Screening of cauliflower (Brassica oleracea var. botrytis L.) genotypes for resistance to the root-knot nematode (Meloidogyne incognita)

• Published in: Archiv für Phytopathologie und Pflanzenschutz Vol. 57; no. 3; pp. 237 - 259
• Main Authors: Kumar, Pardeep, Devi, Ruma, Kaur, Sukhjeet, Kalia, Anu, Dhillon, Tarsem Singh
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 07-02-2024; Taylor & Francis Ltd
• Subjects: Brassica oleracea botrytis; Cauliflowers; Economic impact; Flavonoids; Galling index; Genotypes; Infestation; Inoculation; Light microscopy; Meloidogyne incognita; microscopy; Nematodes; Optical microscopy; Pest resistance; Phenols; resistance; Root knot; Screening; susceptibility
• ISSN: 0323-5408; 1477-2906
• DOI: 10.1080/03235408.2024.2348005

The root-knot nematode (RKN) Meloidogyne spp. incurs substantial economic losses in vegetable crops. The present investigation involved glass-house-based screening performed by artificial inoculation of a set of 62 cauliflower accessions against RKN infestation. The PAUCE-292 genotype exhibited a resistant reaction to RKN infestation while genotypes PAUCE-15, PAUCE-16, PAUCE-19C and PAUCM-PI exhibited a moderately resistant reaction. Nematode inoculation reduced various growth parameters including plant height, plant weight and root length as compared to control but a higher percent reduction was recorded for the susceptible and highly susceptible genotypes. The root galling intensity was recorded to be high in susceptible and highly susceptible genotypes. The root-morphoanatomy studies on selected genotypes revealed no specific association of the studied traits with RKN reaction. But, optical microscopy revealed elaborate lignification and gall formation on RKN inoculation in susceptible PAUCM-SD3 and highly susceptible PAUCM-STAR accessions. The total phenol and flavonoid contents were maintained at significantly high levels in resistant genotype(s) in the initial 2.5-week post-inoculation of nematode juveniles. Therefore, this study provides biochemical cues on the mechanism of RKN resistance in cauliflower accessions.