不同施肥处理下北方杂交粳稻干物质积累转移特性及其与产量关系

Dry matter accumulation,transportation and their relationships with yield of japonica hybrid rice in northern China under different fertilization conditions

为了探究北方杂交粳稻具有生物量大、抗逆性强而产量优势不突出的原因,以140份恢复系材料与不育系辽99A杂交组配而成的140个杂交粳稻组合为试材,通过田间小区对比试验,设置正常肥力(施加底肥、蘖肥和孕穗肥)和低肥(仅施加底肥)两种施肥量处理,对杂交粳稻在不同施肥处理条件下干物质积累转移的特性及其与产量关系进行了研究。结果表明:结实率低、千粒重小是制约杂交粳稻产量优势发挥的主要限制因素;杂交粳稻产量更依赖齐穗期后干物质的生产;低肥条件下杂交粳稻茎和鞘部干物质输出率增加,而叶片干物质输出率减少。降低茎部积累干物质的输出率、增加叶片干物质输出率的相差值,有利于降低不同肥力条件下产量的差值,提高杂交粳稻的耐低肥特性优势,为杂交粳稻抗逆性选择育种提供依据。

To explore the reasons for the large biomass and strong stress resistance but no outstanding yield advantage of japonica hybrid rice,140 hybrid combinations of japonica hybrid rice,which were cross-fertilized from 140 restorer lines and BT-type cytoplasmic male sterility(BT-CMS)line Liao-99 A,were used to examine dry matter accumulation,transportation and their relationships with yield under two fertilization treatments:normal fertilization(including basic fertilizer,tillering fertilizer and spike fertilizer)and low fertilization(including basic fertilizer only).The results showed that lower seed setting rate and 1000-grain weight were the most important factors limiting the yield advantage of japonica hybrid rice.The yield of japonica hybrid rice was more dependent on dry matter accumulation after full heading stage.Under the low fertilization treatment,dry matter export percentage from stem and sheath increased and that from leaf decreased.Reducing the export percentage of dry matter accumulation in stem and increasing that in leaf were beneficial to decrease the yield discrepancy under different fertilizer treatments and promote the superiority of japonica hybrid rice in tolerating low-fertility.Our results could provide important insights in the selection of resistance breeding of japonica hybrid rice.