水稻覆膜旱作的生态生理效应

Ecophysiological effect of dry cultivated and plastic film mulched rice planting.

研究结果表明，水稻品种在旱作条件下其分蘖期、拔节长穗期、抽穗开花期和灌浆期耐旱性不同，采用地膜覆盖可有效阻挡地面蒸发，节水效率达６０～８５％，生育期延长７～９ｄ，分蘖力增强，最高分蘖数比水作的多１７０１×１０４·ｈｍ－２，有效穗数增加，但每穗粒数、结实率和千粒重下降，其产量水平与水作差异不显著．覆膜旱作水稻前期生长优势强，但后期叶面积指数（ＬＡＩ）、净同化率（ＮＡＲ）、群体生长率（ＣＧＲ）和比叶重等均有所降低，灌浆速度较慢。

The drought endurance of rice was different at its tillering, jointing, earing and filling stages under dry cultivation.Mulching soil with plastic film could effectively resist ground evaporation, save water as much as 60～85%, and prolong growth period 7～9 days. The tillering ability was intensified, with more 170.1×10 4 per hectare tillers than paddy field. The number of effective ears was increased, but the grains per ear, grain setting rate and grain weight were decreased. No significant difference of grain yield was found between dry cultivation field and paddy field. Film mulching on dry cultivation field had a strong superiority at earlier growth stage, but LAI, NAR, CGR and specific leaf weight were decreased at later growth stages, with slow filling speed and low economic coefficient.