Correlation Test of Leaf Phosphorus Nutrient with Mangosteen Production

Abstract

Leaf analysis can be used as a guide to diagnose nutritional status and as a fertilizer recommendation tool for mangosteen plant. Therefore, sampling technique of standard leaf sampled should be established accurately. Leaf age is the main important factor to estimate plant nutritional status. The best of leaf sampling is the one which has the best correlation between leaf nutrient concentration with growth and yield. Leaf nutrient concentration was investigated on the mangosteen orchard at Bogor, Tasikmalaya, and Purwakarta, West Java. Twenty relatively uniform and representative mangosteen trees had been selected, and every months leaf sample was analyzed for P concentration. Leaf samples were taken at 2 months after flush and then periodically up to 10 months. Observations were done for number of open flower, number of dropped flower, and number as well as weight of fruit per plant. While for fruit quality, analysis was done on the TSS of the flesh and the N, P, and K content of fruit parts. The results showed that leaves of 4 and 5 month ages were the best to be used as leaf samples to diagnose P status since they have the highest correlation (above 0.7) between P concentration in the leaf and fruit yield. P concentration in the leaves decreased as the age of leaves increased. Mangosteen leaves from Purwakarta contained more P than those from Tasikmalaya and Bogor. This results can be used as a guide to estimate fertilizer recommendations for mangosteen.