EXOGENOUS APPLICATION OF SALICYLIC ACID ON MITIGATION OF DROUGHT STRESS OF BRRI DHAN28

Abstract

The experiment was conducted at the research field of Sher-e-Bangla Agricultural University, Dhaka during the period from November 2017 to May, 2018 to know the effect of foliar application of salicylic acid on mitigation of drought stress of BRRI dhan28. the experiment consist of two factors with different levels of treatments viz A: T 0 = 0.0 µMm −2 SA, T 1 = 250 µMm −2 SA, T 2 = 500 µMm −2 SA, T 3 =

SA, T 4 = 1000 µMm −2 SA. B: different level of drought stress, S 0 =

control (normal irrigation), S 1 = moderate drought stress (water withheld from flowering stage to season end), S 2 =

Sever drought stress (water withheld from panicle initiation stage to season end). The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. Significant variation was recorded for data on growth, yield and yield contributing parameters. The maximum values for plant height, number of leaves hill -1 , number of tillers hill -1 , dry weight hill , leaf area index, relative water content (%), leaf membrane stability index, flag leaf chlorophyll content (µMm −2 ), thousand seed weight, number of filled grains panicle , 1000 grain weight (g), grain yield, and straw yield, biological yield, harvest index were obtained from foliar application of SA @ 750 µMm −2 ). Significant influence was remarked in terms of all parameter with different level of drought stress of BRRI dhan28. Results showed that the highest plant height, number of leaves hill -1 750 µMm -1 -1 , number of tillers hill , root dry weight plant -1 , dry weight plant -1 , leaf area index, relative water content, leaf membrane stability index, flag leaf chlorophyll content, number of filled grains panicle -1 was also obtained from normal irrigation without drought stress. The maximum grain yield was obtained from normal irrigation. The treatment normal irrigation

produced the highest straw yield, biological yield and harvest index. Interaction effect of salicylic acid and different level of drought stress was significantly influenced for all parameter measured. The maximum grain yield (12.02 g hill -1 ) was with foliar application of SA @ 750µMm −2 with normal irrigation. BRRI dhan 28 planted with drought stress at panicle initiation stage (severe drought stress) would be mitigated by the application of SA @ 750µMm

−2 . −2 -1