caracterização in situ e estrutura genética de populações de Gossypium mustelinum

Gossypium mustelinum Miers ex Watt is the only cotton species native from Brazil. It is endemic of the semi-arid region from North-east of the country, where it occur near from resilient water sources. The threats to the in situ conservation of the populations are caused by human interference in its habitat, mainly by excessive cattle graze and deforestation. Establish efficient strategies of in situ conservation depend on the accomplishment of a diagnosis of how the specie is found in its natural environment, and the knowledge about the genetic structure of the populations. The objectives of this work were i) to determine the in situ conditions of two populations present in rivers from basin of Rio Paraguaçu at the Bahia State, ii) to evaluate the structure and genetic variability presented in both populations, iii) to establish in situ and ex situ conservation strategies. It were realized collection in november 2007, when was realized in situ characterization of G. mustelinum. SSR markers were used for analyze 218 genotypes deriving from two populations of the G. mustelinum, localized at Tocó river and the Capivara river. The allelic frequencies, the heterozigosity and the F statics were estimated. All the plants were classified as wild and natives, and there was no evidence of the use the plants or its parts. The populations showed different conservation conditions in situ. Few plantlets were found in sites with excessive cattle feed, an indication that the damages in young plants should be high enough to compromise the renovation of the populations. On the other hand, populations were well preserved when the anthropic damages was low or inexistent. The 14 SSR primer pairs amplified 17 loci with a medium number of 5 alleles per locus (a total of 85 alleles). The high level of endogamy estimated (FIS=0,808) and the low observed heterozygosity (H0=0,093) were indicatives that the populations reproduce mainly by selfing, geitonogamy and crosses between related individuals. The genetic diversity was high (HE=0,482) and the differentiation between the populations was very high (FST=0,328). At least two sites from both populations of G. mustelinum must be preserved to achieve suitable in situ conservation. Actions that preserve the gallery forest and keep the cattle away should implemented, and could be as simple as erecting a fence. It is not possible anticipated if the in situ preservation will be possible. Therefore collections and ex situ preservation of representative specimens are essential to conserve the genetic diversity of native G. mustelinum

Diretrizes para conservação da espécie Mimosa Caesalpiniifolia Benth., Macaíba-RN

About 40% of the earth is occupied by tropical and subtropical forests, including 42% of dry forests, where there is Caatinga Bioma, contemplating tree forests and shrubs, with xerophytic characteristics. Study and conservations of Caatinga biologic diversity is one of the greatest challenges of Brazilian science because those are, proportionally, the less studied among natural areas, with most of the scientific effort centered in very few points around the main cities in the area and also because it is the less protected natural Brazilian area. The environmental degradation is constantly increasing and has its rhythm accelerated by the men appropriation to meet or not their own needs. Therefore, species conservation should be based in three principles: the use of natural resources by present generation, waste prevention and use of the natural resources to benefit the majority of the citizens. Among the strategies to species conservation, we can mention the ex situ conservation , in which the conservation of genetic resources may be realized outside of the natural environment in which the species occur, and in situ conservation , or, in other words, in the places where the species occur. In ex situ conservation, the germplasm collections are maintained in the field and/or in laboratories (conservation chambers), and this mainly conserves intraspecific diversity (genetic variance), the ex situ collections are continuously enriched by collection activities, introduction and germplasm interchange; the in situ conservation preserving ecosystems and habitats, maintaining and recovering native population of species of interest. So, the objective of this paper is the search for strategies to the conservation of Mimosa caesalpiniifolia B. (sabiá) using instruments of environmental perception and plant biotechnology, as mechanisms of in situ and ex situ conservation. To environmental perception, were realized open, semi-structured and qualitative interviews. The questions included socioeconomic data and knowledge of Sabiá specie. To plant biotechnology, Sabiá seed collection were realized in different location to formation of a germplasm bank. The specie micropropagation was made from nodal segment of plants from the matrizeiro. About the knowledge of rural populations and the use of Sabiá plant, some preferences occurred from speeches that the plant possesses a firm wood, not attacked by termites, legalized for exploration by the Brazilian environmental organ (IBAMA), and is a native specie. This research found the rural population has knowledge about Sabiá specie and the natural resources are exhausting. The proposal that the rural community brought was the donation of the Sabiá specie seeding initiating on the rain season, in which the seeding would be plated between the lots, in individual plantations. To the formation of a matrix bank, plant biothecnology brought answers favorable to Sabiá specie seeding, with the formation of multiple shoots

Caracterização in situ e diversidade genética de algodoeiros mocós (Gossypium hissutum raça marie galante) da Região Nordeste do Brasil

Brazil is one of the major centers of diversity for polyploid cotton plants; these plants belong to the genus Gossypium, which has three known species: G. hirsutum, G. barbadense and G. mustelinum. The Northeast is the only region where the three species occur, the last group being endemic. Northeast s cotton plants can be important sources of variability for genetic breeding. It is believed that great part of local diversity is being lost, due to economic, political, cultural and agricultural problems. In an attempt to mitigate this loss and delineate conservation strategies it is necessary to know how the species are found where they occur. The objective was to characterize and determine how plants are maintained in situ in the states of Maranhão, Piauí, Ceará, Rio Grande do Norte and Paraíba at the beginning of the XXI century. The in situ characterization of G. hirsutum and G. barbadense was conducted through structured interviews with the cotton plants owners and through the analysis of the environment. The data were collected during expeditions undertaken between the years 2004 to 2005. Twenty-two plants were collected in the state of Paraíba, forty-four in the state of Rio Grande do Norte, one hundred and forty-six in the state of Ceará, forty in the state of Maranhão and ninety-one plants in the state of Piauí. All plants collected in the states of Paraíba and Rio Grande do Norte belonged to moco type. Moco cotton plants also predominated in the other states, representing 92%, 62% and 78% of plants collected in Ceará, Piauí and Maranhão, respectively. The other cotton plants collected belong to the species G. barbadense. The cotton plants were found in situ as dooryard plants, roads side, feral populations, cultivation or local varieties. Great part were dooryard plants (45.2%), being major in Piauí and Maranhão. Cultivation predominated in Ceará; in Rio Grande do Norte feral populations were the most frequent and, in Paraíba, local varieties. The maintenance of moco plants is related, mainly, to the phytotherapic domestic use (20.9%) and to confection of lamp wicks (29.7%). Few inhabitants in Paraíba, Rio Grande do Norte, Piauí and none in Maranhão used harvest the plants, storage the seeds or gin; however, in Ceará, 40.5% of owners affirmed that they harvested and commercialized the fiber. It was found that the maintenance of species is dependent of the fragile cultural habits of local inhabitants, therefore the maintenance in situ is not a suitable way to conservation of genetic resources. The efforts must be directed to the continuity of collections, maintenance and characterization ex situ

Caracterização genética e in situ de Gossypium barbadense na região norte do Brasil

Brazil has been considered one of the diversity centers of Gossypium barbadense species. It is believed that a relatively big erosion genetic process occurs with the species, due to economic, cultural and agricultural problems. A local diagnostic about species situation is the first step for reducing the diversity loss and establishing conservation strategies in situ. This research aimed the identification of the presence of Gossypium populations, characterization, determination of the main risks and collection of the accesses to store in germoplam banks, in Para and Amapa States. Expeditions were conducted in November 2004. An interview was carried out with the plant proprietor for characterizing in situ of G. barbadense species and of the environment where the plants were inserted. On hundred seventy nine plants in 22 municipal districts were collected in Para State and 117 plants in nine municipal districts in Amapa State. The majority of plants belong to G. barbadense species (98% in Amapa and 94% in Para). Plants occur in back yards, beside roads and spontaneously. That ones from back yards were more abundant (97% in Amapa and 95% in Para) and maintained as medicinal plants as the principal reason. Plants in natural environments in both states evaluated were not found, therefore, the creation of reserves and the application of others conventional methods of maintenance in situ are not applicable. The plant proprietors do not use to store or process seeds. Seed storage was reported as a practice by only 1% of the plant proprietors from Para and 11% from Amapa. The most plants collected were from two to three years of age (58% in Amapa and 93% in Para). As conclusions G. barbadense is the species most spread in the two studied states and are found in back yards. In Amapa State the botanical variety barbadense or Quebradinho is predominant, whereas in Para State the predominant variety is brasiliense or Rim-de-boi. Adequate conservation of thestudied species must be carried out in germoplasm collections maintained ex situ