Abstract

Oilpalm plantations have been established on an experimental basis in the States of Andhra Pradesh, Karnataka and Maharashtra. All the plantations are irrigated round the year by basin irrigation. In this paper, we examine the ecophysiological constraints, especially the atmospheric dryness, to the physiological performance of oil palm in these newly introduced sites. Microclimate, stomatal conductance and net photosynthesis were measured using an automated weather station, a porometer and an infrared gas analyser respectively. Results show that the stomatal conductance and maximum net photosynthetic rate of net photosynthesis never reached levels reported from ideal oil palm plantations elsewhere. Our values of maximum stomatal conducatance rarely crossed 500mmol/meter square/s when the values elsewhere were 600 to 800mmol/meter square/s. Similarly the maximum net photosynthetic rate in none of the three states crossed 12 mumol/meter square/s when this was 20-24 mumol/meter