| The nutritional status of fruit trees is related with the genotypes of fruit trees, age, soil nutrition, management and the growing season. The elements fruit needs are major and trace elements, and these elements play an important role in the tree physiolpgy. The nutrition diagnosis is an important means to judge the fruit tree’s nutritional status. Nutritoin diagnosis research starts in 70th in our country, so there are nomal fertilized blindly and exceedingly. These lead to bad fruit growth. But, by nutrition diagnosis, we could fertilize more suitable, meet fruit tree needs of nutrition, cut down the soil chemical pollution. So as to improve mordenize production and management, fruit quality, market competitives and increase economic and social benefits. For that, we should know much about how mineral nutrition elements distributes in fruit tree. In this study, mainly taking ’Cuiguan’ pear and’Huangguan’pear as materials, test leaf nutrition element content in different phyllotaxis, age and part. Disccusing the possibility of producing iron-zinc-rich pear by ex-root fertilization. And proposing the standard rang of leaf nutritional element content, for each of those five provinces. The major results are as follows:1. By testing N, P, K, Ca, Mg, Fe, Mn, Cu, Zn nine kinds of mineral elements’ content in leaves of different age ’Cuiguan’ pear trees, we get the results:N, P and Cu content in younger trees’ leaves are higher than that in elder trees’; while Ca is oppsite to it, elder trees get more Ca; eight year trees have the lowest K content; Mg, Mn and Zn are least in five year trees’ leaves; younger trees’ leaves have more Fe at first, but then, elder trees’ have more. In the annual orchard management, should make sure supplying adequate N, P and K. In the meantime, balance the N, K and Ca using. And adding some micronutrient fertilizer timely would be good.2. Testing and analyzing nine elements’ annual change of different organs of ’Cuiguan’ pear tree. Results showed that:(1) In the beginning of growth, content of N, P, K and Mg decline in every organ. In the middle phase, they get more first and then less down. Finally phase, they go upward. (2) In the shoots, Ca, Mn and Zn increase at first At the same phase, they decline and then rise in leaves. In the middle phase, they upward and then downward in roots. But nearly have no change both in trunks and branches. And in leaves, Ca and Mn increase and then decrease, and Zn get the opposite trend. In the last phase, they all rise in all parts. (3) Content of Fe and Cu shows a rising to peak and slashing down similarly likes normal distribution both in roots and trunks. At the beginning, Fe and Cu in branches get lower after increased. Cu content decreases in shoots. Fe go upward in leaves while Cu go downward. In the middle phase, Cu go up first and then down in branches. While declining first rising then in shoots. Both Fe and Cu get less in leaves. In the last phase, their content increase in most of parts, except Fe in roots which declines. (4) There are positive correlationships between N and P, N and Mg, N and Zn, P and Zn, Ca and Fe, Ca and Mn, Ca and Zn, Mn and Mg, Mn and Fe. That illustrate a benefit function exits among them.3. Taking eight year ’Cuiguan’ and ’Huangguan’ pear trees as materials, (1) As a whole of two varieties, with the rising of leaf position, N and P in leaves increased. While K, Ca, Mg, Fe and Mn decreased. Cu slightly lifted. And Zn and Mn had a low point in the middle and higher content in both other two sides. (2) The appropriate positions of leaf sampling for nutrition diagnosis of pear trees:N and Cu should be at the lower portion near the bottom of the shootlet. At the same time, K, Ca and Mg should be in the middle part and P, Fe, Mn, Zn and B should better be at the upper section.4. Through sampling and analyzing the’Cuiguan’pear leaf samples of Jiangsu, Zhejing, Hubei, Sichuan and Fujian Provinces. The elements obay normal distribution could be divided into 5 grades by 4 points, according to Standardized Probability Grading-SPG method. While the other elements obay skewness distribution graded by SPG method could be corrected by the average value of leaf nutritional elements in high yield orchards. Therefore, proposing the standard rang of leaf nutritional element content for each of those five provinces. Result shows that:(1) In Jiangsu Province, the normal standard range are N 2.34-2.53%, P 0.125-0.146%, K 1.21-1.80%, Ca 1.49-1.73%, Mg 0.33-0.39%, Fe 208-398 mg/kg, Mn 96-195 mg/kg, Cu 15.2-16.9 mg/kg, Zn 26.34-33.35 mg/kg.(2) In Zhejiang Province, the normal standard range are N 2.40-2.55%, P 0.160-0.190%, K 1.63-1.86%, Ca 1.43-1.50%, Mg 0.230-0.290%, Fe 158-250 mg/kg, Mn 29-182 mg/kg, Cu 10.89-11.99 mg/kg, Zn 24.2-35.0 mg/kg.(3) In Hubei Province, the normal standard range are N 2.33-2.48%, P 0.18-0.19%, K 1.54-1.77%, Ca 1.84-2.07%, Mg 0.23-0.29%, Fe 149-197 mg/kg, Mn 76.8-88.0 mg/kg, Cu 18.7-58.9 mg/kg, Zn 19.6-22.0 mg/kg.(4) In Sichuan Province, the normal standard range areN 1.57-2.55%, P 0.172-0.197%, K 0.90-1.30%, Ca 2.2-2.6%, Mg 0.20-0.28%, Fe 309-418 mg/kg, Mn 50.69-118.78 mg/kg, Cu 20.0-21.6 mg/kg, Zn 20.0-24.9 mg/kg;.(5) In Fujian Province, the normal standard range are N 2.48-2.72%, P 0.09-0.119%, K 1.69-1.90%, Ca 1.32-1.64%, Mg 0.28-0.33%, Fe 63.2-79.1 mg/kg, Mn 124-184 mg/kg, Cu 14.0-16.2 mg/kg, Zn 29.7-40.4 mg/kg.5. Testing N, P, K, Ca, Mg, Fe, Mn, Cu and Zn nine mineral nutrition elements’content change in those fruit, while spraying different concentrations of iron and zinc solutions, or in different fertilize methods such as pressure trunk injection, smearing and spraying. The result shows that,1) After spraying, the content of macroelements get the different maximum contents in peel with different concentrations. But they get merely no change in flesh, and lessen in core. The content of iron in fruits reach its peak at 0.1 %ferrous sulfate+0.2%zinc sulfate concentration, accompanying with zinc increasing; 2) Among the three different fertilize methods, pressure trunk injection makes iron content extremely lifted in peel and flesh. While N, K and Mg content decline. So, spraying iron and zinc solution during fruit development phase could increase pear iron and zinc content.. |
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