Source Year: 1998

The relationship between latex yield of natural Hevea trees and climatic variables was investigated. Under humid tropical rainfed conditions in India, the latex yields of Hevea (clone RRII 105) were between 19.8 and 90.5 g pe tree per tap. The highest temprature experienced during 1, 7 or 30 days prior to tapping explained about 32, 42 and 64;respectively, of the day-to-day variabilility in latex yields. Multiple regression models to estimate latex yield on a tapping day, with different antecedent weather conditions were developed. Weekly weather conditions associated wtih best yields are: maximum temperature of 30.4 degree C, minimum temperature of 22.8 degree C, 5.9 h sunshine and 72 mm of rain. Any deviation from these meteorological conditions for up to a period of 6 months may significantly influence latex production. In general, highest temperature, sunshine duration, vapour pressured deficit and pan evaporation showed significant negative correlations with yield, irrespective of the time period considered. A significant positive association was observed between rainfall for >1 month and latex yield.