Location: Vegetable Crops Research Unit
Title: Genetic and environmental effects on production of spontaneous tetraploids in cucumber (Cucumis sativus L.) Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: June 30, 2014
Publication Date: July 25, 2014
Citation: Ramirez-Madera, A.O., Havey, M.J., Weng, Y. 2014. Genetic and environmental effects on production of spontaneous tetraploids in cucumber (Cucumis sativus L.) [abstract]. National Association of Plant Breeders. Paper No. 51. Technical Abstract: The appearance of spontaneous tetraploid (4x) plants is a serious problem for cucumber growers and the seed industry. These plants produce unacceptable fruits with poor quality that do not meet market standards, and result in substantial losses. A higher frequency of spontaneous 4x plants has been associated with the recessive locus (zym) conditioning resistance to Zucchini Yellow Mosaic Virus (ZYMV). To test the hypothesis that production of 4x plants is associated to the zym locus, three ZYMV-R and one ZYMV-S inbred lines plus 49 recombinant inbred lines (RILs) segregating for zym will be field grown and evaluated for 4x plants, using visual characteristics (leaf, flower and fruit morphology) and flow cytometry. A second hypothesis to be tested is whether there is an environmental effect on spontaneous 4x production. Three ZYMV-R and two ZYMV-S (susceptible) lines were grown under different environments (two field and two greenhouse) in 2013 and 2014. Flow cytometry will be performed for 4x identification and ANOVAs will be used to test for the environmental effect on tetraploidy. If the frequency of 4x is similar across environments then the production of spontaneous tetraploid in cucumber is not significantly affected by the environment. Our results will provide valuable information towards the understanding of the genetic and environmental effects on spontaneous 4x cucumbers. If there is a genetic effect controlling this phenotype, cucumber industry would greatly benefit from molecular markers to: 1) make cheaper and more efficient the 4x identification process, 2) make more effective selection against 4x background in marker assisted backcrossing program, and 3) to select against the introgressed 4x trait present in current elite germplasm used in production of hybrid seed.