Effect of kinetin on quality and harvest date of loquat fruit

Loquat fruit is a sweet-acid fruit and rich in natural antioxidants. However, the harvest season of loquat fruit is rather short and it has a short shelf life after harvesting. Therefore, an effective method is needed for postponing fruit harvest date in order to avoid peak sales. In our study, we investigated the effect of kinetin (Kn) treatment on fruit color, size, weight and levels of chlorophyll (Chl), total phenolics (TP), ascorbic acid (AA) and antioxidant activity in ‘Jiajiao’ loquat fruit during development. Our results showed that the Kn-treated fruit exhibited significantly greener color and significantly higher levels of Chl, TP and AA than control fruit. Meanwhile, the treatment also increased fruit size and weight and maintained significantly higher antioxidant activity as measured by the scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) compared to the control. Therefore, Kn treatment provide a new fresh-keeping technology in loquat fruit on the tree and it also can postpone harvest date and increase fruit quality and yield of loquat fruit.   Key words: Loquat, Jiajiao, kinetin, fruit quality, antioxidant activity, harvest date.