Renata Gomes de Souza

Intraornatosporaceae ( Gigasporales ), a new family with two new genera and two new species

A new family (Intraornatosporaceae), two new genera (Intraornatospora, Paradentiscutata), two new species (P. bahiana, P. maritima), and a new combination (I. intraornata) are presented in the Gigasporales. The genera, both with diagnostic introverted ornamentations on the spore wall, are distinguished by spore wall structure and germ shield characteristics. The new species, detected in NE Brazil, can be differentiated by their projections on the outer spore surface. Partial sequences of the LSU rRNA gene place both species next to I. intraornata in a monophyletic major clade related to Gigasporaceae and Dentiscutataceae.

Arbuscular mycorrhizal fungi in a semi-arid, limestone mining-impacted area of Brazil

The main goal of this study was to determine the diversity and activity of arbuscular mycorrhizal fungi (AMF) in an area degraded by limestone mining within the semi-arid region of Brazil known as the caatinga (shrublands). Near a limestone quarry, we selected two areas of caatinga (preserved and degraded) for study. The number of glomerospores did not differ significantly between the two areas. There was a trend toward the most probable number of infective propagules being higher in the degraded area. Twenty AMF taxa were identified in the two sampled areas, species richness, diversity and evenness being higher in the preserved area. Two species of Racocetra represent new records for the semi-arid region of Brazil. Glomerospore production and AMF species richness were unaffected by mining activity in the study area.

O papel da comunidade de fungos micorrízicos arbusculares (FMA) autóctones no desenvolvimento de espécies vegetais nativas em área de dunas de restinga revegetadas no litoral do Estado da Paraíba

Association of arbuscular mycorrhizal fungi (AMF) and plant roots constituted one of the most important ways to mitigate the impact of disturbed area. The aim of this work was to characterize the AMF community in the soil from revegetated dune area and to analyze its influence on the native plant development. Soils were collected in rainfall season in the revegetated area. Glomalin-related soil protein production (GRSP), glomerospores density and diversity were evaluated. The influence of AMF autoctone community was determined for two native plants: Tabebuia roseo-alba (Ridl.) Sandw. (peroba) and Tocoyena selloana Schum. (jenipapo-bravo). Experimental design for each species was completely randomized with 10 replicates, two treatment - native soil (SN) and disinfested native soil (SND) - were tested. Parameters evaluated were: height, shoot diameter, leaf number and area, shoot and root dry mass, nutrient contents, glomerospore density, mycorrhizal colonization and glomalin-related soil protein production (GRSP). In dune revegetated soil was found 1 glomerospore g-1 soil and 1.20 ± 0.04 mg GRSP g-1 soil, and six AMF species were identified. Native soil promoted more development to plant and fungi. Mycorrhizal colonization in peroba was 80% and in jenipapo-bravo 60%. Then, AMF are present in revegetated area after mining contributing to growth of native plant species studied in greenhouse conditions, suggesting that their performance is affected by arbuscular mycorrhiza symbiosis.