Hybridization is an important process which led to many lineages evolution. Increasing genomic tool and methods in genomic analyses, make gene flow between different taxa which generate new phenotypic diversity, permit for variation of new species, and donate to speciation. Hybridization lead to phenotypic changes through the expression of hybrid vigor. On longer evolution time scales, hybridization cause limited alteration through the introgression of new alleles and transgressive segregation and, in some cases caused the formation of new isolates. The abundance and evolution studies of hybridization have interesting role in biology science. A lot of evidences concerning how and why hybridization contributes to biological diversity currently being investigated were first proposed tens and even hundreds of years ago. In this Update, we discuss how new advancements in genomic and genetic tools are revolutionizing our ability to document the occurrence of and investigate the outcomes of hybridization in plants. Moreover, the impacts of hybrids can either be positive or negative. Among the positive attributes of hybrids that have been exploited is heterosis, which results either from dominance, over-dominance or epistasis. Negative ones include sterility, arrested growth of the pollen tube, failure to nuclear reprogramming, proper placenta formation and maternal immune response and embryo abortion.
Hybridization; Individuals; Species; Sterility
From unlike populations that are genetically different or through crossing two individuals, the natural or artificial process called hybridization lead to production of hybrids . The previous action causes no genetic material changes in the quantity or quality and the contents of the DNA remained constant but the genes forms novel groups leading to positive attractive characters or new phenotypic individuals. Many problems including sexual incompatibility, polyembryony, and male or female sterility may appeared due to hybridization process . For plant growth enhancement and plant developments, the hybridization process is used to: 1- produce a new plant species or hybrids with some wanted characters, 2- mix some important characters in definite plants and produce one plant with certain characters and finally to use the new hybrid in crop production and biological applications. Generally, hybridization mainly aimed to produce a hybrid with a new genetic material that differed from the original parents.
In normal habitats, hybridization causes certain population differences which may lead to strong reproductive barrier evolutions to create novel isolates or verities. It is also used to produce novel crops with special characters and cause popular differences between lineages in addition to it produce new verities. DNA analysis and sequencing of the produced crops confirm the importance of genetic introgression and hybridization. This cause a progress in detection techniques used for studying gene flow in natural hybridization and phylogenomic analysis due to genomic information’s which cause or inform about gene flow [3,4]. There is increasing respect about the widespread of hybridization which lead to a significant evolution, leading to believing that plants may affect extending to animals [5,6]. Concerning animal flora and fauna reproduction protocols, normal hybridizations process a vital role in genetic material morphology and evolution of insects and birds taxa. Mainly, hybridization appeared among two differ animal races which may change to wild types [7-11]. Concerning bird’s hybridization, the analysis of genomic information gives ornithologists to discover the ecological and evolution processes of multispecies hybridization .