Effects of High Water-Absorbing Polymer on Growth and Drought Endurance of Cashew Nut, Green Mango and Para-rubber Under Tropical Field Conditions

Abstract

Field experiments were conducted during January to May 1988 to study effects of high water-absorbing polymer (HWAP) namely ACRYHOPE on growth, nutrient uptake and drought endurance of para-rubber, (Hevea brasiliensis Muell. Arg) variety RRIM 600, cashew nut (Anacardium occidentale L.), local variety and green mango (Mangifera indica L cv. Keo-Sawei). The results obtained from trials on clayey soil in Rayong province revealed that irrigation treatments and HWAP application had no or otherwise inconsistent effects on plant dry weight, N, P concentrations in leave and drought endurance of para-rubber and cashew nut. In the Northeast sandy soils in Nakornratchasima and Burirum provinces, HWAP application help stimulated plant growth and increased total N and P uptake in leave of para-rubber, cashew nut and green mango, Except para-rubber, this was also true for the positive effect of HWAP on drought endurance of green mango and cashew nut seedlings. For cashew nut in particular, the beneficial effect of HWAP on drought endurance was very obvious. After planting, most cashew nut seedling treated with HWAP can withstand subsequent long dry spell occurred during the course of growing period studied. Thus significantly increased survival number of the plant against drought.