The Status Of The Mineral Nutrition In Orchards And Its Relation With Fruit Quality In Main Apple Production Regions In China

China is the largest apple producer in the world. As people are increasingly demanding high-quality fruit, improving fruit quality is the main task of apple production in the21st century. In this study, Leaf mineral nutrients; soil nutrients in the different layers; and fruit quality traits in32apple orchards in eight province of China were monitored for2years. Based on the above, leaf and soil nutrient status and its relationship with the fruit quality were judged. The results are as follows:1. An analysis of leaf data revealed that leaf nitrogen (N) and leaf magnesium (Mg) levels were extremely high in72%and88%of the orchards, respectively. In the Bohai Gulf region,94%of the orchards showed significantly higher values than the standard. In the Loess Plateau region, most orchards are lack of leave Phosphorus (P), but showed higher values than the standard of Calcium (Ca). Leaf Potassium (K) levels were lack in most orchards of China.63%of orchards in Jiaodong Peninsula and28%of orchards in the Loess Plateau region were lack of leave Iron (Fe). Copper (Cu) and Manganese (Mn) were excess in Shandong orchards, leave (B) were excess in nearly semi orchards.2. An analysis of soil data revealed that the soil pH values of the orchards in eastern China were acidic, particularly in the orchards in the Jiaodong and Liaodong peninsulas, the pH range4.73to6.54, instead the pH values in the orchards of the Loess Plateau in northwestern China were higher, the pH range7.77to8.07, Soil alkali-hydrolyzable N levels in47%of the orchards were lower than the optimal level of70mg kg-1. Generally, the soil alkali-hydrolyzable N levels of orchards in the Bohai Gulf region were significantly higher than those in the Loess Plateau region. However, although the available potassium (K) in most orchards was sufficient (51.39-309.94mg kg-1), the organic matter levels were low in most orchards in China (6.22-23.32g kg-1)3. Through the correlation analysis between leaves, fruit mineral and soil nutrients, the results showed that The soil N, P, Ca, Fe were positively correlated with the leaf N, P, Ca, Fe, respectively(r=0.362、0.409、0.413、0.356), soil P, K, Ca, Zn were significantly positively correlated with fruit P, K, Ca, Zn, respectively(r=0.618、0.381、0.409、0.363), surface soil organic matter and leaf mineral N, P, Fe, B showed a significant positive correlation(r=.333、0.397、0.530、0.452), distributed that the organic matter is in the shallow surface. leaf P, leaf K, leaf Cu, leave Mn and fruit P, fruit K, fruit Cu, fruit Mn have a significant positive correlation(r=0.722、0.473、0.448、0.434).4. Leaf Ca and leaf B content is closely related to the sugar content of ripe fruit, in addition to the Loess Plateau region, leaf B was significantly positively correlated with ripe fruit sugar content in Bohai Gulf region, meanwhile, leaf Ca and leaf B were significantly positively correlated with ripe fruit sugar content in North China. In Shandong orchards, fruit sugar content decreased along with the increase of the excess degree of leaf Cu, high leaf Cu can lead to sugar content decreased, thereby reducing the apple fruit quality, it should reduce the excessive application of Bordeaux mixture. Leaf P had a significantly positive correlation with fruit hardness, organic acids, and leaf K had a significantly positive correlation with organic acids. Soil N was negatively correlated with fruit sugar, and soil P was significantly positively correlated with fruit sugar and organic acids, soil Ca, B had a significantly positive correlation with fruit sugar.Leaf N were excess in most orchards in China, but soil nitrogen level is not high, which is related to the extensive application of available N fertilizer, this is not conducive to the improvement of the fruit quality. N, P, K, Ca, Zn, B were key minerals of affecting fruit quality.