Doenças e produtividade de genótipos promissores de feijão comum em Quevedo, Equador

Abstract

RESUMOAs doenças constituem o principal problema da cultura do feijão nesta parte do Equador. Portanto, este estudo teve como objetivo quantificar a intensidade das doenças foliares e radiculares e a produção em sete genótipos de feijão comum. Utilizaramse as linhagens Ser-03, Ser-08 e Ser-31, EVG-06-103, EVG-16, o genótipo crioulo Pata de paloma e a variedade INIAP-473, esta última utilizada como testemunha. Avaliaram-se a severidade da ferrugem (Uromyces appendiculatus) e a mela (Rhizoctonia solani) nos estádios fenológicos reprodutivos R7 (formação de vagens) e R8 (inicio do enchimento de vagens) e a incidência das podridões cinzenta (Macrophomina phaseolina), parda (R. solani) e vermelha (Fusarium oxysporum f. sp. phaseoli). Foram quantificados também, o número de vagens, grãos e grãos por vagem por planta, a massa de mil grãos (g) e a produtividade (kg ha -1 ). Utilizou-se um delineamento blocos completos ao acaso com sete tratamentos (genótipos) e quatro repetições. Para a comparação entre as médias dos tratamentos foi empregado o teste de Scott-Knott (p≤0,05). Os genótipos Ser-03, Ser-08, Ser-31, EVG-16 e Pata de paloma apresentaram a menor intensidade da mela e podridão parda originadas por R. solani, o maior número de vagens e grãos por planta e, inclusive, as três primeiras linhagens foram as mais produtivas. Palavras-chave: mela, Phaseolus vulgaris L., podridões radiculares, produção de grãos Diseases and productivity of genotypes promising common bean in Ecuador ABSTRACTDiseases are the main problem of the bean crop in this part of the country. Therefore, this study aimed to quantify the intensity of foliar and root diseases and production in seven genotypes of common bean. We used the lineages Ser-03, Ser-08 e Ser-31, EVG-06-103, EVG-16, the creole genotype Pata de paloma and variety INIAP-473, the latter being used as a control. Evaluated the severity of rust (Uromyces appendiculatus) and web blight (Rhizoctonia solani) in reproductive growth stages R7 (pod formation) and R8 (beginning of pod filling), and the incidence of charcoal rot (Macrophomina phaseolina), Rhizoctonia root rot (R. solani) and Fusarium wilt (Fusarium oxysporum f. sp. phaseoli). Also quantified the number of beans, grains and seeds per pod per plant, thousand grain weight (g) and productivity (kg ha -1 ). Randomized complete block design we used with seven treatments (genotypes) and four replications. To compare the treatment means was employed by Scott-Knott (p≤0.05). Genotypes Ser-03, Ser-08, Ser-31, EVG-16 and Pata de paloma had the lowest intensity of web blight and Rhizoctonia root rot caused by R. solani, the highest number of pods and seeds per plant, and including the first three lines were the most productive.

Potencial agronómico de 18 líneas de fréjol F6 en Ecuador

“…y Sclerotium rolfsii Sacc.] (Garcés-Fiallos, 2011;2013;Garcés-Fiallos & Gamarra-Yánez, 2014;Garcés-Fiallos et al, 2012). La mustia hilachosa es la más perjudicial para este cultivo, ya que puede causar daños en el rendimiento y pérdidas al productor, el que puede dejar de percibir una tonelada cuando la severidad alcanza magnitudes de 7,79% (Garcés-Fiallos, 2011), una cifra significativa al considerar el bajo rendimiento nacional.…”

Temporal progress of web blight in three common bean genotypes on the central coast of Ecuador

“…The final incidence and AUDPC of web blight were higher in INIAP 473 in 2011 and 2012. On the one hand, the differentiated response to web blight or another disease caused by R solani has already been reported in common beans 3,5 and other crops 23 . Concerning the superiority of the SER 03 and SER 08 genotypes, as they present a lower incidence and AUDPC, this is similar to that others' work reported 3,5 , in the same experimental conditions, finding a lower disease intensity in foliar and root tissues of both common bean lineages.…”

“…Furthermore, these results are similar to those observed 4 , who found similar morphological characteristics in the vegetative tissues of this phytopathogenic fungus, but in common bean seedlings with damping-off symptoms. Even in Ecuador or other countries, R. solani has been found in both underground and aerial organs 3 .…”

“…Currently, the bean area is estimated at 25253 ha with a mean yield 1 of 0.61 t ha -1 , highlighting the provinces of Los Rios, Imbabura, and Azuay, which have the largest planted area for this crop 2 . On the central Ecuadorian coast, farmers use native and introduced cultivars 3 , which are generally susceptible to different biotic-based diseases.…”

“…Web blight considerably reduces the number of nodes, pods, and grains per plant and the grain yield 4,7 . Another predominant factor is the association between web blight and root rot, caused by R. solani 3 . Diseases management in commercial cultivars and landrace bean genotypes established in this part of Ecuador is usually through fungicides 3 .…”