Radovan Pokorný

Possibility of Bean yellow mosaic virus detection in Gladiolus plants by different methods

Serological and molecular methods were compared for the detection of Bean yellow mosaic virus (BYMV) in gladiolus plants. Plants showing mosaic symptoms were tested for the presence of BYMV using either DAS-ELISA, one step RT-PCR, real time (rt)-RT-PCR or IC-rt-RT-PCR. DAS-ELISA and one step RT-PCR were able to detect the virus in leaf samples, but not in corms or cormlets, while rt-RT-PCR and IC-rt-RT-PCR detected the virus in both leaves and corms or cormlets. Thus rt-RT-PCR and IC-rt-RT-PCR are proposed for the reliable diagnosis of BYMV in different tissues of gladiolus plants, particularly when virus-free stocks are required.

Effect of wetting period on infection of orchid flowers by Alternaria alternata and Curvularia eragrostidis

Abstract The effect of different durations of the incubation wetting period on the infection of Dendrobium flowers by two serious pathogens—Alternaria alternata (Fr.) Keissl. 1912 and Curvularia eragrostidis (Henn.) J.A. Mey. 1959—was investigated. Cut orchid flowers of the genus Dendrobium were used for the inoculation. The courses of symptom development and mycelium growth were determined. The results indicate that the infection and the subsequent development of disease on the flowers occur rapidly even if the conditions favourable for pathogen germination on the plant tissues persist for only 2 h. However, the proportion of infected flowers was significantly higher after a longer incubation period (6 h). The mycelium growth of the pathogen was also significantly influenced by the length of the incubation period.