A Novel Protein Elicitor PevL1, from Verticillium Lecanii 2, Induces Systemic Resistance against Bean Aphid (Megoura Japonica Matsumura) in Phaseolus Vulgaris L

Author(s): Trinh Duy Nam, Yusuf Ali Abdulle, Khadija Javed, Tum Sokea and Dewen Qiu

Abstract

In this paper, we reported a novel protein elicitor from Verticillium lecanii (PevL1), which can induce systemic resistance against M. Japonica) in Phaseolus Vulgaris L. The protein was purified and evaluated using de novo sequencing. The PevL1 gene consists of 402 bp with a theoretical molecular weight of 14.46 kDa. The PevL1 sequence was matched to a genomic sequence (GenBank accession no. OAR00290.1). The encoded PevL1 protein was expressed in Escherichia coli, and the recombinant protein was characterized by inducing systemic resistance against M. japonica. The effects of three PevL1 concentrations (24.0, 31.0, and 50.0 µg mL−1) at different temperatures (15, 20, and 25°C) were tested under laboratory conditions. The PevL1 protein was applied to three-leaved Phaseolus Vulgaris L., and newly emerged adult bean aphids (0 to 6 h old) were released on the treated leaves. The relative expression levels of key genes of the JA and SA plant defense-related pathways were also determined by RT-qPCR. The treated plants with PevL1 exhibited significant resistance to the bean aphid compared with the control plants.