| Micro-environment regulation mode around root zone is combined with the apple orchard root features, according to local optimization to improve the root system, set up a local soil, suitable for root growth of good soil environmental measures, water, fertilizer and protect the purpose of the leaf, a root strong tree. In order to achieve saving water and fertilizer, protection of root, good quality and high yield.In order to further reveal and perfect the theoretical basis of micro-environment regulation mode, we studied the experiment in Chaoquan Town, Shandong Province from March 2012 to October 2015. twelve-year-old ‘Red Fuji' apple trees(rootstock Malus × hupehensis Rehd.) in field(116°50'E, 36°14'N) were used to study the changing of the soil physical property, soil fertility, soil enzyme activities, microbial populations and community diversity, root activity and root architecture, flower development, shoots and leaves growth status, leaf chlorophyll content, photosynthesis characteristics, fluorescence parameters, antioxidant enzyme activities and the fruit quality. The main results were as follows:(1) Micro-environment regulation mode around root zone improved the soil water content and soil fertility. Compared with the normal fertilization management, the treatment of micro-environment regulation decreased the soil bulk density, increased the soil porosity and enhanced the soil field capacity of 0-40 cm soil layer which was the root concentrated distribution layer, and improved the water content of different soil layers especially during the period of drought. The micro-environment regulation treatment increased nutrient content, had a great effect on increasing the content of organic matter, available N and rapidly available K, and still maintained a high level for three years. Meanwhile, the micro-environment regulation treatment reduced the loss of the organic nutrients to the deep, and made it more concentrated distribution in the concentrated distribution layers of apple roots. It can reduce the loss of elements and improve the utilization rate of nutrients.(2) Micro-environment regulation mode around root zone enhanced rhizosphere soil enzyme activity and optimized microorganism population and community. Compared with the normal fertilization management, the treatment of micro-environment regulation increased a number of rhizosphere enzyme activity, and the effect of increasing urease activity and invertase activity was the most obvious, and the treatment can increase the number of bacteria, fungi and actinomycetes at different levels, especially can increase the number of bacteria for about two times. On the bacterial community and diversity analysis indicated that, the treatment of micro-environment regulation's Shannon index of soil microbial community and Shannon evenness index were significantly higher than the normal fertilization management, and the Simpson index was lower than control. Micro-environment regulation mode around root zone optimized microorganism population and community and improved the relative abundance of each composition.(3) Micro-environment regulation mode around root zone improved root activity, optimized the root system configuration and distribution. The treatment of micro-environment regulation improved root activity about 29.1%-74.7%, the root density of the micro-environment regulation treatment were significantly higher than that of control, and the effect of increasing the biomass of 0-1 mm diameter root was the most obvious. The root system of Composited Soil treatment concentrated distribution at 0-20 cm soil layer, the root system of Buffer System treatment concentrated distribution at 20-40 cm soil layer. Compared with Composited Soil, the treatment of Buffer System improved the environment of the surrounding soil through the moisture absorption of the brick which further improve the effects on soil and roots. In conclusion, micro-environment regulation mode around root zone could increase soil fertility and reduce the loss of fertility by improving the local soil quality, and provide a stable nutrient supply for fruit tree to growth, improve the root activity and root biomass which can provide the underground safeguard for the good quality and high yield. Among the three treatments, the effect of the brick soil Buffer System(BS) treatment was the best.(4) Micro-environment regulation mode around root zone promoted the development of flower, leaves and improved photosynthesis capacity. The treatment of micro-environment regulation improved the pollen vitality, significantly increased pollen germination rate, compared with the control, the treatment of Buffer System increased about 45.45%, speeded up the leaf development, improved the specific leaf weight and weight of per hundred leaves, The content of leaf water, the leaves thickness and the leaf chlorophyll content, Pn, Gs and WUE of apple leaves were increased At the same time, the treatment of micro-environment regulation around roots increased PS? activity(Fv/Fm) and performance index(PIABS). But the value of Tfm was decreased, namely it increased the conversion rate of light energy into chemical energy. The Buffer System treatment can also prevent excessive growth of autumn shoots.(5) Micro-environment regulation mode around root zone delayed leaf senescence. As compared with control, both the leaf activities of SOD, POD, CAT and MDA content decreased under water storage regulation around roots. Thus, based on the experimental results, it was suggested that the treatment of micro-environment regulation improved the growth of roots, increased photosynthetic carbon assimilation and electron transport rate, and reduced significantly the generation of reactive oxygen species, which resulted in inhib ited senescence and prolonged functional period of apple leaves.(6) Micro-environment regulation mode around root zone increased storage nutrient content of branches. The two treatment of micro-environment regulation around roots significantly increased branch starch content and soluble sugar content in branches. Compared with control, the treatment of Composited Soil increased about 30.39% and 8.18%, the treatment of Buffer System increased about 67.97% and 20.20%. There was no significant difference among the soluble protein content and free amino acid content. Buffer System treatment can significantly increase branch starch content, soluble sugar content and free amino acid content, improve the storage nutrient branches, offer the growth nutrients for th e next year.(7) Micro-environment regulation mode around root zone promoted the development of fruit, improved the fruit quality. The two treatment of micro-environment regulation around roots significantly improved the fruit size and the weight of the fruit after 60 day of blooming, but had no significant effect on fruit shape index. The treatment of Composited Soil and Buffer System were significantly improved the color of the fruit, fruit hardness, soluble solid content, soluble sugar, Vc, cyanine glycosides content and water content, decreased fruit titratable acid content. The weight of single fruit of the two treatment increased about 11.37% and 27.96% than control.(8) In conclusion, comprehensive analysis of the two treatments of micro-environment regulation around roots about soil improvement, rhizosphere environment, aboveground growth, leaves senescence and the fruit quality improvement, the effect of Buffer System treatment is significantly higher than Composited Soil. |
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