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This study aimed to evaluate the reaction of six grapevine rootstocks (MGT 101-14, Ritcher 110, Paulsen 1103, K 5BB, SO4, Salt creek) and two cultivars (Quebranta and Torontel) to three species of the root-knot nematode (Meloidogyne incognita, M. arenaria and M.hapla). The experiment was performed as a completely randomized design with an 8 × 3 factorial scheme and six replicates per treatment. The experimental unit in each replicate comprised a grapevine cutting planted in 3 kg bags with sterilized soil. Cuttings were inoculated with 5000 eggs + juveniles (J2) of M. incognita, M. arenaria and M. hapla. Six months after inoculation, plants were removed from the bags, and the reaction was determined by evaluating the number of galls (NG), number of nematodes per gram of root (NNGR), and reproduction factor (RF). The evaluated rootstocks, MGT 101-14, Ritcher 110, Paulsen 1103, K 5BB, SO4 and Salt Creek, were resistant to M. incognita, M. arenaria and M. hapla, except for Salt creek, which was susceptible to the latter. The Quebranta and Torontel cultivars were susceptible to the Meloidogyne species under study.

RESUMEN El pimiento (Capsicum annuum) es un cultivo importante en Perú y se ve afectado por el nematodo agallador. El objetivo de este estudio es evaluar la reacción de tres variedades de pimiento (Papri King, Papri Queen y Bell pepper cv. "Yolo Wonder") a Meloidogyne arenaria, M. incognita y M. hapla. El diseño experimental fue completamente al azar en tres variedades de pi miento y tres especies Meloidogyne spp. con seis réplicas. Los pimientos se mantuvieron en un espacio con sombra de plástico, cultivados en bolsas de polietileno con 4 kg de arena esterilizada, que se inocularon con 5000 huevos y juveniles (J2). 90 días después de la inoculación se evaluó la altura de hoja (AH), longitud de raíz (LR), peso de hoja seca (PHS), peso de raíz fresca (PRF), índice de clorofila (SPAD), índice de agallas de raíz (IG) y factor de reproducción (FR). Los resultados mostraron que todas las variedades de pimiento eran susceptibles a M. incognita, M. arenaria y M. hapla. AH, LR, PHS, PRF y SPAD indicaron una disminución en el crecimiento y desarrollo del pimiento, con la mayor reducción observada en presencia de M. incognita, seguido de M. arenaria y M. hapla.

Chenopodium album plants showing symptoms caused by root-knot nematodes were detected in the La Joya, Arequipa, Peru. Based on the morphological, esterase phenotypes, and molecular analyses of the mitochondrial DNA region between the cytochome oxidase subunit II and 16S rRNA genes (mtDNA) and species-specific characterized amplified region, the causal agent of the observed symptoms was identified as Meloidogyne incognita. Pathogenicity was confirmed by fulfilling a modified version of Koch’s postulates. To our knowledge, this is the first report of M. incognita parasitizing C. album in Peru.

Brassica nigra plants showing symptoms caused by root-knot nematodes were detected in the municipality of La Joya, Arequipa Province, Peru. Based on morphology, esterase phenotypes, and species-specific characterized amplified region (SCAR) sequence, the causal agent was identified as Meloidogyne incognita. Pathogenicity was confirmed by a modified version of Koch’s postulates. To our knowledge, this is the first report of M. incognita infecting Brassica nigra in Peru.

Brassica nigra plants showing symptoms caused by root-knot nematodes were detected in the municipality of La Joya, Arequipa Province, Peru. Based on morphology, esterase phenotypes, and species-specific characterized amplified region (SCAR) sequence, the causal agent was identified as Meloidogyne incognita. Pathogenicity was confirmed by a modified version of Koch’s postulates. To our knowledge, this is the first report of M. incognita infecting Brassica nigra in Peru.