Increasing the yield is one of the most important goals of crop improvement.Since the beginning of rice cultivation thousands of years ago,many efforts have been made to increase rice yield.One of the successes in thi...Increasing the yield is one of the most important goals of crop improvement.Since the beginning of rice cultivation thousands of years ago,many efforts have been made to increase rice yield.One of the successes in this history was the Green Revolution.This tremendous improvement in the 1960s was achieved by increasing rice and wheat production through the development and widespread adoption of semi-dwarf varieties with the extensive use of fertilizers(Hedden,2003).Dwarfism in crops lowers the center of gravity of the plant body,reducing the risk of lodging and enabling farmers to use more fertilizer to increase yields.Semi-dwarf mutations in both rice and wheat created during the Green Revolution are related to the plant growth hormone gibberellin(GA).Although other mechanisms cause dwarf mutants,only GA-related semi-dwarf mutants were selected during the Green Revolution(Wang et al.,2021).While GA-related abnormalities only make plants shorter,most cases caused by other mechanisms involve not only dwarfism but also other morphological abnormalities.展开更多
Improving grain quality is a primary objective in contemporary rice breeding.Japanese modern rice breeding has developed two different types of rice,eating and sake-brewing rice,with different grain characteristics,in...Improving grain quality is a primary objective in contemporary rice breeding.Japanese modern rice breeding has developed two different types of rice,eating and sake-brewing rice,with different grain characteristics,indicating the selection of variant gene alleles during the breeding process.Given the critical importance of promptly and efficiently identifying genes selected in past breeding for future molecular breeding,we conducted genome scans for divergence,genome-wide association studies,and map-based cloning.Consequently,we successfully identified two genes,OsMnS and OsWOX9D,both contributing to rice grain traits.OsMnS encodes a mannan synthase that increases the white core frequency in the endosperm,a desirable trait for sake brewing but decreases the grain appearance quality.OsWOX9D encodes a grass-specific homeobox-containing transcription factor,which enhances grain width for better sake brewing.Furthermore,haplotype analysis revealed that their defective alleles were selected in East Asia,but not Europe,during modern improvement.In addition,our analyses indicate that a reduction in grain mannan content during African rice domestication may also be caused a defective OsMnS allele due to breeding selection.This study not only reveals the delicate balance between grain appearance quality and nutrition in rice but also provides a new strategy for isolating causal genes underlying complex traits,based on the concept of“breeding-assisted genomics”in plants.展开更多
基金supported by JSPS KAKENHI grants 21K15120 and 24K01886(to H.Y.)and 22H02294(to M.M.)from the Ministry of Education,Culture,Sports,Science and Technology of Japanby the Cross-ministerial Moonshot Agriculture,Forestry and Fisheries Research and Development Program"Technologies for Smart Bio-industry and Agriculture"(funding agency:Bio-oriented Technology Research Advancement Institution)grant JPJ009237(to H.Y.)from the Cabinet Office,Government of Japan+1 种基金by the Priority Research Project(foR-F)of Fukushima University(262Q001 to H.Y.and M.M.)by the commissioned research fund provided by F-REI(JPFR23030101 to H.Y.and M.M.).
文摘Increasing the yield is one of the most important goals of crop improvement.Since the beginning of rice cultivation thousands of years ago,many efforts have been made to increase rice yield.One of the successes in this history was the Green Revolution.This tremendous improvement in the 1960s was achieved by increasing rice and wheat production through the development and widespread adoption of semi-dwarf varieties with the extensive use of fertilizers(Hedden,2003).Dwarfism in crops lowers the center of gravity of the plant body,reducing the risk of lodging and enabling farmers to use more fertilizer to increase yields.Semi-dwarf mutations in both rice and wheat created during the Green Revolution are related to the plant growth hormone gibberellin(GA).Although other mechanisms cause dwarf mutants,only GA-related semi-dwarf mutants were selected during the Green Revolution(Wang et al.,2021).While GA-related abnormalities only make plants shorter,most cases caused by other mechanisms involve not only dwarfism but also other morphological abnormalities.
文摘Improving grain quality is a primary objective in contemporary rice breeding.Japanese modern rice breeding has developed two different types of rice,eating and sake-brewing rice,with different grain characteristics,indicating the selection of variant gene alleles during the breeding process.Given the critical importance of promptly and efficiently identifying genes selected in past breeding for future molecular breeding,we conducted genome scans for divergence,genome-wide association studies,and map-based cloning.Consequently,we successfully identified two genes,OsMnS and OsWOX9D,both contributing to rice grain traits.OsMnS encodes a mannan synthase that increases the white core frequency in the endosperm,a desirable trait for sake brewing but decreases the grain appearance quality.OsWOX9D encodes a grass-specific homeobox-containing transcription factor,which enhances grain width for better sake brewing.Furthermore,haplotype analysis revealed that their defective alleles were selected in East Asia,but not Europe,during modern improvement.In addition,our analyses indicate that a reduction in grain mannan content during African rice domestication may also be caused a defective OsMnS allele due to breeding selection.This study not only reveals the delicate balance between grain appearance quality and nutrition in rice but also provides a new strategy for isolating causal genes underlying complex traits,based on the concept of“breeding-assisted genomics”in plants.