Gamma Irradiation - A Tool for Enhancing Storage Life of Grain Cowpea (Vigna unguiculata (L.) Walp.)

An experiment was conducted at the Department of Seed Science and Technology, College of Agriculture, Vellayani to study the influence of gamma irradiation in enhancing storage life of grain cowpea. The experiment consists of six treatments (100 Gy, 200 Gy, 300 Gy, 400 Gy, 500 Gy and control) with different doses of gamma rays. All the treatments were effective in control of pulse beetle infestation without any seed damage and consequently no weight loss compared to control with 56.333, 28.182 per cent seed damage and weight loss. The treatments showed higher germination parameters compared to control at lower doses of gamma rays. The treatment T2 (200 Gy) recorded highest seed germination percentage (84.33%). Speed of germination, seedling shoot length and seedling dry weight was highest at T2 (200Gy) with 32.13, 11.83 cm and 0.703 g. Seedling root length was highest at T1 (100 Gy) with 13.84 cm. Seedling vigour index I and II were maximum at T2 (200 Gy) with 2130.49 and 59.28. In the field experiment, progressive decrease in all morphological parameters was observed with increase in doses of beyond 200 Gy. No significant variation was observed in 100 Gy, 200 Gy and control. However, among all the gamma doses, 200 Gy (T2) recorded the least seed damage, weight loss and improvement in germination compared to control.