A new microsporidian parasite of the genus Amblyospora (Hazard and Oldacre, 1975) identified from the halophilic mosquito Ochlerotatus detritus (Haliday, 1833) (Diptera: Culicidae) through rDNA ITS sequencing

Ochlerotatus detritus (Haliday, 1833) from Parkgate marshes, Wirral, UK are shown to be parasitised by a new species of Amblyospora (Hazard and Oldacre, 1975) microsporidian. Phylogenetic analysis shows that Internal Transcribed Spacer sequences from this microsporidian are distinct from those of all known microsporidia identified to date, but form a clade with Amblyospora weiseri Lukeš and Vávra, 1990 and A. stictici Andreadis, 1994, microsporidia identified from Ochlerotatus cantans Meigen, 1818 and O. sticticus Meigen, 1838, respectively. Prevalence rates, from pooled samples (N = 5 per pool) were low (2.37%; lower limit 0.78%, upper limit 5.62%), which may be a consequence of these ephemeral brackish water pool habitats periodically drying out. There is increasing interest in the use of microsporidian parasites as novel vector control strategies and understanding the phenology of this microsporidian and its mosquito host may ultimately lead to new methods of control for this nuisance biting species

Glifosato aplicado com diferentes concentrações de uréia ou sulfato de amônio para dessecação de plantas daninhas Glyphosate applied with different concentrations of urea or ammonium sulfate for weed desiccation

Este trabalho foi desenvolvido com o objetivo de avaliar a eficácia do herbicida glifosato, para a dessecação de trapoeraba (Commelina benghalensis) e outras plantas daninhas, quando combinado a diferentes concentrações de sulfato de amônio ou uréia. Foram conduzidos três experimentos com tratamentos semelhantes: dois em campo e um em casa de vegetação. Os tratamentos aplicados em campo foram: glifosato (360 g ha-1 de e.a.), isolado ou acrescido de quatro concentrações de sulfato de amônio (2,5, 5, 10 e 20 g L-1) ou uréia (1,5, 3, 6 e 12 g L-1); glifosato a 720 g ha-1 de e.a., aplicado isoladamente; e testemunha sem aplicação. Em casa de vegetação, para o controle específico da trapoeraba, as doses de glifosato foram elevadas para 720 (isolado e nas combinações) e 1.440 g ha-1 de e.a. A adição de sulfato de amônio à calda do glifosato elevou o controle das plantas daninhas em campo, para as concentrações com até 10 g L-1. O herbicida glifosato não foi eficaz no controle da trapoeraba, em nenhumas das doses usadas. A adição de uréia não promoveu incrementos de controle em condição de campo; porém, para concentrações de até 6 g L-1, melhorou o controle da trapoeraba, na avaliação conduzida aos 28 dias após aplicação.<br>This work was developed with the objective of evaluating glyphosate efficacy for Bengal dayflower (Commelina benghalensis) and other weeds desiccation, when combined to different concentrations of ammonium sulfate or urea. Three experiments were carried out with similar treatments: two in field conditions and one in greenhouse. Treatments applied in field conditions were: glyphosate at 360 g ha-1 a.e., isolated or combined to four concentrations of ammonium sulfate (2.5, 5, 10, and 20 g L-1) or urea (1.5, 3, 6, and 12 g L-1); glyphosate at 720 g ha-1 a.e., applied isolately; and checks without application. In greenhouse, for the specific control on Bengal dayflower, glyphosate rates were increased to 720 (isolated or in combination) and to 1,440 g ha-1 a.e. Ammonium sulfate addition to glyphosate spray solution increased field weed control, when concentrations up to 10 g L-1 were used. None of the glyphosate rates were efficient to control Bengal dayflower. Urea addition to spray solution did not improve weed control in field conditions; however, it increased Bengal dayflower control for concentrations up to 6 g L-1, at the evaluation after 28 days of application