Identifying sources of resistance to banded leaf and sheath blight of maize.

摘要

Forty maize inbred lines (Delhi Breeding Lines) were screened for resistance to banded leaf and sheath blight (BLSB) caused by Rhizoctonia solani under artificial epiphytotic condition during kharif 2005 in New Delhi, India. Observations on disease intensity were recorded 45 days after inoculation following a 1-5 rating scale (1 indicating non coalescent lesions limited to one sheath and 5 coalescent lesions covering up to ear and above or prematured death of plants) devised by Ajuha and Payak. Entries with disease rating 1.0-2.0 were classified as resistant, 2.1-4.0 as intermediate and 4.1-5.0 as susceptible. Ten were found susceptible (4.1-5.0) and thirty moderately resistant (2.1-4.0). None were found showing resistant reaction to BLSB, indicating paucity of resistant genotypes or higher virulence of the pathogen or both. Lines showing intermediate disease reaction of 2.5-3.0 score remained healthy till maturity.