Screening the Cucumber Germplasm Collection for Combining Ability for Yield

Abstract

<jats:p>Cucumber (<jats:italic>Cucumis sativus</jats:italic> L.) plant introduction (PI) accessions from the regional PI station at Ames, Iowa were evaluated in open-field production for single-harvest yield at Clinton, N.C. and Ames, Iowa. Check cultivars and experimental inbreds were also tested for comparison with the PI accessions (the three groups hereafter collectively referred to as cultigens). In order to make the evaluation more uniform for all cultigens regardless of sex expression and fruit size, all were crossed with Gy 14, a gynoecious pickling cucumber inbred used commonly in the production of commercial hybrids. The resulting 761 gynoecious hybrids were tested for early, total, and marketable yield using recommended cultural practices. Results were obtained for 725 cultigens at both locations. Significant differences were observed among cultigens for all traits evaluated. Differences between the two locations were also significant for total yield, corrected total yield, and percentage of early fruit. The interaction of cultigen and location was significant for standardized total yield and standardized corrected total yield. The highest yielding hybrids at both locations were produced using the following cultigens as male (paternal) parents: PI 422185, PI 390253, PI 175120, PI 173889, PI 267087, PI 175686, PI 178888, PI 385967, PI 458851, and PI 171601. The highest and lowest yielding paternal parents from the germplasm screening study were retested, along with check cultigens in a multiple-harvest trial at Clinton, N.C. Cultigens were evaluated directly, rather than as hybrids with Gy 14, and fruit number, fruit weight, and sex expression were recorded. Most cultigens performed as expected for the yield traits in the retest study. The exceptions were `Wautoma' and PI 339250, which were among the low and high yielders in the first test, but were ranked as medium and low, respectively, in the retest study.</jats:p>

Breeding new pickling cucumber hybrids: A. Morphological characterization and genetic studies

“…Highly significant mean performance differences were observed among all parents and hybrids for all characters which agreed with Wehner et al (2000) and . Furthermore, the obtained results proved that the Japanese cucumber was the promising parental line due to its desirable traits, growth, earliness, yield, and its components Gruetze et al, 2016).…”

“…Over 700 gynoecious cucumber hybrids were evaluated for early, total, and marketable yield. Significant differences were carefully observed among cultigens for all cultural traits accurately evaluated (Wehner et al, 2000). Furthermore, parental lines LC-1-1, GCN-20953, GCN-19533, Gyne-5, LC-15-5, and Japanese Long Green and K-75 were found superior on the basis of mean performance and general combining ability effects .…”