Characterization and identification of ISSR markers associated with oil content in sea buckthorn berries

Bioactive oils extracted from sea buckthorn (Hippophae rhamnoides) berries contain highly nutritional and medicinal compounds; however, the oil contents of sea buckthorn berries are very low. Thirteen inter-simple sequence repeat (ISSR) primers were used to identify markers associated with oil content of dry pulp in 51 cultivars and lines, which clustered into three major groups based on 137 polymorphic markers. Dry pulp oil contents in 45 cultivars and lines in Group I ranged from 6.6 to 33.1%; these accessions belonged to H. rhamnoides ssp mongolica and its hybrids with H. rhamnoides ssp sinensis. Three lines (H. rhamnoides ssp mongolica) in Group II had high dry pulp oil contents (33.7 to 37.5%), whereas three lines of hybrids in Group III had low dry pulp oil contents (10.9 to 17.5%). The dry pulp oil content of H. rhamnoides ssp mongolica (27.2 ± 0.9%) was higher than that of hybrids (12.0 ± 1.2%) (P < 0.01). Four ISSR markers (881₃₄₀, 825₁₀₀₀, 817₃₈₀, and 807₁₁₀₀) had positive association with high dry pulp oil content (P < 0.01) using stepwise multiple regression analysis. The use of these ISSR markers is a potential strategy to select genotypes with high dry pulp oil content and suitable parental combinations for improvement of sea buckthorn berries.