Browse Articles

Article|28 Feb 2022|OPEN
Negative regulation of root-knot nematode parasitic behavior by root-derived volatiles of wild relatives of Cucumis metuliferus CM3
Xiaoxiao Xie1,2 ,† , Jian Ling2 ,† , Zhenchuan Mao2 , Yan Li2 , Jianlong Zhao2 , Yuhong Yang2 , Yanlin Li1 , Mingyue Liu1 and Xingfang Gu2 , , Bingyan Xie,2 ,
1College of Horticulture, Hunan Agricultural University, Changsha 410128, China
2Institute of Vegetables and Flowers, Chinese Academy of Agricultural Science, Beijing 100081, China
*Corresponding author. E-mail: guxingfang@caas.cn,xiebingyan@caas.cn
Both authors contributed equally to the study.

Horticulture Research 9,
Article number: uhac051 (2022)
doi: https://doi.org/10.1093/hr/uhac051
Views: 30

Received: 20 Oct 2021
Revised: 16 Jun 2022
Accepted: 19 Feb 2022
Published online: 28 Feb 2022

Abstract

Root-knot nematodes (RKN; Meloidogyne spp.) cause a significant decrease in the yield of cucumber crops every year. Cucumis metuliferus is an important wild germplasm that has resistance to RKN in which plant root volatiles are thought to play a role. However, the underlying molecular mechanism is unclear. To investigate it, we used the resistant C. metuliferus line CM3 and the susceptible cucumber line Xintaimici (XTMC). CM3 roots repelled Meloidogyne incognita second-stage larvae (J2s), while the roots of XTMC plants attracted the larvae. CM3 and XTMC were found to contain similar amounts of root volatiles, but many volatiles, including nine hydrocarbons, three alcohols, two aldehydes, two ketones, one ester, and one phenol, were only detected in CM3 roots. It was found that one of these, (methoxymethyl)-benzene, could repel M. incognita, while creosol and (Z)-2-penten-1-ol could attract M. incognita. Interestingly, creosol and (Z)-2-penten-1-ol effectively killed M. incognita at high concentrations. Furthermore, we found that a mixture of CM3 root volatiles increased cucumber resistance to M. incognita. The results provide insights into the interaction between the host and plant-parasitic nematodes in the soil, with some compounds possibly acting as nematode biofumigation, which can be used to manage nematodes.