Vera L.P. Polez

• Brazilian Agricultural Research Corporation (EMBRAPA)

The growing demand for safe food associated with increased restrictions for the use of synthetic agrochemicals in different cultures has led to the development of more sustainable technologies for control of pests, such as phytonematodes. In this sense, natural products and residues are rich sources of compounds and nutrients that can contribute to...

Root-knot nematodes (Meloidogyne spp.) considerably affect their plant hosts, causing extensive damage in the world agriculture. The most widely used method to control these pathogens is through the intensive application of nematicides, despite being highly toxic to humans, animals, and the environment. The urgent search for alternative forms of co...

Green nanotechnology is a recent branch of nanotechnology in consonance with current concerns about sustainability issues using methods and materials that aim to generate eco-friendly nanosystems, with low environmental impact associated with significant economic and social gains. This concept offers opportunities for the use of nontoxic reagents a...

Green synthesis of silver nanoparticles (AgNPs) is already widely used, however, it presents challenges. This work describes a way to modulate the physicochemical characteristics of AgNPs using green synthesis and aqueous extract from different parts of Handroanthus heptaphyllus. The progress of the synthesis reaction, the physicochemical character...

Current antifungal drugs present poor effectiveness and there is no available vaccine for fungal infections. Thus, novel strategies to treat or prevent invasive mycosis, such as cryptococcosis, are highly desirable. One strategy is the use of immunomodulators of polysaccharide nature isolated from mushrooms. The purpose of the present work was to e...

Meloidogyne incognita is responsible for significant crop losses worldwide. The main strategy to control this phytopathogen is still based on synthetic nematicides that are harmful to human health and the environment. In this context, aqueous seed extracts of antagonistic plants were screened for molecules effective toward the infective stage (J2)...

The approaches for synthesis of metal nanoparticles (MNPs) through green chemistry methods have become a recent trend of studies that focus on sustainability and innovation. Fungi are among the many groups of living organisms that have been known as useful for the synthesis of MNPs and there are many advantages of their use over other organisms sin...

A família Tephritidae (Diptera) comporta algumas das moscas consideradas de maior importância econômica na fruticultura brasileira. A espécie Ceratitis capitata, junto a outras espécies do gênero Anastrepha, ocupa lugar de destaque dentre os tefritídeos relevantes para a economia do país. Estudos moleculares com o DNA de indivíduos dessas espécies...

RESUMO Visando à otimização da diagnose molecular de plântulas de cana-de-açúcar, tentou-se desen-volver iniciadores específicos para escaldadura e ferrugem alaranjada, assim como a comparação da PCR comum e a PCR em Tempo Real (PCR/TR) de maior resolução, importante para doenças com grande período de latência, como as causadas por: 1-Bactérias, (a...

Atualmente, a ferrugem alaranjada é a mais nova doença na cultura de cana-de-açúcar, causada pelo basidiomiceto Puccinia kuehnii. Nas regiões onde ocorre esse tipo de ferrugem, o controle é feito basicamente com o plantio de cultivares resistentes, porque o uso de fungicidas não é considerado prático e nem econômico. Além da ferrugem alaranjada, a...

The pollution of the aquatic ecosystem has been increasing in the last years, mainly due to the industrial and agricultural development. The Atrazine pesticide is an important agent pollutant and it can harm the development and reproduction of several species of fish due to its toxicity. Piaractus mesopotamicus (pacu) is one of the species thorough...

The pollution of the aquatic ecosystem has been increasing in the last years, mainly due to the industrial and agricultural development. The Atrazine pesticide is an important agent pollutant and it can harm the development and reproduction of several species of fish due to its toxicity. Piaractus mesopotamicus (pacu) is one of the species thorough...

Study of alterations in the concentration of ions in the plasma and of the induction of micronucleus in Piaractus mesopotamicus exposed to the herbicide atrazine The pollution of the aquatic ecosystem has been increasing in the last years, mainly due to the industrial and agricultural development. The Atrazine pesticide is an important agent pollut...

Hemolytic anemia accompanied by changes in the immunology system is one of the sulfide intoxication harmful effects on Hoplosternum littorale. Hematological parameters are considered as effective indicators of stress caused by this hydrogen sulfide. During sulfide exposure, H. littorale neither alters the methemoglobin concentration nor forms sulfh...

Increased environmental pH decreases ammonia transport through the gills, impairing nitrogenous waste. The consequent toxicity is usually drastic to most fishes. A few species are able to synthesize urea as a way to detoxify plasma ammonia. We studied three teleosts of the family Erythrinidae living in distinct environments, and assumed the biochem...

The non-ionized form of ammonia is very toxic to many aquatic species. It is especially important in several aspects of fish biology. A large range of organismal strategies for coping with environmental stressors is usually observed in living organisms. Among those, the responses for managing chemical stressors are well studied. The present work co...

The exposure of fish to air is normally expected to interfere with the nitrogen excretion process. Hoplias malabaricus and Hoplerythrinus unitaeniatus, two teleost species, display distinct behaviors in response to decreases in natural reservoir water levels, although they may employ similar biochemical strategies. To investigate this point, plasma...

Juvenile tambaqui, Colossoma macropomum, were exposed to sulfide and hypoxia for 12, 24, 48 and 96 h. Hemoglobin concentrations, red blood cell counts, and mean cell hemoglobin, were higher at 12 h in fish exposed to hypoxia. However, control fish and those exposed to sulfide and hypoxia had lower red blood cell count, hemoglobin concentration and...