Two wheat cultivars （Triticum aestivum L.） were used to evaluate the effects ofpost-anthesis severe water deficit （SD） on starch content and granule size distribution and their relations with ethylene and spermidi...Two wheat cultivars （Triticum aestivum L.） were used to evaluate the effects ofpost-anthesis severe water deficit （SD） on starch content and granule size distribution and their relations with ethylene and spermidine （Spd）. Comparison to the well-watered （WW） treatment, SD led to lower Spd and higher 1-aminocylopropane-l-carboxylic acid （ACC） concentrations and ethylene evolution rate （EER） in grains at the critical stage of forming starch granules. Application of Spd or aminoethoxyvinylglycine （AVG） significantly reduced ACC concentration and EER and increased Spd concentration, while ethephon or methylglyoxal-bis （MGBG） had an opposite impact. The volume and surface area distribution of starch granules showed a bimodal curve, while the number distribution exhibited a unimodal curve. SD caused a marked drop in grain weight, grain number and starch content, also led to a significant reduction in the proportion （both by volume and by surface area） of B-type starch granules （〈10 Ixm）, with an increase in those of A-type starch granules （〉10 ~tm）. Application of Spd or AVG increased the proportion （both by volume and by surface area） of B-type starch granules under SD. Correlation analysis suggested that ethylene and Spd showed an antagonism relation in the formation of B-type granules. These results suggested that it would be good for the formation of B-type starch granules to have the physiological traits of higher Spd and lower ACC concentrations and ethylene emission under SD.展开更多
A segregating population with 410 F2 individuals from the cross MERCIA （Rht-Bla）×Dwarf 123 was made to identify a new major dwarfing gene carrying by novel wheat germplasm Dwarf 123. Combination of bulk segeran...A segregating population with 410 F2 individuals from the cross MERCIA （Rht-Bla）×Dwarf 123 was made to identify a new major dwarfing gene carrying by novel wheat germplasm Dwarf 123. Combination of bulk segerant analysis method was used. A total of 145 SSR markers were tested for polymorphisms among parental lines and DNA bulks of F2 population. Out of 145 primer pairs only three markers revealed corresponding polymorphism among parental lines and F2 DNA bulks. The marker Barc20 was close to the dwarfing gene with a genetic distance of 1.8 cM, and markers Gwm513 and Gwm495 were linked to the gene with genetic distance of 6.7 and 13 cM, respectively. Linkage analysis mapped the dwarfing gene to the long arm of chromosome 4B with the order of Barc20-dwarfing gene-Gwm513-Gwm495. The Comparision between the new gene and the known Rht-B1 alleles showed that dwarfing gene Rht-Ai123 was different from the others. The identification of the new dwarfing gene and its linked markers will greatly facilitate its utilization in wheat high yield breeding for reducing plant height.展开更多
Drought is a major environmental stress limiting global wheat(Triticum aestivum)production.Exploring drought tolerance genes is important for improving drought adaptation in this crop.Here,we cloned and characterized ...Drought is a major environmental stress limiting global wheat(Triticum aestivum)production.Exploring drought tolerance genes is important for improving drought adaptation in this crop.Here,we cloned and characterized TaTIP41,a novel drought tolerance gene in wheat.TaTIP41 is a putative conserved component of target of rapamycin(TOR)signaling,and the Ta TIP41 homoeologs were expressed in response to drought stress and abscisic acid(ABA).The overexpression of Ta TIP41 enhanced drought tolerance and the ABA response,including ABA-induced stomatal closure,while its downregulation using RNA interference(RNAi)had the opposite effect.Furthermore,Ta TIP41 physically interacted with TaTAP46,another conserved component of TOR signaling.Like TaTIP41,TaTAP46 positively regulated drought tolerance.Furthermore,TaTIP41 and TaTAP46 interacted with type-2A protein phosphatase(PP2A)catalytic subunits,such as TaPP2A-2,and inhibited their enzymatic activities.Silencing TaPP2A-2 improved drought tolerance in wheat.Together,our findings provide new insights into the roles of TaTIP41 and TaTAP46 in the drought tolerance and ABA response in wheat,and their potential application in improving wheat environmental adaptability.展开更多
IN the late 1970s, biochemical analysis and electron microscopy of isolated, histone-depleted mitotic chromosomes demonstrated the existence of a central scaffold consisting mainly of nonhistone proteins (NHPs) in met...IN the late 1970s, biochemical analysis and electron microscopy of isolated, histone-depleted mitotic chromosomes demonstrated the existence of a central scaffold consisting mainly of nonhistone proteins (NHPs) in metaphase chromosomes. Subsequently, by using silver impregnation techniques and light microscopy, Howell et al. showed the presence of an axial chromatid core in relatively intact chromosomes of mammals; this core is believed to be展开更多
基金2013 Tangzhongying Plant Breeding ProjectFoundation for the Author of National Excellent Doctoral Dissertation of PR China(FANEDD 201176)+1 种基金The Project-sponsored by SRF for ROCS,SEM(2014)National Research Initiative Competitive Grants CAP project(2011-68002-30029)from the USDA National Institute of Food and Agriculture
基金the National Natural Science Foundation of China(31271661,30871477)the National Basic Research Program of China(2009CB118602)+1 种基金the Special Fund for Agro-Scientific Research in the Public Interest of China(201203100)the Key Technologies R&D Program of China during the 12th Five-Year Plan period(2012BAD04B05)
文摘Two wheat cultivars （Triticum aestivum L.） were used to evaluate the effects ofpost-anthesis severe water deficit （SD） on starch content and granule size distribution and their relations with ethylene and spermidine （Spd）. Comparison to the well-watered （WW） treatment, SD led to lower Spd and higher 1-aminocylopropane-l-carboxylic acid （ACC） concentrations and ethylene evolution rate （EER） in grains at the critical stage of forming starch granules. Application of Spd or aminoethoxyvinylglycine （AVG） significantly reduced ACC concentration and EER and increased Spd concentration, while ethephon or methylglyoxal-bis （MGBG） had an opposite impact. The volume and surface area distribution of starch granules showed a bimodal curve, while the number distribution exhibited a unimodal curve. SD caused a marked drop in grain weight, grain number and starch content, also led to a significant reduction in the proportion （both by volume and by surface area） of B-type starch granules （〈10 Ixm）, with an increase in those of A-type starch granules （〉10 ~tm）. Application of Spd or AVG increased the proportion （both by volume and by surface area） of B-type starch granules under SD. Correlation analysis suggested that ethylene and Spd showed an antagonism relation in the formation of B-type granules. These results suggested that it would be good for the formation of B-type starch granules to have the physiological traits of higher Spd and lower ACC concentrations and ethylene emission under SD.
基金supported by the Natural Science Foundation of Hebei Province,China (C200500637)the Key Technologies R&D Program of China during the 11th Five-Year Plan period (2006BAD13B02-08)the Hebei Provincial Science and Technology Underpinning Project,China (06820119D)
文摘A segregating population with 410 F2 individuals from the cross MERCIA （Rht-Bla）×Dwarf 123 was made to identify a new major dwarfing gene carrying by novel wheat germplasm Dwarf 123. Combination of bulk segerant analysis method was used. A total of 145 SSR markers were tested for polymorphisms among parental lines and DNA bulks of F2 population. Out of 145 primer pairs only three markers revealed corresponding polymorphism among parental lines and F2 DNA bulks. The marker Barc20 was close to the dwarfing gene with a genetic distance of 1.8 cM, and markers Gwm513 and Gwm495 were linked to the gene with genetic distance of 6.7 and 13 cM, respectively. Linkage analysis mapped the dwarfing gene to the long arm of chromosome 4B with the order of Barc20-dwarfing gene-Gwm513-Gwm495. The Comparision between the new gene and the known Rht-B1 alleles showed that dwarfing gene Rht-Ai123 was different from the others. The identification of the new dwarfing gene and its linked markers will greatly facilitate its utilization in wheat high yield breeding for reducing plant height.
基金国家重点基础研究计划(973计划)项目(2014CB138100)陕西省自然科学基金项目(2015JM3094)+3 种基金陕西省重点科技创新团队项目(2014KCT-25)资助supported by the National Key Basic Research Program of China(2014CB138100)the Natural Science Foundation of Shaanxi Province(2015JM3094)the Key Scientific and Technological Innovation Team of Shaanxi Province(2014KCT-25)
基金financialy supported by the National Key Research and Development Program of China(2022YFF1003402)the National Natural Science Foundation of China(32172045)+1 种基金the National Animal and Plant Transgenic Project(2016ZX08009001)the Natural Science Foundation of Ningxia Province(2022AAC02056)。
文摘Drought is a major environmental stress limiting global wheat(Triticum aestivum)production.Exploring drought tolerance genes is important for improving drought adaptation in this crop.Here,we cloned and characterized TaTIP41,a novel drought tolerance gene in wheat.TaTIP41 is a putative conserved component of target of rapamycin(TOR)signaling,and the Ta TIP41 homoeologs were expressed in response to drought stress and abscisic acid(ABA).The overexpression of Ta TIP41 enhanced drought tolerance and the ABA response,including ABA-induced stomatal closure,while its downregulation using RNA interference(RNAi)had the opposite effect.Furthermore,Ta TIP41 physically interacted with TaTAP46,another conserved component of TOR signaling.Like TaTIP41,TaTAP46 positively regulated drought tolerance.Furthermore,TaTIP41 and TaTAP46 interacted with type-2A protein phosphatase(PP2A)catalytic subunits,such as TaPP2A-2,and inhibited their enzymatic activities.Silencing TaPP2A-2 improved drought tolerance in wheat.Together,our findings provide new insights into the roles of TaTIP41 and TaTAP46 in the drought tolerance and ABA response in wheat,and their potential application in improving wheat environmental adaptability.
文摘IN the late 1970s, biochemical analysis and electron microscopy of isolated, histone-depleted mitotic chromosomes demonstrated the existence of a central scaffold consisting mainly of nonhistone proteins (NHPs) in metaphase chromosomes. Subsequently, by using silver impregnation techniques and light microscopy, Howell et al. showed the presence of an axial chromatid core in relatively intact chromosomes of mammals; this core is believed to be
