Germination and Seed Vigour of Indigenous Bean (Phaseolus Vulgaris) Genotype in Nepal

SAARC J. Agric., 18(2): 67-75 (2020) DOI: https://doi.org/10.3329/sja.v18i2.51109 Research Article GERMINATION AND SEED VIGOUR OF INDIGENOUS BEAN (Phaseolus vulgaris) GENOTYPE IN NEPAL Anupam Uprety1, Bhishma Raj Dahal 2* and Bishal Shrestha3 1 Institure of Agriculture and Animal science, Tribhuvan University, Kritipur, Kathmandu 2 Faculty of Agriculture, Agriculture and Forestry University, Rampur, Chitwan 3 Principal, College of Natural Resource Management, Bardibas, Nepal, ABSTRACT Bean is an important vegetable crop of Nepal but farmers of Jumla district of Nepal are experiencing low productivity, probably due to poor germination. Keeping these points in view, a study was conducted to determine the germination and seed vigour of various indigenous beans genotype of Jumla district during February to March, 2018. The promising lines of Jumli beans namely KBL-3, KBL-2, PB0002, PB0001, KBL-1 and farm saved KBL-3 were used under study. The experiment was laid in completely randomized design (CRD) with four replications and six treatments namely T1 = KBL-3, T2 = KBL-2, T3 = PB0002, T4 = PB0001, T5 = KBL-1 and T6 = Farm-saved KBL-3. Significant differences were observed in germination percentage, speed of germination, seed vigourindex and true leaf emergence among different lines of Jumli beans .The highest germination percentage (96%), seed vigour index (1367) and speed of germination (1.763) was found in the variety of KBL-3 whereas the lowest germination percentage (69%), seed vigour index (947) and speed of germination (0.968) were found in the variety of KBL-1. Days to true leaf emergence was found shortest in the KBL-3 (23.50) and longest in the farm saved KBL-3 (30.25). KBL-3 pureline of Jumli bean was found to be highly responsive to seed germination and vigour characteristics. Thus, it would be better to suggest the indigenous bean growing farmers of Jumla district to cultivate KBL-3 for better germination and seed vigour. Keywords: Seed germination, Germination percentage, Vigour index, Pure lines INTRODUCTION Bean (Phaseolus vulgaris, Fabaceae) is an indigenous pulse and a cash crop of Jumla and Karnali Zone; mostly cultivated (in terms of area) after rice, maize, wheat, barley and millet (Bhujel et al., 2012). Local landraces of beans consist of a mixture of beans having different seed coat color, shape and size, plant morphology *Corresponding author: Received: 11.12.2019 Accepted: 13.07.2020 68 Uprety et al. and yield potential. These genotypes are being used in several ways as dal (dry split pulses), dry bean, green pod vegetable, bean flour and a medicinal crop (Neuapne et al., 2004). In addition, they are used to make bread and Dhido (a typical Nepali food). Besides its uses as fodder and green manures, farmers also considered bean as a cash-generating crop (Neupane and Vaidya, 2002). Bean is an important source of dietary protein and starch in Africa and primary staple food in various parts of the Great Lakes (Hillocks et al., 2006). In Nepal, local landraces have been named as KBL (Karnali Bean Lines) and numbers are given as KBL-1, KBL-2 and they are grouped on the basis of their colors (ARS, 2011). The promising genotypes include KBL-3, PB0001, PB0002 and PB0048 (Bhujel et al., 2012). Farmers of Jumla, Nepal are mostly growing bean in un-irrigated land and its successful establishment and yield depends on timely rainfall, particularly during germination, flowering and pod formation stages. Most of the farmers use harvested crop as a source of seed for next session crop without maintaining proper management and quality. Such seeds are not stored in appropriate environmental conditions and have low physical as well as genetic purity. These kinds of seeds are the reservoir of different seed borne diseases as well. As seed treatment is not popular, broadcasted seeds are attacked by several soil microbes, which drastically reduce seed quality, vigour and seed viability. In addition, there is no proper screening of lines of Jumli beans based on seed vigour. Under such circumstances, the crop establishment and subsequent yield is largely affected, which is one of the reasons behind low production of beans in Jumla, compared to national average (MoALD, 2017). Crop yield and resource use efficiency depend on successful plant establishment in the field (Rahman et al., 2011). To maintain the optimum plant population in the field the germination and seed vigour must be good (De Villalobos and Pelaez, 2001). But there are no relevant literatures describing about the germination and seed vigour of the indigenous beans of Nepal. Keeping these points in view, a study was conducted for comparative study of germination and seed vigour of different indigenous bean genotypes of Nepal. MATERIALS AND METHODS Varietal response of Jumli beans (Phaseolus vulgaris) to seed germination and seed vigour was conducted under High-Tech nursery, Shree Kalika Falful Nursery of Chandannath Municipality- 9, Jumla during February to March, 2018. Being organic district, farmers of Jumla apply only organic fertilizers and bio-pesticides. The samples of pureline seeds of beans were collected from Agriculture Research Station, Vijaynagar, Jumla and farmer seed was collected from bean growers around the bean block as identified by DADO (District Agriculture Development Office), Jumla. The experiment was conducted in completely randomized design (CRD). GERMINATION AND SEED VIGOUR OF INDIGENOUS BEAN 69 Treatment Details A total of 6 treatments, replicated four times, were done i.e. 5 pure lines of bean seed and 1 farmer seed were used for testing. Seed sowing Seed was soaked in normal water overnight and sown in seedling tray using coco peats as growth media; in each treatment, 25 seeds were sown. Speed of germination Twenty-five seeds of each treatment in each replication were planted for germination. Number of seedlings emerging daily was counted from days of sowing the seeds till the time germination was completed or ceased. The days to germination/emergence of each replication was noted. Also, the speed of germination or emergence (X) was computed by using the following formula given by Maguire (1962). 𝑛𝑢𝑚𝑏𝑒𝑟𝑜𝑓𝑠𝑒𝑒𝑑𝑙𝑖𝑛𝑔𝑒𝑚𝑒𝑟𝑔𝑒𝑑 𝑑𝑎𝑦𝑠𝑡𝑜𝑓𝑖𝑟𝑠𝑡𝑐𝑜𝑢𝑛𝑡 X= 𝑖𝑛𝑐𝑟𝑒𝑎𝑠𝑒𝑜𝑓𝑠𝑒𝑒𝑑𝑙𝑖𝑛𝑔𝑠𝑒𝑚𝑒𝑟𝑔𝑒𝑑𝑓𝑟𝑜𝑚𝑝𝑟𝑒𝑣𝑖𝑜𝑢𝑠𝑐𝑜𝑢𝑛𝑡 𝑑𝑎𝑦𝑠𝑡𝑜𝑓𝑖𝑛𝑎𝑙𝑐𝑜𝑢𝑛𝑡 +……. + Higher the value of X, higher is the seed vigour. Germination percentage Germination percent of seeds for each replication was computed as: Germination % = Number of seeds germinated 𝑁𝑢𝑚𝑏𝑒𝑟𝑜𝑓𝑠𝑒𝑒𝑑𝑠𝑠𝑜𝑤𝑛 Seed vigour index After the determination of Root and Shoot length, seed vigour index was determined using following formula mentioned below (Abdual-Baki and Andersen, 1973): Vigour Index= (Mean of root length + mean of shoot length) × percentage of seed germination Days to true leaf emergence The days to true leaf emergence in over 50% of sample seedling observed was noted per replication of pure line; here true leaf was considered other than cotyledons leaf. Roo (...truncated)