Effect of sodium arsenate and gibberellic acid on proline, anthocyanin and phenol contents and agronomic triats in two varieties of rice (Oryza sativa L.)

Arsenic contamination in soils often leads to groundwater contamination and arsenic toxicity in plants, humans and animals. Plant hormones play a quantitative and qualitative role in the coordination of growth and yield in plants. In this research the effects of gibberellin and sodium arsenate in different genotypes of rice were studied. The work has been conducted as a factorial experiment based on completely randomized design with four replications in the field condition. The 29 days old seedlings from two genotype of Tarom as a local and Shiroudi as hybrid rice were treated with sodium arsenate (0, 50 and 100 &muM) and gibberellin (0 and 10 &muM). The proline content in leaves and roots, anthocyanin and phenol content in leaves, plant height, main panicle length, filled grains, empty grains, 1000 grain weight, yield, total biomass and harvesting index were measured. The results indicated that soduim arsenate had significant effect on all of the investigated parameters, so that with increasing soduim arsenate the proline content in leaves and roots, anthocyanin and phenol content in leaves, plant height, main panicle length, filled grains, 1000 grain weight, yield, total biomass and harvesting index significantly decreased and empty grains of rice increased. However, this negative impact in the genotype of Tarom was more than Shiroudi. Gibberlin treatment significantly improved all examined parameters in two genotype of rice under both 50 and 100 &muM sodium arsenate treatments, including proline content in leaves and roots, anthocyanin and phenol content in leaves, plant height, main panicle length, filled grains, 1000 grain weight, yield, total biomass and harvesting index. however, this positive impact in the genotype of Shiroudi was more than Tarom..