Through the analysis of macro-and micro-plant remains,food residues and the rice-field like features from the mid-Neolithic site of Hanjing in the Huai River region,we propose an early beginning of rice cultivation at...Through the analysis of macro-and micro-plant remains,food residues and the rice-field like features from the mid-Neolithic site of Hanjing in the Huai River region,we propose an early beginning of rice cultivation at Hanjing.The presence of non-shattering rice spikelet bases and the increasing percentages of rice phytoliths confirm the appearance of domesticated rice in the Hanjing archaeobotanical assemblage.However,as indicated by the different prediction rates of rice domestication shown by morphometric of the double-peaked Oryza-type glum cells and fish-scale decorations on the Oryza-type bulliform cells from different cultural phases before 7,000 a BP,rice cultivation was at an early stage of development.Our findings provide new and significant evidence towards the establishment of the Huai River as another important center for early rice cultivation and domestication in prehistoric China.展开更多
Due to the remarkable adaptability to various environments, rice varieties with diverse flowering times have abeen domesticated or improved from Oryza rufipogon.Detailed knowledge of the genetic factors controlling fl...Due to the remarkable adaptability to various environments, rice varieties with diverse flowering times have abeen domesticated or improved from Oryza rufipogon.Detailed knowledge of the genetic factors controlling flowering time will facilitate understanding the adaptation mechanism in cultivated rice and enable breeders to design appropriate genotypes for distinct preferences. In this study,four genes(Hd1, DTH8, Ghd7 and OsPRR37) in a rice long-day suppression pathway were collected and sequenced in 154, 74,69 and 62 varieties of cultivated rice(Oryza sativa)respectively. Under long-day conditions, varieties with nonfunctional alleles flowered significantly earlier than those with functional alleles. However, the four genes have different genetic effects in the regulation of flowering time: Hd1 and Os PRR37 are major genes that generally regulate rice flowering time for all varieties, while DTH8 and Ghd7 only regulate regional rice varieties. Geographic analysis and network studies suggested that the nonfunctional alleles of these suppression loci with regional adaptability were derived recently and independently. Alleles with regional adaptability should be taken into consideration for genetic improvement. The rich genetic variations in these four genes,which adapt rice to different environments, provide the flexibility needed for breeding rice varieties with diverse flowering times.展开更多
基金supported by the National Social Science Foundation of China (Grant No. 18CKG002)
文摘Through the analysis of macro-and micro-plant remains,food residues and the rice-field like features from the mid-Neolithic site of Hanjing in the Huai River region,we propose an early beginning of rice cultivation at Hanjing.The presence of non-shattering rice spikelet bases and the increasing percentages of rice phytoliths confirm the appearance of domesticated rice in the Hanjing archaeobotanical assemblage.However,as indicated by the different prediction rates of rice domestication shown by morphometric of the double-peaked Oryza-type glum cells and fish-scale decorations on the Oryza-type bulliform cells from different cultural phases before 7,000 a BP,rice cultivation was at an early stage of development.Our findings provide new and significant evidence towards the establishment of the Huai River as another important center for early rice cultivation and domestication in prehistoric China.
基金supported by the National Natural Science Foundation of China (31300276 for XMZ)
文摘Due to the remarkable adaptability to various environments, rice varieties with diverse flowering times have abeen domesticated or improved from Oryza rufipogon.Detailed knowledge of the genetic factors controlling flowering time will facilitate understanding the adaptation mechanism in cultivated rice and enable breeders to design appropriate genotypes for distinct preferences. In this study,four genes(Hd1, DTH8, Ghd7 and OsPRR37) in a rice long-day suppression pathway were collected and sequenced in 154, 74,69 and 62 varieties of cultivated rice(Oryza sativa)respectively. Under long-day conditions, varieties with nonfunctional alleles flowered significantly earlier than those with functional alleles. However, the four genes have different genetic effects in the regulation of flowering time: Hd1 and Os PRR37 are major genes that generally regulate rice flowering time for all varieties, while DTH8 and Ghd7 only regulate regional rice varieties. Geographic analysis and network studies suggested that the nonfunctional alleles of these suppression loci with regional adaptability were derived recently and independently. Alleles with regional adaptability should be taken into consideration for genetic improvement. The rich genetic variations in these four genes,which adapt rice to different environments, provide the flexibility needed for breeding rice varieties with diverse flowering times.