Performance analysis of bush lablab bean (Lablab purpureus (L.) sweet

Abstract

An experiment was carried out at the College of Horticulture, Kerala Agricultural University, Vellanikkara during September 2006 – May 2007 to analyze the performance of bush lablab bean (Lablab purpureus (L.) Sweet.). The major objectives of the study were to genetically catalogue the available germplasm and to study the genetic variability, divergence, heritability, genetic gain and correlation of different traits with yield. Twenty five accessions collected from different parts of the country were grown in randomized block design with three replications. The 25 accessions were catalogued based on the descriptor for lablab bean. Significant differences for all the characters viz. plant height, plant spread, number of primary branches, leaf length, leaf width, pedicel length, days to1st flowering, days to 50 per cent flowering, pod setting per cent, pod length, pod girth, pod thickness, pod weight, number of seeds pod-1, number of pods plant-1, yield plot-1, 100 seed weight, shelling per cent, crude fibre and crude protein content were noticed among the accessions.

The accession LP-26 was found to be the highest yielder (4.5 kg plot-1) coupled with high pod setting per cent (40.23) and number of pods plant-1 (227.33) during rabi. The accession LP-4 was found to be the best yielder during summer (1.15 kg plot-1) and the second best yielder (3.33 kg plot-1) coupled with second best pod setting per cent (38.00) and number of pods plant-1 (198.27) during rabi. Highest pod length (9.98 cm), pod girth (5.47 cm) and pod weight (4.61 g) was observed in the accession LP-27. Better shelling per cent (86.57) was expressed by the accession LP-7. Earliness (27.77 days) and highest number of seeds pod-1 (6.40) was shown by the accession LP-16. The qualitative characters like crude protein and crude fibre content was found to be highest in accessions LP-1 and LP-21 respectively. Highest genotypic coefficient of variation and phenotypic coefficient of variation was observed for number of pods plant-1. High heritability coupled with genetic gain was noted for all the morphological, reproductive and qualitative characters. The 25 accessions were grouped into five clusters and no parallelism between geographical distribution and genetic diversity was observed. A selection model was also formulated using these characters. Based on this the accession LP-26 (a pulse type) was identified as the best performer for rabi season and LP-4 (a vegetable type) for summer. The accession LP-4 is the second best one for rabi season.