U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.


Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Main content area

Asynchronous meiosis in Cucumis hystrix–cucumber synthetic tetraploids resulting in low male fertility

Yonghua Han, Junsong Pan, Paradee Thammapichai, Zongyun Li, Yiqun Weng
crop journal 2016 v.4 no.4 pp. 275-279
Cucumis hystrix, Cucumis sativus, allopolyploidy, chromosome pairing, chromosomes, crops, cucumbers, fluorescence in situ hybridization, genome, interspecific hybridization, male fertility, meiosis, pollen, seed set, self-pollination, tetraploidy
Interspecific hybridization and allopolyploidization contribute to the improvement of many important crops. Recently, we successfully developed an amphidiploid from an interspecific cross between cucumber (Cucumis sativus, 2n=2x=14) and its relative C. hystrix (2n=2x=24) followed by chemical induction of chromosome doubling. The resulting allotetraploid plant was self-pollinated for three generations. The fertility and seed set of the amphidiploid plants were very low. In this study, we investigated the meiotic chromosome behavior in pollen mother cells with the aid of fluorescence in situ hybridization, aiming to identify the reasons for the low fertility and seed set in the amphidiploid plants. Homologous chromosome pairing appeared normal, but chromosome laggards were common, owing primarily to asynchronous meiosis of chromosomes from the two donor genomes. We suggest that asynchronous meiotic rhythm between the two parental genomes is the main reason for the low fertility and low seed set of the C. hystrix–cucumber amphidiploid plants.