2021-2022年渭南市小麦晚播试验OA

To address the delayed sowing of wheat due to continuous heavy rainfall in Weinan City,Shaanxi Province in autumn 2021 and explore stable production strategies under extreme weather conditions,semi-winter variety Xinong 836 and weak spring variety Zhengmai 9023 as test materials,set up eight sowing date gradients,and systematically analyzed the effects of late sowing on wheat emergence,population construction,and yield by dynamically adjusting the sowing rate.The results show that the insufficient accumulated temperature caused by the delayed sowing time leads to significant decreases in the emergence period,leaf age,secondary root number,and regenerative capacity of wheat.However,the weak spring variety Zhengmai 9023 had a significantly lower reduction in the number of spikes than Xinong 836 through the main stem spike compensation effect under extremely late sowing(after December).The stable yield level of Zhengmai 9023 under extremely late sowing(after December)was relatively high,with a maximum decrease of 5.29％compared to the optimal sowing period,while the decrease of Xinong 836 was over 13％.This study provides a scientific basis for variety selection and cultivation regulation under extremely late sowing conditions in the Weinan irrigation area.