Identification of early maturing and leaf determinate growth habit type accessions of cluster bean (Cyamopsis tetragonoloba L. Taub.)

Abstract

Cluster bean (Cyamopsis tetragonoloba L. Taub.), commonly known as guar, is a member of the family Papilionaceae, cultivated in the Indian Sub-continent since time immemorial. It is a drought-hardy leguminous annual crop used variously for vegetables, forage and green manure. There is tremendous variability available in Indian cluster bean germplasm. Genetic resources with their enormous variability for different characters provide the base for the improvement of crop plants. Within genetic resources, genetic stocks are expected to play a major role in future crop improvement programmes. One promising unbranched, single-stemmed and flower determinate growth habit bearing accession IC-140784P1, developed through single plant selection at ICAR-NBPGR Regional Station Jodhpur starts flowering at 23 days after sowing and flowers 50% at 32 days after sowing. This accession does mature only 82 days after sowing. These accessions mature about 10-15 days early compared to normal existing improved cultivars, which take 90-95 days for maturity. Another accession IC 569315 has been characterized as leaf determinate (in which the stem terminates into the leaf) with alternate cluster-bearing habit. The majority of the cluster bean crop is grown under rainfed conditions in the drier parts of the country. Therefore, maturity is an important trait, especially for cluster bean.