Abstract:

In order to study the effects of meteorological conditions on the internal quality and appearance quality of sunflower seed kernels in Hetao Irrigation District, using the staged sowing experiment to record the development period of sunflowers, and the contents of linoleic acid and oleic acid in sunflower kernels were tested. The incidence of sunflower kernel rust spots, disease index and sunflower borer feeding rate were counted. Using Excel, the numerical relationship between the internal and external quality of sunflower kernel and meteorological conditions was analyzed. The results showed that the sowing date had obvious influence on the inner quality and appearance of sunflower. Considering these two aspects, the best sowing date should be from May 25 to June 2. When the sunshine duration from flowering to maturity was 393.3-396.4.8 h, the content of linoleic acid could be greatly increased and the content of oleic acid could be reduced. When the average relative humidity from flowering to maturity was 58%-59%, the quality of sunflower could be significantly improved. When the average temperature from flowering to maturity was 19.0-20.8℃, the inner quality and appearance of sunflower were obviously improved. Precipitation from flowering to maturity had significant effects on sunflower quality. When precipitation was 42-44 mm, the content of linoleic acid in sunflower was greatly increased. When the precipitation was 46.9 mm, the gnawing rate of moth was the lowest. Precipitation, relative humidity and water vapor pressure at flowering stage were negatively correlated with the occurrence index of sunflower rust spot. With the increase of moisture and humidity, the number of drought-fond pest thrips decreased sharply, so the incidence index of rust spot decreased.

Key words: sunflower, meteorological conditions, seed kernel, linoleic acid, oleic acid, sunflower kernel rust, kernel intrinsic quality, rate of moth eating, kernel appearance quality