Effects Of Organic Fertilizer And Foliar Fertilizer On Grape Growth And Fruit Quality

In order to speed up the development of green and sustainable agriculture,China has launched a number of fertilizer reduction policies;Under this situation,the application of organic fertilizer is gradually increasing.Previous studies have shown that soil organic fertilizer and foliar spraying are safer than chemical fertilizer,and have fewer side effects on soil,which are worthy of further promotion and application.The scientific and effective application rates of organic fertilizer and foliar fertilizer are the basis for the rational application and promotion of organic fertilizer and foliar fertilizer.In this study,‘Hutai 8hao’and‘Red Globe’grapes were used as experimental materials to explore the effects of different amounts organic fertilizers,foliar spraying different concentrations of5-aminolevulinic acid（ALA）,fruit spraying different concentrations of ALA,abscisic acid（ABA）,ethephon（ETH）and their mixtures on soil fertility,grape growth and fruit quality related indicators,in order to provide theoretical basis and technical support for green production and rational fertilization of grapes in Shaanxi Province,and reduce production costs as far as possible while improving quality.The main conclusions of this study are as follows:1.Xi’an Urban Agriculture Experimental Station and Heyang,Fangxi Village,Nangou Village,Xinmin Village（3 experimental sites）,a total of four experimental sites were tested by adding organic fertilizer.The results showed that adding organic fertilizer could improve soil physicochemical properties and soil nutrients,promote plant growth and increase fruit quality.In terms of soil physicochemical properties,soil temperature under 5t/666.7m²and 7 t/666.7m²treatments significantly increased by 2.36%and 1.36%,respectively,compared with the control.Organic fertilizer treatment significantly increased soil moisture in Xi’an Urban Agricultural Experimental Station,and soil moisture slightly increased in Heyang three test sites after fertilization.Application of 3 t or more organic fertilizer per mu significantly reduced the surface soil compaction.The application of organic fertilizer increased the contents of soil organic matter,total nitrogen and available nutrients,and the treatment of 5 t/666.7m²and above had the most obvious improvement effect.Organic fertilizer treatment decreased soil p H,Xi’an Urban Agriculture test station after treatment of soil p H below 8.0,Heyang three test points after treatment of soil p H in8.05-8.21 range.In terms of tree growth,chlorophyll SPAD of 5 t/666.7 m²and 7 t/666.7m²treatments were significantly higher than those of the control,increasing by 6.54%and6.74%,respectively.The branch length of 5 t/666.7m²treatment was the longest and the thickest,which increased by 11.46%and 7.27%respectively compared with the control.Internode length,leaf area and leaf thickness were not significantly affected.In terms of fruit quality,when the amount of organic fertilizer applied per mu reached 3 t or more,the fruit spike weight increased,and the spike weight of 7 t/666.7m²treatment increased by25.61%compared with the control.When the application amount was increased to5t/666.7m²and above,the single-grain weight of the fruit was significantly increased,and the treatment of 5 t/666.7m²and 7 t/666.7m²increased by 8.31%and 9.68%respectively compared with the control.5 t/666.7m²treatment had the most significant effect on increasing sugar and reducing acid,and the fruit hardness increased significantly.Based on the results of four experimental points,it was found that there were significant differences in soil state,tree growth and fruit quality between the control and the treatment with 3 t or more organic fertilizer per mu.After continuous increase of fertilizer application amount,the effect of 7 t/666.7m²treatment was not significantly increased compared with that of 5 t/666.7m²treatment.In addition,the application of 7 t organic fertilizer per mu greatly increased the production cost.Combined with the yield and economic benefit evaluation,the effect of 5 t/666.7m²organic fertilizer treatment was the best,followed by that of 3 t/666.7m².2.At the early stage of fruit color transformation,spraying different concentrations of ALA on grape leaves had no significant effect on the increase of chlorophyll content in grape leaves.The net photosynthetic rate,transpiration rate,intercellular carbon dioxide concentration,stomatal conductance and water use efficiency of grape leaves were significantly improved.Under 25 and 40 mg/L ALA treatment,the net photosynthetic rate of leaves increased by 46.75%and 27.00%,the transpiration rate increased by 18.36%and8.06%,the intercellular CO₂concentration increased by 8.9%and 7.00%,the stomatal conductance increased by 34.47%and 27.39%,and the water use efficiency increased by24.24%and 15.91%,respectively.The results of fruit quality measurement showed that ALA foliar spraying could improve the intrinsic quality and color of grape fruit in different degrees.Compared with the control,the soluble solid content of fruits treated with 25 mg/L and 40 mg/L ALA increased by 4.46%and 3.76%,and the titratable acid content decreased by 18.18%and 16.67%,respectively,with significant differences.There was no significant change in total soluble sugar and hardness of fruit;the CIRG of fruits treated with 25 mg/L and 40 mg/L increased by 19.58%and 16.97%,respectively,compared with the control,and the coloring was better than that of the control.3.Foliar application of ALA,ABA,ETH and their mixture improved the fruit quality of grape,increased the content of soluble solids and total soluble sugar,decreased the content of titratable acid and improved fruit coloring.The treatment with AT6（ALA 100mg/L+ABA 300 mg/L）and ET6（ALA 100 mg/L+ETH 400 mg/L）was the optimal.In ALA-ABA combination,the soluble solid content and soluble sugar content of fruits treated with AT6 increased by 11.33%and 10.64%compared with the control,respectively,the titratable acid content decreased by 24.59%compared with the control,and the CIRG of fruits increased by 12.00%compared with the control.In ALA-ETH combination,the soluble solid content and soluble sugar content of ET6 treatment fruit were increased by7.02%and 6.11%compared with the control,respectively.The titratable acid content was decreased by 26.22%compared with the control,and the CIRG of fruit was increased by26.81%compared with the control.4.Foliar spraying different concentrations of ALA solution in autumn increased the chlorophyll content of leaves,the rate of deciduous trees,the length and diameter of branches and shoots,but the effect was not statistically significant.The germination rate of buds,flowering status and basal diameter of new shoots in spring of the second year were better than those in the control group.The germination rate of 40 mg/L ALA treatment was the highest,reaching 90.13%,4.97%higher than that of the control,and the basal diameter of new shoots increased significantly,6.86%higher than that of the control.10 mg/L ALA had the highest flowering rate of 87.73%,which was 12.85%higher than that of the control;overall,40 mg/L ALA treatment was the best.