Exogenous Application of Sucrose Promotes Postharvest Ripening of Kiwifruit

Liuying Fei,Zengyu Gan,Yongqi Fu,Xin Yuan,Chunpeng Wan,Jinyin Chen,Chuying Chen

doi:10.3390/agronomy10020245

Abstract

Sucrose is an important component of fruit flavor, but whether sucrose signaling affects the postharvest ripening process of kiwifruit is unclear. The aim of this article was to study the effect of sucrose application on postharvest kiwifruit ripening to clarify the effect of sucrose in this process. Our present study found that exogenous sucrose can promote ethylene synthesis, which increases the ethylene content during fruit ripening, thereby accelerating the ripening and softening of kiwifruit after harvest. A significantly higher expression of AcACS1 and AcACO2 was found in sucrose-treated fruits compared to that in mannitol-treated fruits. Blocking the ethylene signal significantly inhibited the sucrose-modulated expression of most selected ripening-related genes. Sucrose transport is essential for sucrose accumulation in fruits; therefore, we isolated the gene family related to sucrose transport in kiwifruit and analyzed the gene expression of its members. The results show that AcSUT1 and AcTST1 expression increased with fruit ripening and AcSUT4 expression decreased with ripening, indicating that they may have different roles in the regulation of fruit ripening. Additionally, many cis-elements associated with phytohormones and sugar responses were found in the promoter of the three genes, which suggests that they were transcriptionally regulated by sugar signal and phytohormones. This study demonstrates the effect of sucrose on postharvest ripening of kiwifruit, providing a good foundation for further research.

Highlights

When stored at room temperature, kiwifruit (Actinidia chinensis) is a typical climacteric fruit
The exogenous sucrose content of Ripening kiwifruit was detected during storage after harvest
The results show that the sucrose content gradually increased during storage and reached its highest level

Summary

Introduction

When stored at room temperature, kiwifruit (Actinidia chinensis) is a typical climacteric fruit. The ripening of fruit after harvesting is a complicated process involving a series of physiological and biochemical processes which involve sugar, acid, hormones, and other changes in metabolism. With the continuous pursuit of fruit quality and the rapid development of molecular biology and modern biotechnology, research on the physiological and molecular basic of fruit ripening has made great progress over the years. Research on the regulation of postharvest ripening of kiwifruit has focused on changes in the content of endogenous hormones during this process, the effects of ethylene and abscisic acid (ABA) [1,2,3]. The ripening and softening of kiwifruit were accelerated by ethylene and retarded by 1-MCP [4,5,6,7,8].

Objectives

Methods

Results

Conclusion