PERFORMANCES OF SUMMER LABLAB BEAN UNDER VARIED SOWING TIME

Abstract

The present study was conducted during the period from March 2013 to September 2013 at the experimental field and laboratory of Horticulture Department, Sylhet Agricultural University, Sylhet. Four photo insensitive lablab bean genotypes viz., SB002, SB003, SB008 and SB010 were evaluated at three different sowing dates of 14 March, 1 April and 17 April 2014 with a view to observe pod production potentiality during summer season under Sylhet conditions. The genotypes were differed in relation to some physico-morphological characteristics like seed color, hypocotyle color, flower color, pod color, pod size and shape etc. All the genotypes were found photo insensitive in nature since they flowered properly during summer season. Days to first flower was ranged from 43 to 50 days only for the all genotypes. The highest number of pods per plant was recorded from the genotype SB010 (207.7) while it was the lowest SB008 (112.4). The genotype SB008 had the highest individual pod weight (6.5 g). The highest pod yield per plant (1.13 kg) was recorded from the genotype SB003 which was followed by the genotype SB010 (1.07 kg/ plant). Date of sowing had significant effect on yield and yield attribute. Maximum number of pods per plant was recorded from the plants of 1 April sowing (207.0) which was followed by the plants of 14 March sowing (181.2). The highest individual pod weight was recorded from the plants grown from 17 April sowing (5.88 g). Pod yield per plant was the highest for the plants grown from 1 April sowing (1.18 kg) closely followed by 14 March sowing (1.04 kg). The highest green pod yield was recorded from 1 April (7.92 ton) followed by 14 March sowing (6.94 ton) indicating bright scope of bean production during summer season. Infestation of pod with pod borer was found for all the sowings (1.76% to 6.23%) while almost all the plants of 17 April were severely infected with virus (83% to 100%). Significant interaction was observed between genotypes and time of sowing on yield and yield attributes of lablab bean. The highest number of pod per plant was harvested from the genotype of SB010 (254.3) when grown from 1 April. The genotype SB003 produced the highest pod yield (10.22 t/ha) raised from 1 April sowing which was closely followed by the same genotype grown from 14 March sowing (8.93 t/ha).