孕穗期高温对水稻生理特性和产量性状影响研究

为探索水稻孕穗期高温对生理生化特性和产量性状的影响,降低水稻生长发育过程中孕穗期高温对水稻的危害提供理论依据。以‘泰优553’和‘隆晶优1212’为材料,在孕穗期幼穗分化Ⅳ-Ⅵ期利用人工气候室以29、32、35、38℃处理7天,以同时期田间自然温度条件作对照（CK,平均温度30.6℃）,研究孕穗期不同温度对水稻生理特性和产量性状的影响。与对照相比,38℃处理显著降低了‘泰优553’和‘隆晶优1212’的可育花粉数和可育率,可育率分别比对照下降了60.2%、54.7%。随温度的升高,2个品种的脯氨酸和丙二醛(MDA)含量呈上升趋势,在38℃处理显著高于对照(CK)和其他处理,过氧化物酶(POD)活性呈先上升后下降的趋势。高温处理显著降低了2个品种的结实率、千粒重和产量,但对有效穗影响较少。水稻孕穗期高温能显著降低可育花粉数和可育率,同时影响幼穗生理指标的变化,致使结实率和产量下降,不同品种对高温危害的表现存在差异。

Effects of High Temperature at Booting Stage on Physiological Characteristics and Yield Traits of Rice

To explore the effects of high temperature on physiological and biochemical characteristics and yield traits of rice at booting stage, and to provide a theoretical basis for reducing the harm of high temperature to rice at booting stage during rice growth and development, ‘Taiyou 553’ and ‘Longjingyou 1212’ were taken as materials, the effects of different temperatures at booting stage on physiological characteristics and yield traits of rice were studied by using artificial climate chamber of 29℃, 32℃, 35℃ and 38℃ for 7 days at IV-VI stage of young panicle differentiation, and natural temperature condition in field at the same time was used as control (CK, average temperature of 30.6℃). Compared with the control, 38℃ treatment significantly decreased the fertile pollen number and fertility rate of ‘Taiyou 553’ and ‘Longjingyou 1212’, and the fertility rate decreased by 60.2 % and 54.7 %, respectively. With the increase of temperature, the content of proline and malonaldehyde (MDA) of the two varieties showed an upward trend, which were significantly higher than those of CK and other treatments at 38℃. The peroxidase (POD) activity showed a trend of first increase and then decrease. High temperature treatment significantly reduced seed setting rate, 1000-grain weight and the yield of the two varieties, and had little effect on effective panicles. High temperature at booting stage of rice can significantly reduce the number of fertile pollen and fertility rate, and affect the change of physiological indexes of young panicles, resulting in the decrease of seed setting rate and yield. Different varieties have different responses to high temperature damage.