Somaclonal variations and their applications in horticultural crops improvement
In vitro treatment of tissue cultures of two garlic cultivars with crude culture filtrates from Sclerotium cepivorium was used to select somaclonal variants with enhanced resistance to white rot disease. The crude culture filtrate had a negative effect on callus induction and growth. It also inhibited the differentiation of adventitious buds. The inhibitory effects were greater at higher culture filtrate concentration. With increase in concentration of crude pathogen culture filtrate, rate of callus induction, callus survival, relative growth rate of callus, callus differentiation and number of divided shoots per callus decreased. The inhibitory effect for all the parameters was more visible when crude pathogen culture filtrate was used at 50% concentration or more. However, the performance of disease resistant cultivar Hangzhong Red Skin was better than Gailiang (disease susceptible cultivar) at higher concentrations of crude pathogen culture filtrate. Some somaclonal lines and plantlets (predominantly from Hangzhong Red Skin) that showed resistance to Sclerotium cepivorum were obtained at 50%concentration level of crude pathogen culture filtrate.