Multivariate Analysis and Optimum Proposals of Soil Nutrient and Leaf Nutrient with Fruit Qualities in 'Jiro' Persimmon Orchard

Objective The objective of the experiment is to provide theoretical support and obtain a technical proposal for improving the fruit quality and high-efficient cultivation, the influence of soil nutrients and leaf nutrients on fruit quality and optimum quantity of soil and leaf nutrient elements for good fruit qualities of 'Jiro' were studied.

Method The soil nutrient contents, leaf nutrient contents and fruit qualities of 'Jiro' orchards in Longyang District, Baoshan City were investigated, the methods of canonical correlation analysis and linear program and multivariate linear regression were used to screen the major soil nutrient factors and leaf nutrient factors affecting fruit qualities. The alternative optimum proposals of soil nutrients and leaf nutrients for good fruit qualities were obtained.

Result The quality of 'Jiro' persimmon fruit is comprehensive affected by various mineral elements of soil and leaves. The total phosphorus, total potassium and total magnesium content of leaf, organic matter, total nitrogen, available phosphorus, available potassium and available iron of soil are the major factors affecting fruit weight. The hardness of fruit is mainly affected by total phosphorus, total potassium, total calcium, total magnesium and total copper in leaf. And Soil organic matters have positive effects on all fruit quality indexes. Moreover, the results indicate that there is sufficient soil nutrient content but lower leaf nutrient content in 'Jiro' orchards of Baoshan City.

Conclusion The optimum proposal of soil nutrient elements content for 'Jiro' is 60 g·kg^-1 of organic matter, 2.5 g·kg^-1 of total N, 40.58~200 mg·kg^-1 of alkaline N, and 17.95~80 mg·kg^-1, 35~448.17 mg·kg^-1, 107.56~300 mg·kg^-1, 100.2~450 mg·kg^-1 of available P, K, Fe, Mn, 2.53~11 g·kg^-1, 150.1~1 000 mg·kg^-1 of exchangeable Ca, Mg. The optimum proposal of leaf nutrient elements content for 'Jiro' is 15~20.22 g·kg^-1, 1.09~2 g·kg^-1, 15.93~30 g·kg^-1, 10~40 g·kg^-1, 2~9.7 g·kg^-1, 0.05~0.2 g·kg^-1, 0.495~1.5 g·kg^-1, 1mg·kg^-1, 5~60 mg·kg^-1 of total N, P, K, Ca, Mg, Fe, Mn, Cu, Zn. Compared with the theoretical value, the local persimmon orchard should be appropriate to increase application of organic fertilizer, phosphorus and potash fertilizer, reduce application of nitrogen fertilizer, optimize the application proportion of microelement fertilizer.