Controle alternativo de Planococcus citri (Risso, 1813) com extratos aquosos de pinhão-manso / Alternative control Planococcus citri (Risso, 1813) with aqueous extracts of Jatropha

A cochonilha-da-roseta, Planococcus citri (Risso, 1813) (Hemiptera: Pseudococcidae), constitui um problema fitossanitário na cultura do café. O controle mais usual dessa praga é o químico, o que pode acarretar, além de problemas socioambientais, a seleção de indivíduos resistentes. Com isso, torna-se necessário o controle alternativo. Dessa forma, o objetivo deste trabalho foi estudar, em condições de laboratório, o potencial inseticida de diferentes partes da planta de Jatropha curcas , em variadas concentrações, sobre P. citri . Discos de folhas de café conilon com 10 cochonilhas (ninfas e adultos) foram pulverizados direta e indiretamente com auxílio da torre de Potter, com pressão de 15 Lb/pol2, aplicando 6 mL de solução por repetição. Testaram-se sete concentrações do óleo e de extratos, tanto na aplicação direta quanto na indireta, com 10 repetições por tratamento, sendo avaliada a mortalidade em função do tempo. Todas as estruturas de pinhão-manso, em ambas as vias de aplicação, apresentaram índices de mortalidade satisfatórios de P. citri , alcançando 91,6% de mortalidade nas concentrações de 1,5, 2,0 e 3,0% do óleo na aplicação direta.(AU)

The Planococcus citri (Risso, 1813) (Hemiptera: Pseudococcidae) is a phytosanitary problem in the coffee's cultivation. The most used type of control for this pest is the chemical one, which leads to the selection of resistant individuals, as well as social and environmental problems. Therefore, it is necessary to control the alternative. Thus, this paper had the aim of studying the potential insecticide in different parts of the plant Jatropha curcas , in some concentrations, over the P. citri . Dices of leaf containing 10 P. citri (nymphs and adults) were directly and indirectly sprayed with the Potter Tower's assistance, on the pressure at 15 Lb/pol2, applying 6 mL of solution per repetition. Seven concentrations of oil and extracts were tested, and the mortality was evaluated in function of time. All physic nut's structures in both routes of administration showed satisfactory mortality P. citri , reaching 91.6% mortality at the concentrations of 1.5, 2.0 e 3.0% oil in the direct application.(AU)

A survey of mealybugs infesting South-Brazilian wine vineyards

ABSTRACTMealybugs (Hemiptera: Pseudococcidae) are important pests of the grapevine Vitis spp. and are responsible for direct and indirect damage to production. The main mealybug species present in wine grapevine (Vitis vinifera L.) in Southern Brazil were identified and their incidence evaluated. Bunch-samples (n = 50) from 131 vineyards located in the Serra Gaúcha Region (RS) of Brazil were analyzed at harvest, and the occurrence of mealybugs in the roots was evaluated at the time of eradication of plants for replanting. Mealybugs were reared in laboratory until adulthood for species determination. The species Dysmicoccus brevipes (Cockerell, 1983), Dysmicoccus sp., Planococcus citri (Risso, 1813), Pl. minor(Maskell, 1897), Pseudococcus viburni (Signoret, 1875) and Pseudococcus sp. were identified in bunches. Dysmicoccus sp., D. umbambae Granara de Willink, 2009, Pl. citri and Pseudococcus sp. were found in the roots. Pl. citri (31.4%) and Dysmicoccus sp. (22.7%) were the most common species found in wine grape bunches in the Serra Gaúcha Region.

Sobre a nomenclatura das espécies de cochonilhas-farinhentas do cafeeiro nos Estados de Minas Gerais e Espírito Santo / About the nomenclature of coffee mealybug species in Minas Gerais and Espírito Santo States, Brazil

Root coffee (Coffea arabica L.) mealybugs (Hemiptera: Pseudococcidae) collected in Boa Esperança, southern Minas Gerais State, were identified as Dysmicoccus texensis (Tinsley) (= bispinosus Beardsley) and these from aerial part collected in Castelo, State of the Espírito Santo, as Planococcus minor (Maskell). However, Brazilian literature mentions other mealybug species of coffee tree as Pseudococcus cryptus Hempel in roots and Planococcus citri (Risso) in the aerial part. Therefore, more than one mealybug species may be occurring in the roots as in aerial part of coffee trees, and the survey and taxonomic studies are necessary before setting a control program, specially biological control.

Cochonilhas-farinhentas (Hemiptera: Pseudococcidae) das raízes do cafeeiro (Coffea arabica L.) coletadas em Boa Esperança, Estado de Minas Gerais, foram identificadas como Dysmicoccus texensis (Tinsley) (= bispinosus Beardsley) e da parte aérea dos cafeeiros em Castelo, Estado do Espírito Santo, como Planococcus minor (Maskell). Porém, na literatura brasileira são citadas outras espécies de pseudococcídeos em cafeeiros, Pseudococcus cryptus Hempel nas raízes e Planococcus citri (Risso) na parte aérea. Assim, é possível que mais de uma espécie de cochonilhas-farinhentas possam estar ocorrendo nas raízes e na parte aérea dos cafeeiros, tornando os levantamentos e estudos taxonômicos necessários para o estabelecimento de programas de controle, sobretudo o biológico.

Isolation and identification of Micrococcus roseus and Planococcus sp from Schirmacher oasis, Antarctica.

Five cultures isolated from soil samples collected in Schirmacher oasis, Antarctica, have been identified as members of the family Micrococcaceae, with 3 belonging to the genus Micrococcus and two to Planococcus. The 3 Micrococcus isolates (37R, 45R and 49R) were red-pigmented and h a d ~ 75 mol% G + C in their DNA; they were identified as Micrococcus roseus. The two Planococcus isolates (30Y and Lz3OR) were yellow and orange in colour, and had 43·5 and 40·9 mol % G + C in their DNA respectively; they were identified as Planococcus sp.

The mealybug chromosome system I: Unusual methylated bases and dinucleotides in DNA of a Planococcus species.

The methylation status of the nuclear DNA from a mealybug, a Planococcus species, has been studied. Analysis of this DNA by High Performance Liquid Chromatography and Thin Layer Chromatography revealed the presence of significant amounts of 5- methylcytosine. Since analysis of DNA methylation using the Msp I/Hpa II system showed only minor differences in susceptibility of the DNA to the two enzymes, it seemed possible that 5-methylcytosine (5mC) occurred adjacent to other nucleotides in addition to its usual position, next to guanosine. This was verified by dinucleotide analysis of DNA labelled in vitro by nick translation. These data show that the total amount of 5-methylcytosine in this DNA is slightly over 2.3 mol %, of which 0.61% occurs as the dinucleotide 5mCpG, 0.68% as 5mCpA, 0.59% as 5mCpT and 0.45% as 5mCpC. 5mCpG represents approximately 3.3% of all CpG dinucleotides. The experimental procedure would not have permitted the detection of 5mCp5mC, if it occurs in this system. Unusually high amounts of 6-methyladenine (approximately 4 mol %) and 7-methylguanine (approximately 2 mol %) were also detected, 6-methyladenine and 7-methylguanine occurred adjacent to all four nucleotides. The total G+C content was 33.7% as calculated from dinucleotide data and 32.9% as determined from melting profiles.