Physiological Responses and Proteomic Analysis on the Cold Stress Responses of Annual Pitaya (Hylocereus spp.) Branches

Junliang Zhou,Lijuan Wang,Yongya Mao,Tujian Xiao,Yuhua Ma,Zhuang Wang,Wenneng Wu

doi:10.1155/2021/1416925

Abstract

In this study, the physiological response of the annual branches of three varieties of pitaya (Xianmi, Fulong, and Zihonglong) in cold stress was investigated using a multivariate statistical method. Physiological change results showed that cold stress could decrease the moisture and chlorophyll contents, on the contrary, increase the relative electric conductivity, the contents of malonadehyde, soluble protein, soluble sugar, and free proline, and enhance the enzyme activities of peroxidase, superoxide dismutase, and catalase. Meanwhile, a comparative proteomic approach was also conducted to clarify the cold resistance-related proteins and pathways in annual pitaya branches. Proteomics results concluded that the cold tolerance of annual pitaya branches could be improved by modulating autophagy. Therefore, we hypothesized that an increased autophagy ability may be an important characteristic of the annual pitaya branches in response to cold stress conditions. Our results provide a good understanding of the physiological responses and molecular mechanisms of the annual pitaya branches in response to cold stress.

Highlights

Pitaya (Hylocereus spp.), a member of the family Cactaceae, is a perennial climbing cactus plant which is rich in anthocyanins, betanin, and plant albumin [1, 2]
We found that the cold resistance could decrease the moisture content in annual pitaya branches which are in accord with the previous report [35]
Our results showed that cold stress could significantly decrease the chlorophyll contents in the annual branches of the three varieties of pitaya, which are in accord with the previous reports [40, 41]

Summary

Introduction

Pitaya (Hylocereus spp.), a member of the family Cactaceae, is a perennial climbing cactus plant which is rich in anthocyanins, betanin, and plant albumin [1, 2]. Low temperature is found to be the most important environmental factor which can limit the development of pitaya production [5]. When exposed to low temperature, to adapt to the cold stress, plants require physiological response and cold resistance to survive, which is known as ‘cold acclimation’ [9]. In the past few years, significant progress in many plants, such as pitaya fruit [7], cassava [10, 11], alfalfa [12], petunia seedlings [13], castor seeds [14], rice [15], and grape [16], has been made in understanding the molecular mechanisms under cold stress

Methods

Results

Conclusion