Breeding evaluation of new gherkin cucumber lines to create F1 heterotic hybrids

Abstract

The purpose was to evaluate new bee-pollinated open ground parental lines of gherkin cucumber.
 Materials and Methods. The breeding studies (collection and breeding nurseries) were carried out in open ground at the Institute of Vegetable and Melon Growing of NAAS in 2016-2019. To obtain new forms and to create lines, we used inbreeding and individual selections in accordance with traditional breeding methods and cultivation technologies.
 Results and Discussion. Basing on experimental results and literature review, we created models of cucumber genotypes with specified parameters for the implementation of the gherkin cucumber breeding technology. The breeding based on the constructed models resulted in two gynoecious bee-pollinated open ground gherkin cucumber lines: F13I9 BD96 - 18 and F13I8 Toma - 18. The lines are early- ripening (44 days) and well-yielding (25.3–26.6 t/ha), exceeding the check cultivar (Dzherelo) by 20-30%. They are relatively resistant to downy mildew (5 points). They are noticeable for excellent palatability. Their plants form mainly female flowers. Their young fruits are cylindrical, green, and short (8 cm). The lines are intended to be used as female forms.
 Conclusions. The new lines have been included in the breeding process to create competitive heterotic gherkin cucumber hybrids. As of today, several F1 hybrid combinations have been derived from the new lines and the breeding work with them is going on. The lines have been submitted for registration to the National Center for Plant Genetic Resources of Ukraine at the Plant Production Institute named after V.Ya. Yuriev of NAAS. Certificate No. 353 dated 06/12/2019 was issued.