Effects Of Liquid Fertilizer Application Amount On Tomato Growth And Soil Environment Under Organic Cultivation

The effects of topdressing liquid organic fertilizer on tomato growth and soil environment were studied under the conditions of organic cultivation and drip irrigation facilities in greenhouse land cultivation,so as to provide theoretical reference for application of liquid organic fertilizer in organic agricultural production.The "Guanghui 101" tomato variety was used as the test crop,and earthworm liquid fertilizer（F）and homemade chicken manure liquid fertilizer（G）were selected as the test fertilizers.Six organic liquid fertilizers(0（F1,G1）,50（F2,G2）,100（F3,G3）,150（F4,G4）,200（F5,G5）and 250（F6,G6）kg·hm^-2 were used to determine plant morphology,nutrient absorption,yield and quality,soil physicochemical and biological indexes.The effects of earthworm liquid fertilizer and chicken manure liquid fertilizer on tomato growth and soil environment were studied.The results show that:1.Effects on growth,yield and quality of tomato.Both commercial earthworm liquid fertilizer F and homemade chicken manure liquid fertilizer could improve tomato morphology,yield,nutrient absorption and utilization,and quality.Among the commercial organic liquid fertilizer,F4 treatment had the best yield increase effect,and its yield per plant,fruit weight and total yield were 33.03%,14.97% and 32.57% higher than that of F1,respectively.The relative profit of F4 treatment was the highest,which was 18.86% higher than that of F1.F3 treatment had the best effect on nutrient absorption and utilization of tomato,and the accumulation of N,P and K in F3 treatment increased by 55.88%,66.41% and 37.53%compared with F1,respectively.With the increase of fertilizer application rate,tomato flavor indexes such as soluble solid,titratable acid and soluble sugar increased firstly and then decreased,and F4 treatment was superior.The yield per plant,fruit weight and total yield of G4 were the highest in self-made chicken manure liquid machine fertilizer G,which were increased by 27.27%,10.16% and 27.41% compared with that without fertilization,respectively,and the relative profit was the highest at this time,which was increased by19.85% compared with that without fertilization.The accumulation of N,P and K in G5 was the highest,which increased 39.42%,32.92% and 30.78% compared with G1,respectively.With the increase of fertilizer application rate,soluble solid,titratable acid,soluble sugar and other flavor indexes of tomato increased first and then decreased,among which G5 treatment had the best effect on improving tomato quality.2.Influence on soil fertility.Application of liquid organic fertilizer can reduce soil bulk density and soil p H,increase soil organic matter content,soil nutrient content and soil C/N ratio.With the increase of fertilizer application rate,the soil bulk density and soil p H of F and G treatments decreased gradually.Soil organic matter,soil nutrients and soil C/N ratio were gradually increased.Soil C/N ratio increased gradually with the change of growth stage,and F treatment F6 was the highest at maturity stage,which increased by 18.40% compared with F1 treatment.G treatment G5 was the highest,which increased by 13.10% compared with G1.The content of available p in soil decreased firstly and then tended to be stable with the growth stage.The content of F6 in F treatment was the highest,which increased by 21.77%compared with that in F1.G treatment had the highest content of G3,which increased by15.37% compared with G1.The soil available potassium increased firstly and then decreased with the change of growth stage.The content of F6 in F treatment was the highest at maturity stage,which was 32.37% higher than that in F1 treatment.G treatment had the highest CONTENT of G6,which increased by 21.41% compared with G1.3.Effects on soil enzyme activity indexes.Application of organic liquid fertilizer can increase the activities of soil urease,soil phosphatase,soil sucrase and soil catalase.The results showed that soil urease increased first and then decreased with the change of growth stage,and F6 and G6 in F and G treatments were the highest at maturity stage,which increased by18.29% and 21.71% compared with F1 and G1,respectively.Soil sucrase increased first and then decreased with the growth stage,and the difference was most significant in fruit expansion stage.Soil phosphatase increased gradually with the change of growth stage,among which,F treatment F5 was the highest at maturity stage,which increased by 25.88%compared with F1 treatment.G treatment G6 was the highest,which increased by 33.49%compared with G1.Catalase increased firstly and then tended to be stable with the change of growth stage,and there was no significant difference between different fertilizer application rates.At maturity stage,F3 under F treatment was the highest,which increased by 11.49%compared with F1.In G treatment,G4 was the highest,which increased by 12.90% compared with G1.4.Effects on soil biological indexes.The analysis of the microorganisms in the soil treated with no fertilizer and the optimal fertilizer application rate showed that the application of organic fertilizer could increase the abundance of Actinobacteriota,Chloroflexi and Firmicutes in the soil.The number of beneficial microorganisms of Arthrobacter,Bacillus and Mortierella was increased,and the number of harmful microorganisms of Wallemia was decreased,which improved the soil microbial environment and promoted the growth of plants to a certain extent.In conclusion,the application of organic liquid fertilizer can promote the growth of tomato and improve the soil environment,and the appropriate amount of organic liquid fertilizer can promote the growth and quality formation of tomato.When the application rate is 150 kg·hm^-2,tomato achieves the highest yield and economic effect,and fruit quality and flavor also have excellent performance.This study provided some theoretical support for rational application of organic liquid fertilizer under organic planting.