Effects Of Combined Application Of Nitrogen And Silicon On Growth,yield And Nutrient Utilization Of Giant Rice

Compared with ordinary rice,giant rice has higher straw height,more tillers,more grains per spike and 2.23 m plant height.In addition,giant rice has higher crude fiber content,which can provide higher biomass for livestock and has animal feed potential.However,giant rice with high biomass,multiple tillers and high yield performance has a high demand for growth environment and nutrition.With the continuous development of new varieties of giant rice,the area of production promotion is also increasing(a large number of planting in southern China),the high-yield potential in practice has not been fully exploited,and the yield growth is stagnant,It reflects that the current in-depth study and understanding of the characteristics and breeding technology of giant rice is far from enough.The combination of nitrogen and silicon fertilizer can greatly promote the growth and development of rice,promote more effective panicles,and expand the output value.However,the suitable proportion of nitrogen and silicon fertilizer is often adapted to local conditions.Because of the vast territory of China,the soil texture and physical and chemical properties of different regions are far different,the selection of appropriate proportion of nitrogen and silicon fertilizer can promote the output value of rice per mu to the greatest extent.Therefore,in order to explore the effects of nitrogen and silicon fertilizer application on the growth,yield and nutrient utilization of giant rice,a field randomized block design was adopted in this study.The giant rice "Fengchao 6" was used as the test material,and phosphorus and potassium fertilizer was used as the base fertilizer.Four treatments of nitrogen or silicon fertilizer combination were set: no nitrogen and silicon fertilizer(CK),nitrogen fertilizer(N),nitrogen fertilizer combined with low silicon fertilizer(NSi1)and nitrogen fertilizer High silicon fertilizer(NSi2)was applied.In order to provide a theoretical basis for ensuring the high yield and quality of giant rice production.Here is the main research results below:(1)Compared with CK treatment,the yield of giant rice was significantly increased by12.6%～42.0% with N and Si application alone,and NSi2 treatment had the highest yield.Compared with the application of nitrogen fertilizer alone,the combined application of nitrogen and silicon significantly increased the yield of giant rice by 26.1%;Nitrogen and silicon fertilizer significantly increased the effective panicles,grains per panicle and 1000 grain weight of giant rice by 26.9%～51.2%,9.0%～23.0% and 4.9%～8.8%,respectively.Compared with nitrogen application alone,NSi2 treatment had the highest yield and its components,which indicated that NSi2 treatment was more conducive to yield improvement.(2)Compared with CK treatment,single application of nitrogen fertilizer and combined application of nitrogen and silicon significantly increased the agronomic efficiency and nitrogen use efficiency of nitrogen fertilizer.High amount of nitrogen and silicon fertilizer had the strongest promoting effect.Compared with NSi1 treatment,NSi2 treatment increased the agronomic efficiency and nitrogen use efficiency of nitrogen fertilizer by 9.7%and 16.5%,respectively.The results showed that high silicon fertilizer could promote the effective use of nitrogen fertilizer at the same nitrogen level.(3)After 90 days of transplanting,compared with CK treatment,the content of soil alkali hydrolyzable nitrogen increased by 4.7%～14.1% with the application of nitrogen and silicon alone,and the increase of soil alkali hydrolyzable nitrogen was the largest with the application of nitrogen alone;Soil available silicon content decreased with rice growth,and was mainly affected by nitrogen and silicon fertilizer application.Nitrogen and silicon fertilizer application significantly increased the content of soil available silicon;Compared with nitrogen application alone,soil available silicon increased by 10.2% and 30.8% under NSi1 and NSi2 treatments,respectively.(4)Compared with CK treatment,the starch content,soluble total sugar content and soluble reducing sugar content of rice grains were increased by 14.6%～22.1%,20.9%～52.3% and 14.1%～21.8% respectively by applying N fertilizer and Si fertilizer alone.And with the increase of silicon fertilizer,the starch content,soluble total sugar content and soluble reducing sugar content of rice grain decreased,which indicated that the starch content,soluble total sugar content and soluble reducing sugar content of rice grain were more sensitive to nitrogen fertilizer combined with high silicon fertilizer.(5)Compared with nitrogen application alone,the contents of Fe,CA,Cu,Mg and Mn in rice straw were further increased by 13.2%～36.8%,12.9%～19.1%,27.9%～41.5%,2.2%～12.6% and 19.4%～20.4% under the same nitrogen application level,indicating that appropriate silicon application could increase the contents of Fe,CA,Cu,Mg and Mn in rice straw.In conclusion,nitrogen fertilizer combined with high silicon fertilizer(NSi2)had the best effect on giant rice.