Reproductive fitness of hybrids between Senecio jacobaea and Senecio aquaticus (Asteraceae)
نویسندگان
چکیده
Natural hybridization is increasingly recognized as an important process for the ecology and evolution of natural plant populations and species. There is a great need to initiate more studies based on natural populations in order to elucidate the possible role of hybrids in nature. The reproductive success of early generation hybrids can make or break hybrid lineages and may determine the genetic structure of hybrid swarms or the potential for gene flow through future generations, but studies of hybrid reproductive success are lacking. Here we measured components of male and female reproductive success in Senecio jacobaea and S. aquaticus (Asteraceae) species and F1 hybrids between these species under laboratory conditions, and we measured reproductive output from crosses producin F1, F2, and backcross (BC) generation hybrids. F1 hybrids were readily produced, and on average, the success of crosses producing subsequent generations (F2, BC) decreased (though remained substantial), but the success of crosses was highly dependent on the genotypes involved. Also, F1 hybrids were bigger, produced more flowers, and therefore produced more pollen than parental plants. Finally, crosses between parents were asymmetrical, such that S. aquaticus produced more and larger F1 seeds than did S. jacobaea.
منابع مشابه
Natural hybridization between Senecio jacobaea and Senecio aquaticus: molecular and chemical evidence.
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