槟榔营养特性与营养诊断方法的研究

STUDIES ON ARECANUT NUTRITIVE PECULARITY AND NUTRITIONAL DIAGNOSTIC METHODOLOGY

本文通过对海南岛西部(热作两院)、中部(屯昌)、东部(定安、琼海)正常槟榔园的土壤和叶片营养状况的调查和分析,研究海南岛不同地区正常槟榔树的营养特性和营养诊断方法。其结果表明:(1)各地区土壤类型和肥力特点虽有差异,但正常槟榔树营养状况除火山灰土壤的镁含量偏高外,其他养分含量没有地域性的变化。(2)槟榔叶片养分含量,除镁素外都存在月份间的不同变化和差异。(3)叶片不同着生部位(叶序),对叶片养分含量有一定影响,总的趋向是低部位(老叶)的氮、磷、钾含量都低于高部位,而钙含量则相反。(4)同一小叶,其不同分段养分分布不均匀,氮、钙含量叶片末端>中段>基部,钾含量则相反;磷和镁在不同叶序的小叶中分布规律不一致。(5)根据多点调查和分析结果,初步确定槟榔正常结果树养分含量的适宜范围为氮2.50—3.00%,磷0.22—0.24%,钾0.80—1.00%,钙0.40—0.55%,镁0.24—0.28%;槟榔正常幼树为氮2.50—2.70%,磷0.17—0.23%,钾0.70—0.95%,钙0.40—0.50%,镁0.18—0.24%。应用叶序间养分含量梯度,能对氮、钾做出更准确的诊断。

Areeanut(Areca catechu)nutritive characteristics and nutritional diagnostic me- thodology were studied by way of investgation and analysis of the nutritional sta- tus of the soils in normal Arccanut plantations and leaves of the crop.The inves- tigations were made in various parts of Hainan ranging from the west(typically S- CATC & SCCTC)to the middle(typically Tunchang County)and the east(typically Dingan and Qionghai County).In spite of the diversities for soil types and their fertility characters in various parts mentioned above,the contents of nutritive ele- ments for normal Arecanut plantations did not change with area,except for Vol- canic Ash soil with higher Mg.The nutrient contents except Mg element in the leaves varied with months of the year.The leaf position or leaf ranking had certain effects on the leaf nutrient contents.The general trend was lower N,P,and K contents for leaves in the lower part than those in the higher.But inverse trend was also true for Ca.Nutrient contents in different sections of one leaflet were unevenly distributed for different ntttritive elements.The general trend for N and Ca was in a descending order from the distal to the basal part but inversely for K,while P and Mg varied with leaves in different number.The moderate ranges of nutrient contents can be re- commended as,N 2.50—3.00%,P 0.22—0.24%, K 0.80—1.00%,Ca 0.40—0.55%,and Mg 0.24—0.28% for mature plants and N 2.50—2.70%,P 0.17—0.23%,K 0.70—0.95%, Ca 0.40—0.50% and Mg 0.18—0.24% for young plants.It was also discovered that the N and K contents can be more precisely diagnosed by way of nutrient content gradients with leaf arrangement.