Genetic variation within and among the wild populations of Alhagi graecorum using ISSR markers

Extra-floral nectaries (EFNs) are thought to represent protective adaptations against herbivory, but studies on the evolutionary ecology of EFNs have seldom been conducted. Here we investigate the patterns of natural selection and genetic variation in EFN traits in two wild populations of Anemopaegma album Mart. ex DC. (Bignoniaceae) that have been previously described as contrasting EFN – ant adapted localities in the Neotropical savanna (Cristália and Grão Mogol). In each population, four EFN descriptors, foliar damage, and reproductive success variables were measured per plant (100–120 plants per population). To estimate the heritability of EFN traits, we crossed reproductive plants in the field, and grew offspring plants in a common garden. The results showed that ant assemblages differed between populations, as did the range of foliar herbivory. Genetic variation and positive phenotypic selection in EFN abundance were only detected in the Cristália population, in which plants with more EFNs were more likely to reproduce. An evaluation of putative causal links conducted by path analysis corroborated the existence of phenotypic selection on EFNs, which was mediated by the herbivory process in the Cristália population. While EFNs could be currently under selection in Cristália, it is possible that past selection may have driven EFN traits to become locally adapted to the local ant assemblage in the Grão Mogol population.

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Evaluation of Genetic Variation Among Wild Populations and Local Varieties of Rice

Rice ◽

10.1007/s12284-011-9067-x ◽

2011 ◽

Vol 4 (3-4) ◽

pp. 170-177 ◽

Cited By ~ 11

Author(s):

Takashige Ishii ◽

Takashi Hiraoka ◽

Tomoyuki Kanzaki ◽

Masahiro Akimoto ◽

Rieko Shishido ◽

...

Keyword(s):

Genetic Variation ◽

Wild Populations ◽

Local Varieties

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Genetic variation in native and farmed populations of Tambaqui (Colossoma macropomum) in the Brazilian Amazon: regional discrepancies in farming systems

Anais da Academia Brasileira de Ciências ◽

10.1590/0001-376520130007 ◽

2013 ◽

Vol 85 (4) ◽

pp. 1439-1447 ◽

Cited By ~ 8

Author(s):

Jonas Aguiar ◽

Horacio Schneider ◽

Fatima Gomes ◽

Jeferson Carneiro ◽

Simoni Santos ◽

...

Keyword(s):

Genetic Diversity ◽

Genetic Variation ◽

Dna Sequences ◽

Amazon Basin ◽

Farming Systems ◽

Wild Populations ◽

The West ◽

Colossoma Macropomum ◽

Breeding Stock ◽

History Of

The tambaqui, Colossoma macropomum, is the most popular fish species used for aquaculture in Brazil but there is no study comparing genetic variation among native and farmed populations of this species. In the present study, we analyzed DNA sequences of the mitochondrial DNA to evaluate the genetic diversity among two wild populations, a fry-producing breeding stock, and a sample of fish farm stocks, all from the region of Santarém, in the west of the Brazilian state of Pará. Similar levels of genetic diversity were found in all the samples and surprisingly the breeding stock showed expressive representation of the genetic diversity registered on wild populations. These results contrast considerably with those of the previous study of farmed stocks in the states of Amapá, Pará, Piauí, and Rondônia, which recorded only two haplotypes, indicating a long history of endogamy in the breeding stocks used to produce fry. The results of the two studies show two distinct scenarios of tambaqui farming in the Amazon basin, which must be better evaluated in order to guarantee the successful expansion of this activity in the region, and the rest of Brazil, given that the tambaqui and its hybrids are now farmed throughout the country.

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