高产水稻品种的物质生长特性

Analysis of Dry Matter Production in High Yielding Rice Cultivars

本试验于１９９５年在云南省丽江地区永胜县涛源乡进行，研究了每公顷实收７．４７～１４．３３吨的６个籼稻品种的物质生长特性。结果表明：①生物产量的差异主要出现在抽穗以后，生物产量高的品种，籽粒产量也高，者的相关性达极显著（ｒ＝０．９５７９＊＊）。②抽穗后光合产物对产量的贡献大于运转量的贡献，然而产量却随着运转量的增加而提高。③群体生长率（ＣＧＲ）在水稻生长过程中出现３次高峰，分别在穗分化期、开花期和收获期；不同品种ＣＧＲ的差异主要出现在某一生长期的结束阶段；④穗分化前，ＣＧＲ主要受叶面积指数（ＬＡＩ）的限制；穗分化以后，主要受净光合速率（ＮＡＲ）的限制。

Field experiment was conducted at Taoyuan township,Lijiang Prefecture of Yunnan Province in 1995.Six high yielding rice cultivars were grown under optimum crop management to achieve maximum yield.Plants were sampled from transplantation to maturity.After the number of panicles were accounted,the samples were separated into leaf,stem and panicle to determine biomass,yield and leaf area index(LAI).The crop growth rate(CGR)and the net assimilation rate(NAR)were computed.That's showed:The biomass variation in different cultivars appeared after anthesis.The higher the biomass at maturity,the higher the grain yield (r=0 9579  ).Photosynthesis during flowering to maturity period contributed more to yield than transported matter from leaf,stem and sheath did;but yield increased with the increase of transported matter.Three peaks of CGR were observed in the whole rice growth period.They rose at panicle differentiation,flowering and maturity.Each peak appeared at the end of one phase when the variation of CGR in different varieties were large.Before panicle differentiation phase,CGR varied with LAI,but after that period CGR increased with NAR.