Abstract

                                The effect of LHA at graded levels viz., 0, 10, 20, 30 and 40 kg/ha and Pyricularia oryzae inoculation on the alteration of nitrogen content (Total and amino nitrogen) of leaves of rice varieties IR 50 (Blast susceptible) and IR 20 (Moderately resistant) was studied under the pot culture condition. It was observed that LHA upto 20 kg/ha increased the content of total nitrogen levels and thereafter it gradually decreased in both the varieties tested. Pathogen inoculation also increased the native nitrogen content of leaves in both IR 50 and IR 20. Whereas, amino nitrogen content in both the varieties decreased upto 20 kg level and thereafter in increasing trend was observed. Invariably inoculation of leaves with blast pathogen decreased the content of amino nitrogen.

Key words : Nitrogen content, Humic acid, Blast Infection