Genomic constitution, allopolyploidy, and evolutionary proposal for Cynodon Rich. based on GISH

• Published in: Protoplasma Vol. 259; no. 4; pp. 999 - 1011
• Main Authors: Chaves, Ana Luisa Arantes, Carvalho, Pedro Henrique Mendes, Ferreira, Marco Tulio Mendes, Benites, Flávio Rodrigo Gandolfi, Techio, Vânia Helena
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.07.2022; Springer Nature B.V
• Subjects: Allopolyploidy; Biomedical and Life Sciences; Cell Biology; Chromosome number; Chromosomes; Cynodon; Diploids; Gametes; Genome, Plant - genetics; Genomic in situ hybridization; Genomics; Hybridization; In Situ Hybridization; Life Sciences; Nomenclature; Original Article; Phylogeny; Plant Sciences; Pollen; Polyploidy; Species; Taxonomy; Zoology; Hybrid; Unreduced gametes; Polyploidy; Genomic analysis; Cytotype; Evolutionary history
• ISSN: 0033-183X; 1615-6102
• DOI: 10.1007/s00709-021-01716-z

Polyploidy is the main mechanism for chromosome number variation in Cynodon . Taxonomic boundaries are difficult to define and, although phylogenetic studies indicate that some species are closely related, the degree of genomic similarity remains unknown. Furthermore, the Cynodon species classification as auto or allopolyploids is still controversial. Thus, this study aimed to investigate the genomic constitution in diploid and polyploid species using different approaches of genomic in situ hybridization (GISH). To better understand the hybridization events, we also investigated the occurrence of unreduced gametes in C. dactylon diploid pollen grains. We suggest a genomic nomenclature of diploid species as DD, D 1 D 1 , and D 2 D 2 for C. dactylon , C. incompletus , and C. nlemfuensis , and DDD 2 D 2 and DD 2 D 1 D 1 for the segmental allotetraploids of Cynodon dactylon and C. transvaalensis , respectively. Furthermore, an evolutionary proposal was built based on our results and previous data from other studies, showing possible crosses that may have occurred between Cynodon species.