Effects of nano-potassium fertilizer on peach seedling growth and physiological characteristics of peach tree leaves

【Objective】The purpose of the study was to investigate the effects of nano-potassium fertilizer on the growth of peach seedlings and the physiological characteristics of adult peach tree leaves, and to provide a theoretical basis for the application of nano-fertilizers in peachtree cultivation.【Method】Using Prunus persica Batsch seedlings and Chunmei adult peach trees as test materials, the effects of nano-potassium fertilizers and three traditional fertilizers(potassium sulfate, soluble fertilizer and compound fertilizer) on seedling biomass, root morphology, photosynthetic performance, and physiological characteristics of adult tree leaves were compared.【Result】On peach seedlings, except that there was no significant difference(P>0.05, the same below) between nano-potassium fertilizer and potassium sulfate fertilizer in plant height, underground fresh weight and root morphology indicators, nano-potassium fertilizer could significantly increase plant height, stem diameter, the number of leaves, leaf surface area, dry(fresh) weight of aboveground and underground parts, and root system morphological indicators compared with other fertilizer treatments(P<0.05, the same below). Meanwhile, nano-potassium fertilizer also significantly increased the contents of chlorophyll a, chlorophyll b, total chlorophyll and the maximum quantum yield of photosystem Ⅱ(F_v/F_m) in the leaves of peach seedlings. On adult peach trees, compared with potassium sulfate fertilizer, nano-potassium fertilizer significantly increased the contents of total chlorophyll, soluble sugar, homogenate protein and proline in leaves by 30.2%, 48.6%, 40.4% and 33.6% respectively. The single fruit weight of peach fruits was significantly increased by 17.5%. The effects of soluble fertilizer and compound fertilizer on the leaves and fruits of adult peach trees were similar to those of nano-potassium fertilizer without reaching significant difference. 【Conclusion】Comprehensive considering morphological and physiological indicators, compared with traditional potassium fertilizer, nano-potassium fertilizer can promote the growth of aboveground and underground parts of peach seedlings to varing degrees, and increase the chlorophyll content and photosynthetic performance of young and adult peach tree leaves, to improve tree nutrient and fruit growth, which is expected to be popularized as a new type of fertilizer in practical production of peach in the future.