Differential histopathological responses of pepper cultivars to Nacobbus celatus populations.

CABRERA, V.; LAX, P.; DOUCET, M.E

BOLETíN DE LA SOCIEDAD ARGENTINA DE BOTáNICA

SOCIEDAD ARGENTINA DE BOTÁNICA

Lugar: Córdoba; Año: 2024

0373-580X

Background and aims: The false-root knot nematode (Nacobbus) comprises polyphagous species, with pepper being one of the most affected crops. Due to the lack of resistant pepper genotypes, we compared the responses of different commercial cultivars to identify possible plant defence mechanisms against N. celatus.M&M: Nematodes from Río Cuarto (RC) and Lisandro Olmos (LO), provinces of Córdoba and Buenos Aires, respectively, were inoculated on pepper cultivars: California Wonder (control), Fyuco INTA, Yatasto and Fenomeno RZ (resistant to Meloidogyne spp.). Plants were grown under greenhouse and galls were analysed by histopathological studies. Results: In general, the commercial cultivars and the control showed the typical morphoanatomical alterations induced by N. celatus: gall formation, hyperplasia reactions, development of syncytia in the central cylinder and disorganisation of vascular tissues. However, certain differences were detected between populations and/or cultivars. Syncytial cells in contact with LO females showed a defence reaction by Fyuco INTA, whereas feeding sites in Fenomeno RZ did not denote high metabolic activity (LO and RC). Conclusions: All tested peppers were efficient hosts for both N. celatus populations, even the cultivar with resistance to Meloidogyne spp. The different responses observed between populations and/or hosts demonstrate the importance of considering nematodes from different geographical origins when testing plant material for tolerance and/or resistance to N. celatus. Studies of this nature are necessary since they facilitate a more in-depth understanding of the nematode-plant interaction.