William Pietro-Souza

Características morfológicas e produtivas de feijão guandu anão cultivado em solo compactado

Aliado ao uso indiscriminado de maquinarios agricolas, o manejo inadequado altera a densidade natural do solo causando reducao em sua qualidade fisica e, por conseguinte, implicando em efeitos negativos no desenvolvimento de culturas. Assim, objetivou-se avaliar a influencia de compactacao do solo nas caracteristicas morfologicas e produtivas de feijao guandu anao (Cajanus cajan L. Mill sp.) cv. IAPAR 43 Arata. O experimento foi realizado em casa de vegetacao na Universidade Federal de Mato Grosso - Campus Universitario de Rondonopolis. Utilizou-se um Latossolo Vermelho coletado na profundidade de 0-20 cm. Os tratamentos foram cinco niveis de compactacao (densidades do solo: 1,0; 1,2; 1,4; 1,6 e 1,8 Mg m-3) e seis repeticoes em delineamento experimental inteiramente casualisado. As avaliacoes foram realizadas aos 33 e 63 dias apos a emergencia das plantas, determinando-se numero de ramos, numero de folhas, altura de plantas, diâmetro do caule, producao de massa seca de folhas, colmos, parte aerea e raiz. As caracteristicas morfologicas e produtivas do feijao guandu anao apresentam restricoes quanto aos niveis de compactacao do solo, mostrando-se pouco eficiente na descompactacao em Latossolo Vermelho.

Fish from urban tributaries to the Vermelho River, upper Paraguay River Basin, Mato Grosso, Brazil

The fish fauna of urban streams is still poorly known, it difficult to assess the effects of urbanization expansion on fish species composition, for this reason the aim of this study was to provide a checklist of species that compose the ichthyofauna of six urban streams, tributaries to the Vermelho River, upper Paraguay River Basin, Rondonopolis, Mato Grosso State, Brazil. The samples were performed with seine nets on a spatial gradient of 75 m, and with sieves for a period of 15 minutes in each site. A total of 56 species belonging to five orders, Characiformes, Siluriformes, Gymnotiformes, Cyprinodontiformes, and Perciformes, 21 families and 44 genera were sampled. The most common species were Astyanax asuncionensis Gery, 1972, Astyanax abramis (Jenyns, 1842), Odontostilbe pequira (Steindachner, 1882), Odontostilbe paraguayensis Eigenmann & Kennedy, 1903 , Characidium zebra Eigenmann, 1909 and Hypostomus sp. This checklist brings additional knowledge on fish that inhabit tributaries to the major rivers of northern Pantanal.

Endophytic fungal communities of Polygonum acuminatum and Aeschynomene fluminensis are influenced by soil mercury contamination

The endophytic fungal communities of Polygonum acuminatum and Aeschynomene fluminensis were examined with respect to soil mercury (Hg) contamination. Plants were collected in places with and without Hg+2 for isolation and identification of their endophytic root fungi. We evaluated frequency of colonization, number of isolates and richness, indices of diversity and similarity, functional traits (hydrolytic enzymes, siderophores, indoleacetic acid, antibiosis and metal tolerance) and growth promotion of Aeschynomene fluminensis inoculated with endophytic fungi on soil with mercury. The frequency of colonization, structure and community function, as well as the abundant distribution of taxa of endophytic fungi were influenced by mercury contamination, with higher endophytic fungi in hosts in soil with mercury. The presence or absence of mercury in the soil changes the profile of the functional characteristics of the endophytic fungal community. On the other hand, tolerance of lineages to multiple metals is not associated with contamination. A. fluminensis depends on its endophytic fungi, since plants free of endophytic fungi grew less than expected due to mercury toxicity. In contrast plants containing certain endophytic fungi showed good growth in soil containing mercury, even exceeding growth of plants cultivated in soil without mercury. The data obtained confirm the hypothesis that soil contamination by mercury alters community structure of root endophytic fungi in terms of composition, abundance and species richness. The inoculation of A. fluminensis with certain strains of stress tolerant endophytic fungi contribute to colonization and establishment of the host and may be used in processes that aim to improve phytoremediation of soils with toxic concentrations of mercury.

CHUVA DE SEMENTES EM REMANESCENTES FLORESTAIS DE CAMPO VERDE, MT

The objective of this study consists in evaluating seasonally the seeds production from forest fragments located in rural zone of Campo Verde, MT. This characterization occurred in terms of seed production and plant species richness. Three forest fragments characterized as semidecidual stational forest were selected. In each fragment five collectors were installed and made with PVC pipes (1 m2; nylon mesh of 0.001 m and 0.15 m depth of the bulge). The material was monthly collected, and the seeds were quantified, and separated according to the sort of dispersal, successional stage and form of life. It was determined the density, absolute frequency, diversity index and equitability. Altogether 3,622 seeds were collected, belonging to 74 taxa. The highest densities of seeds were observed during the months of September, October and November. Lianas Gouania sp., Fridericia speciosa, Heteropterys sp. and Distictella sp. responded with 55.95% of total collected seeds. From all the species that composed the seed rain, 74% are not dispersed by wind. However, when the amount of diaspores collected was checked, forms dispersed by wind were predominant, representing 76% of total. It may be cited as important arboreal taxons for reforestation in the region of Campo Verde, located at southeast of Mato Grosso: Tachigali rubiginosa, Siparuna guianensis, Nectandra sp., Cordia alliodora, Alibertia sp., Terminalia brasiliensis and Myrcia sp. These species should be targeted for more specific studies related to their potential for recovery of degraded environments, considering permanent preservation areas and legal reserves.