Genetic relationship estimation in guineagrass (Panicum maximum Jacq.) assessed on the basis of simple sequence repeat markers

• Published in: Grassland science 2007-09, Vol.53 (3), p.155-164
• Main Authors: Ebina, Masumi, Kouki, Kaori, Tsuruta, Shin-ichi, Akashi, Ryo, Yamamoto, Toshiya, Takahara, Manabu, Inafuku, Masahito, Okumura, Kenji, Nakagawa, Hitoshi, Nakajima, Kousuke
• Format: Article
• Language: English
• Subjects: Genetic relationship; guineagrass; Panicum maximum; Panicum maximum Jacq; SSR marker
• ISSN: 1744-6961; 1744-697X
• DOI: 10.1111/j.1744-697X.2007.00086.x

Estimation of genetic relationship for the efficient genetic resources utilization in the breeding programs of guineagrass (Panicum maximum Jacq.) is of utmost importance. Thirteen simple sequence repeat (SSR) markers, developed from genomic and cDNA clones, were successfully employed for estimating genetic relationship in guineagrass based on the analysis of 77 accessions. A genomic library enriched for (AG)/(TC) and expressed sequence tag (EST) sequences were screened for repeat motifs in guineagrass. A total of 13 SSR markers including eight from genomic clones and five from EST, were developed. Of these, eight, four and one SSR markers have perfect, interrupted and compound repeat motifs, respectively. One SSR has trinucleotide repeat motif of AGT, whereas the other 12 markers have dinucleotide motif of AG. The 13 SSR primer sets produced 1-4 amplified fragments within accessions, putatively corresponding to alleles derived from autotetraploidy of guineagrass. One hundred and ninety putative alleles were generated by 13 SSR in the 77 guineagrass accessions assayed. The values of power of discrimination (PD) ranged 0.449-0.968 with an average value of 0.859. Polymorphic information content (PIC) ranged 0.399-0.951. A phenogram of 77 guineagrass accessions obtained based on the genetic similarity with 13 SSR, revealed six major groups. The results suggested that the center of original region of guineagrass is Kenya, which agrees with an earlier study based on morphological analysis. The wide distribution of the guineagrass accessions strongly supports the assumption of intercrossing with the diploid sexual materials in natural habitat.