Screening methods and sources of resistance to rust and late leaf spot of groundnut. Information Bulletin no. 47

Abstract

Rust and late leaf spot are the most serious fungal diseases of groundnut worldwide, and can cause severe yield losses,
\nparticularly when they occur together. This Bulletin describes simple and effective field screening methods to identify
\ngenotypes with resistance to these diseases. Production of inoculum, sowing and inoculation of test genotypes, and disease
\nassessment in the field, using a 1-9 scale, are discussed. These methods were used dUring 1977-89 to evaluate ICRISAT's
\nworld collection of over 12 000 groundnut accessions. Several reliable sources of resistance to rust and/or late leaf spot
\nwere identified, and are listed here-124 lines resistant to rust, 54 lines resistant to late leaf spot, and 29 lines with
\ncombined resistance. An extensive bibliography is also presented, for those who require more detailed information on
\nspecific aspects of the diseases.