ROLE OF ORGANIC AMENDMENTS ON MORPHOPHYSIOLOGY OF RICE UNDER ARSENIC STRESS

Abstract

Our study investigated the arsenic induced stress of morpho-physiology in rice plant and the role of organic amendments; cowdung, vermicompost, biochar to mitigate the damages. Rice seedling was grown in 18L pot with 4 arsenic treatment at 21DAT, 32DAT, 42DAT and 52DAT. Sodium Arsenate (0.5Nm, Na 2 HAsO 4 ) considered as As 1 and Sodium (meta) arsenite (0.5Mm, NaAsO 2 ) considered as As 2 and 1.5kg cow-dung, 600g vermi-compost and 500g biochar used as protectant. Plant height, leaf number, leaf area, tiller no. hill , chlorophyll content data are collected from 35DAT to 49 DAT with 7 or 15days interval. Relative water content, shoot and root fresh weight and dry weight data are recorded at 42DAT. The highest plant height was found at control condition at 35DAT, 42DAT and 49DAT. In case of As 1 at all the DAT, vermicompost shows the highest result of plant height and in As 2 condition biochar shows the highest plant height. Also these amendments increased the fresh and dry weight of shoot and root of rice plants. All parameters decreased significantly at 0.5 mM of arsenic stress. For both As 1 and As 2 treated plants combined with vermicompost and biochar shows an increasing percentage at all the yield contributing data parameters compare to As 1

and As 2 treated plant only. Our experiment concludes that rice plant under arsenic stress, vermicompost shows the better percentage of increasing result when plant expost to As 1

(0.5 mM; Sodium arsenate, Na 2 HAsO 4 ) and in case of As 2 (0.5 mM; Sodium meta arsenite, NaAsO 2 ) biochar shows an increasing result compare to all the treatments