Evaluation of Yield and Yield Attributing Characters in Pole Type of Dolichos Bean (Lablab purpureus L.)

Dolichos bean (Lablab purpureus L.) also known as Indian bean or Lablab bean, belongs to family leguminosae (2n=2x=22) is one of the important vegetable crops of Indian origin. Dolichos bean is a multipurpose crop grown for pulse, vegetable and forage crop for livestock. It is sensitive to photoperiods and both short day and long day types are available. It has high nutritive value and possess immense health benefits. The flavonoid ‘Genistein’ found in dolichos bean play a role in the prevention of cancer (Kobayashi et al., 2002) [2] . Although dolichos bean has been originated and cultivated in India since long time, the crop remained underexploited due to low productivity, photosensitivity, flowering irregularity, growth habit and the preference of consumers with respect to pod shape, pod size, pod color, pod aroma. Though wide genetic base exists for breeding programme, very little efforts or work have been made for its genetic improvement of yield and quality attributing characters. The evaluation of potentialities of the existing varieties is essential because it is the genetic diversity of the initial parent International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 8 Number 08 (2019) Journal homepage: http://www.ijcmas.com


Introduction
Dolichos bean (Lablab purpureus L.) also known as Indian bean or Lablab bean, belongs to family leguminosae (2n=2x=22) is one of the important vegetable crops of Indian origin. Dolichos bean is a multipurpose crop grown for pulse, vegetable and forage crop for livestock. It is sensitive to photoperiods and both short day and long day types are available. It has high nutritive value and possess immense health benefits. The flavonoid 'Genistein' found in dolichos bean play a role in the prevention of cancer (Kobayashi et al., 2002) [2] . Although dolichos bean has been originated and cultivated in India since long time, the crop remained underexploited due to low productivity, photosensitivity, flowering irregularity, growth habit and the preference of consumers with respect to pod shape, pod size, pod color, pod aroma. Though wide genetic base exists for breeding programme, very little efforts or work have been made for its genetic improvement of yield and quality attributing characters. The evaluation of potentialities of the existing varieties is essential because it is the genetic diversity of the initial parent Fourteen pole type dolichos bean genotypes were evaluated for seventeen characters by adopting randomized block design replicated thrice. Significant differences were recorded for all traits studied. 2016/DOLPVAR-6 was the earliest to flower in 34.27 days. 2016/DOLPVAR-5 recorded highest pod length (16.98 cm) and number of seeds pod -1 (4.67). Pod width was highest in 2016/DOLPVAR-12 (3.79 cm). Pod weight was maximum in 2016/DOLPVAR-12 (14g). Number of pods plant -1 ranged from 30.64 to 119.33, with the maximum in 2016/DOLPVAR-4. Three different pod colors (Green, Butter green and Purple) were recorded. Maximum genotypes had green pods except 2016/DOLPVAR-11 which had purple coloured pods. The genotypes 2016/DOLPVAR-9 (1185.58g), 2016/DOLPVAR-4 (1009g) and 2016/DOLPVAR-12 (905.67g) were found promising for pod yield plant -1 than other genotypes. These high yielding genotypes can serve as potentially useful parents in further breeding programme. material which helps in further crop improvement. Considering all the above mentioned facts, this experiment was conducted to evaluate the yield and yield attributing characters of 14 genotypes of pole type of dolichos bean for commercial cultivation in Odisha.

Materials and Methods
The research work was carried out at All India Co-ordinated Research Project on Vegetable Crops, Odisha University of Agriculture and Technology, Bhubaneswar, Odisha, India during Rabi season of 2018-19. The experimental material comprised of fourteen genotypes collected from different regions ( Table 1). The experiment was laid out in Randomized Block Design with three replications. Bold and healthy seeds were sown in different plots of each replication randomly on 25 th September, 2018.
All the recommended cultural practices were adopted uniformly to raise good crop stand. Five plants were selected at random from each plot to record observations on seventeen quantitative characters viz., plant height (cm), number of primary branches plant -1 , stem thickness (cm), inter nodal length (cm), average leaf area (cm 2 ), average leaf weight (g), inflorescence length (cm), fresh weight of root (g), days to 1st flowering, days to 50% flowering, pod length (cm), pod width (cm), pod weight (g), number of seeds pod -1 , pod yield plant -1 (g) and pod yield hectare -1 (q).

Leaf and pod characteristics
Morphological characters like leaf shape, leaf colour, petiole colour, pod shape, pod size, pod colours of all genotypes are given in Table 4. All the fourteen genotypes were found to be ovate in leaf shape.
Out of the 14 genotypes, 5 genotypes had leaves of light green in colour and rest had green coloured leaves. 5 genotypes had purple coloured petiole, 6 genotypes had light green petioles and 3 genotypes had green petioles. Out of 14 genotypes, pod shape was round in 7 genotypes and flat in 7 genotypes and pod size was long in 10 genotypes, medium and short in 2 genotypes each. Three different pod colours (Green, Butter green and Purple) were recorded. Maximum genotypes had green pods except 2016/DOLPVAR-11 which had purple coloured pods.
It may be concluded from the present investigation that genotype, 2016/ DOLPVAR-9, 2016/DOLPVAR-4 and 2016/DOLPVAR-12 showed significantly higher pod yield per plant. Therefore these genotypes can be used in breeding programme as high yielding genotype after having multi-locational yield trial in Odisha and may be recommended for their commercial utilization. These genotypes can also be used as donor parent for improvement in pod and yield trait in further dolichos bean improvement programmes.