Relationships between Population Size, Genetic Diversity and Fitness Components in the Rare Plant Dictamnus albus in Central Germany

Abstract

An increasing number of studies support the hypothesis that smaller populations face a higher risk of extinction, and declining population sizes are therefore one of the focal points in plant conservation. In small populations, loss of genetic diversity is often related to reduced reproductive fitness. For the rare Dictamnus albus in Central Germany, an earlier study had already confirmed a significant correlation between population size and genetic diversity. In order to assess whether these variables correlate with fitness components, plant height; flower, fruit and seed production; and germination were studied in a total of 11 populations of different size. In the seven populations that were sampled over two consecutive years, differences among populations and among years were tested using a Two-Way ANOVA. Co-linearity among variables was assessed using principal component analysis (PCA), followed by calculating correlations between ordination axes and both population size and genetic diversity. Plant height and flower number were uncorrelated to the other variables and, together with germination, did not show any correlation to either population size or genetic diversity. However, both size and genetic diversity of populations correlated significantly with other PCA axes that reflected reproductive components such as fruit number, seed number, seed fruit ratio, and seed mass. Our results support the idea that reproduction is hampered in small populations and raise concerns over the loss of genetic diversity in D. albus.

Genetic diversity of six arable plants in relation to their Red List status

“…In order to ensure reproducibility, 10 samples of each species were run in at least two independent RAPD PCRs. Although RAPDs have received severe criticism in recent years, some Significance level * P \ 0.05 reviews (e.g., Nybom and Bartish 2000;Nybom 2004) and a great number of successful applications (e.g., Hensen and Wesche 2006;Esfeld et al 2008;Schiebold et al 2009) support the RAPD-based approach employed in our study. In addition, we also performed an AFLP analysis for B. rotundifolium, which included the same populations and the same plants (Kühne unpubl.)…”

DArTseq Genotyping Reveals High Genetic Diversity of Polish Rye Inbred Lines

“…The previous phylogenetic study on rye inbred lines comprised much fewer forms: 30 and 48 in the works published by Bolibok et al (2005) and Myśków et al (2010), respectively. The size of the population analyzed with respect to genetic diversity has been shown to be an important factor affecting relationships between individuals (Hensen and Wesche, 2006). The size of the population analyzed with respect to genetic diversity has been shown to be an important factor affecting relationships between individuals (Hensen and Wesche, 2006).…”

The Ecological Characteristics of Seed Germination and Seedling Establishment of <i>Manglietia patungensis</i>: Implication for Species Conservation

“…Small-sized populations are particularly susceptible to extinction because of reduced fitness resulting from inbreeding depression and to random demographic and environmental effects [8,19]. Currently, for many threat-ened plant taxa, the relative importance of the contemporary ecological factors which constrain population growth are poorly understood and little is known about the management actions required to maintain stable populations of plants.…”