Effects Of Zinc Application On Yield Formation Of Double Cropping Rice And Characteristics Of Soil Available Nutrients

Rice is the most important food crop in China.Zinc is an indispensable trace element in the growth and development of rice,and it is also an indispensable nutrient for human body.For a long time in China,the phenomenon of heavy fertilizer,light organic fertilizer,heavy element fertilizer,light medium and trace element fertilizer application in rice production is common,resulting in a series of prominent problems such as soil hardening,acidification,decline of organic matter content,decline of soil microbial functional diversity,which seriously affect the soil physiological and biochemical characteristics,Some elements beneficial to human health in the soil are constantly missing.Therefore,it is of great significance to increase grain yield,improve soil fertility,increase beneficial elements of rice and improve quality in double cropping rice area.The effects of T2(100% inorganic fertilizer + 0.5kg zinc fertilizer),T3(100% inorganic fertilizer + 1kg zinc fertilizer),T5(70% inorganic fertilizer + 30% organic fertilizer + 0.5kg zinc fertilizer)and T6(70%inorganic fertilizer + 30% organic fertilizer + 1kg zinc fertilizer)on the growth and development,yield and yield components,zinc content in various organs of double cropping rice were studied The main results are as follows: 1(1)Zinc fertilizer can increase rice yield mainly by increasing 1000 grain weight and seed setting rate.Application of zinc fertilizer could increase dry matter accumulation of panicle and shoot;The results showed that the combined application of zinc fertilizer and organic fertilizer could increase the tiller number,panicle rate,SPAD value of flag leaf,Lai and root activity of rice.(2)Application of zinc fertilizer was beneficial to increase the content of alkali hydrolyzable nitrogen in soil.The content of alkali hydrolyzable nitrogen increased by0.11% ～ 14.55%,available phosphorus increased by 0.06% ～ 33.17%,available potassium increased by 0.07% ～ 14.55%,and available zinc increased by 1.43% ～ 43.94%;The effective nutrient content of organic fertilizer + zinc fertilizer treatment was also higher than that of inorganic fertilizer + zinc fertilizer treatment.(3)The application of zinc fertilizer could promote the transportation of zinc from stem to Panicle at the late growth stage of rice,and promote photosynthesis;There was a positive correlation between the zinc content of vegetative organs and the amount of zinc fertilizer applied at the maturity stage of rice;Compared with the application of inorganic fertilizer alone,the application of inorganic fertilizer combined with zinc fertilizer was more conducive to improve the zinc content of plant root,brown rice and glume.The zinc content of root increased by 4.84% ～ 168.72%,that of brown rice increased by 7.51% ～ 122.22%,and that of glume increased by 5.97% ～ 109.57%.Compared with organic fertilizer and inorganic fertilizer,organic fertilizer combined with zinc fertilizer was more conducive to improve the zinc content of plant root,brown rice and glume.The zinc content of root,brown rice and glume increased by 2.86% ～ 152.09%,18.60% ～ 78.94% and 14.72% ～100.00%,respectively.The zinc content of root,stem,leaf,panicle,brown rice and glume at maturity stage of early and late rice from 2019 to 2020 showed the following rule: root > leaf> stem > panicle > brown rice > glume.The results showed that the application of organic fertilizer and zinc fertilizer could improve rice yield,effective nutrient content and zinc content and accumulation in plant organs;T6(30% organic fertilizer + 70% inorganic fertilizer + 1kg zinc fertilizer)was the best.