In order to explore the influence of meteorological factors at different growth stages of grain, this paper firstly chooses winter wheat in Henan province as research object by dividing the winter wheat growth period into nine growth stages according to the phonological map. Then the study selects the yield data and daily average meteorological data of winter wheat in Henan province from 2005 to 2015 and uses the exponential smoothing method to calculate the meteorological yield of winter wheat, and finally establishes the meteorological factors set and the grey relational analysis model to doubly analyze the influence of meteorological factors on winter wheat at different growth stages. The results show that in the case of single analysis, the average relative humidity has the greatest influence on meteorological yield of winter wheat during sowing stage, tillering stage, overwintering stage and grouting stage; the mean wind speed has the greatest influence on meteorological yield of winter wheat during the period of reviving stage, jointing stage and maturing stage; the average daily temperature has the greatest influence on meteorological yield of winter wheat during the seeding stage; the duration of illumination has the greatest influence on meteorological yield of winter wheat during the heading stage. In the case of double quantitative analysis, the meteorological yield of winter wheat is influenced by the average temperature and the daily maximum temperature at the seedling stage, the average relative humidity of at the tillering stage and the overwintering stage, and the mean wind speed of jointing stage. The results are scientific and reliable and could provide evidence for winter wheat production in Henan province.
