Effects Of Slow-release Fertilizer Combined With Silicon Fertilizer On Rape Yield,Quality And Soil Bacteria

In recent years,with the continuous development of people’s pursuit of high-quality life,the per capita consumption of edible vegetable oil has increased rapidly.As one of the main oil crops in China,rape has played an important role.Hunan Province is a large rape planting province,but most of the growers in the rape production process are relatively backward in the basic application with topdressing fertilization,resulting in the waste of production costs,reducing the production efficiency.Therefore,in this paper,under the condition of mechanical ridge cultivation,slow-release fertilizer combined with silicon fertilizer foliar spraying was used to fertilize rape,to explore the effect of this fertilization mode on the performance of agronomic traits of rape,rapeseed yield and quality and disease resistance,and to explore the relationship between fertilization and rhizosphere soil microorganisms of rape.The main results are as follows:1.No fertilization will seriously affect the performance of agronomic traits of rape,some agronomic traits of rape were enhanced with the increase of fertilizer amount,and there was a peak of fertilizer increase between 750 kg/hm~2 and 900 kg/hm~2;Compared with the conventional fertilization,the main agronomic traits of rape were not significantly affected when the application rates of slow-release fertilizer were 600 kg/hm~2 and 750kg/hm~2,and the number of leaves in seedling stage,plant height,primary branches,rhizome diameter,pod length and so on still reached a higher level,while the application of silicon fertilizer had little effect on the agronomic traits of rape.2.Through the two-year experiment of slow-release fertilizer and silicon fertilizer,it was found that no fertilizer could significantly reduce the emergence of material accumulation of rape under different soil fertility conditions.Compared with farmers’conventional fertilization,when the slow-release fertilizer was 600 kg/hm~2 and 750 kg/hm~2,the growth rate of rape was higher The results showed that the average density,dry matter accumulation and nitrogen/phosphorus accumulation were 608,800 plants/hm~2,18.90 t/hm~2,259.16 kg/hm~2 and 102.29 kg/hm~2 respectively,which could ensure the density,matter accumulation and nutrient accumulation of mechanical ridging direct seeding rape,so as to provide material basis for the formation of rape yield3.Combined application of slow-release fertilizer and silicon fertilizer can increase pod number per plant,1000 grain weight and yield of rapeseed,and reduce 16.6%and 33.3%respectively based on 900 kg/hm~2 slow-release fertilizer,which is equivalent to or even higher than that of full application of slow-release fertilizer and conventional fertilization.The average yield of rapeseed in two years experiment is 2240.94 kg/hm~2.It was higher than the yield of 1758.68 kg/hm~2 under the farmer conventional fertilization,which can provide an effective way to improve the potential productivity of rapeseed.4.Different soil fertility levels will affect the quality of rapeseeds.Increasing the amount of slow-release fertilizer will increase the protein content and reduce the oil content of rapeseeds,while other factors such as oleic acid,linoleic acid and linolenic acid are less affected by the amount of fertilizer.At the same time,combined application of silicon fertilizer will also reduce the oil content,linolenic acid and glucosinolate content,increase the linoleic acid content,and have little effect on the protein,oleic acid and saturated fatty acid content.5.The application of slow release fertilizer had no significant effect on Sclerotinia sclerotiorum resistance of rape.The natural incidence rate of Sclerotinia Rot in rape pod and harvest stage decreased by 5.01%and 5.19%respectively after applying silicon fertilizer.The application of silicon fertilizer can affect the physiological changes of rape,and help rape resist the infection of Sclerotinia sclerotiorum by reducing the reduction of antioxidant enzyme activity,improving antioxidant enzyme activity and maintaining chlorophyll synthesis in leaves,it can reduce the damage of rape leaves caused by pathogen infection,ensure the normal photosynthesis of leaves,reduce the number of dead plants,and provide an effective way for rape production.6.Combined application of slow-release fertilizer and silicon fertilizer could affect the bacterial community in the rhizosphere soil of rape,the results showed that the application of slow-release fertilizer could reduce the complexity and specificity of rhizosphere soil bacterial community at seedling stage,but increase the complexity and specificity of rhizosphere soil bacterial community at harvest stage,application of silicon fertilizer could increase the diversity and richness of bacterial community in the rhizosphere soil of rape at seedling and harvest stages,So,combined application of slow-release fertilizer and silicon fertilizer can promote the nutrient absorption of rape by affecting the flora related to plant nutrient absorption in soil bacterial community.