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Abstract
This study was conducted during the period from 2003 to 2006. The genetic materials used in the present investigation included 16 different genotypes of cucumber (Cucumis sativus L,), in addition to Beit Alpha variety. The genotypes were examined to CMV resistance by using biological, serological and molecular methods. At the cotyledon stage, the seedlings were mechanically inoculated by rubbing with virus inoculum. Disease severity was assessed visually at 14-25 days, on true leaves, after inoculation with CMV. The results revealed that six out of sixteen cucumber inbred lines (Cus 260/1980, 6-5-23-2 Kaha, 1-180-309-18-105 Dokky, 5-57-22-17 Kaha, Cus 38/1991, and 25-2-1-90 Kaha) were found to be without systemic symptoms of CMV infection and proved to be resistant to CMV when tested by DAS-ELISA and RT-PCR. The promising accessions as sources of resistance were intercrossed with leading commercial type (Beit Alpha) in half di-allel matting. Twenty one cucumber hybrids obtained from the half di-allel crossing were subjected to CMV artificial inoculation in a separate greenhouse and symptoms were visually monitored for two months. Only seven cucumber hybrids showed high level of resistance to CMV after screening and evaluation in greenhouse. The horticultural and genetically studies cleared that the best line was 5-57-22-17 Kaha and best hybrid was 5-57-22-17 Kaha X 1-180-309-18-105 DOKY. This hybrid was recommended for further evaluation as high yielding, good fruit quality and CMV resistance.