ABSTRACT
The mosquito Stegomyia aegypti (=Aedes aegypti) (Diptera: Culicidae) is a vector for the dengue and yellow fever viruses. As blood digestion occurs in the midgut, this organ constitutes the route of entry of many pathogens. The effects of the insecticide imidacloprid on the survival of St. aegypti were investigated and the sub-lethal effects of the insecticide on midgut development were determined. Third instar larvae were exposed to different concentrations of imidacloprid (0.15, 1.5, 3.0, 6.0 and 15.0 p.p.m.) and survival was monitored every 24 h for 10 days. Midguts from imidacloprid-treated insects at different stages of development were dissected and processed for analyses by transmission electron microscopy, immunofluorescence microscopy and terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assays. Imidacloprid concentrations of 3.0 and 15.0 p.p.m. were found to affect midgut development similarly. Digestive cells of the fourth instar larvae (L4) midgut exposed to imidacloprid had more multilamellar bodies, abundantly found in the cell apex, and more electron-lucent vacuoles in the basal region compared with those from untreated insects. Moreover, imidacloprid interfered with the differentiation of regenerative cells, dramatically reducing the number of digestive and endocrine cells and leading to malformation of the midgut epithelium in adults. The data demonstrate that imidacloprid can reduce the survival of mosquitoes and thus indicate its potentially high efficacy in the control of St. aegypti populations.
Subject(s)
Aedes/drug effects , Imidazoles/pharmacology , Insecticides/pharmacology , Nitro Compounds/pharmacology , Aedes/growth & development , Aedes/physiology , Animals , Female , Larva/drug effects , Larva/growth & development , Larva/physiology , Longevity/drug effects , NeonicotinoidsABSTRACT
O noni é uma cultura de origem asiática que vem despertando interesse de agricultores brasileiros em virtude de suas propriedades fitoterápicas na medicina popular e de seu elevado valor comercial; contudo, são escassas as informações quanto ao manejo da cultura em geral e inexistentes estudos a respeito da irrigação da cultura no Brasil. Objetivou-se com este estudo definir, entre dois sistemas de irrigação e cinco laminas d´água, qual a melhor condição para o desenvolvimento vegetativo da cultura. O experimento foi realizado no período de maio de 2009 a março de 2010, em Trairi-CE. Utilizou-se o delineamento experimental de blocos casualizados e dois sistemas de irrigação localizada (gotejamento e microaspersão) dispostos em faixas verticais. Dentro de cada faixa foram distribuídos os blocos com as parcelas dos cincos níveis de irrigação correspondentes à aplicação de frações da evapotranspiração de referência FAO (ETo) de 40%, 60%, 80% 100% e 120%. Para o sistema de irrigação por microaspersão as lâminas correspondentes foram: 109,3 mm, 135,8 mm, 187,9 mm, 227,8 mm e 297,7 mm e para sistema de irrigação por gotejamento: 83,4 mm, 1237 mm, 166,5 mm, 204,7 mm e 254,4 mm, respectivamente. Foram utilizadas cinco repetições. O desenvolvimento vegetativo de plantas de noni foi influenciado tanto pelos sistemas de irrigação, quanto pelas lâminas d´água aplicadas. A lâmina de irrigação equivalente a 227,8 mm, correspondente a 100% da ETo, na irrigação por microaspersão, proporcionou maiores ganhos de diâmetro do coleto, altura da planta, e diâmetro de copa.
Noni is a crop of Asian origin that has piqued the interest of Brazilian farmers because of its properties in herbal folk medicine and its high commercial value. However, there is little information about the crop management in general, and particularly on the irrigation of the crop in Brazil. The objective of this study was to define what localized irrigation system (drip or micro sprinklers) and water depth that provide the best vegetative growth of noni plants. The experiment was conducted from May 2009 to March 2010 in the city of Trairi, Brazil. We used a split block experimental design, with two irrigation systems (drip and micro sprinklers) arranged in vertical lines. Within each line, five irrigation levels, corresponding to the application of fractions of the reference evapotranspiration (ETo) 40% 60% 80% 100% and 120%, were distributed in five blocks. For the micro sprinkler irrigation system, the corresponding slides were: 109.3 mm, 135.8 mm, 187.9 mm, 227.8 mm and 297.7 mm, respectively, and for the drip irrigation system, they were: 83.4 mm, 123.7 mm, 166.5 mm, 204.7 mm and 254.4 mm, respectively. The noni vegetative growth was influenced both by the irrigation systems and the depths of irrigation applied. The application of irrigation depths equivalent to 227.8 mm, which corresponds to 100% of ETo with the use of micro sprinklers, provided the largest gains in stem diameter, plant height and canopy diameter.
Subject(s)
Morinda/growth & development , Agricultural Irrigation/methods , Plant DevelopmentABSTRACT
Necrotizing fasciitis is an often fatal, often initially unrecognized condition. Although it was first described over 60 years ago, occurrence in the vulva was only first recognized in 1972. The condition is most often associated with diabetes, prior injury, surgery, or irradiation. Aggressive surgical excision is required, early in the course of the disease, to salvage the patient. An association with vulvar carcinoma in a nondiabetic patient has not been previously reported. We report such a case, with a poor outcome, because surgical intervention was not possible until late in the course of the disease.
