Molecular evidence of allodiploidy in F₁ gametophytic blades from a cross between Neopyropia yezoensis and a cryptic species of the Neopyropia yezoensis complex (Bangiales, Rhodophyta) by the use of microsatellite markers

Highlights

• Three MS markers developed for N. yezoensis could be used to genotype Neopyropia sp. 2.

• The MS analysis indicated that the hybrid blades in this study were allodiploid.

• The results support the possibility of polyploidy breeding of marine crop species.

• The MS markers could serve as useful tools for studies on sympatric speciation.

Abstract

We investigated whether six microsatellite (MS) markers previously developed for two marine crop species, Neopyropia yezoensis and Neopyropia tenera (formerly Pyropia yezoensis and Pyropia tenera, respectively), are useful for molecular analysis of gametophytic blades resulting from a cross between Neopyropia yezoensis and Neopyropia sp. 2, a cryptic species of the N. yezoensis complex. Three (Pye1, Pye13, and Pye38) of the six MS markers could be used to genotype the cryptic species Neopyropia sp. 2. Using these three MS markers, we evaluated whether the F₁ gametophytic blades resulting from the cross between N. yezoensis and the cryptic species Neopyropia sp. 2 are allodiploid in the haploid gametophytic phase. The F₁ blades that developed from both conchospore and archeospore exhibited heterozygous genotypes at two MS loci (Pye13 and Pye38). The MS marker analyses clearly showed that the F₁ blades were allodiploid, strongly supporting the findings of a previous study that was based on a single CAPS marker. In addition, the MS markers employed in this study could serve as useful tools for studies on allopolyploidy in and sympatric speciation of the marine alga Neopyropia.