MITIGATION OF SALT STRESS BY EXOGENOUS APPLICATION OF ASCORBIC ACID ON GROWTH AND YIELD OF TOMATO

Abstract

The pot experiment was conducted at the Horticulture Farm of Sher-e-Bangla Agricultural University, Dhaka during the period from November 2013 to April 2014 to study the mitigation of salt stress in tomato by exogenous application of ascorbic acid. BARI Tomato 14 was used as planting material. The two factor experiment was laid out in Randomized Completely Block Design with three replications. The factors were: Factor A: Four levels of salinity such as, (i) S 0 : 0 dS/m, (ii) S 1 : 6 dS/m, (iii) S 2 : 8 dS/m, (iv) S 3 : 10 dS/m and Factor B: Three concentration of ascorbic acid as mitigating agent of salt stress (i) A 0 : 0 mM AA, (ii) A 1 : 0.5 mM AA, (iii) A 2 : 1 mM AA respectively. The total treatment combination were 12, (3x4). At 80 DAT, the highest plant height (96.83 cm), number of leaves per plant (34.6), number of flower per plant (53.5), weight of individual fruit (80.4 g) and yield per pot (3.08 kg) were measured at control (0dS/m) and lowest value was observed at highest salinity level (10 ds/m) condition. The present result also showed that exogenous application of ascorbic acid significantly increased the growth contributing characters and yield of tomato in both saline and non-saline conditions. For treatment combination the tallest plant height (101.5 cm), highest number of fruit per plant (42.7), highest weight of individual fruit (81.1 g), yield per pot (3.12 kg) and yield per hectare (93.6 t) were produced from S 0 A 2 which was very close to control (S 0 A 0 ) , whereas the lowest value from S 3 A 0 . Finally, this result suggests that exogenous application of ascorbic acid can effectively mitigate the deleterious effect of salt stress in tomato up to a certain limit.