New Czech pickling cucumber hybrids - comparison of tolerance to Zucchini yellow mosaic virus (ZYMV)

Commonly grown cultivars of pickling cucumber (Cucumis sativus L.) in the Czech Republic are highly susceptible to Zucchini yellow mosaic virus (ZYMV). New hybrids are bred to achieve resistant plants. The level of tolerance to ZYMV of three Czech pickling cucumber hybrids 1/05, 9/05 and 12/05, was compared to four pickling and slicing cucumber cultivars ‘Othello’, ‘Melody F1’, ‘Dasher’ and ‘Lili’. Young plants were artificially inoculated with the Czech highly pathogenic ZYMV isolate, ZYMV-H. ELISA was used to determine the relative concentration of viral protein in leaves as the reciprocal value of the virus titer. The hybrid 1/05 showed the highest degree of tolerance to ZYMV-H. The virus concentration measured in its leaves was four times lower than in the susceptible ‘Melody F1’. Moreover, the ZYMV symptoms were mild and it had the least deformed fruit caused by ZYMV infection of all the tested hybrids. The virus concentration in leaves of hybrids 12/05 and 9/05 was half or the same as in the susceptible ‘Melody F1’, respectively. The pickling cucumber ‘Othello’ and slicing cucumber ‘Dasher’ and ‘Lili’ showed the same level of tolerance as the hybrid 12/05 did, but half than it was found in the susceptible ‘Melody F1’. ‘Lili’ is well-known for its high general pathogen resistance.Cucurbitaceae 2008. IX EUCARPIA Meeting. Avignon (France), May 21-24th, 200