during their evolution (Soltis et al. 2004). Hybrid speciation is another important pheno-
menon. Interspecific hybridization and subsequent introgression of the portion of the
genome of one species into that of another (Fig. 2.14) have often been recognized as a
source of genetic variation and genetic novelties, and in some cases successful hybridi-
zation events have promoted rapid speciation radiation. The complexities of plant genetics
can be traced to reproductive biology and mating systems in plants, which is an area of
research that is very active and dynamic.
2.5 Conclusion
After biotechnologists introduce or manipulate genes in plants, if all goes as expected, the
new genes should be part of the genomic fabric and behave like normal plant genes.
Therefore, they should follow the laws of Mendelian genetics and be passed on to future
generations like other genes of the particular species. Therefore, it is important for the
plant biotechnologist to know botany and basic genetics. Transgenes also become part of
breeding programs, which is why understanding the fate of transgenes in new plant cultivars
is important—the subject of the next chapter.
Figure 2.14.Hybridization and genetic integration between closely related species allows for the
incorporation of genetic material from one species to another.
2.5. CONCLUSION 41