Factors Influencing Male Reproductive Success in a Cryptomeria japonica Seed Orchard Revealed by Microsatellite Marker Analysis

Abstract

We investigated the influence of male flower production, floral synchrony and inter-tree distances on male reproductive success in a miniature seed orchard of Cryptomeria japonica. We used six microsatellite markers to determine the paternity of each seed. In the seed orchard, the average pollen contamination and clonal self-fertilization rates were 38.7 % and 1.7 %, respectively. The level of male reproductive success of constituent clones varied from 0.0 to 15.7 %. Five clones showing the highest male reproductive success contributed ca. 30 % of all analyzed seeds as a pollen donor after excluding contamination by external sources of pollen. The statistical analyses showed that male reproductive success was strongly influenced by male flower production of each clone and, possibly, by their distance to the mother trees. The linear regression which included male flower production and floral synchrony as independent variables, however, accounted for only 14.7 % of variation of male reproductive success, suggesting that other factors such as pollen competition might also influence male reproductive success. Since we found no significant correlation between male reproductive and female reproductive successes, it may be better to equalize male and female reproductive successes independently.

Use of molecular markers for estimating breeding parameters: a case study in a Pinus pinaster Ait. progeny trial

“…In addition, Fernandes et al (2008), in a study performed in a P. pinaster CSO, concluded that the probability that a seed embryo sampled from a mother tree was derived from an outcrossing event was 90.1±2.3%. The absence of selfing found in our study was not surprising in spite of the selffertilization rates of around 5% found in most seed orchards examined to date (Moriguchi et al 2007). In fact, many of the seeds and seedlings produced by inbreeding have a lower viability than outcrossed individuals, so that the inbreds often remain undetected because of large-scale early mortality (Linhart 2000).…”

Mating patterns and pollen dispersal in four contrasting wild cherry populations (Prunus avium L.)

“…Bigger trees may indeed exhibit higher flowering intensity resulting in higher attractiveness to the pollinator or higher fertilisation probability for wind-pollinated species. A few studies support this hypothesis: male flower production had a strong effect on male reproductive success (Cryptomeria japonica, Moriguchi et al 2007;Sorbus torminalis, Oddou-Muratorio et al 2005) or on flower visitation (in the herbaceous plant Silene latifolia, Shykoff and Bucheli 1995). However, we do not know whether d.b.h and flowering intensity are strongly correlated in P. avium.…”

Microsatellites used to establish full pedigree in a half-sib trial and correlation between number of male strobili and paternal success

“…Moriguchi et al (2007) investigated the influence of floral synchrony on paternity contribution in Cryptomeria japonica, but did not find any significant effect in a pollen shedding period of 1.5 months (Moriguchi et al, 2005), and thereby considerably longer than in A. nordmanniana. Like us, Moriguchi et al (2007) found a significant relationship between male strobili production and male reproductive success, but their linear regression model only explained around 15% of the variation in siring success. In Pinus thunbergii, Goto et al (2005) also found a significant association between male fecundity and male reproductive success -their regression model explained around 43% of the variance -again with a non-significant effect of floral synchrony.…”