Effect Of Fertilization On Fruit Yield And Quality Of Rabbiteye Blueberry

The five-year-old “Powder blue”, one species of Rabbiteye blueberry was as the study objects in this paper. Through Orthogonal experiment with three factors including N(100,50,100) 、 P(50,25,12.5) 、 K(100,50,25), The effect of the major chemical properties of soil, the physiological biochemical characteristics of Rabbiteye blueberry, the yield of fruit on different proportion of N, P, K and application amount was studied. The results show that:1.Through fertilizer application, the available nitrogen, total phosphorus, available phosphorus, total potassium, available potassium content in the soil were significantly improved,but the fertilizer had a little effects on soil total nitrogen content. There are positive correlation between the fertilizer rate and soil N,P,K content, but with the increase of the number of fertilizer, the soil nitrogen, phosphorus and potassium are gradually tends to a stable state and no longer increased. Application of acid fertilizer such as ammonium sulfate and potassium sulfate could improve soil acid alkali, and make the soil pH more suitable for Rabbiteye blueberry plants growing. A suitable amount of fertilizer can also increase the content of organic matter in soil.2.The fertilization treatment can significantly increase the total potassium content in the leaf of Rabbiteye blueberry, but those treatment has no significant effect on total nitrogen and total phosphorus; Also, the fertilization can effectively increase the storage of total nitrogen, total phosphorus, total potassium in the branches of Rabbiteye blueberry at the end of the year; Except F6 and F8, the other treatments improved the leaf chlorophyll content, the net photosynthetic rate, the water use efficiency and light energy utilization, but little effected on transpiration rate;Compared with CK, fertilization significantly improved the leaf SOD;In addition to the F2, F3, F4,F5 and F6, the other treatments enhance CAT enzyme activity;Except F4 and F7,other treatments effectively reduce the leaf MDA content; Except F3 and F8,other treatments significantly decreased leaf soluble sugar content, and the fertilization treatment had different effects in leaf soluble protein content, among them,soluble protein content was higher than CK and reached significant level(p<0.05) in the treatment of F3 and F4. The F8 and F1 treatment significantly reduced leaf soluble protein content(p<0.05), but other treatments had no significant(p>0.05); Fertilization increased the growth of new branch, the leaf area and the number of flower bud.3. In addition to F4 and F5, the other treatments significantly increased the yield of Rabbiteye blueberry, and had a little effects on fruit weight and fruit shape index. Combined with the intuitive analysis and diagnosis of fertilization synthesis(DRIS) available that the rabbit eye blueberry has a priority and bigger demands on N and K fertilizer,and P fertilizer has a little influence on rabbit eye blueberry yield.The anthocyanins, flavonoids, total phenol and soluble sugar content of fruit were significantly increased by the use of most of fertilizer treatments,but total phenol, soluble protein and soluble solids content were reduced. Anthocyanin and soluble sugar and titratable acid have a higher demand on N and K fertilizer, and the P fertilizer demand is low.4. Through comprehensive evaluation of multiple indexes such as Rabbiteye blueberry Growth Physiological and biochemical, yield per plant, fruit quality, this paper can get the following result: the best effect of these indexes is F8(Fertilization formula as N with 25 g/tree, P with 25 g/tree, K with 100 g/tree), and the worst effect of these indexes is F4(Fertilization formula as N with 50 g/tree, P with 50 g/tree, K with 50 g/tree). The comprehensive evaluation score of 9 fertilization schemes was from high to low: F8> F9> F3> F7> F1> F6> F5> F2> CK> F4.