Reproductive biology and population genetic structure ofKandelia candel(Rhizophoraceae), a viviparous mangrove species

Abstract

The pollination biology, mating system, and population genetic structure of Kandelia candel were investigated. Field observations on its pollination and reproductive biology suggested that this species is pollinator dependent for fruit set, and bee activities can lead to substantial geitonogamous selfing. Quantitative analysis of the mating system parameters was performed using progeny arrays assayed for allozyme markers. Multilocus outcrossing rates (t(m)) were estimated to be 0.697 ± 0.091 and 0.797 ± 0.062 in two populations. In comparison to other plant species with mixed-mating system, the level of allozyme variation was very low in the 13 populations sampled along the coastlines of Hong Kong. At the species level, the proportion of polymorphic loci was 20%, number of alleles per locus was 1.2, and heterozygosity was 0.0362. The total gene diversity was primarily distributed within populations (H(S )= 0.0339), and the coefficient of genetic differentiation among populations was low (G(ST )= 0.064). This pattern of population genetic structure suggests that gene flow, primarily in the form of water-dispersed seedlings in viviparous mangrove species, is not as limited as previously thought. However, microgeographic pattern in allele frequency at the marker loci could still be detected between the western and eastern coastal populations.

Reproductive Strategy of Aegiceras corniculatum L. (Blanco.) - A Mangrove Species, in MNP&S, Gujarat, India

“…Ge and Sun (1999) and Aluri (1990) found that A. corniculatum is predominantly pollinator-dependent for fruit setting. Similar observations were made for Kandelia caldel, another mangrove species (Sun et al, 1998). Nevertheless, the foraging pattern and asynchrony in the flowering processes within an inflorescence tend to geitonogamy in many mangrove species (Sun et al, 1998;Ge & Sun, 1999) which is in conformity with the findings of present study.…”

A Study of Conservation Genetics in Cupressus chengiana, an Endangered Endemic of China, Using ISSR Markers

“…Amplified bands were scored as present (1) or absent (0). Popgene version 1.31 (Yeh et al, 1997), AMOVA (Excoffier et al, 1992), and NTSYSpc version 2.02c (Rohlf, 1998) were used to calculate parameters in genetic diversity as follows: (1) N p (number of polymorphic loci); (2) PPB; (3) A o (observed number of alleles per locus) and A e (effective number of alleles per locus); (4) H e (Nei's gene diversity) and I (Shannon's information index); (5) Nei's genetic distances (D) and genetic identity (IN); (6) cluster analysis with unweighted pair group with arithmetic average (UPGMA; Sun et al, 1998); (7) coefficient of gene differentiation among populations within species (G st ; Nei, 1972); (8) …”

Global distribution and genetic discontinuities of mangroves – emerging patterns in the evolution of Rhizophora

“…Based on prior notions of dispersal ability and incomplete taxonomy, some discontinuities in mangrove plants were unexpected occurrences of restricted dispersal and gene flow, especially within the global regions. By contrast, areas away from discontinuities have unexpectedly low diversity both within and among populations (e.g., see Huang and Chen 1997;Sun et al 1998;Parani et al 1998).…”