Efficacy of yellow gypsum application on mitigating arsenic bioavailability in groundnut and Boro-rice grown under arsenic contaminated soil.

ABSTRACT

Agricultural soils naturally enriched with Arsenic (As) represent a significant global human health risk. In the present investigation, a series of pot experiments were conducted to study the efficacy of three levels of Yellow Gypsum (YG) application on bioavailability of As to kharif groundnut followed by boro-rice grown under 17 different levels of soil As contamination for two consecutive years. The results revealed that application of YG @ 60 kg ha-1 effectuated the lowest soil As content and the highest percent decline in soil extractable As at pegging (9.42 mg kg-1 and 9.81%) and harvesting (8.81 mg kg-1 and 11.85%) in groundnut, maximum tillering (7.52 mg kg-1 and 16.95%) and harvesting (6.77 mg kg-1 and 19.85%) in boro-rice respectively. It was also observed that irrespective of its level, the extractable As content of soil decreased significantly (P < 0.05) with increasing dosage of YG. Increase in YG dose effectuated a significant (P < 0.05) increasing trend and increase in As content in soil indicated a decreasing trend of CaAs, FeAs and SAs ratios which pointed out the potentiality of YG for reducing As bio-availability in contaminated soils and thus could be a good option for mitigating the risk of As contamination in food chain.