Abstract:

‘Jingying F1’ was used as scion and ‘Jingxin rootstock No.9’, ‘Yuyi rootstock No.1’, ‘Luqing Sturdy’ and local pumpkin seed were used as rootstocks, the most suitable rootstock-scion combination was screened. At the same time, an experiment was carried out by directly transplanting self-rooted seedlings and applying biological bacterial fertilizer to explore the effects of different rootstocks and the application of biological bacterial fertilizer on soil-borne diseases and quality of small-scale watermelons in early spring greenhouses in Dongming County. The survival rate, plant growth, fruit quality, resistance to anthracnose, wilt and other soil-borne diseases of watermelon were investigated after grafting and transplanting. The results showed that the four rootstocks could almost control the watermelon soil-borne diseases and the quality of watermelon plants was improved effectively. ‘Jingxin rootstock No.9’ and ‘Jingying F1’ were the best combination, the graft survival rate was 94%, the incidence of watermelon anthracnose and the root-knot nematodiasis were reduced 23 and 57 percent respectively and the yield reached 19350 kg/hm² and the soluble sugar content reached 10.56 Brix and no soil-borne diseases occurred after grafting compared with the self-rooted seedlings. The incidence of root-knot nematodiasis decreased significantly and the yield reached 19500-19800 kg/hm² with the soluble sugar content reaching 12.5 Brix on average after grafting with biological bacterial fertilizer. Rootstock grafting has significant effect on increasing yield and disease resistance, but will reduce watermelon sweetness. Applying bio-fertilizer is beneficial for disease resistance, growth, and flavor improvement.

Key words: small-scale watermelon, rootstock, bio-fertilizer, soil-borne disease, quality