Straw Decomposition And Nutrient Release In The Main Season Rice And Its Effect On The Yield Formation Of To Ratoon Season Rice

In order to clarify the effects of straw returning to the field in the first season on the growth and yield of rice in the regeneration season,a field experiment was carried out in Qian Shan Hong Town,Da Tong Hu District,Yi Yang City,Hunan Province in 2019.Split plot design was used,the species is given priority to area,returning processing(straw counters-field +conventional irrigation,straw returned wet irrigation,straw returned,flooding irrigation,irrigation rotten straw counters-field wet agent.Irrigation + rotten straw counters-field +flooding agent)as deputy district,Yong you 4149 and Y liang you 911 varieties tested,the main results were as follows:1.Water management and the use of decaying agents accelerated the decomposition rate of straw after returning to the field,thus promoting the release of nitrogen,phosphorus and potassium elements.The release rates of N,P and K in rice straw increased by 50.1%-70.8%,12.4%-23.8% and 23.5%-44.0%,respectively,compared with no application of decaying agent.In addition,the release rates of N,P and K in rice straw increased by 23.1%-40.1%,0.4%-18.1% and 22.8%-43.3%,respectively,when wet irrigation was more beneficial to nutrient release than when flooded irrigation.2.The straw returning promoted the nutrient accumulation at the mature stage of rice in the regeneration season,and moisture irrigation and use of decaying agents can further increase plant nutrient content.Compared with the control,the nitrogen content in stem,leaf and ear of Yong you 4149 was increased by 71.7%,39.2% and 56.1% by straw returning +wetting + ripening agent,respectively.Compared with the control,the phosphorus content increased by 142.9%,9.2% and 52.2%,respectively.And potassium content increased by35.0%,47.2% and 16.2%,respectively,compared with the control.The nitrogen,phosphorus and potassium contents of stem,leaf and panicle treated with straw returning + wetting +ripening agent were not significantly different from those of the control group at the maturity stage of Y liang you 911 rice regeneration season.3.Compared with the control without returning to the field,The seedling pile ratio and ear pile ratio of straw returning treatment increased by 6.1%-66.4% and 24.1%-40.3%,respectively,compared with that of non-returning treatment.Wetting irrigation and application of decaying agent after straw returned to the field further improved the seedling and panicle capacity of rice in the regenerating season.The comprehensive analysis showed that straw returning + wet irrigation + application of decaying agent had the best effect on improving the seedling development ability of rice in the regeneration season,and the seedling pile ratio,panicle pile ratio and regenerative power of rice increased by29.4%-66.4%,29.4%-37.9% and 24.8%-30.3%,respectively,compared with the control without returning to the field.4.The addition of decaying agent after straw returning to the field increased the rice yield in the regeneration season by 6.0%-19.7%.The yield under wet irrigation had no significant difference compared with that under flooded irrigation(except that Y Liangyou911 was treated with decaying agent).The comprehensive analysis showed that straw returning + wetting irrigation + decaying agent application had the best effect on rice yield increase in the regeneration season,and the yield increased by 19.0%-42.3% compared with the control.From the perspective of yield components,the yield difference among different returning treatments mainly came from the difference of effective panicles per unit area.In conclusion,the straw returning to the field accelerated the straw decomposition rate,promoted the nutrient accumulation in the mature stage of rice in the regeneration season,and increased the regenerated seedling and panicle capacity of rice in the regeneration season,so as to further improve the yield.Wetting irrigation and use of decomposing agent can further increase straw decomposition rate,plant nutrient content,seedling regeneration and panicle formation ability,thus increasing yield.