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Gustavo A. Slafer - One of the best experts on this subject based on the ideXlab platform.
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Genotypic variability and response to water stress of pre- and post-Anthesis phases in triticale
European Journal of Agronomy, 2008Co-Authors: Gaspar Estrada-campuzano, Daniel J Miralles, Gustavo A. SlaferAbstract:Abstract A better understanding of responsiveness of time to Anthesis to water stress in triticale and wheat might help to explain their differences in performance under stress and to identify which attributes or components of time to Anthesis are most affected. Three experiments were carried out during the 2004 and 2005 growing seasons to (i) evaluate genotypic variability in phenology responsiveness to drought in triticale and to (ii) explore the variation in the duration of pre-Anthesis phases occurring before and after the onset of stem elongation as well as their responsiveness to water stress. Important variation was found among triticale cultivars on time to Anthesis, allowing classification of cultivars into long, intermediate and short cycle. Differences in the duration of the stem elongation phase (i.e. from terminal spikelet initiation (TS) to Anthesis (ANT)) were as high as 200 °Cd for cultivars with similar time to flowering. Although water stress reduced the time to Anthesis (in average by ca. 125 °Cd), cultivars showed a differential responsiveness to drought in phases occurring before or after TS. Some cultivars that were highly sensitive to drought in the emergence (Eme)–TS phase were insensitive in the phase TS–ANT and vice-versa. Water shortage tended to reduce the grain filling period and was most evident when a Mediterranean environment treatment was simulated.
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Grain weight and grain number responsiveness to pre-Anthesis temperature in wheat, barley and triticale
Field Crops Research, 2007Co-Authors: Cristina Cecilia Ugarte, D. F. Calderini, Gustavo A. SlaferAbstract:In temperate cereals are commonly accepted that determination of grain number (GN) and grain weight (GW) scarcely overlap during the crop cycle. However, the assumption that GW is determined exclusively after Anthesis needs to be critically reviewed in the light of reports published over the few years where temperature treatments imposed before Anthesis decreased GW of bread wheat. Although these evidences suggest that both GW and GN could be affected by environmental conditions before Anthesis little is known about the effect of pre-Anthesis temperature on these two main yield components in wheat, barley and triticale at field conditions. In addition, the effect of temperature on GW and GN at different stages prior to Anthesis has been scarcely evaluated. The objectives of the current study were: (i) to evaluate the overall response, and specific differences, of GN and GW to pre-Anthesis temperature, and (ii) to study the effect of different timings of high temperature at pre-Anthesis on GN and GW in wheat, barley and triticale. Three fully irrigated field experiments were carried out in three successive seasons. At each season, a wheat, barley and triticale high yielding cultivar was evaluated at three temperature regimes: control, and two timings of heating before Anthesis. During the first and second seasons, the timings of heating were booting-Anthesis and heading-Anthesis. In the thirst season, the timings were beginning of stem elongation-booting and booting-Anthesis. Plots were arranged in a split-plot design with three replicates, where the main plot was assigned to thermal regime and the sub-plots to crop species. To apply heat, transparent chambers equipped with thermostatically controlled electric heaters were used. The thermal regime was controlled by sensors connected to a temperature regulator and recorded using data loggers. Temperature within the chambers was stable across developmental stages, crops, and seasons; it averaged 5.5 °C higher than air temperature. Thermal treatments consistently reduced grain yield (p < 0.05), the magnitude of the effect ranged between 5 and 52%. The highest effect was found when temperature increased during stem elongation (yield decrease: 46%), lowest when treatments were imposed during heading-Anthesis (15%) and intermediate for treatments imposed during booting-Anthesis (27%). Most effects of thermal treatments on yield were due to parallel effects on GN. However, thermal treatments significantly (p < 0.05) decreased GW during the three seasons. The most effecting treatment on GW was when the crops were heated during the B-A period, i.e. GW decreased up to 23%.
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pre Anthesis development and number of fertile florets in wheat as affected by photoperiod sensitivity genes ppd d1 and ppd b1
Euphytica, 2006Co-Authors: Fernanda G Gonzalez, Gustavo A. Slafer, Daniel J MirallesAbstract:Lengthening the late reproductive phase (LRP) of stem elongation in wheat (Triticum aestivumL.), by changing its photoperiod sensitivity independently of the preceding phases, would improve the yield potential through increasing spike weight and the number of fertile florets at Anthesis. This paper presents results of a two-year field experiment designed to determine the impact of Ppd-D1and Ppd-B1on (i) the duration of three pre-Anthesis developmental phases, and (ii) spike weight and the number of fertile florets at Anthesis under two photoperiods during the LRP (natural and an extension of six hours over that). Near isogenic lines of Mercia and single chromosome recombinant lines of Cappelle Desprez were used. Under natural photoperiod, Ppd-D1hastened time to Anthesis ca. 500∘C d in both backgrounds by reducing each of the three pre-Anthesis phases. Ppd-B1hastened the time to Anthesis under natural photoperiod by 178∘C d, mainly by reducing the early reproductive phase. The response to photoperiod of the LRP under extended daylength depended on the Ppdlocus present: Ppd-D1was insensitive while Ppd-B1and the recessive controls were sensitive. For all lines, photoperiod treatments and years, the number of fertile florets was associated with spike dry weight at Anthesis (R 2≅ 80%, p< 0.01) which, in turn, was positively related to the intercepted radiation accumulated during the LRP (R 2 45%, p< 0.05). Changing the duration of the LRP through extended photoperiod or through Ppd-D1produced similar results in both backgrounds and years. Thus, altering the duration of the LRP by manipulating photoperiod sensitivity may be an alternative to changing the fertile floret number in wheat. Nevertheless, as no particular allele was responsible for the photoperiod sensitivity only during the LRP, new alleles should be studied to identify the control of photoperiod sensitivity of individual phases to fine-tune the pre-Anthesis wheat development.
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The Importance of the Period Immediately Preceding Anthesis for Grain Weight Determination in Wheat
Euphytica, 2001Co-Authors: D. F. Calderini, Roxana Savin, L. G. Abeledo, Matthew P. Reynolds, Gustavo A. SlaferAbstract:Although individual grain weight is an important source of variation forgrain yield, there is still poor understanding of the causes determining finalgrain weight. Almost all studies conducted for understanding thedeterminants of grain weight have been focused on the post-Anthesis period.However, there is important evidence that pre-Anthesis conditions couldalso modify final grain weight. Three experiments including different sowingdates, genotypes and temperature regimes between booting and Anthesis,were carried out in Argentina and Mexico to analyse the effect oftemperature and associated traits during the pre- and post-Anthesis periodson grain weight under field conditions. In these experiments final grainweight could not be explained by average or maximum temperature duringthe post-Anthesis period. However, average temperature between bootingand Anthesis was closely related to the observed grain weight differences,probably as a consequence of the effects of this factor on carpel growth.Differences in grain weight between genotypes and grain position weresuccessfully explained by differences in carpel weight at Anthesis. Theseresults suggest that our knowledge to determine grain weight could improveif the immediately pre-Anthesis period conditions were taken into account.
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Effect of temperature and carpel size during pre-Anthesis on potential grain weight in wheat
The Journal of Agricultural Science, 1999Co-Authors: D. F. Calderini, Roxana Savin, L. G. Abeledo, Gustavo A. SlaferAbstract:The effect of environmental conditions immediately before Anthesis on potential grain weight was investigated in wheat at the experimental field of the Faculty of Agronomy (University of Buenos Aires, Argentina) during 1995 and 1996. Plants of two cultivars of wheat were grown in two environments (two contrasting sowing dates) to provide different background temperature conditions. In these environments, transparent boxes were installed covering the spikes in order to increase spike temperature for a short period (c. 6 days) immediately before Anthesis, i.e. between ear emergence and Anthesis. In both environments, transparent boxes increased mean temperatures by at least 3n8 mC. These increases were almost entirely due to the changes in maximum temperatures because minimum temperatures were little affected. Final grain weight was significantly reduced by higher temperature during the ear emergence–Anthesis period. It is possible that this reduction could be mediated by the effect of the heat treatment on carpel weight at Anthesis because a curvilinear association between final grain weight and carpel weight at Anthesis was found. This curvilinear association may also indicate a threshold carpel weight for maximizing grain weight.
Fulai Liu - One of the best experts on this subject based on the ideXlab platform.
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drought priming at vegetative growth stage enhances nitrogen use efficiency under post Anthesis drought and heat stress in wheat
Journal of Agronomy and Crop Science, 2017Co-Authors: D H Larsen, Shengqun Liu, Xiancan Zhu, Fengbin Song, Fulai LiuAbstract:To study the effects of early drought priming at 5th-leaf stage on grain yield and nitrogen-use efficiency in wheat (Triticum aestivum L.) under post-Anthesis drought and heat stress, wheat plants were first exposed to moderate drought stress (drought priming; that is, the leaf water potential reached ca. −0.9 MPa) at the 5th-leaf stage for 11 days, and leaf water relations and gas exchange rates, grain yield and yield components, and agronomic nitrogen-use efficiency (ANUE) of the primed and non-primed plants under post-Anthesis drought and heat stress were investigated. Compared with the non-primed plants, the drought-primed plants possessed higher leaf water potential and chlorophyll content, and consequently a higher photosynthetic rate during post-Anthesis drought and heat stress. Drought priming also resulted in higher grain yield and ANUE in wheat under post-Anthesis drought and heat stress. Drought priming at vegetative stage improves carbon assimilation and ANUE under post-Anthesis drought and heat stress and their combination in wheat, which might be used as a field management tool to enhance stress tolerance of wheat crops to multiple abiotic stresses in a future drier and warmer climate.
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Changes of transcriptome and proteome are associated with the enhanced post-Anthesis high temperature tolerance induced by pre-Anthesis heat priming in wheat
Plant Growth Regulation, 2015Co-Authors: Caiyun Xin, Xiao Wang, Jian Cai, Fulai Liu, Tingbo Dai, Weixing Cao, Qin Zhou, Dong JiangAbstract:This study was to explore the mechanism of the enhanced tolerance to post-Anthesis high temperature stress induced by pre-Anthesis heat priming in wheat (Triticum aestivum L.). Genome-wide gene expression profiles by Affymetrix Wheat Genome Chip and proteome analysis by 2D electrophoresis and MALDI TOF/TOF were performed in the leaf after pre-Anthesis heat priming and post-Anthesis high temperature stress. Physiological analyses indicated that primed plants showed higher rates of photosynthesis, activities of antioxidant enzymes and lower cell membrane oxidative damage, suggesting a less high temperature damage in the primed plants. 88 gene probes and 8 protein spots were regulated after both pre-Anthesis heat priming and post-Anthesis high temperature stress, and the probes and proteins were expressed differently in primed plants from those in non-primed plants. Transcriptome and proteome analyses revealed up-regulation of the genes that encoded sensing and signaling, heat shock proteins, redox homeostasis, and down-regulation of the genes that encoded metabolism. The up-regulation and down-regulation might play protective roles in coping with the post-Anthesis high temperature stress in the pre-Anthesis heat primed plants compared with non-primed plants. It is concluded that pre-Anthesis heat priming could initiate the acclimation responses at both transcriptome and proteome levels for enhancing heat tolerance at later stages in wheat plants. These results are of primary importance for understanding the effects of multi-heat stress on production of wheat crops in future climate change scenarios.
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Pre-Anthesis high temperature acclimation alleviates the negative effects of post-Anthesis heat stress on stem stored carbohydrates remobilization and grain starch accumulation in wheat
Journal of Cereal Science, 2012Co-Authors: Xiao Wang, Jian Cai, Fulai Liu, Mei Jin, Dong Jiang, Bernd Wollenweber, Tingbo Dai, Weixing CaoAbstract:Abstract The potential role of pre-Anthesis high temperature acclimation in alleviating the negative effects of post-Anthesis heat stress on stem stored carbohydrate remobilization and grain starch accumulation in wheat was investigated. The treatments included no heat-stress (CC), heat stress at pre-Anthesis only (HC), heat at post-Anthesis only (CH), and heat stress at both stages (HH). Post-Anthesis heat stress decreased grain starch content, reduced the content of fructans and depressed activities of related synthesis enzymes of sucrose:sucrose fructosyltransferase and fructan:fructan fructosyltransferase. Interestingly, HH plants had significantly higher grain yield than the CH plants. In addition, post-Anthesis high temperature lowered grain starch content and increased percentages of volume, number and surface area of B-type starch granules in CH and HH than in CC treatment. However, HH plants had much higher starch content, and caused less modified B-type starch granule size indicators than the CH plants. Our results indicated that, compared with the non-acclimated plants, the pre-Anthesis high temperature acclimation effectively enhanced carbohydrate remobilization from stems to grains, led to less changed starch content and starch granule size distribution in grains of wheat under post-Anthesis heat stress.
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Pre-Anthesis high-temperature acclimation alleviates damage to the flag leaf caused by post-Anthesis heat stress in wheat.
Journal of Plant Physiology, 2011Co-Authors: Xiao Wang, Jian Cai, Fulai Liu, Dong Jiang, Tingbo Dai, Weixing CaoAbstract:Abstract The objective of this study was to investigate the effect of pre-Anthesis high-temperature acclimation on leaf physiology of winter wheat in response to post-Anthesis heat stress. The results showed that both pre- and post-Anthesis heat stresses significantly depressed flag leaf photosynthesis and enhanced cell membrane peroxidation, as exemplified by increased O 2 − production rate and reduction in activities of antioxiditave enzymes. However, under post-Anthesis heat stress, plants with pre-Anthesis high-temperature acclimation (HH) showed much higher photosynthetic rates than those without pre-Anthesis high-temperature acclimation (CH). Leaves of HH plants exhibited a higher Chl a/b ratio and lower chlorophyll/carotenoid ratio and superoxide anion radical release rate compared with those of the CH plants. In addition, antioxidant enzyme activities in HH plants were significantly higher than in CH. Coincidently, expressions of photosythesis-responsive gene encoding Rubisco activase B ( RcaB ) and antioxidant enzyme-related genes encoding mitochondrial manganese superoxide dismutase ( Mn-SOD ), chloroplastic Cu/Zn superoxide dismutase ( Cu/Zn-SOD ), catalase ( CAT ) and cytosolic glutathione reductase ( GR ) were all up-regulated under HH, whereas a gene encoding a major chlorophyll a/b-binding protein ( Cab ) was up-regulated by post-Anthesis heat stress at 10 DAA, but was down-regulated at 13 DAA. The changes in the expression levels of the HH plants were more pronounced than those for the CH. Collectively, the results indicated that pre-Anthesis high-temperature acclimation could effectively alleviate the photosynthetic and oxidative damage caused by post-Anthesis heat stress in wheat flag leaves, which was partially attributable to modifications in the expression of the photosythesis-responsive and antioxidant enzymes-related genes.
Shengqun Liu - One of the best experts on this subject based on the ideXlab platform.
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drought priming at vegetative growth stage enhances nitrogen use efficiency under post Anthesis drought and heat stress in wheat
Journal of Agronomy and Crop Science, 2017Co-Authors: D H Larsen, Shengqun Liu, Xiancan Zhu, Fengbin Song, Fulai LiuAbstract:To study the effects of early drought priming at 5th-leaf stage on grain yield and nitrogen-use efficiency in wheat (Triticum aestivum L.) under post-Anthesis drought and heat stress, wheat plants were first exposed to moderate drought stress (drought priming; that is, the leaf water potential reached ca. −0.9 MPa) at the 5th-leaf stage for 11 days, and leaf water relations and gas exchange rates, grain yield and yield components, and agronomic nitrogen-use efficiency (ANUE) of the primed and non-primed plants under post-Anthesis drought and heat stress were investigated. Compared with the non-primed plants, the drought-primed plants possessed higher leaf water potential and chlorophyll content, and consequently a higher photosynthetic rate during post-Anthesis drought and heat stress. Drought priming also resulted in higher grain yield and ANUE in wheat under post-Anthesis drought and heat stress. Drought priming at vegetative stage improves carbon assimilation and ANUE under post-Anthesis drought and heat stress and their combination in wheat, which might be used as a field management tool to enhance stress tolerance of wheat crops to multiple abiotic stresses in a future drier and warmer climate.
Alain Mollier - One of the best experts on this subject based on the ideXlab platform.
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Phosphorus uptake and partitioning in two durum wheat cultivars with contrasting biomass allocation as affected by different P supply during grain filling
Plant and Soil, 2020Co-Authors: Mohamed El Mazlouzi, Christian Morel, Thierry Robert, Alain MollierAbstract:Aims Phosphorus (P) export with harvested grains is a key step of the P cycle in agroecosystems. In wheat, the accumulation of P in grains originates from both exogenous and endogenous P sources. We investigated the effects of different post-Anthesis P supply on P partitioning and P remobilization in two durum wheat cultivars with contrasting biomass allocation. Methods Wheat plants were grown on a complete nutrient solution with sufficient P until Anthesis. Thereafter, half of the plants were deprived of P and the other half was maintained on the complete nutrient solution. P uptake, allocation, remobilization, and traits related to yield and grain P were determined. Results Modifications of post-Anthesis P supply had no effect on grain yield. Grain P concentrations at maturity for deprived P supply ranged from 2.2 to 3.4 mg P g DW^− 1. Without P, net P fluxes to grains essentially came from leaves (35%), roots (28%) and stems (17% ). With P, net P fluxes came mainly from post-antheis P uptake. Conclusions Our results suggest that when the P nutrition of durum wheat is limited after Anthesis, endogenous P remobilization can sustain grain growth with minor yield penalties if the plants are well supplied during vegetative growth.
Walter Kühbauch - One of the best experts on this subject based on the ideXlab platform.
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The utilization of pre‐Anthesis reserves in grain filling of wheat. Assessment by steady‐state 13CO2/12CO2 labelling
Plant Cell and Environment, 1999Co-Authors: Thomas Gebbing, Hans Schnyder, Walter KühbauchAbstract:Significant mobilization of protein and carbohydrates in vegetative plant parts of wheat regularly occurs during grain filling. While this suggests a contribution of reserves to grain filling, the actual efficiency of mobilized assimilate conversion into grain mass (ME) is unknown. In the present study the contribution of pre-Anthesis C (C fixed prior to Anthesis) to grain filling in main stem ears of two spring wheat (Triticum aestivum L.) cultivars was determined by 13 C/ 12 C steady-state labelling. Mobilization of pre-Anthesis C in vegetative plant parts between Anthesis and maturity, and the contributions of water-soluble carbohydrates (WSC) and protein to pre-Anthesis C mobilization were also assessed. Experiments were performed with two levels of N fertilizer supply in each of 2 years. Pre-Anthesis reserves contributed 11‐29% to the total mass of C in grains at maturity. Pre-Anthesis C accumulation in grains was dependent on both the mass of pre-Anthesis C mobilized in aboveground vegetative plant parts (r 2 = 0·87) and ME (defined as g pre-Anthesis C deposited in grains per g pre-Anthesis C mobilized in above-ground vegetative plant parts; r 2 = 0·40). ME varied between 0·48 and 0·75. The effects of years, N fertilizer treatments and cultivars on ME were all related to differences in the fractional contribution of WSC to preAnthesis C mobilization. Multiple regression analysis indicated that C from mobilized pre-Anthesis WSC may be used more efficiently in grain filling than C present in proteins at Anthesis and mobilized during grain filling. Possible causes for variability of ME are discussed.
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the utilization of pre Anthesis reserves in grain filling of wheat assessment by steady state 13co2 12co2 labelling
Plant Cell and Environment, 1999Co-Authors: Thomas Gebbing, Hans Schnyder, Walter KühbauchAbstract:Significant mobilization of protein and carbohydrates in vegetative plant parts of wheat regularly occurs during grain filling. While this suggests a contribution of reserves to grain filling, the actual efficiency of mobilized assimilate conversion into grain mass (ME) is unknown. In the present study the contribution of pre-Anthesis C (C fixed prior to Anthesis) to grain filling in main stem ears of two spring wheat (Triticum aestivum L.) cultivars was determined by 13 C/ 12 C steady-state labelling. Mobilization of pre-Anthesis C in vegetative plant parts between Anthesis and maturity, and the contributions of water-soluble carbohydrates (WSC) and protein to pre-Anthesis C mobilization were also assessed. Experiments were performed with two levels of N fertilizer supply in each of 2 years. Pre-Anthesis reserves contributed 11‐29% to the total mass of C in grains at maturity. Pre-Anthesis C accumulation in grains was dependent on both the mass of pre-Anthesis C mobilized in aboveground vegetative plant parts (r 2 = 0·87) and ME (defined as g pre-Anthesis C deposited in grains per g pre-Anthesis C mobilized in above-ground vegetative plant parts; r 2 = 0·40). ME varied between 0·48 and 0·75. The effects of years, N fertilizer treatments and cultivars on ME were all related to differences in the fractional contribution of WSC to preAnthesis C mobilization. Multiple regression analysis indicated that C from mobilized pre-Anthesis WSC may be used more efficiently in grain filling than C present in proteins at Anthesis and mobilized during grain filling. Possible causes for variability of ME are discussed.
