Abstract:

In order to explore the effects of sowing date on the growth and development and yield formation of naked oats and provide a basis for optimal sowing and high yield of naked oats in agro-pastoral ecotone, effects of different sowing dates on phenology, morphological index and yield formation of naked oats were studied using randomized block design based on two-year experiments including three treatments of sowing date in Wuchuan County. The results showed that: phenology, plant height and leaf area per plant were significantly different under different sowing dates, plant height and leaf area per plant under the treatments of middle-sowing and late-sowing were higher than the treatment of early-sowing. With the sowing date postponed, the vegetative growing period of naked oats was shortened due to the increase in temperature, whilst the reproductive growing period was increased due to increasing rainfall. The whole period of growth was shortened and the ratio of reproductive growing period to the whole growth period was increased. The tiller number per plant, panicle number per plant, and 1000-grain weight changed significantly under different treatments of sowing date. In the two-year experiment, the yield of the middle-sowing naked oats was 107.7 g/m2, higher than that of the early-sowing and the late-sowing naked oats. The appropriate sowing date of naked oats was recommended to be arranged in near May 18th.