孕穗期高温对粳稻穗部性状的影响

Influence of High Temperature on Panicle Characters of Rice During Booting Stage

随着全球气候变暖,高温热害已成为水稻高产稳产的主要因素之一。为明确粳稻孕穗期遭遇高温对不同粒重的水稻品种穗部性状的影响程度,以小粒品种千重浪2号和大粒品种润宇1号为试材,在孕穗期按照叶龄余数划分了3个不同生长阶段,在盆栽条件下设定高温处理的温度和时间为(35±1)℃(9:00-15:00)和(27±1)℃(15:00-9:00),研究孕穗期不同生长阶段高温胁迫对水稻穗部性状的影响。结果表明,孕穗期高温胁迫使参试品种的穗长、着粒密度、一次枝梗长、一次枝梗数、二次枝梗数、穗粒数、结实率和千粒重都有不同程度的降低;孕穗期高温主要降低了穗中部和下部的二次枝梗数、穗粒数和结实率,对一次枝梗的影响相对较小。北方粳稻在叶龄余数1.0时如果遭遇高温对穗部性状的影响程度最大,进而影响其高产稳产。

With global warming,high temperature and heat damage has become one of the main factors in affecting the high and stable yield of rice.To clarify the impact of high temperature stress during the panicle initiation stage on the panicle characteristics of rice varieties with different grain weights,small-grain variety Qianchonglang 2 and large-grain variety Runyu 1 were used as test materials.Three different growth stages were divided according to leaf age residue during the panicle initiation stage,and high temperature treatment was set under potted conditions at(35±1)℃(9:00-15:00)and(27±1)℃(15:00-9:00).The study investigated the effects of high temperature stress during different growth stages of the panicle initiation stage on the panicle characteristics of rice.The results showed that high temperature stress during the panicle initiation stage caused a varying degree of reduction in panicle length,grain density,primary branch length,primary branch number,secondary branch number,grain number per panicle,seed setting rate,and 1000-grain weight of the test varieties.High temperature stress during the panicle initiation stage mainly reduced the number of secondary branches,grain number per panicle,and seed setting rate in the mi ddle and lower parts of the panicle,with a relatively small impact on primary branches.If rice is exposed to high temperature stress at a leaf age residue of 1.0,it will have the greatest impact on panicle characteristics,which will in turn affect its high and stable yield.