Pathogenicity of cucurbit plants to Leandria momordicae

Abstract

Leandria momordicae, the causal agent of net spot in cucurbits, is a difficult disease to control due
to the susceptibility of the host, to the poor efficiency of fungicides used in its control, and to the lack of resistant cultivars. Information on host and resistant plant species is essential for the integrated control of this disease. This study had the purpose to determine the reaction of some plant species to L. momordicae. The study was carried out from April to December of 2001, at Epagri/Experiment Station of Itajaí, Santa Catarina, Brazil. Several plant species were cultivated in greenhouse and inoculated with cucumber stems infected by L. momordicae. Both the
non-symptomatic and the symptomatic plants were inoculated again. The former were inoculated with conidia collected from cucumber and the latter with conidia obtained from isolates collected from each species. Cucurbita pepo, Bryonia cretica, Cucumis metuliferus and Sicana odorifera, which are not listed as host plants, were susceptible to L. momordicae, and should be considered as an inoculum source in disease control measures. Melothria pendula, Cucurbita maxima and Cayaponia tayuya did not present disease symptoms induced by the
pathogen in both inoculations.