Effects Of Biogas Slurry Regulation At Different Growth Stages On Tomato Growth,yield And Qualit

In order to improving tomato yield and exploring the response law of biogas slurry regulation during tomato growth and development period.In this paper,tomato was used as the research object,and the whole growth period of tomato was set into four growth stages(seedling period,flowering result period,fruit expansion period,fruit ripening period)by using biogas slurry hole irrigation method.Three biogas slurry concentrations(11.1%,14.3%,20%)were set up to study the effects of biogas slurry on growth,physiological characteristics,water use efficiency,yield and quality of greenhouse tomato under different water and fertilizer regulation.And the effects of soil nitrogen and phosphorus were explored and the following conclusions were obtained:(1)In this study,14.3% and 20% biogas slurry at seedling stage and flowering and fruiting stage were more conducive to the growth of tomato plant height and stem diameter.The leaf area of tomato was significantly regulated by the biogas slurry during the growth period.The application of 14.3% biogas slurry at the seedling stage had the greatest impact on the leaf area of tomato.The optimum concentration of biogas slurry was 20% at the flowering and fruiting stage,leaf area of tomato treated with 11.1% and 14.3% biogas slurry changed alternately.The chlorophyll a,chlorophyll b and chlorophyll(a+b)of tomato plant treated with biogas slurry increased with the increase of biogas slurry concentration,while chlorophyll(a/b)decreased.With the development of growth period,the chlorophyll content of tomato plants treated with higher concentration of biogas slurry was better than that treated with lower concentration of biogas slurry.(2)It was not appropriate to use excessive biogas slurry at seedling stage.14.3%biogas slurry concentration could meet the growth of tomato.The nutrient requirement period of tomato plant begins at flowering and fruiting stage,and the concentration of biogas slurry was positively correlated with the accumulation of dry matter in tomato plants from flowering to fruiting stage.The application of 14.3%,20% and 20% biogas slurry at seedling stage,flowering and fruiting stage and fruit enlargement stage had the most significant effect on the growth and dry matter accumulation of tomato plants(P<0.05),and the application amount of biogas slurry at fruit ripening stage needed to be further explored.(3)The control of water-marsh integration in fruit expansion stage was the most significant to tomato yield(P<0.05).The yield benefit of T9(20% biogas slurry)wasthe closest to that of chemical fertilizer treatment;the water use efficiency of tomato increased first and then decreased,reaching its maximum at fruit expansion stage.The application of biogas slurry in fruit expansion stage is the best for soluble sugar,sugar-acid ratio and firmness,and the application of biogas slurry in flowering and fruiting stage is the best for vitamin C and soluble solids.However,the titratable acid was the lowest when the biogas slurry was applied during the fruit expansion period,which indicated that the effects of applying biogas slurry at different growth stages were different for different quality indicators.(4)The order of the treatments determined by the comprehensive index evaluation under the regulation of biogas slurry during tomato growth period based on TOPSIS method is as follows.The results showed that T2,T6,T9 and T12 were the most reasonable treatment for biogas slurry in seedling stage,flowering and fruiting stage,fruit swelling stage,and fruit ripening stage,respectively.It showed that the optimum concentration of biogas slurry was 14.3%,20%,20% and 20% at seedling stage,flowering and fruiting stage,fruit swelling stage and fruit ripening stage,respectively.(5)At seedling stage,the absorption of soil nutrients by tomato plants was the smallest,and the residual of total nitrogen and total phosphorus in soil was the largest.After flowering and fruiting stage,the average content of total nitrogen and total phosphorus in 0~60cm soil layer increased with the increase of concentration.After fruit expansion stage,the absorption of nutrients by tomato plants increased,and the residual content of total nitrogen and phosphorus in soil decreased,which was similar to or even lower than the original value.The residual content of total nitrogen and total phosphorus in soil was lower than that in original soil under the integrated application of water-biogas at the ripening stage of tomato fruit.