Harpin induces rust disease (Phakopsora zizyphi-vulgaris) resistance on winter jujube (Ziziphus jujuba Mill. cv. Dongzao)

Abstract

Rust disease is an important factor limiting the winter jujube yield under certain conditions. Currently, chemical fungicides are the primary means to control this disease and no adequate safe control measures exist. The objective of this study was to investigate the potential to control rust on winter jujube by the application of the Harpin_Xoo protein. After winter jujube trees were treated with the Harpin_Xoo protein, the incidence of rust was significantly decreased by up to 87.1% compared with the water treated control. The levels of defence-related substances, salicylic acid (SA), and the activities of peroxidase (POD), polyphenol oxidase (POD), and phenylalanine ammonia lyase (PAL), were higher in treated than in control leaves. The most effective concentration of Harpin_Xoo was 20 μg ml^− 1. The Harpin_Xoo protein induced the systemic acquired resistance (SAR) in winter jujube and may offer a worthwhile strategy for disease control.

Keywords:

• disease resistance
• Harpin_Xoo protein
• Phakopsora zizyphi-vulgaris
• rust disease
• winter jujube
• Ziziphus jujuba

Acknowledgements

This work was supported by the Doctor Subject Foundation of Binzhou Polytechnic (Project No. bzybsjj0601). We thank Professor Jin-Sheng Wang of Nanjing Agricultural University for providing the Harpin_Xoo protein.