THE EFFECT OF SODIUM HYPOCHLORITE AND ETHANOL AS SEED STERILANTS ON COWPEA INFECTED WITH COWPEA MOTTLE VIRUS

Abstract; The transmission of viruses through seed can be of considerable ecological significance for virus perpetuation and dissemination. This can also be of economic consequence for the plant as the seeds can be an efficient way by which virus diseases are disseminated in plants. An experiment was conducted to test the efficacy of Sodium hypochlorite and Ethanol at different concentrations as sterilants on cowpea seeds variety 96D-GLO infected with Cowpea Mottle Virus. The cowpea seeds were mechanically inoculated with the virus and surface sterilized at the rate of 5ml inoculum per seed with Sodium hypochlorite (0.5%, 0.75%, 1.0%), Ethanol (75%, 85%, 95%) and distilled water served as control for the experiment. The seeds were then sun dried for 1 hour before sowing into plastic buckets at the rate of 6 seeds per pot. The results indicated that Sodium hypochlorite and Ethanol at different concentrations significantly (P>0·05) reduced virus disease severity on the plants. This was manifested by increased growth parameters and significantly higher yields compared to the control. The experiment indicated that at the 10th week after planting, Ethanol (95%) had the significantly (P>0·05) lowest percentage virus disease severity (17.63%), tallest plants (59.13cm), largest number of leaves per plant (72.30) and highest weights for pods (37.17g) and seeds (36.07g). These results indicate prospects for the use of Sodium hypochlorite and Ethanol as seed sterilants in ameliorating viral disease severity on cowpea.