseius nicholsi (Ehara et Lee) were found in Ehime Kashi No. 28 orchard, but only two with a dominant species of Neoseiulus californicus (McGregor) detected in the Shatangju orchard. In the Shatangju orchard in 2021, six species were recorded with N. californicus being dominant from April to July, and Amblyseius eharai Amitai & Swirski being dominant from August to December. The population of predatory mites peaked in May and October in the citron-lemon orchard, and in May, July and October in the Ehime Kashi No. 28 and Shatangju orchards. All active life stages (i.e., larva, nymph and adult) were found and most were adults. The sex ratio was female-biased (over 80%) in each orchard. In conclusion, the population size of phytoseiids changed over the growing seasons. Whether this could be attributed to the different tolerance capacities of different species to the local climate conditions or chemical pesticides remains for future studies.
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Lstibůrek, Milan, and Yousry A. El-Kassaby. "Minimum-Inbreeding Seed Orchard Design." Forest Science 56, no. 6 (December 1, 2010): 603–8. http://dx.doi.org/10.1093/forestscience/56.6.603.
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Abstract The industrial concept of “quadratic assignment problem” (QAP) was used to develop a new seed orchard design that minimizes the level of inbreeding (minimum inbreeding [MI]) in an orchard's seed crop through the optimum allocation of clones within the orchard's grid. Spatial distribution of individual trees was done in proportion to their degree of genetic relatedness. The MI orchard design accommodates a variable number of unrelated or related clones with equal or variable sizes, and it is not restricted by the orchard's spatial configuration (shape or size). The proposed design is suitable for advanced generation populations that commonly harbor complicated pedigree relationships. The MI design was compared with the commonly used permutated neighborhood design and the completely randomized scheme, resulting in aggregate inbreeding distances of 6.82, 12.53, and 22.56, respectively, highlighting the effectiveness of the proposed design.
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Hong, Chuanxue, Brent A. Holtz, David P. Morgan, and Themis J. Michailides. "Significance of Thinned Fruit as a Source of the Secondary Inoculum of Monilinia fructicola in California Nectarine Orchards." Plant Disease 81, no. 5 (May 1997): 519–24. http://dx.doi.org/10.1094/pdis.1997.81.5.519.
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The significance of thinned fruit as a source of secondary inoculum in the spread of brown rot, caused by Monilinia fructicola, under semi-arid weather conditions of the San Joaquin Valley in California, was investigated in seven nectarine orchards in 1995 and 1996. Between 6 and 60% (depending on the orchard) of thinned fruit showed sporulation by M. fructicola. Brown rot was significantly less severe at preharvest (five orchards) and postharvest (one orchard) on fruit harvested from trees in plots from which thinned fruit were completely removed than on those in plots from which thinned fruit were not removed. M. fructicola sporulated more frequently on thinned fruit placed into irrigation trenches than on those left on the dry berms in tree rows. The incidence of preharvest fruit brown rot increased exponentially as the density of thinned fruit increased on the orchard floor. These results suggest that thinned fruit left on the floor of nectarine orchards can be a significant inoculum source of secondary infections. Removal or destruction of thinned fruit should reduce brown rot in nectarine and possibly other stone fruit orchards under semi-arid California conditions.
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Villarino, M., P. Melgarejo, J. Usall, J. Segarra, and A. De Cal. "Primary Inoculum Sources of Monilinia spp. in Spanish Peach Orchards and Their Relative Importance in Brown Rot." Plant Disease 94, no. 8 (August 2010): 1048–54. http://dx.doi.org/10.1094/pdis-94-8-1048.
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Immediately following the identification of Monilinia fructicola in a Spanish peach orchard in the Ebro Valley in 2006, this orchard and two other orchards in the same valley were intensively sampled for potential tree and ground sources of primary Monilinia inoculum before and during three growing seasons between 2006 and 2008. Overwintered Monilinia spp. produced inoculum from only mycelium, and no apothecia were found in any of the three orchards over the three growing seasons. Mummies on trees were the main source of primary inoculum. More than 90% of Monilinia isolates on all fruit mummies were M. laxa. Positive relationships were found between (i) the number of mummified fruit and the incidence of postharvest brown rot (P = 0.05, r = 0.75, n = 8), and (ii) the number of mummified fruit and nonabscised aborted fruit in the trees and the number of conidia on the fruit surface (P = 0.04, r = 0.71; P = 0.01, r = 0.94, respectively, n = 8) and the incidence of latent infection (P = 0.03, r = 0.75; P = 0.001, r = 0.99; respectively, n = 8). In addition, the numbers of mummified fruit and pruned branches on the orchard floor were correlated with the number of airborne conidia in the orchard. Based on the results of these surveys, the control of brown rot in stone fruit orchards is discussed.
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Zhang, Mengke, Xiaoguang Li, Ling Wang, Liujian Jin, and Shubo Wang. "A Path Planning System for Orchard Mower Based on Improved A* Algorithm." Agronomy 14, no. 2 (February 18, 2024): 391. http://dx.doi.org/10.3390/agronomy14020391.
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The application of intelligent mobile robots in agriculture has emerged as a new research frontier, with the integration of autonomous navigation technology and intelligent agricultural robots being the key to the widespread adoption of smart agricultural machinery. This paper investigates comprehensive coverage path planning for tracked lawnmowers within orchard environments and addresses challenges related to task allocation and battery life. Firstly, in this study, the motion model of the tracked lawnmower was initially simplified based on assumptions about the orchard environment. Force analyses were conducted on each of its motion mechanisms. For the known orchard environment, a grid-based mapping technique was employed to model the orchard environment. Then, in order to improve the algorithm speed and reduce the number of turns during the lawnmower’s traversal, the A* search algorithm was enhanced by combining the method of robot cluster traversal in the orchard environment. Finally, the improved method was simulated and verified in the MATLAB platform to investigate the influence of the number of lawnmower clusters on the path planning in the connected and non-connected orchards. Furthermore, two sets of on-site field trials were meticulously designed to validate the reliability, practicality, and efficacy of the simulation experiments.
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Lennox, Cheryl L., Robert A. Spotts, and Louis A. Cervantes. "Populations of Botrytis cinerea and Penicillium spp. on Pear Fruit, and in Orchards and Packinghouses, and Their Relationship to Postharvest Decay." Plant Disease 87, no. 6 (June 2003): 639–44. http://dx.doi.org/10.1094/pdis.2003.87.6.639.
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The aims of this study were to examine the sources and population sizes of Botrytis cinerea and Penicillium spp. in ‘d'Anjou’ pear orchards, packinghouses, and storage, and to determine the relationship between population sizes and postharvest decay. Densities of B. cinerea ranged from nondetectable to 4.0 CFU/cm2 on fruit, nondetectable to 3.1 CFU/liter in orchard air, and nondetectable to 1,167 CFU/g in orchard litter. The majority of packinghouse air and orchard soil samples collected yielded no B. cinerea inoculum. Densities of Penicillium spp. ranged from nondetectable to 2.7 CFU/cm2 on pear fruit, nondetectable to 3.13 CFU/liter in orchard air, nondetectable to 11.8 CFU/liter in packingline air, nondetectable to 3.9 CFU/liter in cold-storage air, 38 to 431 CFU/g in orchard soil, and 131 to 1,128 CFU/g in orchard litter. The mean incidence of gray mold in stored d'Anjou pear fruit ranged from 0.7 to 10.7%. Incidence of blue mold ranged from 0 to 16.5%. Significant positive correlations were observed between decay and fruit surface populations of B. cinerea and Penicillium spp. In conclusion, inoculum levels of these important postharvest pathogens in orchard and packinghouse air, and orchard soil and litter, cannot be used as indicators of postharvest decay; whereas the inoculum level on fruit surfaces may be a useful predictor of decay.
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Wang, Zhenlei, Weiliang Zhao, and Linqiao Xi. "Alfalfa Cover Crops Influence the Soil Fungal Community and Function in Apple Orchards in Arid Desert Oases in Northwest China." Sustainability 14, no. 19 (September 20, 2022): 11816. http://dx.doi.org/10.3390/su141911816.
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The present study investigated the effects of alfalfa cover crops on soil fungal communities and function in apple orchards in arid desert oases. A five-year apple orchard was subjected to two treatments: Intercropping with an alfalfa cover crop (A) and clean tillage (QG). The soil fungal ITS (internal transcribed spacer) region was analyzed using Illumina MiSeq high-throughput sequencing technology, and fungal function was determined using FUNGuild. Changes in the fungal community structure, diversity, and metabolic function in the 0–60 cm soil layer of the apple orchard were compared. The results showed that the alfalfa cover crops enhanced fungal richness but reduced diversity. The alfalfa cover crops improved fungal copy numbers but reduced the relative abundance of the dominant phylum, Ascomycota. Correlations between soil fungi and soil factors revealed that total nitrogen and total carbon were the most important nutrient factors in positively regulating the fungal community. The main negative factors were soil total salts and pH. The FUNGuild functional prediction showed that Ectomycorrhizal-Wood Saprotroph and Endophyte-Undefined Saprotroph only appeared in the alfalfa cover crops. The abundance of endophytes was enhanced (p < 0.05), but the abundance of plant pathogens and wood saprotrophs decreased (p < 0.01). Alfalfa cover crops could increase the copy numbers and richness in arid oasis apple orchards.
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Bueno, R., and Jay D. Stone. "APHELINUS PERPALLIDUS PARASITISM OF MONELLIA CARYELLA POPULATIONS IN FAR WEST TEXAS1." Journal of Entomological Science 20, no. 3 (July 1, 1985): 325–30. http://dx.doi.org/10.18474/0749-8004-20.3.325.
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In 1981 and 1982, a survey was conducted to determine the impact of the parasite, Aphelinus perpallidus (Gahan), on populations of the blackmargined aphid, Monellia caryella (Fitch), in far west Texas. Parasitism did have a moderate impact on aphid populations in most of the orchards sampled in El Paso County. In 1981, peak percentage parasitism ranged from 6% in the Fabens orchard to 17% in the El Paso orchard. In 1982 peak percentage parasitism generally increased and ranged from 25% in the El Paso orchard to 30% in the Ysleta and Tornillo orchards. Further information on the phenology of A. perpallidus from each site is presented.
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Newton, Philip J. "Movement and impact of Trichogrammatoidea cryptophlebiae Nagaraja (Hymenoptera: Trichogrammatidae) in citrus orchards after inundative releases against the false codling moth, Cryptophlebia leucotreta (Meyrick) (Lepidoptera: Tortricidae)." Bulletin of Entomological Research 78, no. 1 (March 1988): 85–99. http://dx.doi.org/10.1017/s0007485300016096.
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AbstractInundative releases of the indigenous egg parasitoid Trichogrammatoidea cryptophlebiae Nagaraja were made against Cryptophlebia leucotreta (Meyrick) in two sweet orange orchards in the Transvaal lowveld, South Africa. The rate of parasitism was raised to similar levels in the two release areas, but there was a significant decrease in crop damage in only one of them. Although the larval population was twice as large in a control orchard, the losses there were compensated for by a larger total crop. Three explanations for the different performances of the parasitoids are examined. Movement away from release areas was not apparent. Rates of parasitism at the tops or bottoms of trees or at the four cardinal aspects were not significantly different overall but should have been to compensate for the linear increase in numbers of host eggs with height, and the larger numbers on the warmer northern and eastern sides of trees. Parasitism was higher at the tree tops than at the bottoms in the orchard that lost the least fruit. The stochastic processes governing host-egg distribution on fruit were also important. Pest density was higher in the release areas than the control, and eggs were distributed more contagiously in the orchard with the most crop loss.