| genetic diversity in diploid vs. tetraploid rorippa amphibia (brassicaceae). | the frequency of polyploidy increases with latitude in the northern hemisphere, especially in deglaciated, recently colonized areas. the cause or causes of this pattern are largely unknown, but a greater genetic diversity of individual polyploid plants due to a doubled genome and/or a hybrid origin is seen as a likely factor underlying selective advantages related to life in extreme climates and/or colonization ability. a history of colonization in itself, as well as a recent origin, and possibl ... | 2007 | 17845429 |
| different flooding responses in rorippa amphibia and rorippa sylvestris, and their modes of expression in f1 hybrids. | the river floodplain species rorippa amphibia, rorippa sylvestris, and their hybrid rorippa x anceps were studied here, with the aim of identifying potential species differences with respect to flooding tolerance, and of assessing their expression in f1 hybrids. parents and their f1 hybrids were subjected to three flooding treatments mimicking natural conditions, and growth-related and leaf morphological traits were compared. in contrast to r. sylvestris, r. amphibia responded to waterlogging by ... | 2008 | 18631292 |
| segregation models for disomic, tetrasomic and intermediate inheritance in tetraploids: a general procedure applied to rorippa (yellow cress) microsatellite data. | tetraploid inheritance has two extremes: disomic in allotetraploids and tetrasomic in autotetraploids. the possibility of mixed, or intermediate, inheritance models has generally been neglected. these could well apply to newly formed hybrids or to diploidizing (auto)tetraploids. we present a simple likelihood-based approach that is able to incorporate disomic, tetrasomic, and intermediate inheritance models and estimates the double-reduction rate. our model shows that inheritance of microsatelli ... | 2008 | 18689891 |
| other tetraploid species and conspecific diploids as sources of genetic variation for an autotetraploid. | • premise of the study: most plants are polyploid and have more than two copies of the genome. the evolutionary success of polyploids is often attributed to their potential to harbor increased genetic variation, but it is poorly understood how polyploids can attain such variation. because of their formation bottleneck, newly formed tetraploids start out with little variation. tetraploids may attain genetic variation through a combination of new mutations, recurrent formation, and gene exchange w ... | 2010 | 21616824 |