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1
Sun, Q., W. S. Meyer, G. R. Koerber, and P. Marschner. "Response of respiration and nutrient availability to drying and rewetting in soil from a semi-arid woodland depends on vegetation patch and a recent wildfire." Biogeosciences 12, no. 16 (August 27, 2015): 5093–101. http://dx.doi.org/10.5194/bg-12-5093-2015.
Повний текст джерелаАнотація:
Abstract. Semi-arid woodlands, which are characterised by patchy vegetation interspersed with bare, open areas, are frequently exposed to wildfire. During summer, long dry periods are occasionally interrupted by rainfall events. It is well known that rewetting of dry soil induces a flush of respiration. However, the magnitude of the flush may differ between vegetation patches and open areas because of different organic matter content, which could be further modulated by wildfire. Soils were collected from under trees, under shrubs or in open areas in unburnt and burnt sandy mallee woodland, where part of the woodland experienced a wildfire which destroyed or damaged most of the aboveground plant parts 4 months before sampling. In an incubation experiment, the soils were exposed to two moisture treatments: constantly moist (CM) and drying and rewetting (DRW). In CM, soils were incubated at 80 % of maximum water holding capacity (WHC) for 19 days; in DRW, soils were dried for 4 days, kept dry for another 5 days, then rewetted to 80 % WHC and maintained at this water content until day 19. Soil respiration decreased during drying and was very low in the dry period; rewetting induced a respiration flush. Compared to soil under shrubs and in open areas, cumulative respiration per gram of soil in CM and DRW was greater under trees, but lower when expressed per gram of total organic carbon (TOC). Organic matter content, available P, and microbial biomass C, but not available N, were greater under trees than in open areas. Wild fire decreased the flush of respiration per gram of TOC in the open areas and under shrubs, and reduced TOC and microbial biomass C (MBC) concentrations only under trees, but had little effect on available N and P concentrations. We conclude that the impact of wildfire and DRW events on nutrient cycling differs among vegetation patches of a native semi-arid woodland which is related to organic matter amount and availability.
2
Sun, Q., W. S. Meyer, G. Koerber, and P. Marschner. "Response of respiration and nutrient availability to drying and rewetting in soil from a semi-arid woodland depends on vegetation patch and a recent wild fire." Biogeosciences Discussions 12, no. 11 (June 12, 2015): 8723–45. http://dx.doi.org/10.5194/bgd-12-8723-2015.
Повний текст джерелаАнотація:
Abstract. Semi-arid woodlands, which are characterised by patchy vegetation interspersed with bare, open areas, are frequently exposed to wild fire. During summer, long dry periods are occasionally interrupted by rainfall events. It is well-known that rewetting of dry soil induces a flush of respiration. However, the magnitude of the flush may differ between vegetation patches and open areas because of different organic matter content which could be further modulated by wild fire. Soils were collected from under trees, under shrubs or in open areas in unburnt and burnt sandy Mallee woodland, where part of the woodland experienced a wild fire which destroyed or damaged most of the aboveground plant parts four months before sampling. In an incubation experiment, the soils were exposed to two moisture treatments: constantly moist (CM) and drying and rewetting (DRW). In CM, soils were incubated at 80% of maximum water holding capacity for 19 days; In DRW, soils were dried for four days, kept dry for another five days, then rewet to 80% WHC and maintained at this water content until day 19. Soil respiration decreased during drying and was very low in the dry period; rewetting induced a respiration flush. Compared to soil under shrubs and in open areas, cumulative respiration per g soil in CM and DRW was greater under trees, but lower when expressed per g TOC. Organic matter content, available P, and microbial biomass C, but not available N were greater under trees than in open areas. Wild fire decreased the flush of respiration per g TOC in the open areas and under shrubs, and reduced TOC and MBC concentrations only under trees, but had little effect on available N and P concentrations. We conclude that of the impact wild fire and DRW events on nutrient cycling differ among vegetation patches of a native semiarid woodland which is related to organic matter amount and availability.
3
West, AW, GP Sparling, TW Speir, and JM Wood. "Comparison of microbial C, N-flush and ATP, and certain enzyme activities of different textured soils subject to gradual drying." Soil Research 26, no. 1 (1988): 217. http://dx.doi.org/10.1071/sr9880217.
Повний текст джерелаАнотація:
A clay loam, a silt loam and a sand soil were gradually dried from field moisture content to air-dryness at 25�C in the laboratory. Microbial C measured by substrate-induced respiration (SIR), fumigation-incubation (FI) and fumigation-extraction (FE), microbial N-flush measured by FI and FE, microbial ATP content, and soil phosphatase and sulfatase activities were monitored throughout a drying period of approx. 60 h achieved over 16 days. All the microbial and enzyme variables declined as the gravimetric soil water content ( W) decreased to air-dryness. In general, the relationship between microbial C or N-flush and W was linear, but was exponential between ATP or phosphatase and W. Soil texture appeared to affect the rates of decline and also the amounts of the microbial and enzyme variables remaining in air-dry soil; e.g., the lowest rate of microbial C decline and the largest amount remaining at air-dryness occurred in the clay loam soil. Sulfatase activity was not significantly affected by soil drying. Agreement between the SIR and FE estimates of microbial C was good (r = 0.92***). These two methods were applicable over a wide range of water contents. Microbial N-flush, estimated by the FE method, also showed a consistent trend and correlated highly with microbial C estimated by SIR or FE. In contrast, microbial C and N-flush estimated by the FI method were not significantly correlated with W or any of the other variables. ATP and phosphatase activity appeared to relate more closely to microbial activity (CO2 respiration/microbial C) than microbial mass. The reliability of the methods to measure the biomass and the influence of soil texture, water and carbon contents on microbial survival are discussed.
4
Shirley, Larissa K., Tyler Field, Allan P. Schinckel, Jay S. Johnson, Robert Stwalley, and Kara R. Stewart. "80 Use of an Electronically-controlled Floor Cooling Pad During Heat Stress on Thermoregulatory and Reproductive Performance in Boars." Journal of Animal Science 99, Supplement_1 (May 1, 2021): 107. http://dx.doi.org/10.1093/jas/skab054.174.
Повний текст джерелаАнотація:
Abstract This study was designed to evaluate the effects of electronically-controlled floor cooling pads on thermoregulatory and reproductive parameters in boars during heat stress (HS). Boars (n = 24) were randomly assigned to crates with non-functional pads (CON) or pads that were flushed in either 8-min intervals or when the pad reached 28.5°C (FLUSH). For 3 d, boars were subjected to cyclical HS (28 to 35°C; >65% relative humidity). Boars were fed 2.4 kg/d and daily feed intake was recorded. Respiration rate (RR), rectal temperature (Rtemp) and skin temperature were recorded every 2 h during HS (via IR camera), testicular temperature was recorded twice daily. Semen was collected d7 and d14 before HS, the day following HS and weekly for 6 weeks and evaluated for volume, sperm concentration, motility, progressive motility, morphological abnormalities, and viability. After 2 h of HS, FLUSH boars had reduced RR (P < 0.001) and RTemp (P < 0.001) when compared to control boars, and this difference was maintained throughout HS. Skin and testicular temperature were reduced in FLUSH vs. CON boars after 6 h of HS (P < 0.05). Semen volume was greater in FLUSH vs CON boars (P = 0.01) resulting in a tendency for an increase in total sperm per ejaculate (P = 0.075). From weeks 2 to 5 post-HS, FLUSH boars had increased motility (P = 0.006) and progressive motility (P = 0.001), with corresponding increases in sperm kinematic motion parameters when compared to CON boars. The number of morphologically normal sperm cells were increased (P = 0.006) in FLUSH vs CON boars due to reduced distal droplets (P = 0.033) and proximal droplets (P < 0.001). Abnormal acrosomes were reduced (P < 0.001) in FLUSH vs CON boars at week 3 post-HS. In summary, electronically controlled cooling pads effectively reduced negative thermoregulatory indicators of HS and minimized or removed the negative impacts of HS on semen quality in boars.
5
Pachpor, N. S., and A. V. Mane. "Effect of plant growth regulator (PGR) and cultural practices on supression of post monsoon vegetative flush in relation to physiological and yield parameters of alphonso mango (Mangifera indica L.)." INTERNATIONAL JOURNAL OF AGRICULTURAL SCIENCES 18, no. 2 (June 15, 2022): 577–88. http://dx.doi.org/10.15740/has/ijas/18.2/577-588.
Повний текст джерелаАнотація:
This experimental work was performed on Alphonso mango treeat Centre of Excellence for Mango, Department of Horticulture, Dr. Balasaheb Sawant Konkan KrishiVidyapeeth, Dapoli, during mango growing season summer-winter 2016 -2017 and 2017-2018. It is observed that the post- monsoon vegetative flush in mango trees affects reproductive phase that ultimately cause huge economic loss and so the study aimed at the effect of plant growth regulator (PGR) and cultural practices on supression of post monsoon vegetative flush in relation to physiological and yield parameters. The experiment laid out in ten treatments viz,. T1_ control,T2_ CCC-1500 ppm,T3_CCC-2500 ppm,T4_foliar spray of diammonium phosphate 3%,T5_PBZ-500 ppm,T6_PBZ-1000 ppm,T7_ PBZ- 2000 ppm,T8_ Soil opening upto the depth of 4-5 inch at tree basin region once in last week of September,T9_ Soil opening upto the depth of 4-5 inch at tree basin region once in last week of October and T10_Soil opening upto the depth of 4-5 inch at tree region twice in last week of September and last week of October. Among physiological parameters considered, the rate of photosynthesis was maintained at significantly highest rate (7.44 μmol CO2 m-2s-1) by treatment T10. The rate of respiration was found to be increased from before bud break stage to bud break stage and then declines towards flower initiation stage. In case of rate of transpiration, treatment T10 maintained significantly highest rate of respiration from before bud break stage to flower initiation stage and recorded highest rate of respiration at bud break stage (-6.03 μmol CO2 m-2s-1). In case of yield, treatment T10 recorded significantly minimum days required for harvesting (102.16 days) from flowering among all treatments. Significantly maximum days required for harvesting (129.83 days) was recorded by T1.The treatment T10 recorded significantly maximum number of fruits per plant (188.50) followed by treatment T3 (184.16), significantly minimum fruits per tree (89.50) was recorded by T1.The fruits per tree (kg) was found to be significantly higher (48.96 kg) in T10.
6
Shirley, Larissa, Morgan Burgett, Tyler Field, Allan P. Schinckel, Kara R. Stewart, Ricardo M. Garcia, Jay S. Johnson, and Robert Stwalley. "PSVIII-19 Evaluation of Cooling Pads on Late Lactating Sows." Journal of Animal Science 98, Supplement_3 (November 2, 2020): 223. http://dx.doi.org/10.1093/jas/skaa054.389.
Повний текст джерелаАнотація:
Abstract An electronically controlled cooling pad has been developed to remove excess heat from sows using water cooled by flowing through underground pipes. This study was designed to evaluate different water flush rates on physiological measures of heat stress on day 16 to 21 of lactation. Twelve sows were randomly assigned to 3 treatments (control (CN), flush 2.0 L over 30 sec every 2.5 minutes (F2.5), or flush every 5 minutes (F5)) in a Latin square design. Feed intake (FI) was recorded daily at 0700 h. Temperatures were gradually increased from 22°C at 0800 h to 32°C by 0930 h. Then 32°C was maintained until 1500 h, when cooling of the room began. After 1800 h, the cooling pads were flushed every 9 minutes. Rectal temperature (RTemp), skin temperature (STemp), and respiration rates (RR) were measured at 0700, 0730, 0900, 1200, 1500, and 1800 h daily, with thermal imaging (IR) being taken at 1200 and 1500 h. The effects of flush rate (amount of water flushed) on STemp were linear (P=0.023), with means of 35.9, 35.0, and 35.9°C for the CN, F2.5, and F5.0 treatments. Pad flush rate effects of RTemp were linear (P< 0.001) and were greater in CN sows compared to F2.5 and F5 (39.3°, 38.8°, and 38.9°C), P< 0.0001). RR was affected by treatment (60 vs 42 and 50 breaths/min, P< 0.005 for CN, F2.5, and F5.0 treatments). Treatment by time interactions were significant for RR (P=0.0003) and RTemp (P=< 0.0001), with the greatest differences at 1200 and 1500 times (RR = 89, 48, & 65; and RTemp 39.9, 39.0, & 39.2°C for CN, F2.5, and F5.0 treatments). Skin temps measured by thermal imaging were not different among treatments (P=0.38) nor DFI (P=0.41). Cooling pad use with a flush rate of 2.0 L/2.5 min reduced body temperature to euthermia without increasing RR most effectively. This has implications toward reducing energy expenditure for thermoregulatory processes, which can increase nutrient availability for lactation during HS.
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van Straaten, O., E. Veldkamp, M. Köhler, and I. Anas. "Drought effects on soil CO<sub>2</sub> efflux in a cacao agroforestry system in Sulawesi, Indonesia." Biogeosciences Discussions 6, no. 6 (December 15, 2009): 11541–76. http://dx.doi.org/10.5194/bgd-6-11541-2009.
Повний текст джерелаАнотація:
Abstract. Climate change induced droughts pose a serious threat to ecosystems across the tropics and sub-tropics, particularly to those areas not adapted to natural dry periods. In order to study the vulnerability of cacao (Theobroma cacao) – Gliricidia sepium agroforestry plantations to droughts a large scale throughfall displacement roof was built in Central Sulawesi, Indonesia. In this 19-month replicated experiment, we measured soil surface CO2 efflux (soil respiration) in three simulated drought plots compared with three adjacent control plots. Soil respiration rates peaked at intermediate soil moisture and decreased under increasingly dry conditions (drought induced), but also decreased when soils became water saturated, as evidenced in control plots. The simulated drought plots exhibited a slight decrease in soil respiration compared to the control plots (average 13% decrease). The strength of the drought effect was spatially variable – while some measurement chamber sites reacted strongly ("responsive") to the decrease in soil water content (up to R2=0.70) (n=11), others did not react at all ("non-responsive") (n=7). The degree of soil CO2 respiration drought response was highest around cacao tree stems and decreased with distance from the stem (R2=0.22). A significant correlation was measured between "responsive" soil respiration chamber sites and sap flux density ratios of cacao (R=0.61) and Gliricidia (R=0.65). Leaf litter CO2 respiration decreased as conditions became drier. During dry periods the litter layer contributed approximately 3–4% of the total CO2 efflux and up to 40% during wet periods. A CO2 flush was recorded during the rewetting phase that lasted for approximately two weeks, during which time accumulated labile carbon stocks mineralized. The net effect on soil CO2 emissions over the duration of the experiment was neutral, control plots respired 11.1±0.5 Mg C ha−1 yr−1, while roof plots respired 10.5±0.5 Mg C ha−1 yr−1.
8
Autio, Wesley R., William J. Bramlage, and Sarah A. Weis. "Predicting Poststorage Disorders of ‘Cox's Orange Pippin’ and ‘Bramley's Seedling’ Apples by Regression Equations." Journal of the American Society for Horticultural Science 111, no. 5 (September 1986): 738–42. http://dx.doi.org/10.21273/jashs.111.5.738.
Повний текст джерелаАнотація:
Abstract Equations were developed that could predict the incidence of senescent breakdown, bitter pit, and decay in ‘Cox's Orange Pippin’ apples and senescent breakdown and bitter pit in ‘Bramley's Seedling’ apples. The parameters used to predict the incidences of disorders included fruit Ca, P, and K concentrations; fruit weight; respiration rate; and fruit maturity. Each disorder and each cultivar had a unique prediction equation. Such equations must be established individually for a disorder, cultivar, and, probably, growing region. Given an appropriate data base, this method seems to have broad applicability as a predictive tool for these disorders. However, core flush and low temperature breakdown could not be predicted using the parameters measured in this study.
9
Chowdhury, Nasrin, Nan Yan, Md Nazrul Islam, and Petra Marschner. "The extent of drying influences the flush of respiration after rewetting in non-saline and saline soils." Soil Biology and Biochemistry 43, no. 11 (November 2011): 2265–72. http://dx.doi.org/10.1016/j.soilbio.2011.07.013.
Повний текст джерела
10
Marchi, Susanna, Luca Sebastiani, Riccardo Gucci, and Roberto Tognetti. "Changes in Sink-source Relationships during Shoot Development in Olive." Journal of the American Society for Horticultural Science 130, no. 4 (July 2005): 631–37. http://dx.doi.org/10.21273/jashs.130.4.631.
Повний текст джерелаАнотація:
Net photosynthesis, dark respiration, chlorophyll and carbohydrate content, and leaf and shoot growth in plants of evergreen olive (Olea europaea L.) grown under controlled conditions were measured to assess changes in carbon balance during leaf development of the 6th, 12th, and 16th node (from the base, first flush) through expansion to maturity. Shoot and leaves expanded in a sigmoid pattern with differences among nodes. Photosynthesis varied with leaf development; young leaves had low CO2 assimilation rates that were reflected in their chlorophyll concentration. Net daily CO2 assimilation was negative in young expanding leaves. The sink-source transition, defined to be the time when the increase in daily carbohydrate exchange rate exceeds the daily increase in leaf carbohydrate content, occurred before full leaf expansion, between 10% and 30% expansion depending on the node.
11
West, AW, GP Sparling, TW Speir, and JM Wood. "Dynamics of microbial-C, N-flush and ATP, and enzyme activities of gradually dried soils from a climosequence." Soil Research 26, no. 3 (1988): 519. http://dx.doi.org/10.1071/sr9880519.
Повний текст джерелаАнотація:
Three silt loam soils from a climosequence (1000-2700 mm annual rainfall) were gradually dried from field moisture content to air-dryness at 25�C in the laboratory. Microbial C measured by substrate-induced respiration (SIR), fumigation-incubation (FI) or fumigation-extraction (FE), microbial N-flush measured by FI and FE, microbial ATP content and soil phosphatase and sulfatase activities were monitored throughout the drying period (approx. 60 h). All indices declined as the gravimetric soil water content (W) decreased until reaching air-dryness. Significant declines in the biomass sometimes occurred only following a large decrease in W, dependent on the soil. In general, when microbial C and N-flush declined, the rates of decline were linearly correlated with W. However, ATP and soil phosphatase were exponentially related to W. When expressed as a ratio of the total change in microbial indices against the total change in W for the whole drying period, the ratios were consistent between the soils. Agreement between the SIR and FE estimates of microbial C, whilst significant (r = 0 58***), was poor, especially for the low rainfall soil, although the FE C- and N-flushes correlated well (r = 0-76***). In contrast, the FI C- and N-flushes correlated very poorly (r = 0.30**) and were not significantly correlated with W or the other indices. ATP and soil phosphatase activity were strongly correlated (r = 0.89***). The reliability of the methods and the influence of soil moisture regimes on microbial survival are discussed.
12
Thierron, Viviane, and H. Laudelout. "Contribution of root respiration to total CO2 efflux from the soil of a deciduous forest." Canadian Journal of Forest Research 26, no. 7 (July 1, 1996): 1142–48. http://dx.doi.org/10.1139/x26-127.
Повний текст джерелаАнотація:
The measurement of CO2 efflux from forest soils has become of great importance in evaluating the role of forests as sequestering agents of atmospheric CO2. In this regard, it is important to know the part of total efflux that originates from root respiration. We have tried to evaluate it by measuring efflux in the field with a portable infrared gas analyzer, while at the same time, the 0–10 cm soil layer was sampled and incubated in the laboratory during 30–40 days. Comparison of field and laboratory measurements was made by conversion to a common temperature (10 °C) using the Arrhenius equation for both processes. Results indicated an Arrhenius apparent activation energy of 25 kcal (1 kcal = 4.1855 kJ) in the field and 15 kcal in the laboratory. Comparison of the results was also made possible by modelling the cumulative CO2 efflux in the laboratory so that we eliminated the initial flush of mineralization, the value of which was temperature dependent. The grand average of CO2 efflux from the forest soil calculated for the whole year from the temperature of the soil and the Arrhenius equation was 70 Mg•ha−1•year−1, of which 90% originated from the roots.
13
Murphy, D. V., G. P. Sparling, I. R. P. Fillery, A. M. McNeill, and P. Braunberger. "Mineralisation of soil organic nitrogen and microbial respiration after simulated summer rainfall events in an agricultural soil." Soil Research 36, no. 2 (1998): 231. http://dx.doi.org/10.1071/s97043.
Повний текст джерелаАнотація:
Simulated rainfall events were applied during the summer fallow period to a Western Australian agricultural soil, a loamy sand, under continuous wheat and after the second pasture phase of a 2 pasture : 1 wheat (2P : 1W) rotation. The aims of this study were to determine the change in microbial activity, amount of net and gross nitrogen (N) mineralised, and inorganic N produced after dry soil was re-wet during summer rainfall. Three irrigation treatments were applied: (i) control soils received no water, (ii) the single wet treatment received 45 mm of water on day 0 and was allowed to dry, and (iii) the multiple wet treatment received 45 mm of water on day 0 plus further applications of 5 mm on days 3 and 8. The CO2 production and N mineralisation were measured in the surface 10 cm of soil for a period of 14 days after initial irrigation. Net N mineralisation was measured from in situ incubation of soil cores and gross N mineralisation by 15N isotopic dilution. The CO2 production was measured by infrared gas analysis of air samples taken from a closed headspace above the soil. A large flush in CO2 production and gross N mineralisation occurred immediately after rewetting the dry soil. This response was short-lived and rates of CO2 production and gross N mineralisation declined rapidly after 2 days. After irrigation on day 0, CO2 production was twice as large and gross N mineralisation was slightly larger in the 2P : 1W soil than continuous wheat. Gross N mineralisation and CO2 production were not significantly different in the multiple and single wet treatments after the re-wet on day 3, but an additional flush in activity occurred in the multiple wet treatment after the re-wet on day 8. The patterns of gross N mineralisation and CO2 production corresponded to changes in the soil water content, especially in the surface 2·5 cm of soil. Net and gross N mineralised and gross N immobilised over the 14-day period after the initial re-wet were greater in the multiple wet compared with the single wet treatments under both wheat and 2P : 1W. However, gross N mineralisation was approximately 4-fold greater than net N mineralisation under wheat and 15-fold greater under 2P : 1W. The majority of gross N mineralised after simulated summer rainfall was immobilised which resulted in an increase in inorganic N within the soil profile (0-50 cm) during opening winter rains.
14
Cleaver, Kristen N., Larissa K. Shirley, Tyler Field, Brooklyn A. Hill, Kouassi R. Kpodo, Jay S. Johnson, Robert Stwalley, and Allan P. Schinckel. "PSI-11 Evaluation of Electronically Controlled Cooling Pad Flush Rates on Heat Stressed Gilts." Journal of Animal Science 99, Supplement_1 (May 1, 2021): 133. http://dx.doi.org/10.1093/jas/skab054.224.
Повний текст джерелаАнотація:
Abstract This study was designed to evaluate the effects of electronically controlled cooling pads on measures of physiological responses in HS gilts. The study utilized 12 gilts randomly assigned into one of three treatment groups [Control(CN), flush 2.0 L cool water over 30 s every 4 min(F4), or flush 2.0 L over 30 s every 8 min(F8)] in a Latin Square design and replicated 12 times(2 repetitions/d over 6 d). Gilts were housed in farrowing crates and fed 1.2 kg at 0700 and 1300 h daily. On d 1 to 3(6 repetitions) the room was gradually heated from 18ºC to 32ºC, while on d 4 to 6 the room was gradually heated from 18ºC to 35ºC starting at 0730 or 1330 h. Once the temperature was achieved, cooling pads were turned on and the temperature was maintained for 2.5 h. Two baseline measurements were taken of respiration rates(RR), skin temperature through thermal imaging(IRTemp), and vaginal temperature(VTemp) before room heating began and then recorded every 20 minutes after pads were turned on. Measurements at the end of HS(PostH) and the change in values during the HS period(DIFF) were evaluated using PROC mixed of SAS. Gilts in F4 and F8 had lower RR than CN for PostH for both 32ºC and 35ºC (P< .05). DIFF in RR was less in F4 and F8 than in CN[(32ºC, P=.097) and (35ºC, P=.005)]. There was a tendency for DIFF in Vtemp at 32ºC between treatments (P=.064) but had no effect by treatment for PostH (P=.534). There was no effect in PostH and DIFF for IRTemp between treatments for 32ºC and 35ºC. PostH and DIFF for VTemp were significant at 35ºC (P=.009 and P=.001). PostH for RR was different at 35 ºC and 32 ºC (P=.0074; P=.0472) with F4 and F8 lesser and CN. In conclusion, cooling pads, regardless of flush rate, had positive impacts on physiological indicators of HS.
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Collins, SL, J. Kull, C. Benham, P. Krawczel, KD Donohue, and M. Caldwell. "Comparison of penetrating and non-penetrating captive bolt in an alternative occipital approach in calves." Animal Welfare 29, no. 1 (January 1, 2020): 59–67. http://dx.doi.org/10.7120/09627286.29.1.059.
Повний текст джерелаАнотація:
The objective of this study was to describe the effect of penetrating or non-penetrating captive bolt using an occipital approach in 4–5 month old, Holstein steers weighing between 100–200 kg. Twelve calves were divided into two treatment groups; penetrating captive bolt (PCB; n = 6) and non-penetrating captive bolt (NPCB; n = 6). This sample size was chosen out of convenience and in conjunction with a separate study. Each calf was sedated with xylazine hydrochloride, then a captive-bolt device, outfitted with a standard penetrating bolt or a non-penetrating bolt, was placed flush on the dorsal midline of the cranium at the external occipital protuberance and aimed downward as though to intersect the intermandibular area. Following impact, indicators for loss of consciousness, such as respiration, righting response, corneal reflex, movement and vocalisation were recorded and characterised along with electrocardiogram and electroencephalogram recordings. After a 5-min observation period, all calves were administered potassium chloride. All calves experienced immediate and sustained loss of consciousness. The mean (± SEM) time to cessation of respiration was 60 (± 53.67) and 0 (± 0.0) s for PCB and NPCB, respectively. The mean time to cessation of convulsions was 310.4 (± 79.74) and 180.0 (± 60.24) s, respectively, and the mean number of convulsions was 2.75 (± 1.03) and 2.0 (± 0.837) for PCB and NPCB, respectively. Isoelectric EEG patterns were observed in 3/5 PCB and 3/4 NPCB with mean time to onset of isoelectric pattern in 69.0(± 52.24) and 113.5 (± 56.87) s. Both treatments induced a successful stun, which suggests these techniques are appropriate for humane euthanasia in calves of this age.
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Schirra, M., M. Agabbio, S. D'Aquino, and T. G. McCollum. "Postharvest Heat Conditioning Effects on Early Ripening `Gialla' Cactus Pear Fruit." HortScience 32, no. 4 (July 1997): 702–4. http://dx.doi.org/10.21273/hortsci.32.4.702.
Повний текст джерелаАнотація:
The influence of postharvest heat conditioning at 38 °C for 24, 48, or 72 hours on ripe `Gialla' cactus pear [Opuntia ficus-indica (L.) Miller] fruit produced by the spring flush was investigated during 21 days of storage at 6 °C and 90%-95% relative humidity (RH) followed by 7 days at 20 °C and 70%-75% RH (simulated marketing). Conditioning for 24 to 72 h reduced by 50% the severity of chilling injury (CI) on cactus pears following exposure to cold storage. Treatment for 24 to 72 h was also effective in reducing decay, with conditioning for 24 h being the most effective. Overall visual quality was better in heat-conditioned compared with control fruit. Mass loss was significantly reduced by all heat conditioning treatments. Respiration rate was not affected by heat treatment. Ethylene evolution was lower in fruit heat-conditioned for 48 or 72 h than for 0 h. Conditioning for 72 h resulted in the highest fruit ethanol levels. The influence of conditioning on juice pH, titratable acidity, soluble solids concentration and ascorbic acid was negligible. Prestorage heat treatment provides some measure of CI and decay control without detrimental effects to visual quality of early ripening cactus pear fruit and may offer an alternative to fungicide treatments.
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Samuelson, Lisa J., Thomas L. Eberhardt, John R. Butnor, Tom A. Stokes, and Kurt H. Johnsen. "Maximum growth potential in loblolly pine: results from a 47-year-old spacing study in Hawaii." Canadian Journal of Forest Research 40, no. 10 (October 2010): 1914–29. http://dx.doi.org/10.1139/x10-133.
Повний текст джерелаАнотація:
Growth, allocation to woody root biomass, wood properties, leaf physiology, and shoot morphology were examined in a 47-year-old loblolly pine ( Pinus taeda L.) density trial located in Maui, Hawaii, to determine if stands continued to carry the high density, basal area, and volume reported at younger ages and to identify potential factors controlling expression of maximum growth potential. Basal area and volume were similar among spacings (square: 1.8, 2.4, 3.0, and 3.7 m) and averaged 93 m2·ha–1 and 1076 m3·ha–1, respectively, and were double the maxima reported for loblolly pine in its native range. Spacing had a significant influence on density, quadratic mean diameter, and height. Ring-specific gravity and percent latewood were similar among spacing treatments but values were high compared to mainland stands. Leaf light-saturated net photosynthesis, dark respiration, stomatal conductance, and quantum yield were comparable with values reported for loblolly pine in its native range. Foliar calcium concentrations, specific leaf area, and flush number were high in the Hawaii study. Higher carrying capacity in Hawaii may be related to a more favorable climate conducive to year-round leaf carbon gain, high nutrient availability, increased flushing, and less allocation to belowground mass.
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Marchi, Susanna, Luca Sebastiani, Riccardo Gucci, and Roberto Tognetti. "Sink-source Transition in Peach Leaves during Shoot Development." Journal of the American Society for Horticultural Science 130, no. 6 (November 2005): 928–35. http://dx.doi.org/10.21273/jashs.130.6.928.
Повний текст джерелаАнотація:
Net photosynthesis, dark respiration, chlorophyll and carbohydrate content, and leaf and shoot growth of deciduous peach [Prunus persica (L.) Batsch] saplings, grown in greenhouse conditions, were measured to assess changes in carbon balance during leaf development. The 6th, 12th, and 16th leaf node were measured from the first flush at the base through expansion to maturity (the first node being the oldest). Shoot and leaves expanded following a sigmoid pattern in all nodes. The shape of the logistic curve did not vary between the 6th and the 16th leaf node, while the 12th leaf node showed a steeper response, suggesting that the latter reached 50% expansion relatively earlier. Photosynthesis varied with leaf development as young leaves had low CO2 assimilation rates that were reflected in their chlorophyll concentration. Net daily CO2 assimilation was negative in young expanding leaves. The sink-source transition, defined to be the time when the increase in daily carbohydrate exchange rate exceeded the daily increase in leaf carbohydrate content, occurred before full leaf expansion. The transition from import to export was attained 11-12 days after budbreak (corresponding to 41% to 45% of full leaf expansion) for the 6th leaf, about 7-9 days after (38% to 52% of full expansion) for the 12th leaf and after 9-10 days (32% to 38% of full expansion) for the 16th leaf. Below 30% to 50% of full expansion leaves might not respond to assimilate requirements from sinks, being sinks themselves.
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Moustapha, Moussa, Loris Deirmendjian, David Sebag, Jean-Jacques Braun, Stéphane Audry, Henriette Ateba Bessa, Thierry Adatte, et al. "Partitioning carbon sources between wetland and well-drained ecosystems to a tropical first-order stream – implications for carbon cycling at the watershed scale (Nyong, Cameroon)." Biogeosciences 19, no. 1 (January 7, 2022): 137–63. http://dx.doi.org/10.5194/bg-19-137-2022.
Повний текст джерелаАнотація:
Abstract. Tropical rivers emit large amounts of carbon dioxide (CO2) to the atmosphere, in particular due to large wetland-to-river carbon (C) inputs. Yet, tropical African rivers remain largely understudied, and little is known about the partitioning of C sources between wetland and well-drained ecosystems to rivers. In a first-order sub-catchment (0.6 km2) of the Nyong watershed (Cameroon 27 800 km2), we fortnightly measured C in all forms and ancillary parameters in groundwater in a well-drained forest (hereafter referred to as non-flooded forest groundwater) and in the stream. In the first-order catchment, the simple land use shared between wetland and well-drained forest, together with drainage data, allowed the partitioning of C sources between wetland and well-drained ecosystems to the stream. Also, we fortnightly measured dissolved and particulate C downstream of the first-order stream to the main stem of order 6, and we supplemented C measurements with measures of heterotrophic respiration in stream orders 1 and 5. In the first-order stream, dissolved organic and inorganic C and particulate organic C (POC) concentrations increased during rainy seasons when the hydrological connectivity with the riparian wetland increased, whereas the concentrations of the same parameters decreased during dry seasons when the wetland was shrinking. In larger streams (order > 1), the same seasonality was observed, showing that wetlands in headwaters were significant sources of organic and inorganic C for downstream rivers, even though higher POC concentration evidenced an additional source of POC in larger streams during rainy seasons that was most likely POC originating from floating macrophytes. During rainy seasons, the seasonal flush of organic matter from the wetland in the first-order catchment and from the macrophytes in higher-order rivers significantly affected downstream metabolism, as evidenced by higher respiration rates in stream order 5 (756 ± 333 gC-CO2 m−2 yr−1) compared to stream 1 (286 ± 228 gC-CO2 m−2 yr−1). In the first-order catchment, the sum of the C hydrologically exported from non-flooded forest groundwater (6.2 ± 3.0 MgC yr−1) and wetland (4.0 ± 1.5 MgC yr−1) to the stream represented 3 %–5 % of the local catchment net C sink. In the first-order catchment, non-flooded forest groundwater exported 1.6 times more C than wetland; however, when weighed by surface area, C inputs from non-flooded forest groundwater and wetland to the stream contributed to 27 % (13.0 ± 6.2 MgC yr−1) and 73 % (33.0 ± 12.4 MgC yr−1) of the total hydrological C inputs, respectively. At the Nyong watershed scale, the yearly integrated CO2 degassing from the entire river network was 652 ± 161 GgC-CO2 yr−1 (23.4 ± 5.8 MgC CO2 km−2 yr−1 when weighed by the Nyong watershed surface area), whereas average heterotrophic respiration in the river and CO2 degassing rates was 521 ± 403 and 5085 ± 2544 gC-CO2 m−2 yr−1, which implied that only ∼ 10 % of the CO2 degassing at the water–air interface was supported by heterotrophic respiration in the river. In addition, the total fluvial C export to the ocean of 191 ± 108 GgC yr−1 (10.3 ± 5.8 MgC km−2 yr−1 when weighed by the Nyong watershed surface area) plus the yearly integrated CO2 degassing from the entire river network represented ∼ 11 % of the net C sink estimated for the whole Nyong watershed. In tropical watersheds, we show that wetlands largely influence riverine C variations and budget. Thus, ignoring the river–wetland connectivity might lead to the misrepresentation of C dynamics in tropical watersheds.
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Adams, M. B., N. T. Edwards, G. E. Taylor Jr., and B. L. Skaggs. "Whole-plant 14C-photosynthate allocation in Pinustaeda: seasonal patterns at ambient and elevated ozone levels." Canadian Journal of Forest Research 20, no. 2 (February 1, 1990): 152–58. http://dx.doi.org/10.1139/x90-021.
Повний текст джерелаАнотація:
The seasonal patterns of carbon gain and allocation were examined in Pinustaeda L. seedlings grown under field conditions. To investigate how ozone stress may influence whole-plant carbon budgets over the growing season, the seedlings were grown in either ambient air or air enriched with ozone at twice-ambient levels. On five sampling dates during the 1987 growing season, seedlings were labeled with 14CO2, and whole-plant carbon budgets were constructed. Rate of assimilation of CO2 varied by a factor of 2 during the growing season, with a late spring maximum during the first growth flush. Respiratory losses were highest in the spring and then declined sharply during the summer when photosynthate allocation to the foliage increased rapidly. A second major shift in the carbon budget occurred in the autumn when allocation to the fine roots increased at the expense of the foliage. The proportion of photosynthate allocated to coarse roots and stems varied only slightly over the growing season. Allocation to any plant component was highest when growth of that component was at a maximum. No statistically significant effects of elevated ozone on either carbon gain or photosynthate allocation were detected at any specific time during the growing season. However, seedlings grown at twice-ambient ozone levels consistently exhibited the following trends: (i) lower rates of CO2 assimilation, (ii) greater allocation of photosynthate to respiration, and (iii) corresponding reduction in photosynthate allocation to fine roots. An individual-fascicle 14C-labeling technique was found to reflect the seasonal patterns of carbon import and export by foliage and thus may serve as an acceptable surrogate for whole-tree tagging. The pronounced seasonality of the carbon budgets in P. taeda in conjunction with a pattern of ozone effects on carbon assimilation and photosynthate allocation suggests that whole-plant carbon budgets are sensitive and biologically meaningful indicators of seedlings' responses to anthropogenic changes in atmospheric chemistry.
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Whitmore, Flannery J., Allan P. Schinckel, Robert Stwalley, Tyler Field, Morgan Burgett, Ricardo M. Garcia, and Jay S. Johnson. "56 Impact of Electronically-Controlled Cooling Pads on Physiological Signs of Heat Stress in Early Lactation Sows." Journal of Animal Science 98, Supplement_3 (November 2, 2020): 152–53. http://dx.doi.org/10.1093/jas/skaa054.269.
Повний текст джерелаАнотація:
Abstract The study objective was to evaluate the impact of electronically controlled cooling pads on physiological measurements of heat stress during early lactation. Twelve sows (d 3 to 11 of lactation) were provided with a specially designed cooling pad. Sows randomly received no cooling (CONTROL, n=6) or pads set to flush 2L cool water every 30s when aluminum plate reached 29.5°C (TREAT, n=6). Respiration rates (RR), rectal temperatures (RT) and skin temperatures (ST, 15 cm posterior to the ear) were recorded daily (0700 and 1500 h) for seven days of early lactation. Feed intake (DFI) was measured daily at 0700 h. RR, RT, and ST were fitted to a model that included the effects of day, time, parity, cooling pad treatment, and interactions. DFI was fitted to the same model, excluding time of day. For RR: treatment, day, time, treatment by day, treatment by time, and day by time interactions were significant (P< 0.0004, CONTROL=49, TREAT= 30). Pad treatment had greater impact on RR during the first two days of the trial when the temperature was greater (32°C maximum CONTROL mean=66 vs. TREAT mean=30) than the following five days: 42, and 30 respectively). There was greater treatment impact on RR at 1500 versus 0700 h (0700 h: CONTROL= 35, TREAT= 25; 1500 h: CONTROL= 61, TREAT= 36). For RT: treatment, day, time, parity and interaction of day by time were significant (P< 0.01, CONTROL= 37, treat= 35.). For ST: treatment, day, time, parity and the interactions of time by parity, treatment by time, and day by time were significant (P< 0.0006, mean CONTROL=36.5, TREAT= 35.1). For DFI: day and the interaction of day by treatment were significant. The difference in feed intake between treatments increased as day increased. The use of electronically controlled cooling pads reduced measures of heat stress in early lactating sows.
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Gong, Guohua, Xiaoyun Liu, Huiliang Zhang, Shey-Shing Sheu, and Wang Wang. "Mitochondrial flash as a novel biomarker of mitochondrial respiration in the heart." American Journal of Physiology-Heart and Circulatory Physiology 309, no. 7 (October 2015): H1166—H1177. http://dx.doi.org/10.1152/ajpheart.00462.2015.
Повний текст джерелаАнотація:
Mitochondrial respiration through electron transport chain (ETC) activity generates ATP and reactive oxygen species in eukaryotic cells. The modulation of mitochondrial respiration in vivo or under physiological conditions remains elusive largely due to the lack of appropriate approach to monitor ETC activity in a real-time manner. Here, we show that ETC-coupled mitochondrial flash is a novel biomarker for monitoring mitochondrial respiration under pathophysiological conditions in cultured adult cardiac myocyte and perfused beating heart. Through real-time confocal imaging, we follow the frequency of a transient bursting fluorescent signal, named mitochondrial flash, from individual mitochondria within intact cells expressing a mitochondrial matrix-targeted probe, mt-cpYFP (mitochondrial-circularly permuted yellow fluorescent protein). This mt-cpYFP recorded mitochondrial flash has been shown to be composed of a major superoxide signal with a minor alkalization signal within the mitochondrial matrix. Through manipulating physiological substrates for mitochondrial respiration, we find a close coupling between flash frequency and the ETC electron flow, as measured by oxygen consumption rate in cardiac myocyte. Stimulating electron flow under physiological conditions increases flash frequency. On the other hand, partially block or slowdown electron flow by inhibiting the F0F1 ATPase, which represents a pathological condition, transiently increases then decreases flash frequency. Limiting electron entrance at complex I by knocking out Ndufs4, an assembling subunit of complex I, suppresses mitochondrial flash activity. These results suggest that mitochondrial electron flow can be monitored by real-time imaging of mitochondrial flash. The mitochondrial flash frequency could be used as a novel biomarker for mitochondrial respiration under physiological and pathological conditions.
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Li, Ling, Hai Xue Liu, Yong Bo Peng, Shi Li, and Tie Ling Liu. "Effects of Exogenous Ethylene on AC and Rin Tomato Fruit." Advanced Materials Research 1033-1034 (October 2014): 677–80. http://dx.doi.org/10.4028/www.scientific.net/amr.1033-1034.677.
Повний текст джерелаАнотація:
The flesh firmness of AC andrinmutant tomato fruits picked freshly were the largest. Respiration rate and ethylene production were very low at this time. With ethylene production increase, fruit firmness began to decline. 100μL/L ethephon significantly increased AC tomato fruit ethylene release, respiration rate, ACS activity and ACO activity, and decreased flesh firmness. However, there were no significant differences inrinmutant between control and ethephon treatment. It was shown RIN transcription factor regulated ethylene biosynthesis by ACC synthase and ACC oxidase.
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Miccolis, Vito, and Mikal E. Saltveit. "Morphological and Physiological Changes during Fruit Growth and Maturation of Seven Melon Cultivars." Journal of the American Society for Horticultural Science 116, no. 6 (November 1991): 1025–29. http://dx.doi.org/10.21273/jashs.116.6.1025.
Повний текст джерелаАнотація:
External color, length, diameter, fresh weight, C02 production, internal C2HA concentration, flesh firmness, soluble solids concentration (SSC), flesh color, and seed cavity diameter were measured during fruit growth and maturation of seven melon cultivars (Cucumis melo L., Inodorus Group, Naud. cv. `Amarelo', `Golden Beauty Casaba', `Honey Dew', `Honey Loupe', `Juan Canary', `Paceco', and `Santa Claus Casaba') of known age. There was no increase in C02 production either during ripening (e.g., loss of firmness and increased SSC) or with increasing C2H4 levels in fruit from any of the seven cultivars. There was a significant decline in respiration only at the second sampling date, which ranged from 14 to 18 days after anthesis. Respiration measured 1 week later was substantially higher and was followed by a general decline. This post 14- to 18-day rise in respiration was not a climacteric since it occurred well in advance of other ripening characteristics, e.g., loss of firmness, increase in SSC, or rise in internal C2H4. The increase in internal C2H4. coincided with or followed attainment of full fruit size, while flesh softening and the rapid rise in SSC preceded the rise in internal C2H4, concentration. Respiration declined from 67 to 18 ml CO2/kg per hour by day 43 in all cultivars, except `Honey Dew' and `Honey Loupe'. Respiration in `Honey Loupe' remained above 23 ml CO2/kg per hour and showed a rise to 32 ml/kg per hour on day 53. Respiration in `Honey Dew' did not fall below 18 ml CO2/kg per hour until day 53. As with internal C2H4 levels, there was no correlation between changes in and any marked change in the other signs of ripening that were measured.
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Nanos, George D., Elizabeth Agtsidou, and Evangelos M. Sfakiotakis. "Temperature and Propylene Effects on Ripening of Green and Black 'Conservolea' Olives." HortScience 37, no. 7 (December 2002): 1079–81. http://dx.doi.org/10.21273/hortsci.37.7.1079.
Повний текст джерелаАнотація:
Ripening of detached mature-green and black-ripe olives (Olea europaea L., cv. Conservolea) was studied during storage at 0, 5, 10, or 20 °C in air or air plus 100-200 μL·L-1 propylene. Green olive skin h° remained unchanged after 24 days at 0 or 5 °C in air or air + propylene, while olives partially lost their green color at 10 °C and developed purple color at 20 °C together with a substantial flesh softening. Propylene partially delayed flesh softening only at 10 °C. Respiration of green and black olives increased with storage temperature. Black olives had higher respiration rate than green olives. Propylene had no substantial effect on green or black olive respiration rate, except for an increase in respiration and ripening rates of green olives kept at 20 °C. Ethylene production rate of air- or air + propylene-treated green olives was almost undetectable. Black olives had higher ethylene production rate than green olives and this rate significantly increased with storage temperature. Addition of propylene had only minor effect on ethylene production of black olives. No climacteric respiratory rise or autocatalytic ethylene production was observed in green and black olives.
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Andersson, T., R. Nyman, A. Ericsson, and A. Hemmingsson. "Field-Echo Pulse Sequences Used under Suspended Respiration for Detection of Liver Metastases." Acta Radiologica 30, no. 3 (May 1989): 285–89. http://dx.doi.org/10.1177/028418518903000313.
Повний текст джерелаАнотація:
To obtain a fast MRI sequence for detection of liver metastases under suspended respiration, two healthy volunteers were examined with the field echo sequence FLASH, using a large number of repetition times, echo times, flip angles and matrix sizes. The spleen was used to simulate liver metastases and contrast-to-noise ratios between liver and spleen were calculated and the sequence with the highest ratio was considered optimal. The different FLASH sequences were also compared with spin echo sequences using short repetition and echo times. A FLASH sequence with a repetition time of 140 ms, an echo time of 14 ms, a flip angle of 80 to 100 degrees and a matrix size of 128×256 was considered the most suitable for detecting liver metastases. This sequence, together with other FLASH and spin echo sequences, were used for examination of five patients with liver metastases from endocrine gastrointestinal tumours.
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Crisosto, Carlos H., David Garner, Jim Doyle, and Kevin R. Day. "Relationship between Fruit Respiration, Bruising Susceptibility, and Temperature in Sweet Cherries." HortScience 28, no. 2 (February 1993): 132–35. http://dx.doi.org/10.21273/hortsci.28.2.132.
Повний текст джерелаАнотація:
Respiration rate and bruising incidence were assessed in new cherry (Prunus avium L.) cultivars adapted to high temperatures. `Bing', `Brooks', `Tulare', and `King' respiration rates were evaluated at 0,5,10, and 20C, and bruising susceptibilities at 0, 10, 20, and 30C. `Bing' was the least susceptible to bruising and had the lowest respiration rate at all temperatures. Respiration rate increased with temperature in all cultivars. Impact bruising damage was greatest in all cultivars when fruit flesh was below 10C. Vibration damage was not influenced by fruit temperature. Our results suggest that the cherry cultivars assessed should be handled at temperatures between 10 and 20C during packing to minimize bruising damage. Due to increased respiration rates at higher temperatures, however, fruit should be cooled to 0C within 4 to 6 hours after harvest.
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Cervenak, Sarah Jane. "“Black Night Is Falling”: The “Airy Poetics” of Some Performance." TDR/The Drama Review 62, no. 1 (March 2018): 166–69. http://dx.doi.org/10.1162/dram_a_00727.
Повний текст джерелаАнотація:
Respiration is a choral practice; the interplay between oxygen, hydrogen, and carbon dioxide complexly threads the reproductive fates of oceans, trees, flesh, and cells together. We might say breathing is reproduction’s ur-text.
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De Martin, Mariuccia Schlichting, Cristiano André Steffens, Diego Fernando Pavarin, Marília Farias Rodrigues, Cassandro Vidal Talamine do Amarante, and Auri Brackmann. "Quality maintenance of ‘Laetitia’ plum by application of 1- methylcyclopropene, ethanol vapor and heat treatment." Comunicata Scientiae 9, no. 3 (November 4, 2018): 312–21. http://dx.doi.org/10.14295/cs.v9i3.2767.
Повний текст джерелаАнотація:
The aim of this study was to evaluate the effect of 1-methylcyclopropene (1-MCP), ethanol and heat treatment on ripening behavior and internal browning occurrence of ‘Laetitia’ plum stored under regular air. The treatments were: control, 1-MCP (1,0 µL L-1), ethanol (500 and 1500 µL L-1) and heat treatment (37 and 40 °C) for 24 h. Fruit were stored under regular air for 25 or 35 d at 0.5±0,1 °C and 96±1% relative humidity (RH), and assessed for respiration rate, ethylene production, skin color, flesh firmness, titratable acidity, soluble solids content, incidence of decay and incidence and severity of internal flesh browning. In both storage periods, immediately at removal from cold room, fruit from all the treatments showed lower respiration rate and ethylene production than control fruit. Ethanol vapor at 1500 µL L-1, 1-MCP at 1,0 µL L-1 and heat treatment at 40 °C allowed a less reddish skin after 35 d of storage, as well as higher flesh firmness and lower intensity of internal flesh browning than control fruit, in both evaluated storage periods. In either 25 or 35 d of storage period, heat treatment at 40 °C increased the occurrence of decay. All the treatments provided lower incidence of internal flesh browning than control fruit in both evaluations. The postharvest application of ethanol at 1500 µL L-1, 1-MCP at 1,0 µL L-1 and heat treatment at 40 °C for 24 h delay the ripening process and reduce the incidence of internal flesh browning of ‘Laetitia’ plum.
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Jung, Seok-Kyu, and Hyun-Sug Choi. "Browning of Early and Late-Harvested ‘Empire’ Apples Affected by Cold Storage and 1-MCP." Agronomy 10, no. 7 (July 21, 2020): 1050. http://dx.doi.org/10.3390/agronomy10071050.
Повний текст джерелаАнотація:
The effects of harvest time, 1-methylcyclopropene (1-MCP) and air storage time on the susceptibility of flesh browning in ‘Empire’ apples were studied during a seven-day shelf life period after air storage at 0.5 °C for seven months. Early- or late-harvested ‘Empire’ apples without 1-MCP increased production of ethylene, respiration rates and internal ethylene concentration during the shelf life. Respiration rates increased in the late-harvested fruit for the shelf life period with/without 1-MCP treatment. The 1-MCP-treated fruit was approximately 10 N firmer than fruit not treated with 1-MCP at an early harvest for the entire shelf life duration. Peroxidase activity and percent change in electrical conductivity in the flesh were elevated in late-harvested fruit for the shelf life duration, whereas polyphenol oxidase activities were found to be stimulated by 1-MCP treatment, regardless of harvest time. Late-harvested fruit treated with 1-MCP exhibited increased susceptibility to flesh browning during shelf life, mostly due to reduction of the antioxidant defense mechanism of the fruits to stress in extending storage life, increasing polyphenol oxidase (PPO) activity and electrolyte leakage rate.
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Zhang, Li-Xin, and Robert E. Paull. "Ripening Behavior of Papaya Genotypes." HortScience 25, no. 4 (April 1990): 454–55. http://dx.doi.org/10.21273/hortsci.25.4.454.
Повний текст джерелаАнотація:
Four papaya (Carica papaya L.) lines that may have commercial value were surveyed for variability in ripening characteristics. Skin and flesh yellowing, fruit softening, respiration rate, and ethylene production were compared. Skin yellowing and flesh softening followed a similar sigmoid pattern for all lines. However, the temporal relationship between skin yellowing and flesh softening differed among the lines. Fruit from lines RL-1-3 and RL-1-12 did not begin to soften until the skin was 80% yellow, compared to 40% yellow for the commercial cultivars Kapoho and Sunrise. Fruit from RL-1-3 and RL-1-12 took 12 and 16 days, respectively, to reach 100% yellow from color break, which was two to three times as long as that of `Kapoho' and `Sunrise' at 22C. All lines showed typical climacteric respiration and ethylene patterns. The time between the start of skin yellowing and the rise in respiration varied from ≈2 days in `Kapoho' and `Sunrise' to ≈4 days in line RL-1-3 and 8 days in line RL-1-12. The respiratory peak was greatly reduced in RL-1-12. The patterns of softening in lines RL-1-3 and RL-1-12 differed from `Kapoho' and `Sunrise': RL-1-3 softened slowly, but reached similar firmness values to other lines 4 days after 100% yellow skin color; RL-1-12 had a much slower rate of softening and the fruit were still firm 4 days after the fruit reached 100% yellow. The ripening patterns of line RL-1-3 and RL-1-12 could be useful in postharvest handling and provide material for studying the genetic control of fruit softening.
32
Zhang, Binbin, Xingxing Chen, Na Wang, Shaolei Guo, Weibing Jiang, Mingliang Yu, and Ruijuan Ma. "Effects of Harvest Maturity on the Fruit Quality of Different Flesh-Type Peach Stored at Near-Freezing Point Temperature." Foods 11, no. 15 (July 24, 2022): 2200. http://dx.doi.org/10.3390/foods11152200.
Повний текст джерелаАнотація:
To investigate the peach fruit flesh types (soft-melting, hard-melting, stonyhard and non-melting) and harvest maturity level suitable for near-freezing temperature storage (NFTS), eight peach cultivars that had four flesh types were used as test materials. Changes in fruit respiration intensity and ethylene release rates, as well as the differences in quality indexes, such as soluble solids content (SSC), firmness, color difference, pigment content, soluble sugar and organic acid component content, of three fruit maturity levels (70%, 80% and 90% maturity) under NFTS conditions were analyzed and compared. The fruit quality indexes of peach having different maturity levels and flesh types changed little during NFTS. The SSC and total sugar content of hard-melting and stonyhard peach fruit were higher than those of other flesh types during NFTS. Those fruit maintained greater firmness at the end of the storage period. The differences in respiration intensity and ethylene release rate were small, but for fruit coloring, hard-melting fruit performed better than stonyhard fruit. The 80%, compared with the 90%, maturity stage maintained more fruit moisture, had less fruit mass loss and maintained a greater edible firmness. It effectively impeded the fruit senescence process and was the most suitable maturity for NFTS. Thus, the hard-melting peach maintained the highest commercial value and desirable storage characteristics under NFTS conditions, and its 80% maturity level was the most suitable for NFTS.
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Rajapakse, Nihal C., Nigel H. Banks, Errol W. Hewett, and Donald J. Cleland. "Development of Oxygen Concentration Gradients in Flesh Tissues of Bulky Plant Organs." Journal of the American Society for Horticultural Science 115, no. 5 (September 1990): 793–97. http://dx.doi.org/10.21273/jashs.115.5.793.
Повний текст джерелаАнотація:
Steady-state oxygen diffusion in flesh of apples (Malus domestics Borkh. cvs. Braeburn and Cox's Orange Pippin), Asian pears (Pyrus serotina Rehder. cvs. Hosui and Kosui), and nectarines [Prunus persica (L.) Batsch. cvs. Red Gold and Sunglo] was studied using a nondestructive method at 20C. Fruit flesh was found to exert a significant resistance to O2 diffusion resulting in measurable O2 gradients between tissues immediately beneath the skin and those at the fruit center for all these fruits. The magnitude of these O2 gradients varied between crops and cultivars and depended on the respiration rate and on effective O2 diffusivity in fruit flesh (De). Values of Dc varied with the cultivar and were broadly consistent with intercellular space volume. The range of De values obtained suggested that 02 diffusion in fruit flesh takes place in a combination of series and parallel modes in the intercellular space and fluid/solid matrix of the flesh. The results imply that O2 diffusivity in flesh tissues must be taken into consideration in the determination of critical external O2 level in controlled/modified atmosphere (CA/MA) storage.
34
Brovelli, Ernesto A., Jeffrey K. Brecht, Wayne B. Sherman, and Charles A. Sims. "A Contrast in Ethylene Production and Respiration between Melting- and Nonmelting-flesh Peaches." HortScience 33, no. 3 (June 1998): 468e—468. http://dx.doi.org/10.21273/hortsci.33.3.468e.
Повний текст джерелаАнотація:
A connection between ethylene production and the melting trait in peaches has been reported by other authors. In our study, we refute the notion that ethylene production levels in nonmelting-flesh (NMF) peach (Prunus persica L.) fruit are normally lower than those in melting-flesh (MF) fruit. While in fact during ripening NMF fruit (`Oro A' and FL 86-28C) reached lower firmness levels than MF (FL 90-20 and `TropicBeauty') fruit did, NMF fruit produced consistently higher levels of ethylene than MF counterparts. In both MF and NMF genotypes, fruit from later harvests were in a more advanced phase of their ethylene production and respiratory drift than those from earlier harvests. Fruit size did not necessarily influence levels of respiration or ethylene production. However, when fruit from different sizes had different initial ethylene production rates, those differences were maintained later in other phases of the ethylene production pattern.
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Brecht, J. K., K. Cordasco, and W. B. Sherman. "175 Comparison of Suitability of Nonmelting and Melting Flesh Peach Cultivars for Fresh-cut." HortScience 35, no. 3 (June 2000): 420D—421. http://dx.doi.org/10.21273/hortsci.35.3.420d.
Повний текст джерелаАнотація:
Two nonmelting flesh (`GUFprince' and `UF2000') and two melting flesh (`Tropic Beauty' and `Rayon') peach cultivars were segregated into ripeness categories at harvest according to initial flesh firmness and prepared as fresh-cut slices as described in Gorny et al. (HortScience 33:110–113), except that there were no “overripe” (0-13 N flesh firmness) stage nonmelting flesh fruit. Slices were stored at 1, 5, or 10 °C for 8 days and were evaluated for visual and taste quality, flesh firmness and color, and respiration and ethylene production rates every other day during storage. The optimal ripeness for preparing fresh-cut slices from the melting flesh cultivars was the “ripe” (13-27 N flesh firmness) stage; less-ripe melting flesh slices did not ripen at 1 or 5 °C and riper melting flesh slices and those held at 10 °C softened excessively, became discolored, and decayed. The optimal ripeness stage for the nonmelting flesh cultivars was 40-53 N flesh firmness, which corresponded to physiologically ripe (climacteric rise) for nonmelting flesh fruit, but melting flesh fruit at that firmenss were physiologically only mature-green (preclimacteric). Storage of nonmelting flesh slices was limited by surface desiccation at 1 °C, and by flesh discoloration at 5 and 10 °C, which was more severe in riper slices. The best storage temperature for both fruit genotypes was 1 °C, which prevented discoloration and decay over the 8-day storage period. Nonmelting flesh peach cultivars are better suited for fresh-cut processing than melting flesh cultivars because their firmer texture allows the use of riper fruit with better flavor than the less ripe fruit that must be used for fresh-cut melting flesh peaches.
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Rudell, D. R., D. S. Mattinson, J. K. Fellman, and J. P. Mattheis. "The Progression of Ethylene Production and Respiration in the Tissues of Ripening `Fuji' Apple Fruit." HortScience 35, no. 7 (December 2000): 1300–1303. http://dx.doi.org/10.21273/hortsci.35.7.1300.
Повний текст джерелаАнотація:
`Fuji' apple (Malus ×domestica Borkh.) fruits were harvested periodically prior to and during fruit ripening. Ethylene evolution and respiration rates of skin, hypanthial, and carpellary tissue was determined in each fruit. Additionally, whole fruits were used for analyses of internal ethylene concentration, volatile evolution, starch content, flesh firmness, and soluble solids content. Ethylene production was greatest in the carpellary tissue at all sampling dates except the one occurring just before the rise in whole fruit internal ethylene concentration, when production in the skin and carpellary tissue was similar. Respiration was always highest in the skin, in which the climacteric rise was most drastic. Higher ethylene production in the carpellary tissue of pre- and postclimacteric fruit and higher respiration in the skin tissue, including a noticeable climacteric rise, is indicative of a ripening initiation signal originating and/or transduced through the carpels to the rest of the fruit.
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Yusuf, Nurul Arfiyanti, Nurul Sari Pandewa, Vilia Payangan, and Diaz Permata. "Formulasi sabun mandi cair dari daging putih buah semangka (Citrullus lanatus)." Sasambo Journal of Pharmacy 2, no. 2 (September 30, 2021): 55–59. http://dx.doi.org/10.29303/sjp.v2i2.113.
Повний текст джерелаАнотація:
White flesh watermelon (Citrullus lanatus) is known to contain alkaloids, flavonoids, tannins and polyphenols. Research conducted by Rimando proves that watermelon rind contains the amino acid citrulline reaching 60% which is important in increasing levels of nitric oxide which is a regulator of blood flow, muscle energy metabolism, and mitochondrial respiration during exercise. This study aims to formulate bath soap from watermelon waste that meets the requirements with variations in the concentration of watermelon flesh extract (3%; 6%; 9%). Watermelon flesh extract was extracted by maceration process using 70% ethanol. Evaluations were carried out in the form of organoleptic, pH, free of alkali, high foam and density. The results showed that the three formulas were formulas that met the requirements according to SNI standards based on pH test, free alkali, foam height, and density.
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KRAMER, B., J. WUNDERLICH, and P. MURANYI. "Pulsed Light Decontamination of Endive Salad and Mung Bean Sprouts and Impact on Color and Respiration Activity." Journal of Food Protection 78, no. 2 (February 1, 2015): 340–48. http://dx.doi.org/10.4315/0362-028x.jfp-14-262.
Повний текст джерелаАнотація:
The objective of this study was the determination of the efficiency of pulsed light (PL) treatments for the decontamination of endive salad and mung bean sprouts, as well as the assessment of quality changes in relation to discoloration and alteration of respiration activity. Produce samples were artificially inoculated with two bacterial test strains Escherichia coli (DSM 498) and Listeria innocua (DSM 20649) and exposed to PL at different energy doses. The inactivation efficiency with regard to the naturally occurring microbiota was also investigated. Besides microbiological investigations, color changes were determined as well as the produce respiration during chilled storage. The results indicated that inactivation of more than 2 log was possible with one flash in the case of fresh-cut salad, while the reduction on mung bean sprouts was limited to approximately 1.6 log with one flash, irrespective if the natural flora or inoculated E. coli or L. innocua were considered. The UV part of the PL proved to be exclusively responsible for the inactivation of microorganisms. Significant lower levels of microbial counts of treated compared with untreated samples were maintained for up to 6 days. In the case of endive salad, a dose-dependent progressive discoloration and increase in respiration was diminished by applying optical bandpass filters, which only slightly affected the inactivation efficiency. In contrast, PL treatments showed a positive effect on color and general appearance of mung bean sprouts, while the respiration was almost unaffected. However, care must be taken with regard to efficiency-limiting matrix effects and impact on food quality. These aspects have to be assessed for each treated product. The integration of PL in industrial food processing plants could be an alternative way to improve the microbial quality of fresh produce, and therefore have a positive impact on public health by reducing the risk of contaminations with pathogenic bacteria.
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Akinbolu, A., D. J. Huber, G. J. Hochmuth, and O. C. Aworh. "Influence of Potassium (K) and Cultivar on Watermelon Quality." HortScience 30, no. 4 (July 1995): 823D—823. http://dx.doi.org/10.21273/hortsci.30.4.823d.
Повний текст джерелаАнотація:
The influence of potassium (K) on respiratory behavior, flesh firmness, and internal color of watermelon (Citrullus lanatus) was studied. Two cultivars (Crimson Sweet and Sangria) were planted at the Univ. of Florida research station, Gainesville. The fruits from both cultivars were harvested at two different stages of maturity (25 days and 35 days after anthesis). Respiration and ethylene production were measured using gas chromatography under a static system. The internal color was measured by a colorimeter, while the flesh and rind firmness were measured by a instron Universal pressure tester. Carbon dioxide and ethylene production were non-climacteric in behavior and were not greatly affected by K treatment or cultivar.
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Chene, Guiwen, Carlos Crisosto, and David Garner. "239 RESPONSE OF KIWIFRUIT SOFTENING TO ETHYLENE APPLICATION." HortScience 29, no. 5 (May 1994): 463f—463. http://dx.doi.org/10.21273/hortsci.29.5.463f.
Повний текст джерелаАнотація:
During the 1993 and 1994 seasons, the response of Kiwifruit (Actinidia deliciosa var. Hayward) flesh softening to exogenous ethylene applications was studied on fruit collected weekly from cold storage and directly from the vines. Fruit samples from both sources, were induced to ripen with and without ethylene preconditioning treatment (10 ppm, 24h at 0C). During the first 3 weeks of fruit collection, flesh firmness decreased and SSC accumulation increased faster in ethylene treated kiwifruit than in the untreated. After this period, when kiwifruit had close to 9 pounds flesh firmness, ethylene treated and untreated kiwifruit softened at the same rate. Ethylene treatment did not enhance kiwifruit CO2 and ethylene production except at the first harvest time. Furthermore, ethylene treated kiwifruit did not have higher respiration and ethylene rates than untreated kiwifruit when measured at 0, 5 and 20C.
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Abdul-Baki, Aref A., and Theophanes Solomos. "Diffusivity of Carbon Dioxide through the Skin and Flesh of `Russet Burbank' Potato Tubers." Journal of the American Society for Horticultural Science 119, no. 4 (July 1994): 742–46. http://dx.doi.org/10.21273/jashs.119.4.742.
Повний текст джерелаАнотація:
The diffusion coefficient of CO2 in `Russet Burbank' potato (Solanum tuberosum L.) tubers was determined under steady-state conditions at 10 and 27C. The data showed that the skin is the main barrier to gas diffusion, with an average diffusion coefficient of 6.57 × 10-7 and 7.61 × 10-7 cm·s-1 at 10 and 27C, respectively. The flesh also presents an appreciable barrier to gas diffusion. The average diffusion coefficient of CO2 in the flesh was 2.00 × 10-4 and 2.24 × 10-4 cm·s-1 at 10 and 27C, respectively. Under regular storage conditions, the tuber is well aerated and the concentration of O2 at the center of the tuber is sufficient to maintain aerobic respiration.
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Pavanello, Elizandra Pivotto, Auri Brackmann, Ivan Francisco Dressler da Costa, Vanderlei Both, and Vagner Ludwig. "Use of sodium metasilicate for management of peach brown rot." Pesquisa Agropecuária Tropical 46, no. 3 (September 2016): 245–53. http://dx.doi.org/10.1590/1983-40632016v4641221.
Повний текст джерелаАнотація:
ABSTRACT Peach brown rot, caused by the Monilinia fructicola fungus, is the main disease affecting peach crops, and it is mainly controlled via frequent fungicide applications. This study aimed at searching for alternatives to the intensive use of chemicals, evaluating silicon doses to control pre and postharvest peach brown rot and their influence on maturation parameters and fruit quality. Treatments consisted of control (water) and sodium metasilicate doses (2 g L-1, 4 g L-1, 6 g L-1, 8 g L-1 and 10 g L-1 of water). The following assessments were made: spore germination and in vitro mycelial growth, brown rot incidence, soluble solids, titratable acidity, flesh firmness, total polyphenol content and fruit ethylene production and respiration rate. The 2 g L-1 dose reduced spore germination by 95 %. Doses of 6 g L-1 and 8 g L-1 satisfactorily reduced the disease incidence in the field, with 77 % and 89.2 % control, respectively. Sodium metasilicate resulted in the maintenance of great fruit firmness, reduced respiration and ethylene production and increased total polyphenol synthesis, but it did not influence the titratable acidity or soluble solids. Applying 6 g L-1 may potentially control pre and postharvest peach brown rot, besides increasing the total polyphenol synthesis and maintaining a higher flesh firmness.
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Zhou, Lili, and Robert E. Paull. "Sucrose Metabolism During Papaya (Carica papaya) Fruit Growth and Ripening." Journal of the American Society for Horticultural Science 126, no. 3 (May 2001): 351–57. http://dx.doi.org/10.21273/jashs.126.3.351.
Повний текст джерелаАнотація:
Papaya (Carica papaya L.) fruit flesh and seed growth, fruit respiration, sugar accumulation, and the activities of sucrose phosphate synthase (SPS), sucrose synthase (SS), and acid invertase (AI) were determined from anthesis for ≈150 days after anthesis (DAA), the full ripe stage. Sugar began to accumulate in the fruit flesh between 100 and 140 DAA, after seed maturation had occurred. SPS activity remained low throughout fruit development. The activity of SS was high 14 DAA and decreased to less than one-fourth within 56 DAA, then remained constant during the remainder of fruit development. AI activity was low in young fruit and began to increase 90 DAA and reached a peak more than 10-fold higher, 125 DAA, as sugar accumulated in the flesh. Results suggest that SS and AI are two major enzymes that may determine papaya fruit sink strength in the early and late fruit development phases, respectively. AI activity paralleled sugar accumulation and may be involved in phloem sugar unloading.
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Fallahi, Esmaeil, W. Michael Colt, Craig R. Baird, Bahar Fallahi, and Ik-Jo Chun. "Influence of Nitrogen and Bagging on Fruit Quality and Mineral Concentrations of `BC-2 Fuji' Apple." HortTechnology 11, no. 3 (January 2001): 462–66. http://dx.doi.org/10.21273/horttech.11.3.462.
Повний текст джерелаАнотація:
The influence of three rates of nitrogen (N) and fruit bagging on fruit peel and flesh mineral concentrations and fruit quality in `BC-2 Fuji' apple (Malus domestica Borkh.) trees on Malling 9 (M.9) was studied. Increasing N application decreased fruit peel red color, fruit N, iron (Fe), and manganese (Mn). Fruit from trees receiving 10.72 oz (303.9 g) N per year had higher evolved ethylene and respiration during poststorage ripening tests. Bagging of fruit reduced fruit peel red color, soluble solids concentrations (SSC), and dry weight as compared to nonbagged fruit. Bagged fruit had higher N, potassium (K), and copper (Cu) than nonbagged fruit. Fruit peel had a greater percentage of dry weight, and higher concentrations of all tested minerals compared to fruit flesh.
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Giehl, Ricardo Fabiano Hettwer, Ivan Sestari, Ana Cristina Eisermann, and Auri Brackmann. "Thidiazuron affects the quality of 'Gala' apples stored under controlled atmosphere." Ciência Rural 40, no. 4 (April 2010): 813–19. http://dx.doi.org/10.1590/s0103-84782010000400011.
Повний текст джерелаАнотація:
This work was carried out aiming to evaluate the effect of thidiazuron (TDZ) on the quality of 'Gala' apples stored under controlled atmosphere (CA) conditions. Plants were sprayed at full bloom with TDZ at 0, 10, 20, or 40g ha-1 (a.i.). Harvested fruits were then stored in CA with 1.0+2.5, 1.5+2.5 and 1.5+5.0 (kPa O2+kPa CO2), both at 0.5°C. In addition, the partial pressure of 1.5kPa of O2+2.5kPa of CO2 was also evaluated at -0.5°C. Higher flesh firmness and titratable acidity was obtained by applying 20 or 40g ha-1 TDZ. Furthermore, these TDZ doses decreased the respiration rate as well as the occurrence of flesh breakdown, mealiness and decay. The application of TDZ at doses ranging from 20 to 40g ha-1 maintains higher fruit quality for up to 8 months under CA. In addition, the storage of 'Gala' apples under CA with 1.0kPa O2+2.5kPa CO2 at 0.5°C results in higher flesh firmness and titratable acidity. Moreover, this CA condition reduces the incidence of flesh breakdown, mealiness and postharvest decay in 'Gala' apple fruits.
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ten Veldhuis, Marie-Claire, Gennady Ananyev, and G. Charles Dismukes. "Symbiosis extended: exchange of photosynthetic O2 and fungal-respired CO2 mutually power metabolism of lichen symbionts." Photosynthesis Research 143, no. 3 (December 31, 2019): 287–99. http://dx.doi.org/10.1007/s11120-019-00702-0.
Повний текст джерелаАнотація:
AbstractLichens are a symbiosis between a fungus and one or more photosynthetic microorganisms that enables the symbionts to thrive in places and conditions they could not compete independently. Exchanges of water and sugars between the symbionts are the established mechanisms that support lichen symbiosis. Herein, we present a new linkage between algal photosynthesis and fungal respiration in lichen Flavoparmelia caperata that extends the physiological nature of symbiotic co-dependent metabolisms, mutually boosting energy conversion rates in both symbionts. Measurements of electron transport by oximetry show that photosynthetic O2 is consumed internally by fungal respiration. At low light intensity, very low levels of O2 are released, while photosynthetic electron transport from water oxidation is normal as shown by intrinsic chlorophyll variable fluorescence yield (period-4 oscillations in flash-induced Fv/Fm). The rate of algal O2 production increases following consecutive series of illumination periods, at low and with limited saturation at high light intensities, in contrast to light saturation in free-living algae. We attribute this effect to arise from the availability of more CO2 produced by fungal respiration of photosynthetically generated sugars. We conclude that the lichen symbionts are metabolically coupled by energy conversion through exchange of terminal electron donors and acceptors used in both photosynthesis and fungal respiration. Algal sugars and O2 are consumed by the fungal symbiont, while fungal delivered CO2 is consumed by the alga.
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Feng, Gaomin, Beibei Liu, Jinghang Li, Tianlei Cheng, Zhanglong Huang, Xianhua Wang, and Heping (Peace) Cheng. "Mitoflash biogenesis and its role in the autoregulation of mitochondrial proton electrochemical potential." Journal of General Physiology 151, no. 6 (March 15, 2019): 727–37. http://dx.doi.org/10.1085/jgp.201812176.
Повний текст джерелаАнотація:
Respiring mitochondria undergo an intermittent electrical and chemical excitation called mitochondrial flash (mitoflash), which transiently uncouples mitochondrial respiration from ATP production. How a mitoflash is generated and what specific role it plays in bioenergetics remain incompletely understood. Here, we investigate mitoflash biogenesis in isolated cardiac mitochondria by varying the respiratory states and substrate supply and by dissecting the involvement of different electron transfer chain (ETC) complexes. We find that robust mitoflash activity occurs once mitochondria are electrochemically charged by state II/IV respiration (i.e., no ATP synthesis at Complex V), regardless of the substrate entry site (Complex I, Complex II, or Complex IV). Inhibiting forward electron transfer abolishes, while blocking reverse electron transfer generally augments, mitoflash production. Switching from state II/IV to state III respiration, to allow for ATP synthesis at Complex V, markedly diminishes mitoflash activity. Intriguingly, when mitochondria are electrochemically charged by the ATPase activity of Complex V, mitoflashes are generated independently of ETC activity. These findings suggest that mitoflash biogenesis is mechanistically linked to the build up of mitochondrial electrochemical potential rather than ETC activity alone, and may functionally counteract overcharging of the mitochondria and hence serve as an autoregulator of mitochondrial proton electrochemical potential.
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Wang, T., A. R. Gonzalez, E. E. Gbur, and J. M. Aselage. "CHANGES IN ORGANIC ACIDS AND OTHER COMPOSITIONAL AND PHYSIOLOGICAL ATTRIBUTES OF PEACHES DUE TO CHILLING INJURY." HortScience 27, no. 11 (November 1992): 1167c—1167. http://dx.doi.org/10.21273/hortsci.27.11.1167c.
Повний текст джерелаАнотація:
Babygold 5 (BG5) and Redhaven (RDH) peaches at maturity 4 were held at 2.3°C for 0, 2 and 4 weeks. After each cold storage treatment half of the fruit sample was evaluated; the other half was ripened for 8 days at 21°C and respiration was measured daily. The evaluations on both samples were for malic, citric and quinic acids, titratable acidity (TA), soluble solids (SS) and flesh firmness. Malic acid in ripened BG5 and RDH Fruits increased relative to their unripened counterpart over the cold storage time; citric acid increased in BG5, decreased in RDH; quinic acid decreased in both cultivars; TA increased; SS decreased in BG5, did not change in RDH; flesh firmness increased in BG5, did not change in RDH. Respiratory rate increased with cold storge time in both cultivars. Overall, BG5 showed more susceptibility to chilling than RDH.
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Brovelli, Ernesto A., Jeffrey K. Brecht, Wayne B. Sherman, and Charles A. Sims. "Nonmelting-flesh Trait in Peaches Is Not Related to Low Ethylene Production Rates." HortScience 34, no. 2 (April 1999): 313–15. http://dx.doi.org/10.21273/hortsci.34.2.313.
Повний текст джерелаАнотація:
The notion that ethylene production levels in nonmelting-flesh (NMF) peach (Prunus persica L.) fruit are normally lower than those in melting-flesh (MF) fruit is refuted in our study. In fact, NMF fruit (`Oro A' and FL 86-28C) usually produced higher levels of ethylene than did MF fruit (FL 90-20 and `TropicBeauty'). In both MF and NMF peaches, the rate of ethylene production, rather than the respiration rate, provided a good indication of the developmental stage of the fruit at harvest. Ethylene content in fruit on the tree followed a climacteric pattern, with the level in `Oro A' (NMF) and FL 90-20 (MF) peaking at 50 and 12 μL·L–1, respectively. The respiratory climacteric was not apparent in either `Oro A' or FL 90-20, and levels of CO2 were similar in both genotypes.
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Limbanyen, Arunya, Jeffrey K. Brecht, Steven A. Sargent, and Jerry A. Bartz. "Fresh-cut Mango Fruit Slices." HortScience 33, no. 3 (June 1998): 457b—457. http://dx.doi.org/10.21273/hortsci.33.3.457b.
Повний текст джерелаАнотація:
Preparation and handling procedures for fresh-cut mango slices were developed using `Tommy Atkins', `Haden', and `Palmer' mangoes. Fruit with yellow flesh color (no green color remaining) were optimum maturity for fresh-cut in terms of maintenance of acceptable appearance, texture, and taste; riper fruit developed flesh breakdown and more browning. Postharvest life of fresh-cut mango at 5 °C was 8 to 10 d with no evidence of chilling injury and was limited by flesh browning and loss of firmness. Respiration rates ranged from 32 to 40 mg CO2/kg per hr and ethylene production was typically ≤0.1 μl·kg–1·hr–1. The SSC changed little during storage, while pH varied from 3.5 to 4.8 and TA typically declined by 30% to 40%. Peeling to a depth of at least 2 mm and trimming flesh near the stem scar was necessary to minimize browning. Imported fruit that had been heat-treated for insect quarantine showed more severe browning than Florida fruit that had not been heat-treated. Preparation in aseptic conditions and dipping fruit in a 100 ppm NaOCl solution at pH 7 before and after peeling protected against decay during storage but dipping in chlorine after slicing without removal of excess liquid resulted in flesh translucency and breakdown. Dipping in 1% CaCl2 solution had no effect on flesh firmness (Instron) or browning. Storage in an unvented plastic clamshell container, which developed an atmosphere of 2.25% CO2 plus 19% O2, did not improve shelf life, but a MA of 10% CO2 plus 10% O2 was subjectively judged to slow browning and softening and resulted in no off flavor compared to air storage.