Genetic Variation in Three Endangered Species of Encholirium (Bromeliaceae) from Cadeia do Espinhaço, Brazil, Setected using RAPD Markers

Abstract

Encholirium is a Brazilian genus of Bromeliaceae that occurs exclusively in rocky landscapes. This work aimed to generate basic information for the conservation of three Encholirium species that are endemic to the rocky mountains of Cadeia do Espinhac¸o, employing population genetic analyses. E. pedicellatum and E. biflorum have only one very small population each, both occurring in unprotected, private land sites, being critically endangered. E. subsecundum is more widespread, and some of its populations dwell in protected areas. Five Random Amplified Polymorphic DNA (RAPD) primers generated approximately 60 polymorphic bands for each species. This technique demonstrated the presence of a single RAPD profile for every individual sampled (except for one clone found in E. biflorum). High levels of genetic variability were not expected, due to the clonal habit of the plants and small size of the populations. Populations of E. biflorum and E. pedicellatum presented, respectively, 16.06% (U st = 0.16, p < 0.001) and 8.44% (U st = 0.08, p < 0.001) of the total genetic diversity attributable to genetic differences among groups within the populations. In E. subsecundum, 14.52% (U st = 0.15, p < 0.001) of the total genetic diversity was found among populations. Estimates of the Shannon's Diversity Index provided similar results. These results are valuable for the development of conservation strategies.

Genetic diversity of Vriesea cacuminis (Bromeliaceae): an endangered and endemic Brazilian species

“…Individuals with identical ISSR markers (probably clones) in Population 1 (Peão) suggest that individuals isolated by short distances (<1 m) could be previously linked. This fact has also been reported for another species of the Bromeliaceae, Encholirium biflorum (Mez) Forzza, which possesses a clonal habit and occurs isolated or in small clumps spread out on sandy-rocky soil (Cavallari et al, 2006). However, these observations for E. biflorum and V. cacuminis may not be very common.…”

“…Considered as a rare, restricted and endemic species, V. cacuminis has a relatively high genetic diversity assessed by ISSR markers (PPB = 87% and I = 0.33%). Although higher genetic diversity has been mainly related to wider distributed species (Souza and Lovato, 2010), geographically restricted species have also shown relatively high diversity index (Cavallari et al, 2006;Huang et al, 2008). Consequently, these data provide evidence that other factors, in addition to geographical distribution, could contribute to maintain the variability in rare and restricted species.…”

Transferability and characterization of microsatellite markers in five Bromeliaceae species belonging to the subfamilies Pitcairnioideae and Bromelioideae

“…According to Cavallari et al (2006), preservation of the genetic diversity has become the main focus of most conservation programs and knowing the distribution of this diversity within and between natural populations is the first step. Understanding genetic variation within the populations of a given species is an essential prerequisite for conservation action , which is essential for the establishment of sustainable forms of economic exploitation.…”

“…Therefore, the use of molecular genetic markers to assess genetic diversity of populations plant species occurring in Atlantic Forest has been reported in several studies (Chen et al 2002, Boneth et al 2003, Cavallari et al 2006). Because of their greater convenience, the molecular markers most commonly used in analysis of genetic diversity in plants are polymerase chain reaction-based assays (PCR), particularly microsatellite or Simple Sequence Repeats (SSR) (Litt & Luty 1989), for they are a group of markers highly informative due to their multiallelic and codominant nature, reproducibility, heritability, relative abundance and extensive genome coverage , Yamamoto et al 2002.…”

Range-wide patterns of nuclear and chloroplast DNA diversity in Vriesea gigantea (Bromeliaceae), a neotropical forest species

“…Systematic relationships in the family are relatively well understood compared with most other neotropical plant families, and bromeliads are increasingly being studied by population geneticists interested in microevolution and speciation in the neotropics (for example, Sarthou et al, 2001;Cavallari et al, 2006;Barbará et al, 2007Barbará et al, , 2008. Bromeliads also show striking variation in breeding systems (from predominant inbreeding to predominant outcrossing), growth habits (epiphytic, terrestrial or saxicolous) and distributions (continuous forest species vs patchily distributed, rock-adapted 'inselberg' species).…”