水稻本田分蘖期受旱对其生育影响的研究

以汕优 6 3为材料 ,研究了本田分蘖期不同干旱时间与水稻生长关系。结果表明 :①栽秧当日开始受旱 2 0d以上 ,显著地抑制了分蘖的发生 ,表现为最高苗和有效穗数不足而减产 ;栽后 2 0d开始受旱 10d以上 ,颖花严重退化 ,以致着粒数和结实率降低而减产 ;②水稻分蘖期受旱影响产量的土壤水分临界值为相对含水量 36 %左右 ;③从稻田开始受旱到土壤含水量下降到影响水稻产量的临界值所需积温为 312 76℃。

Effects of the Dried Rice Field on Rice Growing During Tillering Stage

The relation between different dry days for rice field and rice growing were studied with the hybrid rice Shan You 63. The results are as follows: ①Rice field is dried for above 20 days after rice seedling transplanting date, rice tillers are decreased so that the productive panicles are not enough and the grain yield is significantly decreased; Rice field is dried for above 10 days starting from 20 days after transplanting date, the grain yield is significantly decreased because the spikelets per panicle and seed setting rate are reduced. ②The contents of water in paddy soil that starts to fignificantly affect rice growing is about 36%. ③The accumulating temperature from rice field starting were dried to the contents of water in paddy soil recreased at below 36% was 312.76℃.