关键词: 晚霜冻, 产量, 穗粒数, 冬小麦, 特征空间

Abstract: Late frost, a kind of sudden low temperature agricultural meteorological disasters, occurred with different degrees in nearly years in Huanghuai wheat area of China and had a significant impact on winter wheat yield. According to the severe late frost of winter wheat in Shangqiu in 2013, this paper analyzed the influence of late frost toward winter wheat yield components using MODIS atmospheric profile retrieval products. Firstly, surface temperature (ST) and water vapor of lower atmosphere layer (WVL) series data of the MYD07_L2 products were selected to analyze the process of late frost. Then, some indexes were chosen from temperature and humidity to make a correlation analysis combining with the measured data from frost-damaged wheat. Finally, feature space of temperature and humidity were built using the correlation analysis results to analyze the effect of low temperature and humidity on yield components. The results showed that ST and WVL could reflect the meteorological environment of winter wheat growth. The dates of extreme low temperature matched actual late frost dates well and late frost occurred with the lower temperature and humidity condition. Temperature minimum less than 0℃ had obvious correlation with the grains per spike. The combination of temperature less than 0℃ and humidity obvious overlapped effects on the grains per spike. The results provided a basis for early prediction of impact on winter wheat yields caused by frost after jointing stage.

Key words: late frost, yield, grains per spike, winter wheat, feature space