Genetic variation and interspecific hybridization among natural populations of zoysiagrasses detected by RFLP analyses of chloroplast and nuclear DNA.

Abstract

Genetic variations among 17 accessions of zoysiagrasses collected from natural populations in Japan were investigated by RFLP analyses of chloroplast DNA (cpDNA) and nuclear DNA. These accessions were classified into five species based on morphological characteristics: Zoysia japonica, Z. matrella, Z. tenuifolia, Z. sinica, and Z. macrostachya. On the basis of eight kinds of RFLPs in cpDNAs detected across accessions, six chloroplast genome types (types A-F) were identified. Although type-A cpDNA was shared by five accessions of japonica and four accessions of matrella, derivative cpDNAs of type A, which each arose by a mutation, were identified in one accession of japonica (type B) and in two accessions of matrella (type C). One accession of japonica which showed spikelets similar to those of shapes macrostachya, contained type-F cpDNA as did sinica and macrostachya. The two accessions of tenuifolia each showed a specific cpDNA type, i.e. types D and E.Genetic relationships among the 17 accessions were investigated by the RFLP analyses of nuclear DNA with 20 genomic and gene probes. A dendrogram constructed with genetic distances calculated from the RFLP patterns indicated four major groups among them. Six accessions of japonica comprised one group, whereas the one accession of japonica possessing the type-F cpDNA was clustered with macrostachya and sinica. Four accessions of matrella with type A cpDNA constituted another group in the dendrogram, showing a closer relationship to the japonica accessions than to the other two accessions of matrella. The remaining two accessions of matrella and tenuifolia accessions were grouped together. These data indicate that zoysiagrasses distributed in Japan harbor highly genetic variations, and that interspecific hybridization has occurred in natural populations.

Development and characterization of simple sequence repeat markers in Zoysia japonica Steud.

“…Three species of zoysiagrass, Z. japonica , Z. matrella and Z. tenuifolia , can be used to generate interspecific hybrids in all combinations (Forbs, 1952), and it appears that based on morphological observation, many naturally occurring interspecific hybrids can be found in several ecotypes (Fukuoka, 2000). This assumption is also likely to apply to zoysiagrass following both genetic and phylogenetic analysis of zoysiagrass collections in Japan (Yaneshita et al ., 1997). In our study, two accessions, ‘Taketomikaiji 2’ and ‘Katsuren 1–1’, indicated a close relationship to Z. tenuifolia accessions, although their morphological characters differed considerably from Z. matrella and Z. sinica var.…”

“…Traditional varietal identification of zoysiagrass has been performed primarily by examining morphological characteristics; however, this is often difficult with closely related cultivars (Yaneshita et al ., 1997). In addition, the ease with which it propagates vegetatively adds an additional burden with regard to variety protection.…”

Genetic diversity of chloroplast DNA in Zoysia and other warm‐season turfgrasses

“…2006). Yaneshita et al . (1997) showed that five species of Zoysia could be classified into six haplotypes based on eight RFLP in cpDNA.…”

Isozyme and RAPD studies in Prosopis glandulosa and P. Velutina (Leguminosae, Mimosoideae)

“…Biochemical and molecular markers have been used to enhance understanding of plant population genetic structure (Soltis et al, 1992). Among several efficient methods for revealing genetic variability within and among plant populations, some of the most widely applied are isozyme electrophoresis (Hamrick and Allard, 1972;Hamrick and Godt, 1990), random amplified DNA polymorphism -RAPDs - (Wolff and Peters-van Rijn, 1993;Wachira et al, 1995;Brummer et al, 1995;Swoboda and Bhalla, 1997;Palacios and Gonzalez-Candelas, 1997), and restriction fragment length polymorphisms -RFLPs - (Keim et al, 1989;Hong et al, 1993;Yanesita et al, 1997). In the genus Prosopis, previous isoenzymatic studies in some Algarobia Section species have shown low differentiation among species and populations coupled with high variability within populations (Saidman, 1985(Saidman, , 1986(Saidman, , 1990(Saidman, , 1993Saidman and Vilardi, 1987;Verga, 1995).…”