Genetic Variation Within Chinese and Western Cultivated Oat Accessions

Abstract

Oat (Avena sativa L.) have been cultivated in China for approximately 2000 years. Little is known about the origin of Chinese oat, and Western access to this germplasm pool has been limited. The objective of this research was to compare the relative levels of genetic diversity in a sample of 119 Chinese hulled and hull-less accessions with a sample of 33 hulled Western A. sativa and A. byzantina C. Koch accessions using RAPD analysis. Seventy-two polymorphic fragments were amplified by 18 primers in the Chinese and Western accessions. The Chinese germplasm pool exhibited a lower level of diversity than the Western germplasm pool. Sixty-seven polymophic fragments were detected in Western germplasm versus 49 in Chinese germplasm. The polymorphic index for Chinese germplasm was one-half that observed for Western germplasm, and the probability of observing a phenotype in Chinese germplasm that was not present in Western germplasm was one- tenth the reciprocal probability. A 152 × 152 relationship matrix of all pairwise combinations of the Chinese and Western accessions was constructed based on Jaccard’s distance estimates. The results suggested that the Chinese accessions, especially the hulled types, had a greater affinity with the nineteenth century A. sativa germplasm pool of northern and central Europe than with recent North American spring- and fall- sown cultivars, or the A. byzantina cultivars of Mediterranean origin.