Soil And Leaf Nutrient Status And Its Evaluation Of Walnut Orchards In The Major Producing Areas Of Guizhou

Nutrient contents and deficiency in soil and walnut trees of walnut orchard are the important basis for scientific fertilization. The research studied the changes of walnut leaf nutrient content of J. sigillata in growth period and the suitable sampling periods of leaf nutrition diagnosis using adult and young J. sigillata as the materials, followed by analysis of soil and leaf nutrient contents, and evaluated its profit and loss situation and the correlation of 126 walnut orchard soil and leaf samples, by means of the S-shaped mixed sampling method, in Guizhou north high latitude cold region and southwest Guizhou, Guizhou high altitude area as the primary sampling sites, which can provide the scientific basis for scientific fertilization and nutrient management of the walnut orchard in Guizhou walnut producing areas. The main results of this study were exhibited as follows:1. The patterns of annual changing in J. sigillata leaf mineral elements at different ages were almost the same.The content of macro-elements showed little fluctuation, and ranked as Ca>N>K>P>Mg, the content of N,P, K showed a downward trend on the whole, while the content of Mg showed an upward trend; The content of Ca increased at first and then decreased; the content of micro-elements fluctuated largely, in the growth period of young J. sigillata, the content of the elements ranked as Fe>B>Mn>Zn>Cu, and in adult J.sigillata, it was Fe>Mn>B>Zn>Cu. The content of B and Mn inhibited an increasing trend, and Cu and Zn with an opposite trend, however, Fe manifested an up-down-up-down trend. The absorption of mineral nutrients by the leaves in different phonological periods was different. N, P, K, Zn and Cu were demanded greater in pollination flowering period, the requirement of N, P, K was large in fruit enlargement period and hardcore period. The results of this part of research showed that the nutrient elements of J. sigillata leaves were relatively stable from the end of 6 to late 7(Central Guizhou), which is recommended as suitable sampling period for the nutrition diagnosis of the leaves.2. The soil p H is suitable in the walnut orchard of Guizhou major producing areas; organic matter, and alkali solution N content of the soil are above the medium level; The soil is rich in total N, total P, exchange of Ca,Mg, available Mn and Cu; lack of available K, available B and available Fe content; lower in total K,available P and available Zn in part of the walnut orchard soil. There were 73% walnut orchard soil p H suitable for walnut growth; 88.2% walnut orchard soil organic matter content in the amount and scope of the above; plentiful in the total P and total N; total K were 22.1% were in the deficiency(extreme deficiency);10.3% walnut orchard soil alkaline hydrolysis N content appeared to lack of effective; available P content in the amount and range of more than 76.2%; the lack of available K serious lack of(extreme deficiency) accounted for 81.7%; soil elements in the amount of exchangeable Ca and Mg content were rich,exchangeable Mg was deficiency(extreme deficiency), accounted for 8.8%; available Mn and Cu the contents of trace elements were rich, but most soil available B deficiency, lack of(extreme deficiency) are peaked at99.3%, followed by available Fe and Zn deficiency(extreme deficiency) 45.2% and 28.5%. The most serious of high altitude area in southwest Guizhou walnut orchard soil nutrient deficiency, followed by high altitude cold area in northern Guizhou, high altitude cold area in northwest Guizhou, high altitude area in south Guizhou. Results the content of soil available nitrogen and available zinc in bear fruit orchard was more serious than the no fruit orchard. but the content of available potassium was less than that of the no fruit orchard.3. The leaves of walnut were lack of N, K, Ca, Mg, Fe and Zn, excess in Mn and Cu and suitable in B in the main producing areas of walnut orchard in Guizhou,Among of them, K was the most serious, accounted for about 85%; followed by Mg and Ca, accounted for 71.7% and 52.8%(extreme deficiency) respectively; N was43.3%, in the deficiency range; P were enough. In the micro-elements, Fe deficiency is the most severe(extreme deficiency), deficiency ratio was 92.1%; and then was Zn(85.8%); but, Mn and Cu element content are plentiful; B elements in leaf 95.3% content are in the appropriate range. High altitude area in southwest Guizhou walnut leaf nutrient deficiency is the most serious, followed by high altitude area in south Guizhou,high altitude cold area in northern Guizhou and high altitude cold area in northwest Guizhou. Results the content of walnut leaf K and Cu in bear fruit orchard was more serious than the no fruit orchard. but the content of leaves N elements was less than that of the no fruit orchard. Among different types of walnut, The content of N and Fe elements in the leaves of hybrid and common walnut was more serious than the J.sigillata, the content of Ca and Zn elements in the leaves of hybrid walnut was the most serious. While the contents of Mg of the lack of common walnut.4. In the major production areas of Guizhou, there were antagonistic and synergistic action between leaf nutrients and soil and leaf nutrient. Elements of the leaf nutrients showed obvious synergistic effect, such as N-K, N-Cu, K-Ca, K-Fe showed a significant synergistic effect. The elements showed significant antagonistic elements, such as N-Zn, Ca-Cu, Cu-Zn. Soil nutrients and nutrient elements in leaves showed obvious synergistic effect, Mn-organic matter, total N-Mn, Cu, Cu of total P, alkali solution N and Mn, available Mn-Mn, available Cu-Fe. Elements showed significant antagonism effect named as Zn-organic matter and total N-Ca and Zn.5. According to the conditions of soil nutrient abundance and deficiency of Guizhou walnut in the major producing areas of walnut orchard, and characteristics of growth and development, the following suggestions will be given. The suitable harvest period are in late September, and at the same time combined with soil deep fertilization, with organic manure as main fertilizer, and compound fertilizer as complementary, meanwhile increasing the proportion of the K and in the basal add Fe, Zn, B fertilizer. Guizhou walnut in the major producing areas of walnut orchard which for Guizhou northwest high altitude and cold core area of Hezhang County, Weining County, Shuicheng County, Pan County, Nayong County and southern Qianxi high altitude area Anlong county, Xingyi City, Puan County concentrated phosphorus deficient areas, increasing the proportion of phosphate fertilizer as well, for walnut orchard soil alkaline area Xing Ren county, Shuicheng County, Nayong County, Qianxi County, Meitan County, Changshun county and other places, application of a certain amount of acidic fertilizer. And on the basis of base fertilizer, proposals are put forward and annual fertilizer 3-4 times was needed for new walnut orchard in young walnut. As the bear fruit tress fertilizering2-3 times top dipping is suitable, and at the same time strengthening the management of soil and water in Anlong County, Xingyi City, Puan County, Hezhang County, Shuicheng County, Pan County, Nayong County,Qianxi County and Zunyi County.