Effects Of Combined Application Of Humic Acid On Physical And Chemical Properties Of Vineyard Soil And Fruit Quality

The growth of grape plants requires a lot of nutrients.Fertilization is mainly used to supplement nutrients in production.However,there are many problems with fertilization in production.Too much chemical fertilizer is used and the fertilizer utilization rate needs to be further improved.This research uses 4 years old’Summer Black’grapes in the vineyard of Sichuan Agricultural University modern agricultural research and development base as test materials.Reduce the application of nitrogen fertilizer and increase the application of humic acid on the basis of formula fertilization.The normal fertilization amount of nitrogen fertilizer is 50 kg.Set 4 different reduction levels（5%reduction,10%reduction,15%reduction,20%reduction）,and set 3 concentrations of water-soluble fertilizers containing humic acid（300 times,500 times,700 times）.Using conventional formula fertilization（CK）as a control.To study the effect of combined application of humic acid on the physicochemical properties of vineyard soil and fruit quality,and to provide theoretical and practical basis for the reduction of fertilizer application in production.The research results are as follows:1.The combination of humic acid and nitrogen fertilizer had different effects on the physical and chemical properties of the soil.After the treatment of humic acid combined with nitrogen fertilizer,the soil p H was lowered in each treatment,and the effect of applying humic acid 500 times+15%nitrogen reduction was the best,which was reduced to 7.22.After fruit picking,the content of soil organic matter,alkali-decomposed nitrogen,available phosphorus,and available potassium at 0-60 cm is better combined with the application of humic acid 300 times+5%nitrogen reduction.The organic matter content is close to the base value.The content of alkali-decomposed nitrogen and available phosphorus increased by 6.41%and 32.37%respectively compared with the base value.The content of available potassium is at a high level and higher than CK.Soil ammonium nitrogen combined with humic acid 300 times+10%nitrogen reduction is better,which is69.60%higher than the control.The effect of soil calcium exchange with humic acid 700times+10%nitrogen reduction is better,which is 41.34%higher than the base value.The content of nitrate nitrogen and exchangeable magnesium in the soil is better by applying humic acid 300 times+reducing nitrogen by 15%.The contents of soil nitrate nitrogen and exchangeable magnesium have increased from the base value.2.Humic acid combined with nitrogen fertilizer can effectively improve soil enzyme activity.Among them,the combined application of humic acid 300 times+5%nitrogen reduction has a better overall effect on increasing soil urease,invertase and acid phosphatase.After fruit picking,its content increased by 1.06 mg/g,1.74 mg/g and 10.76mg/g respectively.3.Humic acid and nitrogen fertilizer can effectively increase the content of mineral elements in leaves to a certain extent.Combined application of 300 times of humic acid+5%reduction of nitrogen has the best effect on increasing total nitrogen,total phosphorus,total potassium,total calcium and total magnesium of leaves.Compared with CK,it increased by 1.67%,1.66%,0.95%,0.04%and 0.06%respectively.4.Humic acid combined with nitrogen fertilizer can increase the partial productivity of nitrogen fertilizer.Combined application of 300 times of humic acid+reduction of nitrogen by 20%has the best performance in terms of partial productivity of nitrogen fertilizer,fertilizer saving amount and fertilizer saving potential.Compared with CK,it increased significantly by 26.53%,150 kg/hm~2and 20%respectively.5.Humic acid combined with nitrogen fertilizer has different effects on fruit quality.The effect on appearance quality is not significant.In terms of the internal quality of the fruit,the application of 300 times of humic acid+5%of nitrogen reduction has a better effect on increasing the content of vitamin C,anthocyanin and total phenol in the fruit.Compared with CK,its content increased by 12.43%,47.15%and 20.47%respectively.Through the main component analysis of soil components,soil enzymes,leaf mineral elements,and the main component analysis of the intrinsic quality of fruits,combined application of 300 times of humic acid+5%nitrogen reduction has the best comprehensive performance in all aspects.