【摘要】 1982～1987年,在湘中的长沙。湘北的常德和湘南的郴州3地区,对威优35,威优49。威优64和威优6号等杂交水稻组合物质生产特性进行研究的结果表明:杂交稻的干物质产量有2个高峰播种时段,即4月上旬和7月上旬;生育后明干物质积累受播种期影响大;湘北地区杂交稻生育前期的干物质积累多;群体净同化率在生育前、中期随纬度升高而降低,在后期则表现相反;籽粒产量与干物质积累,以及干物质积累与净同化率之间均存在显著相关;干物质积累、净同化率与温度、日照的相关性显著。湘北地区杂交水稻产量较低与其生育前期于物质积累较多,中,后期积累较少。且物质运转率(经济系数)低相关。更多还原

【Abstract】 Studies of matter production chracteristics of 4 combinations ofhybrid rice were carried out at 3 sites in Hunan Province in 1982~1987. Twosowing times (early April and early July) arc related to high dry matter yield.Great influence of sowing time on dry matter accumulation takes place at lategrowth stage. Hybrid rice in the north of Hunan Province accumulates more drymatter at early growth stage than at middle and late growth stages. With theincrease of latitude, net assimilation rate (NAR) decreases at early and middlegrowth stages, but at late growth stage it increases. Correlations between drymatter accumulation and the yield and NAR are positive. The multiple regressionrelationships of dry matter accumulation or NAR to temperature and soiar radia-tion are remarkable. Rapid dry matter accumulation at early growth stage butslow at middle and late growth stages plus small harvest index lead to low yieldof hybrid rice in the north of Hunan Province.更多还原