Oligosaccharins Used Together with Tebuconazole Enhances Resistance of Kiwifruit against Soft Rot Disease and Improves Its Yield and Quality

Abstract

Botryosphaeria dothidea is one of the most frequent pathogens of soft rot disease in kiwifruit. The aim of this study was to investigate the role of oligosaccharins used together with tebuconazole to control soft rot and their influences on kiwifruit’s disease resistance, growth and quality. The results show that tebuconazole displayed a toxicity against B. dothidea RF-1 with 0.87 mg kg−1 of EC50 value. Oligosaccharins used together with tebuconazole effectively managed soft rot with 84.83% of the field management effect by spraying tebuconazole + oligosaccharins (0.5:0.5, m/v) as a 5000-fold dilution liquid, which significantly (p < 0.01) exceeded the 72.05%, 52.59%, 62.17% and 33.52% effect of tebuconazole 2500-, oligosaccharins 2500-, tebuconazole 5000- and oligosaccharins 5000-fold liquids, respectively. Simultaneously, co-application of tebuconazole and oligosaccharins was more effective for enhancing the resistance, growth and quality of kiwifruit compared with tebuconazole or oligosaccharins alone. This work highlights that oligosaccharins used together with tebuconazole can be proposed as a practicable measure for managing kiwifruit soft rot and reducing the application of chemical synthetic fungicides.