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F H Andrade - One of the best experts on this subject based on the ideXlab platform.
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maize grain yield components and source sink relationship as affected by the delay in sowing date
Field Crops Research, 2016Co-Authors: Lucas E Bonelli, J P Monzon, Anibal Cerrudo, Roberto H Rizzalli, F H AndradeAbstract:Abstract Delaying maize ( Zea mays L.) sowing date can diminish grain yields through reductions in the number, size and activity of growing grains (sink strength) and/or reductions in the assimilate supply (source capacity) to grains during the grain Filling Period. Whether the source capacity or the sink strength is the limiting factor for grain yield in late sown maize still remains unclear. Understanding source-sink relationships is relevant to optimize crop management practices, to identify critical processes for crop modelling and to develop breeding strategies. The objective of this work was to assess the effect of delays in maize sowing date on grain yield components and on the source-sink relationship during the grain Filling Period. Three well irrigated and fertilized maize field experiments were conducted at Balcarce, Argentina (37° 45′ S, 58° 18′ W; 130 m a.s.l.) during 2009–10; 2010–11 and 2011–12 cropping seasons. Sowing dates ranged from October to January covering a broad range of the seasonal photo-thermal variation. Grain yield was affected by sowing date and varied from 1680 g m −2 (early sowings) to 203 g m −2 (late sowings). Grain number per unit area was reduced proportionally less than weight per grain as sowing date was delayed. Variations in grain yield were related to the harvest index, and were closely associated with dry matter accumulation during the post-silking Period. The variation of source capacity was higher than that of sink strength during the grain Filling Period and the source/sink ratio decreased from early to late sowing dates. Results indicate that crop growth during the grain Filling Period was limited by the sink strength in early sowing dates and by the photosynthetic source capacity in the late ones.
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kernel weight and its response to source manipulations during grain Filling in argentinean maize hybrids released in different decades
Field Crops Research, 2006Co-Authors: Laura Echarte, F H Andrade, Victor O Sadras, P E AbbateAbstract:Abstract Grain yield is greater in newer than in older Argentinean maize ( Zea mays L.) hybrids. Kernel number per plant was the main yield component accounting for grain yield increments. It is not clear, however, how breeding efforts affected kernel weight. The objectives of this work were (i) to characterize kernel weight, kernel weight components (i.e., kernel growth rate and effective grain Filling duration) and ear demand (i.e., the product between kernel number per plant and effective kernel growth rate) in six maize hybrids released in different decades and (ii) to determine whether kernel weight of more recent hybrids is more susceptible than that of older ones to variations in source capacity during the grain Filling Period. Hybrids released between 1965 and 1993 were compared in field experiments in 1995–1996 (Exp. 1) and 2000–2001 (Exp. 2). Exp. 2 included three treatments to increase (crop thinning) or decrease (crop defoliation) the supply of assimilates during grain Filling in comparison to untreated controls. Kernel weight was different among hybrids, but it did not present a clear trend with the year of release. Kernel weight was associated with kernel growth rate. Newer hybrids had larger ear demand than older ones by two distinct mechanisms: a greater kernel number per plant or a large potential kernel weight. Source reductions during the grain Filling Period resulted in larger kernel weight reduction in newer than in older hybrids. This indicates that individual grain weight stability of newer hybrids is lower than that of older hybrids in response to source reductions during the grain Filling Period.
Jianchang Yang - One of the best experts on this subject based on the ideXlab platform.
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Relationships of Ethylene Evolution Rate and 1-Aminocylopropane -1-Carboxylic Acid Concentration in Grains during Filling Period with Appearance Quality of Rice
Elsevier, 2007Co-Authors: Jianchang Yang, Er-hua Chang, Cheng Tang, Hao Zhang, Zhiqin WangAbstract:To elucidate the relationship between ethylene evolution from the grains and the appearance quality of rice, ten different rice genotypes were used to determine the ethylene evolution rate, 1-aminocylopropane-1-carboxylic acid (ACC) concentration in grains during grain Filling and the appearance quality of rice, and the effects of chemical regulators on concentrations of ethylene and ACC in the grains during grain Filling were also investigated to verify the roles of ethylene in the rice quality formation. The ethylene evolution rates and ACC concentrations in grains during the mid and late grain Filling stages were very significantly and positively correlated with chalky kernel percentage and chalkiness. The cultivars with a low ACC concentration in grains exhibited a close amyloplast arrangement and small space between starch granules, whereas those with a high ACC concentration in grains showed a loose arrangement and wide space between the granules. Application of 1 μmol/L ACC to panicles at mid and late grain Filling stages significantly loosened amyloplast arrangement and increased chalky kernel percentage, chalky area and chalkiness, and the results were reversed when 1 μmol/L amino-ethoxyvinylglycine, an inhibitor of ACC synthesis enzyme, was applied to panicles. A practice of moderate dry-wet alternate irrigation reduced ethylene evolution and ACC concentration in grains and thereby reduced chalkiness. The results suggested that ethylene and ACC in grains play an important role in the endosperm structure and appearance quality of rice, and the appearance quality would be improved by reducing ethylene evolution and ACC in grains through either variety breeding and selection, or chemical regulations or cultivation techniques
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grain Filling of cereals under soil drying
New Phytologist, 2006Co-Authors: Jianchang Yang, Jianhua ZhangAbstract:Contents Summary 223 I. Introduction 224 II. Problems in grain Filling: unfavorably delayed whole-plant senescence 224 III. Controlled soil drying improves carbon remobilization and grain Filling as a result of enhanced whole-plant senescence 225 IV. Hormonal regulation of whole-plant senescence and grain Filling 229 V. Activities of key enzymes involved in carbon remobilization and grain Filling 230 VI. Conclusions 232 Acknowledgements 232 References 232 Summary Monocarpic plants require the initiation of whole-plant senescence to remobilize and transfer assimilates pre-stored in vegetative tissues to grains. Delayed whole-plant senescence caused by either heavy use of nitrogen fertilizer or adoption of lodging-resistant cultivars/hybrids that remain green when the grains are due to ripen results in a low harvest index with much nonstructural carbohydrate (NSC) left in the straw. Usually, water stress during the grain-Filling Period induces early senescence, reduces photosynthesis, and shortens the grain-Filling Period; however, it increases the remobilization of NSC from the vegetative tissues to the grain. If mild soil drying is properly controlled during the later grain-Filling Period in rice (Oryza sativa) and wheat (Triticum aestivum), it can enhance whole-plant senescence, lead to faster and better remobilization of carbon from vegetative tissues to grains, and accelerate the grain-Filling rate. In cases where plant senescence is unfavorably delayed, such as by heavy use of nitrogen and the introduction of hybrids with strong heterosis, the gain from the enhanced remobilization and accelerated grain-Filling rate can outweigh the loss of reduced photosynthesis and the shortened grain-Filling Period, leading to an increased grain yield, better harvest index and higher water-use efficiency.
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grain Filling of cereals under soil drying
New Phytologist, 2006Co-Authors: Jianchang Yang, Jianhua ZhangAbstract:Monocarpic plants require the initiation of whole-plant senescence to remobilize and transfer assimilates pre-stored in vegetative tissues to grains. Delayed whole-plant senescence caused by either heavy use of nitrogen fertilizer or adoption of lodging-resistant cultivars/hybrids that remain green when the grains are due to ripen results in a low harvest index with much nonstructural carbohydrate (NSC) left in the straw. Usually, water stress during the grain-Filling Period induces early senescence, reduces photosynthesis, and shortens the grain-Filling Period; however, it increases the remobilization of NSC from the vegetative tissues to the grain. If mild soil drying is properly controlled during the later grain-Filling Period in rice (Oryza sativa) and wheat (Triticum aestivum), it can enhance whole-plant senescence, lead to faster and better remobilization of carbon from vegetative tissues to grains, and accelerate the grain-Filling rate. In cases where plant senescence is unfavorably delayed, such as by heavy use of nitrogen and the introduction of hybrids with strong heterosis, the gain from the enhanced remobilization and accelerated grain-Filling rate can outweigh the loss of reduced photosynthesis and the shortened grain-Filling Period, leading to an increased grain yield, better harvest index and higher water-use efficiency.
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activities of enzymes involved in sucrose to starch metabolism in rice grains subjected to water stress during Filling
Field Crops Research, 2003Co-Authors: Jianchang Yang, Jianhua Zhang, Qingsen Zhu, Zhiqin Wang, Lijun LiuAbstract:Abstract Slow grain Filling of rice (Oryza sativa L.) is a problem due to the heavy use of nitrogen fertilizer or the high lodging resistance of some cultivars. This study investigated if controlled water deficit during grain Filling could enhance sink strength by regulating key enzymes involved and lead to faster grain Filling. Two rice cultivars with high lodging resistance and slow grain Filling were grown in the field and treated with either normal nitrogen (NN) or high nitrogen (HN) at heading. Well-watered (WW) and water-deficit stressed (WS) treatments were imposed from 9 days after anthesis (DAA) until maturity. Leaf water potentials of both cultivars markedly decreased during the day as a result of WS treatments, but completely recovered by early morning. WS promoted the reallocation of prefixed 14 C from stems to grains, facilitated starch accumulation in grains and increased grain-Filling rate although it shortened grain-Filling Period. In contrast, HN behaved in the opposite way. Sucrose synthase (EC 2.4.1.13) activity was substantially enhanced by water stress, and was positively correlated with starch accumulation rate (SAR) in the grains. Both soluble and insoluble invertase (EC 3.2.1.26) activities were less enhanced by WS and showed no significant correlation with SAR. Starch branching enzyme (BE) (EC 2.4.1.18) and soluble starch synthase (EC 2.4.1.18) activities were also enhanced by the WS, with the former enhanced more than the latter, and were significantly correlated with SAR. Adenine diphosphoglucose pyrophosphorylase (EC 2.7.7.27) activity was little affected by WS. The results suggest that WS-increased remobilization and grain-Filling rate were attributed to enhanced sink strength by regulating sucrose synthase and starch BE activities in rice grains when subjected to water stress during the grain-Filling Period.
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remobilization of carbon reserves in response to water deficit during grain Filling of rice
Field Crops Research, 2001Co-Authors: Jianchang Yang, Jianhua Zhang, Zhiqing Wang, Qingsen Zhu, Wei WangAbstract:Abstract Delayed senescence in rice plants caused by heavy use of nitrogen results in much non-structural carbohydrate (NSC) left in the straw and leads to low harvest index. This study was designed to determine if a moderate water deficit imposed during grain-Filling could enhance plant senescence and thus, lead to more remobilization of NSC stored in vegetative tissues to grain. Two lodging-resistant rice cultivars, Wuyujing 3 (japonica) and Yangdao 4 (indica), which usually show delayed senescence, were grown in the field. Two levels of nitrogen, either normal (5 g N m−2, NN) or high amounts (10 g N m−2, HN) were applied at heading. Two levels of soil–water potential (ψsoil), well-watered (WW, ψsoil=0) and water deficit stressed (WS, ψsoil=−0.05 MPa), were imposed 9 days after anthesis (DAA) until maturity. Leaf water potential of both cultivars markedly decreased at mid-day under WS treatments but completely recovered by early morning. Chlorophyll (Chl) concentrations and photosynthetic rate (Pr) of the flag leaves declined faster under WS than under WW treatments, indicating that the water deficit enhanced senescence, while HN greatly delayed it. The reduction of NSC in the culm and sheath was substantially enhanced by the WS treatment, NSC remobilization being increased by 23.8–27.1% at NN and 19.6–36.7% at HN, respectively, compared to the WW treatment. The contribution of remobilized NSC to grain, partitioning of fed 14 C from the flag leaves into grain, and harvest index were all significantly increased by WS at either NN or HN. WS also shortened the grain-Filling Period by 2.9–5.5 days at NN and 5.7–7.4 days at HN, and increased grain-Filling rate at NH and NN by 0.18–0.29, and 0.31–0.37 mg per day per grain, respectively, when compared to WW treatments. The percentage of ripened grains, grain weight and grain yield under WS treatments were not significantly reduced at NN, but increased significantly at HN. Water applied to WS during the water-withholding Period was only 64–70% of that to WW treatments. We conclude that the early senescence induced by a moderate water deficit during grain-Filling Period can enhance the remobilization of stored assimilates and accelerate grain-Filling of rice. Such enhancement may improve grain yield in cases where plant senescence is unfavorably delayed by heavy use of nitrogen. This practice would also contribute to water-saving in rice production.
Jianhua Zhang - One of the best experts on this subject based on the ideXlab platform.
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grain Filling of cereals under soil drying
New Phytologist, 2006Co-Authors: Jianchang Yang, Jianhua ZhangAbstract:Contents Summary 223 I. Introduction 224 II. Problems in grain Filling: unfavorably delayed whole-plant senescence 224 III. Controlled soil drying improves carbon remobilization and grain Filling as a result of enhanced whole-plant senescence 225 IV. Hormonal regulation of whole-plant senescence and grain Filling 229 V. Activities of key enzymes involved in carbon remobilization and grain Filling 230 VI. Conclusions 232 Acknowledgements 232 References 232 Summary Monocarpic plants require the initiation of whole-plant senescence to remobilize and transfer assimilates pre-stored in vegetative tissues to grains. Delayed whole-plant senescence caused by either heavy use of nitrogen fertilizer or adoption of lodging-resistant cultivars/hybrids that remain green when the grains are due to ripen results in a low harvest index with much nonstructural carbohydrate (NSC) left in the straw. Usually, water stress during the grain-Filling Period induces early senescence, reduces photosynthesis, and shortens the grain-Filling Period; however, it increases the remobilization of NSC from the vegetative tissues to the grain. If mild soil drying is properly controlled during the later grain-Filling Period in rice (Oryza sativa) and wheat (Triticum aestivum), it can enhance whole-plant senescence, lead to faster and better remobilization of carbon from vegetative tissues to grains, and accelerate the grain-Filling rate. In cases where plant senescence is unfavorably delayed, such as by heavy use of nitrogen and the introduction of hybrids with strong heterosis, the gain from the enhanced remobilization and accelerated grain-Filling rate can outweigh the loss of reduced photosynthesis and the shortened grain-Filling Period, leading to an increased grain yield, better harvest index and higher water-use efficiency.
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grain Filling of cereals under soil drying
New Phytologist, 2006Co-Authors: Jianchang Yang, Jianhua ZhangAbstract:Monocarpic plants require the initiation of whole-plant senescence to remobilize and transfer assimilates pre-stored in vegetative tissues to grains. Delayed whole-plant senescence caused by either heavy use of nitrogen fertilizer or adoption of lodging-resistant cultivars/hybrids that remain green when the grains are due to ripen results in a low harvest index with much nonstructural carbohydrate (NSC) left in the straw. Usually, water stress during the grain-Filling Period induces early senescence, reduces photosynthesis, and shortens the grain-Filling Period; however, it increases the remobilization of NSC from the vegetative tissues to the grain. If mild soil drying is properly controlled during the later grain-Filling Period in rice (Oryza sativa) and wheat (Triticum aestivum), it can enhance whole-plant senescence, lead to faster and better remobilization of carbon from vegetative tissues to grains, and accelerate the grain-Filling rate. In cases where plant senescence is unfavorably delayed, such as by heavy use of nitrogen and the introduction of hybrids with strong heterosis, the gain from the enhanced remobilization and accelerated grain-Filling rate can outweigh the loss of reduced photosynthesis and the shortened grain-Filling Period, leading to an increased grain yield, better harvest index and higher water-use efficiency.
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activities of enzymes involved in sucrose to starch metabolism in rice grains subjected to water stress during Filling
Field Crops Research, 2003Co-Authors: Jianchang Yang, Jianhua Zhang, Qingsen Zhu, Zhiqin Wang, Lijun LiuAbstract:Abstract Slow grain Filling of rice (Oryza sativa L.) is a problem due to the heavy use of nitrogen fertilizer or the high lodging resistance of some cultivars. This study investigated if controlled water deficit during grain Filling could enhance sink strength by regulating key enzymes involved and lead to faster grain Filling. Two rice cultivars with high lodging resistance and slow grain Filling were grown in the field and treated with either normal nitrogen (NN) or high nitrogen (HN) at heading. Well-watered (WW) and water-deficit stressed (WS) treatments were imposed from 9 days after anthesis (DAA) until maturity. Leaf water potentials of both cultivars markedly decreased during the day as a result of WS treatments, but completely recovered by early morning. WS promoted the reallocation of prefixed 14 C from stems to grains, facilitated starch accumulation in grains and increased grain-Filling rate although it shortened grain-Filling Period. In contrast, HN behaved in the opposite way. Sucrose synthase (EC 2.4.1.13) activity was substantially enhanced by water stress, and was positively correlated with starch accumulation rate (SAR) in the grains. Both soluble and insoluble invertase (EC 3.2.1.26) activities were less enhanced by WS and showed no significant correlation with SAR. Starch branching enzyme (BE) (EC 2.4.1.18) and soluble starch synthase (EC 2.4.1.18) activities were also enhanced by the WS, with the former enhanced more than the latter, and were significantly correlated with SAR. Adenine diphosphoglucose pyrophosphorylase (EC 2.7.7.27) activity was little affected by WS. The results suggest that WS-increased remobilization and grain-Filling rate were attributed to enhanced sink strength by regulating sucrose synthase and starch BE activities in rice grains when subjected to water stress during the grain-Filling Period.
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remobilization of carbon reserves in response to water deficit during grain Filling of rice
Field Crops Research, 2001Co-Authors: Jianchang Yang, Jianhua Zhang, Zhiqing Wang, Qingsen Zhu, Wei WangAbstract:Abstract Delayed senescence in rice plants caused by heavy use of nitrogen results in much non-structural carbohydrate (NSC) left in the straw and leads to low harvest index. This study was designed to determine if a moderate water deficit imposed during grain-Filling could enhance plant senescence and thus, lead to more remobilization of NSC stored in vegetative tissues to grain. Two lodging-resistant rice cultivars, Wuyujing 3 (japonica) and Yangdao 4 (indica), which usually show delayed senescence, were grown in the field. Two levels of nitrogen, either normal (5 g N m−2, NN) or high amounts (10 g N m−2, HN) were applied at heading. Two levels of soil–water potential (ψsoil), well-watered (WW, ψsoil=0) and water deficit stressed (WS, ψsoil=−0.05 MPa), were imposed 9 days after anthesis (DAA) until maturity. Leaf water potential of both cultivars markedly decreased at mid-day under WS treatments but completely recovered by early morning. Chlorophyll (Chl) concentrations and photosynthetic rate (Pr) of the flag leaves declined faster under WS than under WW treatments, indicating that the water deficit enhanced senescence, while HN greatly delayed it. The reduction of NSC in the culm and sheath was substantially enhanced by the WS treatment, NSC remobilization being increased by 23.8–27.1% at NN and 19.6–36.7% at HN, respectively, compared to the WW treatment. The contribution of remobilized NSC to grain, partitioning of fed 14 C from the flag leaves into grain, and harvest index were all significantly increased by WS at either NN or HN. WS also shortened the grain-Filling Period by 2.9–5.5 days at NN and 5.7–7.4 days at HN, and increased grain-Filling rate at NH and NN by 0.18–0.29, and 0.31–0.37 mg per day per grain, respectively, when compared to WW treatments. The percentage of ripened grains, grain weight and grain yield under WS treatments were not significantly reduced at NN, but increased significantly at HN. Water applied to WS during the water-withholding Period was only 64–70% of that to WW treatments. We conclude that the early senescence induced by a moderate water deficit during grain-Filling Period can enhance the remobilization of stored assimilates and accelerate grain-Filling of rice. Such enhancement may improve grain yield in cases where plant senescence is unfavorably delayed by heavy use of nitrogen. This practice would also contribute to water-saving in rice production.
Lucas E Bonelli - One of the best experts on this subject based on the ideXlab platform.
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maize grain yield components and source sink relationship as affected by the delay in sowing date
Field Crops Research, 2016Co-Authors: Lucas E Bonelli, J P Monzon, Anibal Cerrudo, Roberto H Rizzalli, F H AndradeAbstract:Abstract Delaying maize ( Zea mays L.) sowing date can diminish grain yields through reductions in the number, size and activity of growing grains (sink strength) and/or reductions in the assimilate supply (source capacity) to grains during the grain Filling Period. Whether the source capacity or the sink strength is the limiting factor for grain yield in late sown maize still remains unclear. Understanding source-sink relationships is relevant to optimize crop management practices, to identify critical processes for crop modelling and to develop breeding strategies. The objective of this work was to assess the effect of delays in maize sowing date on grain yield components and on the source-sink relationship during the grain Filling Period. Three well irrigated and fertilized maize field experiments were conducted at Balcarce, Argentina (37° 45′ S, 58° 18′ W; 130 m a.s.l.) during 2009–10; 2010–11 and 2011–12 cropping seasons. Sowing dates ranged from October to January covering a broad range of the seasonal photo-thermal variation. Grain yield was affected by sowing date and varied from 1680 g m −2 (early sowings) to 203 g m −2 (late sowings). Grain number per unit area was reduced proportionally less than weight per grain as sowing date was delayed. Variations in grain yield were related to the harvest index, and were closely associated with dry matter accumulation during the post-silking Period. The variation of source capacity was higher than that of sink strength during the grain Filling Period and the source/sink ratio decreased from early to late sowing dates. Results indicate that crop growth during the grain Filling Period was limited by the sink strength in early sowing dates and by the photosynthetic source capacity in the late ones.
Woonho Yang - One of the best experts on this subject based on the ideXlab platform.
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relationship between grain Filling duration and leaf senescence of temperate rice under high temperature
Field Crops Research, 2011Co-Authors: Junwhan Kim, Jiyoung Shon, Chungkuen Lee, Woonho Yang, Youngwhan Yoon, Wonha Yang, Yuongyu Kim, Byunwoo LeeAbstract:Abstract High temperature during grain Filling Period has been reported to decrease the grain Filling duration, leading to the lower grain weight and yield of rice. Two experiments in the phytotron and field were carried out to test the hypothesis that the leaf senescence of rice plants may determine the grain Filling duration under high temperature. In the phytotron experiment in 2008, rice plants of a japonica cultivar “Ilpumbyeo” were subjected to three minimum/maximum (mean) temperature regimes of 11/19 (15), 17/25 (21), and 23/31 °C (27 °C). In the field experiment, rice seedlings of the same rice cultivar were transplanted on May 6th and June 19th in 2009 and the mean temperatures during the grain Filling Period were 24.4 and 21.9 °C, respectively. Both experiments revealed consistently that high temperature increased the rates of grain Filling and leaf senescence while it reduced the durations of them. However, grain Filling was terminated earlier than complete leaf senescence, the time gap being greater at higher temperature. In addition, the fraction of dry matter partitioning to the leaf sheath + culm resumed to increase following the termination of grain Filling under high temperature, indicating that leaves were still maintaining photosynthetic capacity and supplying assimilates into the other plant tissues except grain even after the termination of grain Filling. These findings suggest that an early termination of grain Filling in temperate rice under high temperature was not resulted from the lack of assimilate owing to the early leaf senescence but from the loss of sink activity owing to the earlier senescence of panicle.
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grain Filling duration a crucial determinant of genotypic variation of grain yield in field grown tropical irrigated rice
Field Crops Research, 2008Co-Authors: Woonho Yang, Shaobing Peng, Maribel L Dionisiosese, Rebecca C Laza, Romeo M VisperasAbstract:Abstract Grain Filling, a crucial determinant of grain yield in cereal crops, is characterized by duration and rate of grain Filling. This study aimed to (1) seek genotypic variations in grain Filling duration and rate on area basis, (2) compare the contribution of grain Filling duration and rate to grain yield and (3) examine the influence of temperature and solar radiation on grain Filling duration and rate for effective grain Filling Period in the field-grown tropical irrigated rice. Six tropical genotypes were used in the 2004 dry season and wet season at the International Rice Research Institute (IRRI), Laguna, Philippines. Grain Filling rate and duration exhibited highly significant genotypic variations in each crop season. Grain weight on area basis was positively associated with grain Filling duration, irrespective of crop seasons, but negatively or not significantly associated with grain Filling rate. Grain Filling rate and duration were negatively correlated with each other. Final grain weight linearly increased with the rise in cumulative mean temperature and cumulative solar radiation. Longer grain Filling duration resulted in higher cumulative mean temperature and cumulative solar radiation for effective grain Filling. Higher daily mean temperature and radiation did not accelerate daily grain Filling rates of different rice genotypes. It was concluded that longer grain Filling duration, which provided rice plants with more cumulative mean temperature and cumulative solar radiation for effective grain Filling Period, was the main factor that determined grain yield on unit area basis in the field-grown tropical irrigated rice genotypes.