DETERMINATION OF PHOSPHORUS STATUS ON DUKU (Lansium domesticum) SEEDLING Desi Hernita 1)*, Roedhy Poerwanto 2), Anas D Susila 2) dan Syaiful Anwar 3)
1) Jambi Assessment Institute for Agricultural Technology, Indonesia
2) Department of Agronomi and Horticulture, Bogor Agriculture University, Indonesia
3) Department of Soil Science and Land Resource, Bogor Agriculture University, Indonesia
Abstract
Symptoms of P deficiency or excessive can be seen mainly in the leaves. The sign can be detected visually and can be done by to identifying P concentration in the each condition. The study of P status was conducted in Jambi Provinces, which was apply on duku seedling that planted in sand culture. The study was conducted in randomized complete block design, with five treatments that consisted of three plants each treatment and in three replications. The treatments consisted of five P levels: 0, 50, 100, 200, and 400 ppm. The results showed that P deficiency symptoms were characterized by stunted growth of seedlings, green-brownish and lusterless discoloration, number of leaves < 4.56 and leaf P concentration < 0.09% (very low nutrient status) and 0.09 ≤- P < 0.14% (low nutrient status). Sufficienly of P concentration was characterized by normal growth, shiny green leaves, number of leaves 4.56-7.00 and leaf P concentration 0.14 ≤- P < 0.25% (medium nutrient status). Symptoms of excessive P was showed by stunted growth of seedlings, green leaves with yellow and necrotic spots on the leaf blade, number of leaves < 4.56, P concentrations in the leaf ≥- 0.25% (high and very high nutrient status). The maximum growth of duku seedling for very low nutrient status was 195 ppm P.
