Seed World

Extra DNA Creates Cucumber with All-Female Flowers

Cucumber plants are not simply male or female. They can be seven different sexes, depending on a complex mix of genetic and environmental factors. Some high-yield cucumber varieties produce only female flowers, and a new study identifies the gene duplication that causes this unusual trait.
The study, led by Zhangjun Fei of the Boyce Thompson Institute at Cornell University in Ithaca, New York, and Sanwen Huang of the Chinese Academy of Agricultural Sciences in Beijing, appears May 22, 2015 in The Plant Cell.
The researchers discovered the extra DNA by screening genome sequences from a core collection of 115 different cucumber lines. They looked for changes called structural variations—large regions of the genome that are missing, added, reversed or duplicated. They generated a map of the 26,778 different structural variations that they found, some of which are associated with cucumber domestication. The analyses show that collectively, these structural variations affect more than 1,600 genes in the cucumber genome.
More information is available here: