Effect of Water Layer on Rice Seedling Emergence Under Different Sowing Depth in"Dry Sowing and Wet Seedling"Mode of Direct-seeding Rice

CHEN Xiandong; WU Xiangdong; YANG Wanxin

doi:10.14069/j.cnki.32-1769/s.2025.01.005

Abstract：With the development of modern agriculture,the improvement of mechanization degree,and the development of rice mechanical direct seeding technology,seedling emergence in direct-seeding rice is one of the main factors for high yield of direct seeding rice.In this experiment,the influence of sowing depth and water layer on rice emergence was studied under the mode of"dry sowing and wet seedling"of direct seeding rice,so as to screen out the most suitable sowing depth and water layer and increase the seedling preservation rate of direct-seeding rice,and achieve high yield.The results showed that the membership function was 0.949 when the sowing depth was 0 cm and the water layer depth was 0 cm,which was the best among all treatments,indicating that it was the most beneficial to rice emergence and seedling growth.The key of"dry sowing and wet seedling"planting is seedling preservation.Under the"dry sowing and wet seedling"method,the rice seedling emergence rate decreased with the increase of sowing depth and water layer.When the sowing depth was 0 cm,the rice emergence was less affected when the water layer was less than 2 cm,and the rice emergence was more obviously inhibited when the water layer was 5 cm.When the sowing depth was 2 cm,the emergence of rice in the 0 cm water layer was affected,but the effect was not obvious.When the water layer was increased to 2 cm,the emergence rate was inhibited.When the water layer was increased to 5 cm,the emergence rate of rice was significantly decreased and severely inhibited,which ultimately had a greater impact on rice yield.Therefore,in the case of shallow sowing in field production,it is necessary to consider the influence of the seeds exposed on the soil surface and other factors such as bird damage.In order to ensure the seedling preservation rate,the water layer should be properly maintained under the condition of shallow sowing.