Efeito da temperatura e reação de genótipos de quiabeiro ao mofo branco

Abstract

A doença foi favorecida por temperaturas entre 15 e 20 ○ C e, de maneira geral, não foram observadas diferenças entre os isolados e influência do ferimento na ocorrência da doença. Não foram encontrados genótipos de quiabeiro resistentes ao mofo branco, pois todos apresentaram incidência superior a 30% de plantas mortas, sendo as plantas mais novas mais suscetíveis, e comprimento de lesão nos frutos ≥6,0 cm. Entretanto, diferenças de suscetibilidade entre os genótipos foram observadas em plantas de 30 e de 60 dias e podem ser informações úteis aos produtores para escolha de cultivares em clima ameno, assim como ser exploradas em programas de melhoramento.The okra plant is susceptible to several diseases that can cause losses to the farmer if not managed. This study aimed to evaluate the effect of temperature and the reaction of okra genotypes to white mold. Plants aged 30 days, inoculated in the collar region, injured or not, including two strains of Sclerotinia sclerotiorum, were maintained for two weeks at temperatures of 15, 20, 25, 30 or 35 ○ C. Fourteen okra genotypes at one and two months after emergence, as well as fruits at commercial harvest time, had their behavior evaluated for the disease. Damping-off or dead plants were evaluated, as well as the injure length in the inoculated fruits. The disease was favored Fischer, I.H.; Filetti, M.S.; Cruz, J.C.S.; Júnior Bueno, C.. Effect of temperature and reaction of okra genotypes to white mold. Summa Phytopathologica, v.40, n.1, p.49-53, 2014. Additional keywords: Abelmoschus esculentus, Sclerotinia sclerotiorum, susceptibility ABSTRACTby temperatures between 15 and 20 ○ C and, in general, no differences were observed between the isolates and the influence of the injury on the disease occurrence. There were no okra genotypes resistant to white mold, since all of them had more than 30% of incidence of dead plants; younger plants were more susceptible and the injure length in fruits was ≥ 6.0 cm. However, differences in the susceptibility between genotypes were observed for plants aged 30 and 60 days, which could constitute useful information for producers in the choice of cultivars under moderate climate and could be explored in breeding programs.O quiabeiro (Abelmoschus esculentus L.) é uma planta da família das Malváceas muito popular em regiões de clima tropical e subtropical e com características agronômicas peculiares à agricultura familiar. Possui alto valor alimentício, ciclo vegetativo rápido, fácil cultivo e alta rentabilidade e, devido as suas utilidades, tem sofrido um crescente aumento de consumo (12).A cultura do quiabeiro pode ser atacada por pragas e doenças, sendo que as doenças mais comuns são causadas por fungos. O mofo branco é causado por Sclerotinia sclerotiorum (Lib.) de Bary, um patógeno polífago que afeta pelo menos 408 espécies e 278 gêneros de plantas, inclusive o quiabeiro (2). É um patógeno comumente associado a perdas significativas de rendimento em lavouras de feijão e soja, com relatos no Brasil de perdas de 80% (18) e 100%, res...

Selection of Trichoderma spp. strains for the control of Sclerotinia sclerotiorum in soybean

“…Ideal conditions for white mold occurrence are high humidity, temperatures between 15 and 25ºC, and low light incidence (Fischer et al, 2014). The lack of one of these factors can delay or interrupt disease progress.…”

Reaction of brazilian cotton genotypes to white mold depends on pathogen aggressiveness and incubation conditions

“…There are proteomics, metabolomics and transcriptomics reports of the interactions Sclerotinia-Glycine max (L.) Merrill, Sclerotinia-Phaseolus vulgaris L., Sclerotinia-Helianthus annuus L. and Sclerotinia-Brassica napus L. (PELUFFO et al, 2010;GARG et al, 2013;OLIVEIRA et al, 2015;CAO;XU;CAI, 2016;JOSHI et al, 2016a;WU et al, 2016). Even the selection of genes and genotypes resistant to the fungus overlook cotton while including alfalfa (PRATT; ROWE, 1991), peanut (AKEM; MELOUK; SMITH, 1992), sunflower (ACHBANI;DE LABROUHE;VEAR, 1994;BALDINI et al, 2002;DAVAR et al, 2011), lentil (AKEM; BELLAR; BAYAA, 2006), peas (PORTER; HOHEISEL; COFFMAN, 2009), okra (FISCHER et al, 2014), canola (AHMADIFAR;DALIL, 2013;WU et al, 2013;JOSHI et al, 2016b), common beans (LEITE, 2014;ABREU, 2016) and soybeans (GARCIA;JULIATTI, 2012;BASTIEN;SONAH;BELZILE, 2014;JULIATTI et al, 2014;IQUIRA;HUMIRA;FRANÇOIS, 2015;CASTRO et al, 2016;WEI et al, 2017).…”