Abstract:
A study was conducted in the Agronomy farm of the Faculty of
Agriculture, Eastern University, Sri Lanka to investigate the biochemical
responses of moisture stress clur ing the vegetatir,e, flowering, early fruiting
and fruit ripening stages of tomato (cv. KCI-1)" This experiment was
layed out in the RandomizedComplete BlockDesign with five treatments
and four replications. Moisture stress was imposed for different
treatments for a period of ,{ days per treatment dnring the above growth
stages. Moisture stress increased the proline content of tomato leaves.
An increasing trend in proline content was obsened with the age of
plants when sub.jected to moisture stress. There was a decrease in the
proline content 5-6 hours after supplying water and the values returned
to normal after 48 hours of re-rvatering. Moisture stress reduced the
chlorophylls a and b contents oftomato leaves. Plants which experienced
moisture stress during the vegetative and flowering stages showed greater
reduction in the chlorophyll content thap those ofthe other growth stages.
It was also observed that moisture stress caused higher reduction in
chlorophyll a than chlorophyll b. The reason for this reduction needs to
be investigated. There was a partial recovery in the chlorophylls a and b
contents of plants after re-watering. The rate of recovery of chlorophyll
content was faster during the vegetative stage than the flowering stage.
