摘要
采用 Logistic 生长方程 W=A/(I+Be^(-k■)拟合若干两系杂交稻不同枝梗颖花单位库容的灌浆过程,结合抽穗后的群体物质生产分析,研究组合间的灌浆差异及其生理原因.结果表明:(1)供试组合Ⅰ次和Ⅱ次枝梗之间均存在明显的强弱势灌浆差别,两者灌浆线性期重叠时间长达8-11d,粒位间的营养竞争是普遍存在的.(2)大库容组合可以提高结实期群体叶片的净同化率,发挥叶片的光合潜能.但光合面积较小,库源比仍明显偏大,这是其总体灌浆速率较低、枝梗间差异更大的主要生理原因.(3)不同组合Ⅰ次枝梗前期都具有较强灌浆势和较快启动灌浆的能力,表现营养竞争上的绝对优势.因此组合间其最后库充实率差异之大,可能与颖花机能性障碍的比例多少有关,此外还涉及后期物质转运功能上的差异.
The differences of grain filling on sink basis and the related physiological aspects of some two-line rice crosses were studied with a three-line cross Shanyou 63 as control,using Logistic growth equa- tion,W=A/(1+Be^(-kl)),to simulate the filling processes,in combination with the analysis of the dry mat- ter production after heading.The results were:(1)the great differences of the strong and weak sink filling processes were observed between the Ⅰ and Ⅱ branches of a panicle for all tested crosses;the overlapping pe- riods of linear filling phases of Ⅰ and Ⅱ branches could last for 8-11 days;it was obvious that filling compe- tition for assimilate may commonly exist in a panicle.(2)the crosses with large sink could make a full play for leaf photosynthesis,showing high NAR during the filling period;Yet,the sink/source ratios were remarka- bly higher for these crosses because of much less of the leaf area duration,which may be the main cause why the general filling rates were lower and the filling differences between the strong and weak branches were larger for them.(3)strong(Ⅰ)branches of the tested crosses generally had faster filling starting ability and larger early filling power,indicating perfect superiority for assimilate competition.Therefore the large amounts of difference in sink plumpness would be due to the proportion of the sink with functioning prob- lems and the change of translocation capacity of the crosses.
关键词
水稻
杂交稻
载培
生理
two-line rice hybrid
inter-subspecies rice cross
grain tiding
sink/source ratio
translocation ratio
