Evaluation of the cucumber gene pool of the VIR collection on precocity and fruiting period under the conditions of the Lower Volga region

Relevance . In connection with the annual epiphytotic development of peronosporosis ( Pseudoperonospora cubensis (Berk. and Curt.) Rostow. on cucumber and the absence varieties immune to this disease, it is advisable to create and cultivate precocious varieties and hybrids that can form the main part of the yield before the period of mass spread of the disease. In order to rationally use the cucumber gene pool long-term research of the world collection is carried out to search of sources of yield, precocity and resistance to peronosporosis. Material and methods . The studies were conducted at Volgograd Experimental Station of VIR (Volgograd province). The research material was 370 cucumber accessions from the world collection of VIR. Evaluation of accessions on a complex of signs was carried out according to methodical guidelines of VIR. Results and conclusions . Long-term study of cucumber accessions of various geographical origin showed that the duration of the interphase period "mass seedlings - the first harvest of fruits" did not differ significantly in samples of different geographical groups, most of them belong to the early ripening. It was found that the duration of the fruiting period depended on the degree of resistance of plants to peronosporosis: the higher the resistance of the variety or hybrid, the longer the fruiting period. A number of precocious, yielding hybrids and varieties, as well as samples with a long period of fruiting and relative resistance to peronosporosis, were allocated. The perspective material for the decision of separate problems in breeding of a cucumber is recommended.