STANDARDIZATION OF HOT WATER TREATMENT IN CONTROLLING MAJOR SEED BORNE PATHOGENS OF VEGETABLES

Abstract

The experiment was conducted to standardize the hot water in controlling major seed borne pathogens of selected vegetables during the period from September 2017 to March 2018, in the central laboratory of the Department of Plant Pathology, Sher-e-Bangla Agricultural University, Dhaka-1207. Effect of dipping seed in hot water at 50 to 60 °C for 5 minutes against seed borne microflora were explored to standardize the temperature and time in controlling seed borne pathogens of bitter gourd, pumpkin, bottle gourd, cucumber, eggplant, chilli, tomato, lady´s fingers, radish and country bean seeds. The treatments were T 0 T 3 T 6 = Control, T 1 = 54 ºC for 5 minutes, T 4 = 50 ºC for 5 minutes, T 2 =56 ºC for 5 minutes, T 5 = 52 ºC for 5 minutes,

= 58 ºC for 5 minutes and

= 60 ºC for 5 minutes. Data were collected on % seed germination, % seed infection, % rotten seed and % dead seed. The experiments were conducted following Completely Randomized Design (CRD) and analyzed by computer package MSTAT-C. Significant differences were found in all the parameters. The highest seed germination in all the vegetables were recorded at the treatment where seeds were treated at 54 °C to 58°C for 5 minutes and the lowest were obtained at control. The lowest rotten seed of all the vegetables recorded in 60 °C and the highest rotten seeds obtained at T 0 (control). The highest dead seed of studied vegetables were recorded in T 6 (60 °C for 5 minutes) and the lowest were obtained at T 0 (control). The lowest infected seed of studied vegetables were recorded in treatment T 6 (60 °C for 5 minutes) and the highest infected seeds were obtained at T 0 (control). In most cases Chaetomium sp., Aspergillus spp., Penicillium spp., and Fusarium spp. etc were prevalent in the seed samples. So, hot water seed treatment with 54 °C to 58°C for 5 minutes could be suggested as safe, pollution free and environmental friendly for management of seed borne pathogens of selected vegetables.