Diabrotica barberi Smith & Lawrence, the northern corn rootworm, and Diabrotica longicornis (Say) (Coleoptera: Chrysomelidae), are currently recognized as closely related chrysomelid species. Hybridization has been proposed to occur between them, although the viability of hybrids has never been tested. The objective of this study was to assess life-history parameters of D. barberi,D. longicorni...

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Crosses between divergent populations of the copepod Tigriopus californicus typically result in fitness reductions for both F2 and backcross hybrids. Because females in this species lack chiasmatic meiosis, both recombinant and nonrecombinant backcross hybrids can be created. Recombinant hybrids were found to have significantly faster development time for both males and females in 2 pairs of cr...

Gene flow from genetically modified (GM) crops to wild relatives might affect the evolutionary dynamics of weedy populations and result in the persistence of escaped genes. To examine the effects of this gene flow, the growth of F1 hybrids that were formed by pollinating wild soybean (Glycine soja) with glyphosate-tolerant GM soybean (G. max) or its non-GM counterpart was examined in a greenhou...

Various models purporting to explain natural hybrid zones make different assumptions about the fitness of hybrids. One class of models assumes that hybrids have intrinsically low fitness due to genetic incompatibilities, whereas other models allow hybrid fitness to vary across natural environments. We used the intrinsic rate of increase to assess lifetime fitness of hybrids between two species ...

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 genet...

To create novel tomato (Solanum lycopersicum) germplasm, a wild relative, S. pimpinellifolium (a red-fruited LA1585 accession), was used as the male parent to cross with yellow-fruited mutant, e9292 (S. lycopersicum). Forty-four morphological characteristics were examined in present study; 22 (LA1585) traits and six lycopersicum (e9292) dominant hybrids (first generation, F1); 10 intermediate t...

We crossed the C3 species Atriplex prostrata with the C4 species Atriplex rosea to produce F1 and F2 hybrids. All hybrids exhibited C3-like δ(13)C values, and had reduced rates of net CO2 assimilation compared with A. prostrata. The activities of the major C4 cycle enzymes PEP carboxylase, NAD-malic enzyme, and pyruvate-Pi dikinase in the hybrids were at most 36% of the C4 values. These results...