高温对玉米花粉活力的影响

Effects of high temperature on maize pollen viability

采用离体玉米花粉高温处理的方法模拟自然条件下高温对花粉的危害,首先在大田条件下种植郑单958作为材料,在散粉期采粉并对其进行高温处理。共设置3个温度处理(32、35、38℃),5个持续时间处理(5、10、20、30、60min),同时设定常温对照(CK)。研究测定了花粉经高温处理后氯化三苯基四氮唑(Triphenyl tetrazolium chloride,TTC)染色率、小花受精率和总结实率,以反映高温对花粉活力的影响。结果表明:温度、处理时间及互作对花粉活力均有极显著影响,32和35℃情况下花粉活力持续时间较长,38℃和处理1h对花粉活力的伤害均较大。随着温度的升高,小花受精率和总结实率总体上呈降低的趋势;3个温度水平下的小花受精率和总结实率均随着处理时间的延长而降低,当温度达到38℃或处理时间为1h时,小花受精率和结实率都很低,反映出极端高温或持续高温对花粉活力伤害很大。

In this study,maize was planted under simulated nature environment condition and pollens were sampled after silking.Pollens were cultivated in vitro under 3different high temperatures（32,35 and 38℃）and 5different length of treatment duration（5,10,20,30 and 60 min）under each temperature.The impact of high temperature on pollen viability was reflected by TTC staining rate,florets fertilization rate and setting rate.The TTC staining results indicated that temperature,length of treatment duration,and their interaction affected pollen viability significantly.Pollens maintained to be active for longer time under 32 ℃ and 35 ℃,while under 38 ℃ or 1htreatment duration under 38 ℃damaged pollen viability seriously.With the increase of temperature,the florets fertilization rate and setting rate were reduced under all treatment durations.With the increase of treatment duration,the florets fertilization rate and the setting rate were reduced under all temperatures.The florets fertilization rate and the setting rate were very low under 38℃ or1 htreatment duration indicating extreme temperature or long-term high temperature could harm pollen viability seriously.