Yellow Sap Contamination on Mangosteen (Garcinia mangostana L.) Fruit in Relation to Soil Calcium Contents and Plant Tissue

Abstract
Yellow sap contamination (YSC) is one of the mangosteen quality constrain in Indonesia. Calcium is the prominent nutrient that influence the incidence of yellow sap contamination. A research with objective to observe the relationship between incidence YSC and Ca availability in soil as well as plant tissue was done in ten locations in West Sumatra, Lampung and West Java provinces. Purposive random sampling method was used to determine the site locations. The plant and soil samples were collected from 10 sites and ten tree per sites. Correlation analysis was used to measure the relationship between incidence YSC and Ca content in fruit endocarp, mesocarp, peel, soil and leaf. The result showed that there was a variation of incidence YSC in site location with range of 8.7%−54.04%; 4.0−51.6%; and 17.7−78.6% for percentage of YSC in fruit flesh, segmentation and peel, respectively. Ca content in soil, endocarp, mesocarp and leaf were given significantly negative correlation toward incidence YSC in fruit flesh and segmentation. Ca content in leaf part correlates significantly to Ca availability in soil, endocarp and mesocarp. Ca content in leaf in the range of 1.40- 1.70% indicates YSC less than 10%.