Transpiration and oil accumulation rates for developing oil palm fruits Elaeis guineensis Jacq.

Transpiration rates from and oil content changes in developing oil palm fruits were measured. During fruit development, transpiration rates showed a monotonic increase. The rate of increase was most rapid in the last three weeks of fruit ripening during which practically all mesocarp oil formed. The rate of oil accumulation in the fruits exhibited an exponential followed by a steady increase phase. The phases are proposed to correspond to those for oil droplet precipitation and growth, respectively. The magnitude of the transpiration stream is significant after most of the fruit non-oily solid matter appears formed and before the appearance of oil. Later on, transpiration becomes high enough to account for all the water converted into the fruit with the sugar precursors for oil production. This suggests that xylem flow occurred initially into the fruit before the phloem becomes the primary source for transpired water as oil is produced.