Non-random mating in a Secale cereale L. (rye) population

Abstract

The mating system in an experimental population of rye (Secale cereale L.) cv. Merced was studied using eight polymorphic isozyme loci as genetic markers and two progeny samples from a large population: 20 emasculated mother plants (obligately cross-pollinating) and 100 non-emasculated mother plants. Merced rye showed a significant frequency of self-fertilization (s 1 -t) in a previous generation, but in the generation under study the outcrossing frequency was not significantly different from t 1. This fact suggests that environmental factors can affect the rate of outcrossing vs. selfing (self-fertilization). In spite of the outcrossing rate of t = 1, the large progenies from emasculated plants (100 seeds per plant) demonstrated that pollination was not completely at random. This represents a violation of the generally accepted mixed-mating model on which most methods used to estimate mating parameters are based. Temporal heterogeneity and the differential ability of gametophytes to fertilize are possible causes of the non-randomness of mating. It is concluded that, although violations of the assumption of the mixed-mating model can bias the estimates, most of the estimated outcrossing values clearly differ from complete outcrossing.

Genetic diversity of Secale cereale L. in Iran as measured using microsatellites

“…These were likely correlated with the relatively uniform ecological conditions of the North of Iran, along the Caspian Sea shore and highly variable conditions along Zagros Mountains (West and Northwest of Iran). This is in accordance with Polanco et al (1994) which provided evidences for the influence of environmental conditions on the rate of outcrossing versus selfing in rye, which finally affects the inter-and intra-population diversity.…”

An Integrative Test of the Dead-End Hypothesis of Selfing Evolution in Triticeae (Poaceae)

“…Species with known mating systems were used to guide our classification. These include one perennial outcrosser ( Psathyrostachys juncea , selfing rate ( S ) = 0; Yang et al 2008), three annual outcrossers ( Dasypyrum villosum , S = 0.25, Depace and Qualset 1995; S. cereale , S = 0; Polanco et al 1994; and Aegilops speltoides , unknown selfing rate but reported as allogamous; Zohary and Imber 1963; Dvorak et al 1998; Zaharieva and Monneveux 2006), and four annual selfers ( Ae. tauschii , S = 0.98; Dvorak et al 1998; T. monococcum , S = 0.95; Hegde et al 2000; H. vulgare , S = 0.98; Kahler et al 1975; von Bothmer et al 1995; Parzies et al 2000; Abdel‐Ghani et al 2004; Morrell et al 2005; and H. marinum , unknown selfing rate but reported as inbred; von Bothmer et al 1995).…”

“…These include one perennial outcrosser (Psathyrostachys juncea, selfing rate (S) = 0; Yang et al 2008), three annual outcrossers (Dasypyrum villosum, S = 0.25, Depace and Qualset 1995;S. cereale, S = 0;Polanco et al 1994;and Aegilops speltoides, unknown selfing rate but reported as allogamous; Zohary and Imber 1963;Dvorak et al 1998;Zaharieva and Monneveux 2006), and four annual selfers (Ae. tauschii, S = 0.98; Dvorak et al 1998;T.…”

Biodiversity of Secale strictum in Iran measured using microsatellites

“…These were likely correlated with the relatively low ecological variability in the North of Iran, along the Caspian Sea shore and highly variable conditions along Zagros Mountains (West and Northwest of Iran). As Polanco et al (1994) have noted, the environmental conditions affect the rate of outcrossing vs. selfing in rye, which finally affects the inter-and intera-population diversity. The higher genetic diversity of S. strictum in the Northwest and the West of Iran can be correlated with the high ecological variation in these regions.…”