Net melon resistance to Didymella bryoniae according to grafting and potassium levels

Abstract

survive in plant debris in the soil. This alternative was also proven by Ito et al. (4), who tested several rootstocks and concluded that Benincasa hispida was highly resistant to D. bryoniae and most recommended as rootstock for net melon.Another alternative to control diseases in plants has been mineral nutrition preparation; however, the interaction between nutrition and diseases has been scarcely studied, frequently yielding contradictory results or misinterpretations. On the other hand, the importance of nutrition on the manifestation or not of diseases is well known (13). The effect of nutrition on the intensity of diseases is known for a certain number of plants cultivated under controlled condition, but there are few studies related to the melon culture, especially the net type.This study aimed to assess net melon resistance to D. bryoniae according to grafting and potassium levels.One of the most important diseases affecting net melon (Cucumis melo var. reticulates Naud.) in protected environment is gummy stem blight or stem canker, which is caused by the fungus Didymella bryoniae (12). Chemical control has frequently shown low efficiency; however, some alternatives have been successful, such as grafting onto rootstocks of resistant melons, disinfection of pruning shears, establishment of the protected environment in places other than lowlands, crop rotation, and rational irrigation control (2, 10, 12 and 15).The use of grafting for vegetables such as pepper, tomato, eggplant, cucumber and melon cultures has allowed the solution of problems related to soil pathogens. According to and Crino et al. (3), this technique can be an alternative to control the fungus D. bryoniae, which is not considered a soil plant but can O controle químico do fungo Didymella bryoniae, agente causal da doença crestamento gomoso em meloeiro, frequentemente é ineficiente, e alternativas como enxertia e nutrição devem ser estudadas. Portaenxertos e concentrações de potássio foram testadas objetivando controlar a doença esta doença em meloeiro rendilhado, sob ambiente protegido. O híbrido de meloeiro 'Bônus II' pé-franco e enxertado em porta-enxertos melão 'Dinero' e abóbora 'Strong Tosa' foram cultivados Silva, E.S.; Palangana, F.C.; Goto, R.; Furtado, E.L.; Fernandes, D.M. Resistência de meloeiro rendilhado à Didymella bryoniae em função da enxertia e concentrações de potássio. Summa Phytopathologica, v.38, n.2, p.139-143, 2012. e inoculados pelo método de inserção de palito com discos de micélio de 7 mm do isolado de D. bryoniae Dbr 37, e o controle somente com inserção do palito. As plantas foram submetidas às concentrações de potássio 0; 62,5; 125; 187,5; 250 mg L -1 . Plantas de meloeiro 'Bônus II' enxertadas foram resistentes ao fungo e as não enxertadas suscetíveis. As concentrações de potássio não influenciaram tanto no tamanho da lesão no caule quanto na sobrevivência das plantas.Silva, E.S.; Palangana, F.C.; Goto, R.; Furtado, E.L.; Fernandes, D.M. Net melon resistance to Didymella bryoniae according to grafting an...

Reação e melhoramento do meloeiro visando resistência ao patógeno Macrophomina phaseolina

“…Por ser considerado um método menos oneroso e seguro para o ambiente, o uso de cultivares resistente ou porta-enxertos resistentes, no controle de patógenos habitantes do solo como M. phaseolina, pode ser utilizado de forma complementar a outros métodos de controle como o uso de agentes biológicos e controle cultural por meio da modificação das condições de pré e pós-plantio, prevenindo a epidemia (Michereff et al 2005;Silva et al 2012).…”

Reaction of melon genotypes to Didymella bryoniae (Fuckel) Rehm

“…However, in these studies, the authors inoculated the plants using suspensions of ≈ 5 × 10 5 conidia mL -1 , and this method has been shown little effective to cause the emergence of symptoms. Due to the low applicability of this method, the direct insertion of toothpick with colony disk containing the fungus in the plant stem and close to the cotyledons has been recommended (Ito et al, 2009;Santos et al, 2009a;Silva et al, 2012).…”

“…The latter is the causal agent of the main fungal diseases in melon (Ito et al, 2009;Silva et al, 2012) and watermelon (Santos et al, 2013) crops cultured in both open and protected environments.…”