Chitosan Augments Tetramycin against Soft Rot in Kiwifruit and Enhances Its Improvement for Kiwifruit Growth, Quality and Aroma.

Qiuping Wang,Youhua Long,Xiaomao Wu,Yue Su,Cheng Zhang

doi:10.3390/biom11091257

Abstract

In this study, the co–application of chitosan and tetramycin against kiwifruit soft rot and its effects on the disease resistance, growth, quality and aroma of kiwifruit were investigated. The results show that chitosan could effectively enhance tetramycin against soft rot of kiwifruit with the field control efficacy of 85.33% for spraying chitosan 100 time + 0.3% tetramycin AS 5000–time dilution liquid, which was higher than 80.99% for 0.3% tetramycin AS 5000–time dilution liquid and significantly (p < 0.01) higher than 40.66% for chitosan 100–time dilution liquid. Chitosan could significantly (p < 0.05) improve the promoting effects of tetramycin on total phenolics, total flavonoids, SOD activity of kiwifruit compared to tetramycin during storage for 0–28 days and enhance the disease resistance of kiwifruit. Moreover, the co–application of chitosan and tetramycin was more effective than tetramycin or chitosan alone in enhancing fruit growth, improving fruit quality and increasing fruit aroma. This study highlights that chitosan can be used as an adjuvant to enhance tetramycin against soft rot of kiwifruit and promote tetramycin’s improvement for the single fruit volume and weight, vitamin C, soluble sugar, soluble solid, dry matter, soluble protein, titratable acidity and aroma of kiwifruit.

Highlights

Kiwifruit (Actinidia), as a typical representative of third–generation fruit, is rich in vitamin C and has high nutritional and medicinal values [1]
These results indicate that chitosan could effectively enhance the control of soft rot by tetramycin, and that they had a significant additive effect
The titratable acidity of fruits treated with chitosan + tetramycin was similar with that of chitosan, and lower than that of tetramycin. These findings indicate that chitosan + tetramycin could effectively improve kiwifruit quality, and chitosan and tetracycline had an additive effect on improving kiwifruit quality

Summary

Introduction

Kiwifruit (Actinidia), as a typical representative of third–generation fruit, is rich in vitamin C and has high nutritional and medicinal values [1]. Postharvest rot diseases caused by pathogens such as Penicillium expansum, Botryosphaeria dothidea and Phomopsis sp. Soft rot is the most serious disease of postharvest kiwifruit, which is mainly caused by B. dothidea, Phomopsis sp., Cryptosporiopsis actinidiae, Botrytis cinerea, Cylindrocarpon sp. In. Guizhou Province of Southwest China, kiwifruit soft rot caused by B. dothidea and Phomopsis sp. Seriously affects the quality and yield of kiwifruit and often causes 30–50% economic losses [10,11,12]. It is urgent and essential to develop green, effective, and economical control strategies of soft rot in kiwifruit

Methods

Results

Discussion

Conclusion