Effects Of Fertilization Measures On Plant Growth And Soil Fertility For Tomato Under Continuous Cropping In Greenhouse

Continuous cropping has become a prominent problem in China.It showed that the soil fertility decline caused by unreasonable fertilization,and plant growth obstacles created by the soil quality decline.The effects of different fertilization on soil fertility and plant growth for tomato soil with outstanding continuous cropping obstacles were studied.The soil physical properties,chemical properties,yield and plant growth characters were detected in these trials.The effects of fertilization on soil fertility and plant growth were explored,and the consequences of fertilization on soil quality restoration and plant growth were clarified.The results will provide a theoretical basis for the soil restoration,and establish a sustainable and efficient production technology system for tomato production in the greenhouse.The results are as follows:I.Effects of different organic matter combination on tomato growth and soil fertility in greenhouse(1)The application of biocontrol bacteria increased root volume,average root diameter and underground biomass in T1.The acidic soil amendment,biochar,boron and calcium significantly promoted root length,root surface area and root volume,and which increased the dry and fresh weight of underground biomass.The biochar increased photosynthesis,transpiration rate,stomatal conductance,and net photosynthetic rate of tomatoes in T3 and T4.(2)Biological bacteria increased the soluble acid content of fruits in T1,while acidic soil amendment reduced the soluble acid concentration of fruits.There was no significant difference in fruit quality between T3 and CK,but T4 significantly reduced the Vc,soluble sugar and acid ratio of fruits.The difference for fruits yield was not be found among treatments.(3)The acidic soil amendment significantly increased soil organic matter and the available potassium concentration by 26.36%and 21.67%in T2 respectively.The biochar increased total soil nitrogen,organic matter,available nitrogen,and available potassium concentration by 24.56%,113.95%,18.92%,39.44%separately in T3,and its comprehensive fertility index was higher than acidic soil amendment.Soil fertility significantly positively correlated with total nitrogen,available nitrogen,available potassium,and organic matter,while negatively correlated with pH.Herein,biogas residue,acidic organic modifier,and biochar increased soil organic matter content,improved soil fertility and plant growth.The treatment with biochar had a higher soil organic matter content than biogas residue and acidic organic modifier.(4)The principal component analysis showed that the comprehensive score was T4>T3>T2>CK>T1,and the specific ratio of biogas residue,acidic organic modifier and biochar was 2:1:6.Based on that,the application of biocontrol bacteria was better than T3.II.Effects of bacterial microbial fertilizer and earthworm liquid fertilizer on tomato growth and soil fertility in continuous cropping in greenhouse(1)Comparing with traditional fertilizer CK,microbial fertilizerand earthworm liquid fertilizer increased the plants growth,plant biomass,and plant photosynthesis in T1 and T2.Microbial fertilizerand improves the relative growth rate of plant height and fruit yield of tomato in T1.Liquid earthworm fertilizer and microbial fertilizer significantly increased fruit soluble solids by 6.41%and reduce nitrate content by 45.740%respectively(2)Comparing with CK,T1 with microbial fertilizer and T2 with microbial fertilizer and earthworm liquid fertilizer increased soil available potassium concnetration by 25.77%and 34.02%respectively,and decreased soil pH by 3.02%and 2.63%separately.T1 increased soil organic matter and total nitrogen concentration by 37.57%and 22.44%respectively,while T2 increased soil EC by 113.92%.(3)The comprehensive fertility index SFI calculated by fertility index was T1>CK>T2.The correlation analysis showed yield had a positive correlation with SFI,organic matter,available potassium,total nitrogen,root dry weight,root fresh weight,shoot dry weight,shoot fresh weight,relative growth rate of plant height and leaf number.However,it had a negative correlation with EC,pH,available phosphorus and available nitrogen.The yield and comprehensive fertility index had a very significant positive relationship with root fresh weight and root dry weight,had a very significant negative correlation with available nitrogen,had a significant positive correlation with total nitrogen,meanwhile had no association correlation with other indices.(4)In summary,adding only microbial fertilizer was the best way to promote the growth of tomato plants and improve the soil.Adding earthworm liquid fertilizer enhanced the quality of fruit.?.Effects of different N and K ratios of nutrient elements on plant growth and soil fertility of tomato under continuous cropping in facilities(1)At the same N level,increasing K content promoted tomato plant height and root biomass,but had no significant effect on shoot biomass.The root growth,root,shoot dry and fresh weight,root nitrogen content,and shoot/root nitrogen content were all the highest in A6N10K2 8.The shoot nitrogen content were the highest in A4N12K16.(2)Based on A2N14,the increasing of K content promoted the transpiration rate and net photosynthetic rate,and photosynthesis was the highest in K(22).Based on A4N12 and A6N10,the transpiration rate showed decreased first and then increased with the increasing of K content.The transpiration rate was lowest when K content was 22%.The photosynthetic rate was the highest when K was 28%.The intercellular CO2 concentration decreased with the increasing of K content.(3)Based on A6N10,the tomato fruit quality was higher than other treatments.The Vc content was the highest in A6N10K16,meanwhile nitrate content was the lowest,and soluble sugar and soluble solids content were the highest in A6N10K28.There was no significant difference in organic acid content,sugar and acid among treatments.The single fruit weight and yield were significantly higher in A6N10K22 than other treatments,followed by A4N12K16.(4)There was no significant difference in total nitrogen,organic matter,available nitrogen,ammonium nitrogen and nitrate nitrogen among different forms of N and K content,EC increased with the increasing of K content.(5)Based on the principal component and membership function comprehensive analysis,the results showed that the effect of promoting tomato growth and improving soil fertility was the best in A4N12K16,followed by A2N14K28 and A6N10K22.