Reação de linhagens de feijão-vagem ao Meloidogyne javanica e M. paranaensis em casa-de-vegetação

Abstract

RESUMO. Nematoides formadores de galhas (Meloidogyne sp.) são responsáveis pela baixa produtividade na cultura do feijoeiro, cujas perdas, provocadas por esses patógenos, podem chegar até 90%. O presente estudo teve como objetivo avaliar o comportamento de seis linhagens de feijoeiro ('Hav 06', 'Hav 11', 'Hav 28', 'Hav 50', 'Hav 69' e 'Torino') frente ao parasitismo de M. javanica e de M. paranaensis. As linhagens foram inoculadas com 5.000 ovos e eventuais juvenis dos respectivos nematoides. O delineamento experimental foi inteiramente casualizado, com dez repetições para cada tratamento com os nematoides e dez repetições para testemunha sem inoculação. Quarenta e cinco dias após inoculação, os sistemas radiculares foram coletados, lavados e avaliados quanto à produção de ovos e estimativa do Fator de Reprodução (FR). Os resultados mostraram baixa reprodução dos nematoides nas linhagens de feijão-vagem avaliadas, e que, para M. javanica, o FR variou de 0,02 a 0,05, enquanto que, para M. paranaensis, a variação foi de 0,04 a 0,36, indicando que todas as linhagens se comportaram como resistentes, apresentando FR < 1.Palavras-chave: nematoide-de-galha, resistência, feijoeiro. ABSTRACT. Reaction of snap bean to Meloidogyne javanica and M. paranaensis in greenhouse.Root-knot nematodes (Meloidogyne sp.) are responsable for low productivity on bean culture, where the losses caused by this pathogen can reach 90%. The present study aimed to evaluate the behavior of six bean lineages ('Hav 06', 'Hav 11', 'Hav 28', 'Hav 50', 'Hav 69' and 'Torino') against the parasitism of M. javanica and M. paranaensis. The lineages were inoculated with 5,000 eggs and possible juveniles of each nematode in a completely randomized design, with 10 replications per treatment with the nematodes and 10 replications per treatment without inoculation (control). Forty-five days after inoculation, the roots systems were collected, washed and evaluated for egg production and estimated reproduction factor (RF). The results showed that, for M. javanica, the RF varied from 0.02 to 0.05, while for M. incognita the variation was from 0.04 to 0.36, showing that all snap bean genotypes were resistant, presenting a RF < 1.

Host‐Parasite Relationships in Root‐Knot Disease Caused by Meloidogyne inornata in Common Bean (Phaseolus vulgaris)

“…To M. javanica , resistance reports were made by Bonfim (), for the cultivar BRS Requinte, and by Baida et al. (), for lineages ‘Hav 06′, ‘Hav 11′, ‘Hav 28′, ‘Hav 50′, ‘Hav 69′ and ‘Torino’. However, these genotypes were not tested here.…”

“…Hereupon, in relation to M. incognita, high resistance levels (FR = 0) were reported by Alves et al (2011) for the genotype 'Preto Meia Lua', and resistance for the genotypes 'Terrinha-2 0 and 'Mulatinho'. To M. javanica, resistance reports were made by Bonfim (2013), for the cultivar BRS Requinte, and by Baida et al (2011), for lineages 'Hav 06 0 , 'Hav 11 0 , 'Hav 28 0 , 'Hav 50 0 , 'Hav 69 0 and 'Torino'. However, these genotypes were not tested here.…”

Reaction of common bean to Meloidogyne incognita race 1 and Meloidogyne javanica

“…Roots are damaged by the formation of giant cells, hyperplasia and hypertrophy of cells, leading to severe symptoms of nutritional deficiency in the shoot accompanied by a progressive decline of the plant (Ferraz & Monteiro, 1995). Baida et al (2011) showed that the average weight of roots can be significantly influenced in relation to controls non-inoculated with Meloidogyne spp., which respond to nematode attack, resulting in lower root weight.…”

“…Among the reasons for this low productivity is occurrence of diseases, especially root-knot nematodes of the genus Meloidogyne. According to Baida et al (2011), these pathogens can lead to bean yield drops of up to 90%, with predominant occurrence in high-temperature regions (Pedrosa et al, 2000).…”

“…Some of the main symptoms of nematode attack to bean crops are uneven plant growth, wilting during the hottest part of the day, and dwarfism (Ferraz & Monteiro, 1995). Other typical symptoms of nematodes affecting the physiological development of common bean are reduction in shoot and total mass of roots, smaller number of reproductive buds, pods, and seeds, with consequent drop in production (Baida et al, 2011).…”