机插密度对杂交水稻制种母本群体生长发育特性的影响

Effect of Mechanical Transplanting Density on the Growth and Development Characteristics of the Female Parent Population in Hybrid Rice Seed Production

为了探明杂交水稻制种母本适宜的机插密度,选用湘陵628S、丰源A、广占63S、深95A、Y58S和隆科638S等6个不同生育期和分蘖成穗特性的母本,以人工移栽16.7×20(cm)作对照,研究不同机插密度对母本群体生长发育特性的影响。结果表明:6个母本中随着机插密度的减小,播始历期、抽穗历期及盛穗历期呈延长趋势,穗平颖花数有增长趋势,成穗率则表现为减少趋势,其中抽穗历期与盛穗历期在机插密度处理间差异不显著。单位面积最高苗、有效穗、颖花数在湘陵628S、丰源A、广占63S、深95A中随着机插密度的减小而减小,均以高密度18×14(cm)最高。综合抽穗特性和穗粒构成,湘陵628S、丰源A、深95A、广占63S、隆科638S五个母本均以机插密度18×14(cm)最为适宜,Y58S以机插密度20×14(cm)最为适宜。机插条件下,应根据机插密度对不同特性母本播始历期的影响,相应调整父母本播差期以确保花期相遇。

In order to ascertain the suitable mechanized transplanting density of the female parent population in hybrid rice seed production,the influence of different mechanized transplanting densities on the growth and development characteristics of female parent population were studied,with six chosen female parents,and the control of artificial transplanting(16.7cm×20 cm).The results showed that:as the mechanized transplanting density decreasing,the duration from seeding to heading,heading period and middle heading time of the 6 female parents showed prolonged trend;meanwhile the number of spikelet per panicle of each female parent was increasing,and the spike rate was decreased.There was no significant difference in heading period and middle heading time under four different densities.The highest seedling,effective spike and spikelet numbers of unit area Xiangling 628 S,Fengyuan A,Guangzhan 63 S and Shen 95 A,were decreased as the density decreased,these traits achieved the maximum value when the density was high(18 cm×14 cm).Heading characteristics and spike grain composition of the females were considered comprehensively,the suitable mechanized transplanting density was 14×20(cm) for Y58 S,and the density of 14×18(cm) for other five female parents(Xiangling 628 S,Fengyuan A,Guangzhan 63 S,Shen 95 A and LK638S).In order to ensure flower synchronization of the parents,the sowing gap stage of the female and male parents should be adjusted according to the effect of mechanized transplanting density on the duration from seeding to heading of different female parent.