Ear differentiation,grain development and their interaction with factors in the growing environment,such as temperature,solar radiation and precipitation,greatly influence grain number and grain weight,and ultimately ...Ear differentiation,grain development and their interaction with factors in the growing environment,such as temperature,solar radiation and precipitation,greatly influence grain number and grain weight,and ultimately affect summer maize production.In this study,field experiments involving different sowing dates were conducted over three years to evaluate the effects of temperature factors,average solar radiation and total precipitation on the growth process,ear differentiation,fertilization characteristics,grain filling and yield of summer maize varieties with different growth durations.Four hybrids were evaluated in Huang-Huai-Hai Plain(HHHP),China from 2018 to 2020 with five different sowing dates.The results showed that the grain yield formation of summer maize was strongly impacted by the environment from the silking(R1)to milking(R3)stage.Average minimum temperature(AT_(min))was the key environmental factor that determined yield.Reductions in the length of the growing season(r=–0.556,P<0.01)and the total floret number on ear(R^(2)=0.200,P<0.001)were found when AT_(min) was elevated from the emerging(VE)to R1 stage.Both grain-filling rate(R^(2)=0.520,P<0.001)and the floret abortion rate on ear(R^(2)=0.437,P<0.001)showed quadratic relationships with AT_(min) from the R1 to physiological maturity(R6)stage,while the number of days after the R1 stage(r=–0.756,P<0.01)was negatively correlated with AT_(min).An increase in AT_(min) was beneficial for the promotion of yield when it did not exceeded a certain level(above 23°C during the R1–R3 stage and 20–21°C during the R1-R6 stage).Enhanced solar radiation and precipitation during R1–R6 increased the grain-filling rate(R^(2)=0.562,P<0.001 and R^(2)=0.229,P<0.05,respectively).Compared with short-season hybrids,full-season hybrids showed much greater suitability for a critical environment.The coordinated regulation of AT_(min),ear differentiation and grain development at the pre-and post-silking stages improved maize yield by increasing total floret number and grain-filling rate,and by reducing the floret abortion rate on ear.展开更多
We used a widely targeted metabolomics approach to examine the metabolic changes in three pedigreed indica cultivars(Meixiangzhan 2,Meisizhan and Qixinzhan),with different eating qualities,at 8,15 and 30 d after flowe...We used a widely targeted metabolomics approach to examine the metabolic changes in three pedigreed indica cultivars(Meixiangzhan 2,Meisizhan and Qixinzhan),with different eating qualities,at 8,15 and 30 d after flowering(DAF)to explore the formation mechanism of rice eating and nutritional qualities at a global metabolic level.A total of 623 metabolites were identified,and results showed that metabolic variations among rice cultivars decreased with grain developmental stage,suggesting that sufficient carbohydrate and amino acid supply during grain development may contribute to excellent rice eating and nutritional quality formation.Lysophosphatidylcholines 19:0 and 16:1 were beneficial for excellent eating quality formation during grain development.Rice fragrance was attributed mainly to spermidine andγ-aminobutyric acid.Rice cultivars with excellent eating quality at 15-30 DAF had relatively higher flavone content,possibly because they had adequate carbohydrate and amino acid contents during grain development.These results provided insight into the mechanisms for establishing rice eating and nutritional qualities during grain formation at a global metabolic level,and can be applied towards improving rice quality.展开更多
Inferior grains exhibit delayed developmental processes and reduced metabolic activities compared to superior grains,leading to unstable rice yield and quality.While significant advancements have been achieved in eluc...Inferior grains exhibit delayed developmental processes and reduced metabolic activities compared to superior grains,leading to unstable rice yield and quality.While significant advancements have been achieved in elucidating the physiology of endosperm filling in inferior grains,the role of the embryo remains underexplored and warrants comprehensive investigation.Two Wuyujing 3 mutants,DW024(relatively synchronous;syn-DW024)and DW179(significantly asynchronous;asyn-DW179),with different grain-filling patterns were used in this study.Samples of superior and inferior grains were collected at intervals from 5 to 60 d after fertilization and subsequently dissected into subsamples of the embryo and endosperm.Histochemical staining,biochemical analysis,and RNA sequencing(RNA-seq)were combined to systematically compare developmental and physiological traits between superior and inferior grains.Combining hierarchical clustering of mRNA datasets revealed three developmental phases of the endosperm and embryo:morphogenesis,endosperm filling/embryo enlargement,and maturation.In both syn-DW024 and asyn-DW179,the duration of the endosperm/embryo morphogenesis phase was identical in superior and inferior grains.The inferior grains of asyn-DW179 exhibited a 10-day prolongation in the endosperm filling phase and a 20-day extension in the embryo enlargement phase compared to the superior grains.The endosperm of inferior grains exhibited higher contents of sugars and free amino acids,along with slower accumulation of storage compounds,which was associated with the down-regulation of genes for starch synthesis and ABA signaling.In addition,transporters for nutrient exchanges between endosperm and embryo were down-regulated,suggesting a potential role of the embryo in adjusting the endosperm filling process.Collectively,our results reveal that the prolonged phases of endosperm filling and embryo enlargement may underlie the impaired development of inferior grains,offering a new perspective for breeding or cultivating rice with uniform grain quality.展开更多
Development of wheat(Triticum aestivum L.)grain mainly depends on the processes of starch synthesis and storage protein accumulation,which are critical for grain yield and quality.However,the regulatory network underl...Development of wheat(Triticum aestivum L.)grain mainly depends on the processes of starch synthesis and storage protein accumulation,which are critical for grain yield and quality.However,the regulatory network underlying the transcriptional and physiological changes of grain development is still not clear.Here,we combined ATAC-seq and RNA-seq to discover the chromatin accessibility and gene expression dynamics during these processes.We found that the chromatin accessibility changes are tightly associated with differential transcriptomic expressions,and the proportion of distal ACRs was increased gradually during grain development.Specific transcription factor(TF)binding sites were enriched at different stages and were diversified among the 3 subgenomes.We further predicted the potential interactions between key TFs and genes related with starch and storage protein biosynthesis and found different copies of some key TFs played diversified roles.Overall,our findings have provided numerous resources and illustrated the regulatory network during wheat grain development,which would shed light on the improvement of wheat yields and qualities.展开更多
Although scientists have performed many studies on crescent （barchan） dunes in the Taklimakan Desert,few studies reported the changes in grain size at different development stages of crescent dunes.In order to evalu...Although scientists have performed many studies on crescent （barchan） dunes in the Taklimakan Desert,few studies reported the changes in grain size at different development stages of crescent dunes.In order to evaluate the changing trends of surface sediment grain size with dune development,we investigated the grain size characteristics at four developmental stages （oval sand pile,shield dune,incipient crescent dune and mature crescent dune） of crescent dunes by measuring the morphology of sand dune and observing the near-surface wind regime.The dunes have developed in a wide inter-dune corridor between high compound longitudinal ridges in China＇s Taklimakan Desert.The surface sediments at four developmental stages of the crescent dunes were primarily composed of fine sands,followed by very fine and medium sands.Mean grain sizes ranged from 2.8 to 3.1 φ,with a unimodal distribution.The sands were moderately well-sorted,their distribution varied from platykurtic to very platykurtic,and symmetrical or skewed towards the fine particles.From oval sand piles through shield and incipient crescent dunes to mature crescent dunes,incipient grain size gradually increased,particles became finer,sorting became better,kurtosis and skewness increased.Grain sizes on the surface layer became coarser upwards from the toe of the windward slope and then became finer towards the bottom of the leeward slope.We found that the coarsest particles at different positions at the four developmental stages were different.The coarsest particles were distributed at the top of the oval sand piles and shield dunes,versus at the middle of the windward slope of the incipient and mature crescent dunes.Correlations between the mean grain size and other grain size parameters showed that as mean grain size became finer,sorting became better and kurtosis became wider,but skewness changed only slightly.In addition,grain size variation in the surface sediments correlated with the movement speed of the dunes in the study area.In the open ground among tall-complex longitudinal ridges in the hinterland of the Taklimakan Desert where aeolian environment is characterized by comparatively strong wind and unsaturated sand flow,faster dune movement corresponded to coarser grain size.展开更多
Agriculture is the foundation of the national economy,while grain is the cornet stone of that foundation.It is also essential for subsistence and development of the mankind. In recent years,especially since its entry ...Agriculture is the foundation of the national economy,while grain is the cornet stone of that foundation.It is also essential for subsistence and development of the mankind. In recent years,especially since its entry into the WTO, China has been undergoing a period of twists and turns in the development of its grain production and trade which used to be sound and stable.展开更多
Haynaldia villosa(2n=14,VV),a wild grass of the subtribe Triticeae,serves as potential gene resources for wheat genetic improvement.In this study,the proteome characterization during grain development of Yangmai 5 and...Haynaldia villosa(2n=14,VV),a wild grass of the subtribe Triticeae,serves as potential gene resources for wheat genetic improvement.In this study,the proteome characterization during grain development of Yangmai 5 and Yangmai 5-H.villosa 6VS/6AL translocation line was investigated by a comparative proteomic approach.Two-dimensional electrophoresis identified 81 differentially accumulated proteins(DAPs)during five grain developmental stages in wheat-H.villosa translocation line.These proteins were mainly involved in stress defense,storage protein,energy metabolism,protein metabolism and folding,carbon metabolism,nitrogen metabolism,and starch metabolism.In particular,6VS/6AL translocation led to significant upregulation of 36 DAPs and specific expression of 11 DAPs such as chitinase,thaumatin-like proteins,glutathione transferase,α-amylase inhibitor,heat shock proteins,and betaine aldehyde dehydrogenase.These proteins mainly involved in biotic and abiotic stress responses.Further analysis found that the upstream 1500 promoter regions of these stress-responsive DAP genes contained multiple high-frequency cis-acting elements related to stress defense such as abscisic acid response element ABRE,methyl jasmonate(MeJA)-response element TGACG-motif and CGTCA-motif involved in oxidative stress and antioxidant response element(ARE).RNA-seq and RT-qPCR analyses revealed the high expression of these stress-defensive DAP genes in the developing grains,particularly at the early-middle grain filling stages.Our results demonstrated that 6VS chromosome of H.villosa contains abundant stress-defensive proteins that have potential values for wheat genetic improvement.展开更多
Enhancing crop productivity and quality remains a paramount breeding objective to address the dual challenges of global population growth and escalating demand.Cereal endosperms,particularly in staple crops such as ri...Enhancing crop productivity and quality remains a paramount breeding objective to address the dual challenges of global population growth and escalating demand.Cereal endosperms,particularly in staple crops such as rice,wheat,and maize,constitute the world's primary source of human nutrition and animal feed.展开更多
The purpose of this study is to reveal the effects of historic climate change on rice yield over the middle and lower reaches of the Yangtze River, China, and to better adapt to climate change in the future. This stud...The purpose of this study is to reveal the effects of historic climate change on rice yield over the middle and lower reaches of the Yangtze River, China, and to better adapt to climate change in the future. This study presents the relation of temperature and precipitation and rice components from 1981 to 2003 at 48 early rice stations and 30 middle rice stations. It focuses on an analysis of three stages： flowering, pre-milk, and late milk. The results show that mean maximum temperature and mean daily precipitation at the stages of flowering and pre-milk are most related to early rice yield. Yield change of middle rice is mainly because of mean precipitation change at the flowering stage. Furthermore, percentage of undeveloped grain increases as mean maximum temperature rises at the flowering stage. Over-precipitation in the reproductive stage is a major reason for reduction in yield of early rice. Consecutive rainfall and continuous high temperature can have negative effects on middle rice yield. Global warming would affect middle rice more seriously than early rice.展开更多
Many studies have reported that polyamines have an effect on a number of growth and developmental process in plants, such as cell division, embryogenesis, senescense, and flowering. However, there are few reports on t...Many studies have reported that polyamines have an effect on a number of growth and developmental process in plants, such as cell division, embryogenesis, senescense, and flowering. However, there are few reports on the physiological significance in of polyamines grain filling of rice. We studied the level of polyamines in the developing grains and their relations with grain filling and grain weight, using 8 rice varieties including hybrid combinations. It was showed that the content of Put (puterscine), Spd (spermidine), and Spm (spermine), especially Spd and Spm, was展开更多
Both the filling and development of grain are key processes determining agriculture production and reproductive growth in rice.The processes of grain filling and endosperm development are crucial for the accumulation ...Both the filling and development of grain are key processes determining agriculture production and reproductive growth in rice.The processes of grain filling and endosperm development are crucial for the accumulation of major storage compounds in rice grains.This requires extensive remobilization of carbon reserves from source to sink and the precise regulation of sucrose-to-starch conversion.Both the developmental sequence of the panicle and environmental signals influence the carbon flow between the leaves,leaf sheath,stem,and spikelets during grain filling.This,in turn,affects endosperm development and the production of storage compounds.In this review,we synthesize recent insight into grain development in rice,focusing on the dynamic changes in phytohormones and how their homeostasis integrates developmental and environmental cues to control grain filling in the developing panicle.We also highlight recent advances in the genetic control of carbohydrate remobilization and the transcriptional regulatory networks governing carbohydrate metabolism and grain development in rice.The asynchronous initiation and imbalance in grain filling limit the full yield potential of cereal crops.The“superior/inferior spikelets”serve as a model system for understanding the regulatory mechanisms underlying grain filling and development.Systematic research on carbohydrate flow and phytohormone crosstalk could enhance our understanding of optimizing yield production in cereal crops.Additionally,a thorough analysis of key genetic regulatory mechanisms can offer a genetic foundation and targets for precisely adjusting grain filling traits,ultimately aiding in the development of high-yield crop varieties.展开更多
基金supported by Key Technology Research and Development Program of Shandong Province,China(2021LZGC014-2)the National Natural Science Foundation of China(32172115)the National Modern Agriculture Industry Technology System,China(CARS02-21)。
文摘Ear differentiation,grain development and their interaction with factors in the growing environment,such as temperature,solar radiation and precipitation,greatly influence grain number and grain weight,and ultimately affect summer maize production.In this study,field experiments involving different sowing dates were conducted over three years to evaluate the effects of temperature factors,average solar radiation and total precipitation on the growth process,ear differentiation,fertilization characteristics,grain filling and yield of summer maize varieties with different growth durations.Four hybrids were evaluated in Huang-Huai-Hai Plain(HHHP),China from 2018 to 2020 with five different sowing dates.The results showed that the grain yield formation of summer maize was strongly impacted by the environment from the silking(R1)to milking(R3)stage.Average minimum temperature(AT_(min))was the key environmental factor that determined yield.Reductions in the length of the growing season(r=–0.556,P<0.01)and the total floret number on ear(R^(2)=0.200,P<0.001)were found when AT_(min) was elevated from the emerging(VE)to R1 stage.Both grain-filling rate(R^(2)=0.520,P<0.001)and the floret abortion rate on ear(R^(2)=0.437,P<0.001)showed quadratic relationships with AT_(min) from the R1 to physiological maturity(R6)stage,while the number of days after the R1 stage(r=–0.756,P<0.01)was negatively correlated with AT_(min).An increase in AT_(min) was beneficial for the promotion of yield when it did not exceeded a certain level(above 23°C during the R1–R3 stage and 20–21°C during the R1-R6 stage).Enhanced solar radiation and precipitation during R1–R6 increased the grain-filling rate(R^(2)=0.562,P<0.001 and R^(2)=0.229,P<0.05,respectively).Compared with short-season hybrids,full-season hybrids showed much greater suitability for a critical environment.The coordinated regulation of AT_(min),ear differentiation and grain development at the pre-and post-silking stages improved maize yield by increasing total floret number and grain-filling rate,and by reducing the floret abortion rate on ear.
基金This study was supported by the Natural Science Foundation of Guangdong Province of China(Grant Nos.2018A030313465 and 2015B020231001)the National High-Tech Research and Development Program of China(Grant No.2014AA10A604-19)+1 种基金the National Natural Science Foundation of China(Grant No.31801448)the Special Fund for Scientific Innovation Strategy-Construction of High Level Academy of Agriculture Science(Grant No.R2018PY-QF003).
文摘We used a widely targeted metabolomics approach to examine the metabolic changes in three pedigreed indica cultivars(Meixiangzhan 2,Meisizhan and Qixinzhan),with different eating qualities,at 8,15 and 30 d after flowering(DAF)to explore the formation mechanism of rice eating and nutritional qualities at a global metabolic level.A total of 623 metabolites were identified,and results showed that metabolic variations among rice cultivars decreased with grain developmental stage,suggesting that sufficient carbohydrate and amino acid supply during grain development may contribute to excellent rice eating and nutritional quality formation.Lysophosphatidylcholines 19:0 and 16:1 were beneficial for excellent eating quality formation during grain development.Rice fragrance was attributed mainly to spermidine andγ-aminobutyric acid.Rice cultivars with excellent eating quality at 15-30 DAF had relatively higher flavone content,possibly because they had adequate carbohydrate and amino acid contents during grain development.These results provided insight into the mechanisms for establishing rice eating and nutritional qualities during grain formation at a global metabolic level,and can be applied towards improving rice quality.
基金supported by the National Key Research and Development Program of China(2022YFD2300700)the National Natural Science Foundation of China(32201894)+1 种基金Hainan Provincial Natural Science Foundation of China(323QN193)Rothamsted Research receives strategic funding from the Biotechnological and Biological Sciences Research Council of the UK.Matthew J.Paul acknowledges funding from the Delivering Sustainable Wheat(BB/X011003/1)Strategic Program.
文摘Inferior grains exhibit delayed developmental processes and reduced metabolic activities compared to superior grains,leading to unstable rice yield and quality.While significant advancements have been achieved in elucidating the physiology of endosperm filling in inferior grains,the role of the embryo remains underexplored and warrants comprehensive investigation.Two Wuyujing 3 mutants,DW024(relatively synchronous;syn-DW024)and DW179(significantly asynchronous;asyn-DW179),with different grain-filling patterns were used in this study.Samples of superior and inferior grains were collected at intervals from 5 to 60 d after fertilization and subsequently dissected into subsamples of the embryo and endosperm.Histochemical staining,biochemical analysis,and RNA sequencing(RNA-seq)were combined to systematically compare developmental and physiological traits between superior and inferior grains.Combining hierarchical clustering of mRNA datasets revealed three developmental phases of the endosperm and embryo:morphogenesis,endosperm filling/embryo enlargement,and maturation.In both syn-DW024 and asyn-DW179,the duration of the endosperm/embryo morphogenesis phase was identical in superior and inferior grains.The inferior grains of asyn-DW179 exhibited a 10-day prolongation in the endosperm filling phase and a 20-day extension in the embryo enlargement phase compared to the superior grains.The endosperm of inferior grains exhibited higher contents of sugars and free amino acids,along with slower accumulation of storage compounds,which was associated with the down-regulation of genes for starch synthesis and ABA signaling.In addition,transporters for nutrient exchanges between endosperm and embryo were down-regulated,suggesting a potential role of the embryo in adjusting the endosperm filling process.Collectively,our results reveal that the prolonged phases of endosperm filling and embryo enlargement may underlie the impaired development of inferior grains,offering a new perspective for breeding or cultivating rice with uniform grain quality.
基金This project was financially supported by the Outstanding Young Scientist Foundation of NSFC(Overseas)the Central Public-interest Scientific Institution Basic Research Found(S2022ZD02)+1 种基金the Fundamental Research Funds from Institute of Crop Sciences,Chinese Academy of Agricultural Sciences(S2020YC07 and S2021YC03)CAAS Agricultural Science and Technology Innovation Program,China(CAAS-ZDRW202002).
文摘Development of wheat(Triticum aestivum L.)grain mainly depends on the processes of starch synthesis and storage protein accumulation,which are critical for grain yield and quality.However,the regulatory network underlying the transcriptional and physiological changes of grain development is still not clear.Here,we combined ATAC-seq and RNA-seq to discover the chromatin accessibility and gene expression dynamics during these processes.We found that the chromatin accessibility changes are tightly associated with differential transcriptomic expressions,and the proportion of distal ACRs was increased gradually during grain development.Specific transcription factor(TF)binding sites were enriched at different stages and were diversified among the 3 subgenomes.We further predicted the potential interactions between key TFs and genes related with starch and storage protein biosynthesis and found different copies of some key TFs played diversified roles.Overall,our findings have provided numerous resources and illustrated the regulatory network during wheat grain development,which would shed light on the improvement of wheat yields and qualities.
基金supported by the National Natural Science Foundation of China (41571011,41330746)
文摘Although scientists have performed many studies on crescent （barchan） dunes in the Taklimakan Desert,few studies reported the changes in grain size at different development stages of crescent dunes.In order to evaluate the changing trends of surface sediment grain size with dune development,we investigated the grain size characteristics at four developmental stages （oval sand pile,shield dune,incipient crescent dune and mature crescent dune） of crescent dunes by measuring the morphology of sand dune and observing the near-surface wind regime.The dunes have developed in a wide inter-dune corridor between high compound longitudinal ridges in China＇s Taklimakan Desert.The surface sediments at four developmental stages of the crescent dunes were primarily composed of fine sands,followed by very fine and medium sands.Mean grain sizes ranged from 2.8 to 3.1 φ,with a unimodal distribution.The sands were moderately well-sorted,their distribution varied from platykurtic to very platykurtic,and symmetrical or skewed towards the fine particles.From oval sand piles through shield and incipient crescent dunes to mature crescent dunes,incipient grain size gradually increased,particles became finer,sorting became better,kurtosis and skewness increased.Grain sizes on the surface layer became coarser upwards from the toe of the windward slope and then became finer towards the bottom of the leeward slope.We found that the coarsest particles at different positions at the four developmental stages were different.The coarsest particles were distributed at the top of the oval sand piles and shield dunes,versus at the middle of the windward slope of the incipient and mature crescent dunes.Correlations between the mean grain size and other grain size parameters showed that as mean grain size became finer,sorting became better and kurtosis became wider,but skewness changed only slightly.In addition,grain size variation in the surface sediments correlated with the movement speed of the dunes in the study area.In the open ground among tall-complex longitudinal ridges in the hinterland of the Taklimakan Desert where aeolian environment is characterized by comparatively strong wind and unsaturated sand flow,faster dune movement corresponded to coarser grain size.
文摘Agriculture is the foundation of the national economy,while grain is the cornet stone of that foundation.It is also essential for subsistence and development of the mankind. In recent years,especially since its entry into the WTO, China has been undergoing a period of twists and turns in the development of its grain production and trade which used to be sound and stable.
基金This research was financially supported by the National Key R&D Program of China(2016YFD0100502)the National Natural Science Foundation of China(31771773)。
文摘Haynaldia villosa(2n=14,VV),a wild grass of the subtribe Triticeae,serves as potential gene resources for wheat genetic improvement.In this study,the proteome characterization during grain development of Yangmai 5 and Yangmai 5-H.villosa 6VS/6AL translocation line was investigated by a comparative proteomic approach.Two-dimensional electrophoresis identified 81 differentially accumulated proteins(DAPs)during five grain developmental stages in wheat-H.villosa translocation line.These proteins were mainly involved in stress defense,storage protein,energy metabolism,protein metabolism and folding,carbon metabolism,nitrogen metabolism,and starch metabolism.In particular,6VS/6AL translocation led to significant upregulation of 36 DAPs and specific expression of 11 DAPs such as chitinase,thaumatin-like proteins,glutathione transferase,α-amylase inhibitor,heat shock proteins,and betaine aldehyde dehydrogenase.These proteins mainly involved in biotic and abiotic stress responses.Further analysis found that the upstream 1500 promoter regions of these stress-responsive DAP genes contained multiple high-frequency cis-acting elements related to stress defense such as abscisic acid response element ABRE,methyl jasmonate(MeJA)-response element TGACG-motif and CGTCA-motif involved in oxidative stress and antioxidant response element(ARE).RNA-seq and RT-qPCR analyses revealed the high expression of these stress-defensive DAP genes in the developing grains,particularly at the early-middle grain filling stages.Our results demonstrated that 6VS chromosome of H.villosa contains abundant stress-defensive proteins that have potential values for wheat genetic improvement.
基金supported by the Biological Breeding-National Science and Technology Major Project(2023ZD04069)the National Natural Science Foundation of China(32230074 and 32470264)。
文摘Enhancing crop productivity and quality remains a paramount breeding objective to address the dual challenges of global population growth and escalating demand.Cereal endosperms,particularly in staple crops such as rice,wheat,and maize,constitute the world's primary source of human nutrition and animal feed.
文摘The purpose of this study is to reveal the effects of historic climate change on rice yield over the middle and lower reaches of the Yangtze River, China, and to better adapt to climate change in the future. This study presents the relation of temperature and precipitation and rice components from 1981 to 2003 at 48 early rice stations and 30 middle rice stations. It focuses on an analysis of three stages： flowering, pre-milk, and late milk. The results show that mean maximum temperature and mean daily precipitation at the stages of flowering and pre-milk are most related to early rice yield. Yield change of middle rice is mainly because of mean precipitation change at the flowering stage. Furthermore, percentage of undeveloped grain increases as mean maximum temperature rises at the flowering stage. Over-precipitation in the reproductive stage is a major reason for reduction in yield of early rice. Consecutive rainfall and continuous high temperature can have negative effects on middle rice yield. Global warming would affect middle rice more seriously than early rice.
文摘Many studies have reported that polyamines have an effect on a number of growth and developmental process in plants, such as cell division, embryogenesis, senescense, and flowering. However, there are few reports on the physiological significance in of polyamines grain filling of rice. We studied the level of polyamines in the developing grains and their relations with grain filling and grain weight, using 8 rice varieties including hybrid combinations. It was showed that the content of Put (puterscine), Spd (spermidine), and Spm (spermine), especially Spd and Spm, was
基金National Natural Science Foundation of China(32301739,32171927)the General Research Fund(12105824,12103220,12101722)+1 种基金The science and technology innovation Program of Hunan Province(2024RC3182)the Natural Science Foundation of Hunan Province(2025JJ70111).
文摘Both the filling and development of grain are key processes determining agriculture production and reproductive growth in rice.The processes of grain filling and endosperm development are crucial for the accumulation of major storage compounds in rice grains.This requires extensive remobilization of carbon reserves from source to sink and the precise regulation of sucrose-to-starch conversion.Both the developmental sequence of the panicle and environmental signals influence the carbon flow between the leaves,leaf sheath,stem,and spikelets during grain filling.This,in turn,affects endosperm development and the production of storage compounds.In this review,we synthesize recent insight into grain development in rice,focusing on the dynamic changes in phytohormones and how their homeostasis integrates developmental and environmental cues to control grain filling in the developing panicle.We also highlight recent advances in the genetic control of carbohydrate remobilization and the transcriptional regulatory networks governing carbohydrate metabolism and grain development in rice.The asynchronous initiation and imbalance in grain filling limit the full yield potential of cereal crops.The“superior/inferior spikelets”serve as a model system for understanding the regulatory mechanisms underlying grain filling and development.Systematic research on carbohydrate flow and phytohormone crosstalk could enhance our understanding of optimizing yield production in cereal crops.Additionally,a thorough analysis of key genetic regulatory mechanisms can offer a genetic foundation and targets for precisely adjusting grain filling traits,ultimately aiding in the development of high-yield crop varieties.
