Muhammad Mubashar Zafar 1,2, Aqsa Ijaz 3, Zunaira Anwar 3, Amir Shakeel2, Fariha Qadir4, Hira Kamal 5*, Abdul Razzaq 4,1* and Xuefei Jiang 1*
1Sanya Institute of Breeding and Multiplication/School of Tropical Agriculture and Forestry, Hainan University, Sanya, China 2Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad, Pakistan 3Nuclear Institute for Agriculture and Biology College (NIAB-C), Pakistan Institute of Engineering and Applied Sciences (PIEAS), Nilore, Islamabad, 45650 Pakistan 4Institute of Molecular Biology and Biotechnology, the University of Lahore, Lahore, Pakistan 5Department of Plant Pathology, Washington State University, Pullman, WA, USA
*Corresponding author: hira.kamal111@gmail.com (AK); biolformanite@gmail.com (AR); xuefei.jiang@hai
Approximately 10-15 million years ago, this genus experienced rapid global radiation, leading to the emergence of eight major genome groups (A through G and K) consisting of 13 chromosomes in each group. Moreover, over the past 1-2 million years, the transoceanic dispersal of an A-genome taxon to the New World and subsequent hybridization with a native D-genome diploid resulted in the rise of allopolyploid cotton. This evolutionary process led to the diversification of three modern lineages encompassing seven described species, including the economically significant G. hirsutum L. and G. barbadense L. A parallel evolution, driven by human intervention, unfolded as these two allopolyploids were domesticated. Simultaneously, the independent domestication of two A-genome diploids, G. arboreum L. and G. herbaceum L., originally from Africa-Asia occurred. Recent genomic investigations have unlocked its paleopolyploid history of diploid species and shed light on the surprisingly high frequency of natural interspecific hybridization within and between genome groups. Furthermore, these studies have elucidated the diverse molecular mechanisms underlying allopolyploid genome evolution and provided a more refined understanding of the evolutionary association among the gene pools of each of the four cultivated species. Gossypium is an exceptionally diverse group, encompassing variations in fiber morphology, stress tolerance, and other agronomic characteristics, and represents a vast resource for breeders striving to develop improved cotton varieties. This comprehensive understanding of Gossypium genome evolution and its implications for targeted breeding paves the way for advancements in sustainable cotton agriculture.