两系杂交稻栽培生理生态特性 Ⅱ.干物质生产特性

研究表明,供试组合W6154s/特青、亚优2号和光优6028生育前期具有较强的物质积累能力;其中W6154s/特青和光优6028前期群体生长率(CGR)高主要与叶面积指数(LAI)发展较快有关.部分原因是它们前期积累的干物质对叶片的分配率明显高于对照;而亚优2号前期CGR高除了叶面积有明显作用外,与较高的净同化率(NAR)也有一定关系.W6154s/特青和亚优2号主要由于后期适应性差,物质生产变劣,故实际产量不如对照汕优63.光优6063生育前、中期群体物质生产与对照威优64相近,但产量明显提高,其主要原因在于后期适应性强,能维持较高的LAI和NAR.光优6028虽然后期物质生产性能也较好,但产量不如光优6063,可能主要与物质运转效率偏低有关.

Studies on Agro-physio-ecological Characteristics of Two-line Rice Hybrids Ⅱ. Characteristics of Dry Matter Production and Partitioning

The experiment was conducted under field conditions in 1990 to test dry matter production and partitioning characteristics of some two—line rice hybrids (F_1), including indica / sinica and indica / indica crosses, with three—line indica crosses Shanyou 63 (CK_1) and Weiyou 64 (CK_2) as controls. Dry matter prodution at the tillering stage was higher in W6154s/Teqing (indica/indica), Yayou 2 (indica/sinica) and Guangyou 6028 (indica/sinica) than that in corresponding controls. The higher crop growth rates(CGRs) in W6154s/ Teqing and Guangyou 6028 were mainly due to their larger leaf area indices (LAIs) at the tillering stage, and these can be attributed to more dry matter partitioning to the leaves at this stage; while the higher CGR in Yayou 2 was due to both LAI and net assimiration rate (NAR). Actual grain yield decreased remarkably in W6154s/Teqing and Yayou 2 as compared with that in CK_1 owing to the poor adaptation to in situ ecological conditions at the ripening stage, which resulted in the low dry matter production ability. Dry matter production at both the tillering and panicle development stages in Guangyou 6063 (indica/indica) was the same as that in CK_2, but grain yield was remarkably higher in the latter. This could be attributed to the larger LAI and higher NAR in Guangyou 6063 at the ripening stage, which highly adapted to in situ conditions. Dry matter production in Guangyou 6028 was nearly the same as but its grain yield was much lower than that in Guangyou 6063; this could be due to the lower dry matter translocation efficiency in the former.