Horizontal Gene Transfer (HGT) in the Course of Plant Evolution

Abstract

Horizontal gene transfer (HGT) of genetic material across different species is now a familiar event even in the case of eukaryotes. Growing evidence highlights the significant role of HGT in shaping modern plant genomes. HGT has also been attributed to the development of various stress-response genes of land plants and their adaptive evolution over millions of years. Multiple cases have been observed on incidents of transfer of genes between plants and other organisms such as bacteria, fungi, viruses and even animals. Recent genomic mining efforts in plants have revealed several incidents of HGTs that have crucial implications in the field of crop improvement as well. Knowledge of horizontally transferred genes associated with plants and their dependent biota combined with modern molecular biological tools will prove to be useful in opening up a new dimension in the plant breeding world, as supported by various recent reports. This could aid in developing novel stress-resilient varieties in the future by exploiting or manipulating HGTs which might have occurred in crops, related species or associated organisms. This review synthesizes current knowledge on the occurrences of HGTs, their detection methods, importance of HGTs in plant evolution and the impacts they had and might have on advanced plant breeding. HGT explorations represent an emerging field for molecular biologists and plant breeders, offering them valuable insights into the hidden layers of genetic exchange that continues to shape plant genomes and their diversity even today.