Fruit Quality and Osmotic Adjustment of Four Tomato Cultivars under Drought Stress
Kamrun Nahar *
Department of Environmental Science and Management, North South University Dhaka, Bangladesh
S. M. Ullah
Department of Soil, Water and Environment, University of Dhaka, Dhaka, Bangladesh
*Author to whom correspondence should be addressed.
Abstract
A field experiment was conducted on loam soil to study the effect of drought stress on fruit quality and osmotic adjustment in four tomato cultivars in Bangladesh. The water stress treatments were imposed at 82-100% (T0), 69-85% (T1), 53-67% (T2), and 40-50% (T3) of the field capacity. Under stress, the quality of fruits was improved as a result of the synthesis of different acids like ascorbic acid, citric acid and malic acid. The response of solute accumulation in relation to water stress revealed significant increase in glucose, fructose and sucrose in fruits and proline contents in leaves, showed the conspicuous tendency of tomato plants to adjust osmotically against water stress.
An increase of 100% (glucose), 30% (fructose) 72% (sucrose) and 345% (proline) were found at T3 treatment compared with T0. The concentration of citric acid, malic acid and ascorbic acid increased with increasing water deficit in the plants. Water stress increased sugar and different acids and consequently improved the fruit quality. No physical damage due to stress was observed in fruits, which were over 90% red.
Keywords: Tomato, drought stress, Bangladesh, fruit quality, osmotic adjustment