Interspecific hybridization to introduce useful genetic variability for pigeonpea improvement

Abstract

Pigeonpea (Cajanus cajan (L.) Millspaugh) is an important grain legume grown in tropical and subtropical regions of the world. Narrow genetic base coupled with low levels of resistance against important biotic/abiotic stresses in cultivated pigeonpea is the major constraint affecting its production and productivity globally. Wild Cajanus species
are the reservoir of many important genes including resistance/tolerance to diseases, insect-pests and drought,
and good agronomic traits and can be utilized to improve the crop cultivars, enrich variability, and broaden the
genetic base. Utilization of wild Cajanus species has
contributed for the development of cytoplasmic male
sterility (CMS) systems for pigeonpea improvement. Prebreeding populations involving promising wild Cajanus
accessions belonging to secondary and tertiary gene pools
as donors and popular pigeonpea cultivars as recipients
were developed for enriching variability for pigeonpea
improvement. Considerable variability was observed in these
populations for morpho-agronomic traits and for biotic
stresses. Two advanced backcross populations derived
from wild Cajanus species are being genotyped to identify
QTLs associated with agronomic traits for further
deployment in pigeonpea improvement programs.
Agronomically desirable and disease resistant introgression
lines have been identified and shared with breeding
programs for developing new high-yielding and climateresilient pigeonpea cultivars with a broad genetic base.