An overview of rust (Uromyces viciae-fabae) and powdery mildew (Erysiphe polygoni DC) of pea (Pisum sativum L.)

Pea is a self-pollinating, cool season leguminous crop with a diploid chromosome number of 14. Pea is cultivated extensively and because of high protein content, pea is a crop with great significance. However, cultivation of pea gets affected by numerous biotic and abiotic stresses. Fungal diseases such as rust, powdery mildew, fusarium wilt etc. comes under the biotic stresses which are most widespread. Rust and powdery mildew cause major damage to the crop in both tropical and temperate locales of the world. Use of fungicide to control plant diseases is a good approach but excessive use of fungicide can cause environmental pollution and disasters throughout the world and can also built resistance in the pathogens. Therefore, to remove these constraints, disease resistant varieties must be used. Use of resistant varieties is a safe and efficient alternative method to control plant diseases. Breeding for rust and powdery mildew resistance has been started globally and a number of resistant sources have been identified. To introgress resistant gene into commercial varieties of pea, molecular tools must be integrated with conventional breeding techniques. Till date only one linkage map has been generated for rust resistance in pea; while for powdery mildew, three genes have been mapped. Molecular markers linked to these genes can be used in breeding programs of resistance varieties. To improve the efficiency of selection for rust and powdery mildew resistance and enhance varietal development, the integrated approach of genomic resources, effective molecular tools and high resolution phenotyping tools must be used. An overview of pea rust and powdery mildew, pathogen structure, yield losses and breeding techniques implied to control these diseases, is provided in this review article.