Study On Comprehensive Fertilization In Processing Tomato Under Drip Irrigation With Mulch

Processing tomato is one of the special agricultural product in Xinjiang, its yield and export amountoccupied an important position in China. Drip irrigation and film mulch was widely adopted in processingtomato cultivation in Xinjiang, this system lead to high tomato yield as compare to conventional method,however, excess nutrient input especially N input is a common phenomenon, which lead to plant overflourishing growth, over canopy density, and may induce heavy pests and diseases hazard. Blossom-end rotis a common physiological disease in processing tomato productivity in Xinjiang, it mainly caused by Cadeficiency and result in yield losses and quality decline. These issues restrained sustainable developmentand nutrient efficiency in processing tomato production. This study designed four field experiments,namely, N fertilizer management patterns, rhizo-fertilization method, P or P+K as start fertilizer trial andcalcium application methods, to explore an comprehensive resolution for optimal nutrient management inprocessing tomato product. The impact on yield and quality of processing tomato and changes of N, P, Kfertilizer use efficiency were studied in different N management measures, rhizo-fertilization method andchanges in P and K fertilizer application methods. Effect of Blossom-end rot reduction and yield andquality of processing tomato under different calcium application methods was studied as well. The resultswould provide a comprehensive fertilization scheme supporting nutrition management of processing tomatoproduction. The main conclusions were as follows:（1） The trends of processing tomato dry matter and N, P and K absorption rate were similar, showedslow-fast-slow under different N management, while the maximum accumulation rate, rapid accumulationduration was differed among different N management. N application increased the maximum accumulationrate of dry matter and nutrient. Dry matter and K maximum accumulation rate showed an order astraditional fertilization> N_minrecommended fertilization> no N application, and N and P maximumaccumulation rates of conventional fertilization and N_mintreatments were similar but greater than no Napplication treatment. N application increased the rapid accumulation duration of dry matter and N, butshorten the rapid accumulation duration of P and K. Dry matter rapid accumulation duration of N_minrecommended fertilizer and conventional fertilization respectively extended2.5d,2.4d than no Napplication. N fertilizer application significantly increase dry matter accumulation, N, P, K absorption, andthe difference of N absorption between N_minrecommended fertilizer and traditional fertilizer was notsignificant. Processing tomato yield in N_minN management was slightly higher than the traditionalfertilization, and the quality of processing tomato was not affected, while N fertilizer rate was225kg/hm²in N_minbased N management, saved25%N fertilizer than traditional fertilizer. For this reason, N useefficiency and N partial factor productivity of N_minrecommended fertilizer were47.06%,32.11kg/kg,significantly greater than traditional fertilizer.（2） Rhizo-fertilization trial showed that compared with the conventional fertilization treatment,rhizo-fertilization significantly improved dry matter amount of tomato fruit and total dry matter amount, also significantly improved the number of fruit in single branch. The tomato yield increased by9.62%, buthad little impact on the quality indexes of processing tomato.（3） Compared with the conventional fertilization treatment, P fertilizer or P+K fertilizer as starter fertilizersignificantly improve the dry matter accumulation of tomato fruit, but had little impact on total dry matteraccumulation. P use efficiency and partial factor productivity were23.97%,201.86kg/kg, respectively,increased by39.2%and68.10%than traditional fertilizer. P fertilizer and P, K fertilizer as the starterfertilizer showed yield enhancement trend without statistical significance, however, it reduced the contentof lycopene significantly, and had little impact on the other quality index.（4） Different calcium sources experiment showed that both spraying calcium chloride and soil-basedcalcium nitrate application by drip irrigation system could increase fruit calcium content of processingtomato, reducing blossom-end rot occurring rate, and the effect by soil-based calcium nitrate dripapplication was superior to foliar application. Calcium nitrate application could increase hardness of tomatofruit, and tomato yield was140t/hm², significantly improved yield as compared to non-Ca applicationtreatment or calcium foliar application, the increase rate was22.8%and14.3%, respectively. Calciumnitrate application showed minor impact on tomato fruit quality while lycopene content reducedsignificantly.