Stimulatory Effect of Genetically Improved Cyanobacteria Nostoc and Hapalosiphon on the Growth and Yield of Rice in Paraquat treated Paddy Fields

By : M.P. Verma , Saumya Snehee

Page No: 55-58

Abstract
Nitrogen-fixing cyanobacteria Nostoc linckia and Hapalosiphon flagelliformis were found to have strong potentiality to serve as bio–N-fertilizers but only till the paddy fields were not treated with the herbicide paraquat which caused massive lysis and death of the cyanobacterial cells above 50 ppm doses. Their parental strains produced negligible heterocysts in urea enriched paddy fields. Algalization of the paddy fields with paraquat resistant and nitrogen as derepressed mutants of N. linckia and H. flagelliformis resulted in enhancement in growth and yield components of the Lalat variety of rice even under paraquat treated and Urea–N supplemented conditions. The mutants of N. linckia and H. flagelliformis produced heterocysts almost at their natural frequencies in urea containing rice fields, a feature exhibited by their parental strains growing in nitrogen–free states only.

Authors :
Saumya Snehee and M.P. Verma  : P.G. Department of Botany (M.U.), A.N.S College, Barh (Patna) 803213, Bihar.
 

DOI: https://doi.org/10.32381/JPSR.2019.35.01.6