Showing papers by "Universidade Federal de Viçosa published in 1993"

High‐Altitude bee fauna of southeastern Brazil: Implications for biogeographic patterns (Hymenoptera: Apoidea)

Abstract: The bee fauna of two high altitude areas in southeastern Brazil is compared to that of surrounding lowlands. Four different geographic distribution patterns are recognized: species may be a) widespread in the region regardless of altitude; b) widespread in the lowland but not reaching altitudes above around 1300 m; c) restricted to the mountains of southeastern Brazil; or d) common to these mountains and to mountains and/or lowlands south of about 24’ latitude south. This last set of species may be a remnant fauna associated with the subtropical and temperate vegetation that advanced northward in cold periods. This relict fauna may be descendant of populations that have been trapped on the top of mountain ranges by the development of a warmer climate. It is also suggested that a relationship may exist between the bee fauna of the southeastern mountains fields and that of the “cerrado”; and related vegetations.

A new heterochromatin banding pattern revealed by modified HKG banding technique in maize chromosomes

Abstract: A new heterochromatin banding pattern revealed by modified HKG banding technique in maize chromosomes

An Air Drying Technique for Maize Chromosomes without Enzymatic Maceration

Abstract: The air drying technique, widely used in animal cytogenetics, was adapted for use with Zea mays L. chromosomes. Using a simple protocol without enzymatic maceration and avoiding the inconvenience of the squashing technique, good staining and C-banding were obtained from maize chromosome preparations.

Antagonistic effect of predacious Arthrobotrys fungi on infective Haemonchus placei larvae.

Abstract: Laboratory experiments were performed to investigate the ability of isolates from the predacious fungus species Arthrobotrys conoides (one isolate) and Al. robusta (four isolates) to trap and kill infective Haemonchus placei larvae. Three groups for each isolate were formed: group 1, fungi and infective larvae; group 2, fungi; group 3, infective larvae. There were statistically significant differences (P < 0.05) between the antagonistic effects of three isolates of A. robusta, but there was no such difference between the isolate of A. conoides and isolates of A. robusta. This result indicates that there can be a variation in the predatory capacity of different isolates within a single fungus species. After 20 days of assay, there was greater recuperation of infective H. placei larvae in group 3 compared to group 1.

Variation with caste of the mandibular gland secretion in the leaf-cutting antAtta sexdens rubropilosa

Abstract: InAtta sexdens rubropilosa, a strongly polyethic and polymorphic species of myrmicine ant, the contents of the mandibular gland vary with caste. Small workers of head width 0.5–1.8 mm, those generally engaged in duties inside the nest, contain chiefly 4-methyl-3-heptanone. Larger workers, those chiefly engaged in foraging, and the soldier caste contain a mixture dominated by neral and geranial, with very little of the ketone of the smaller workers. The soldiers have massive glands containing milligram amounts of neral and geranial. Virgin and mated females contain essentially only 4-methyl-3-heptanone, the amount increasing after mating, while virgin males have 4-methyl-3-heptanone and 4-methyl-3-heptanol in approximately equal proportions. Mated males have less secretion and lose the 4-methyl-3-heptanol.

Coleopteros associados a eucaliptocultura nas regioes de sao mateus e aracruz , espirito santo

Abstract: Colepteros foram coletados em plantios de eucalipto nas regioes de Sao Mateus e Aracruz (ES), de novembro de 1989 a outubro de 1990. Para a coleta dos insetos fo- ram utilizadas uma armadilha luminosa Intral modelo AL 012 e uma armadilha etan611- ca por regiao. Os insetos, coletados a calla 15 Bias, foram enviados ao Laboraterio de Entomologia Florestal da Universidade Federal de Vicosa, onde foram catalogados. Nos duas regioes foi coletado urn total de 146 especies de coleopteros, distribuidas em 23 famffias. Na regifio de Sao Mateus foram encontradas 113 especies de coleepteros e em Aracna 88, corn maior numero de individuos coletados, em armadilha luminosa, nests old= regiao. Dense total, 29 especies foram identificadas. Em armadilha luminoe sa coletou- se grande ntimero de individuos dos farnffias Carabidae, Dytiscidae, Elateri- dae, Hydrophilidae, Lagriidae, Lampyridae, Staphylinidae e Tenebrionidae, enquanto na armadilha etanolica predominaram exemplares de Nitidulidae, Passalidae e Scolytidae.

Production of pectin lyase by Penicillium griseoroseum as a function of the inoculum and culture conditions.

Abstract: Optimum activity of an extracellular pectin lyase produced by Penicillium griseoroseum in submerged culture was after 120 h using 0.1% (w/v) citrus pectin as substrate. Sucrose at 0.1% (w/v) stimulated enzyme production and citrus pectin gave the highest activity of enzyme per unit growth.

Partial characterization ofAspergillus fumigatus polygalacturonases for the degumming of natural fibers

Abstract: Aspergillus fumigatus strain 4, cultured on citrus pectin as the sole carbon source, produced polygalacturonases whose activity was optimum at 65°C and pH 3.5–4.5. The enzymes presented a bimodal thermostability for 10 min, but not 60 min, of incubation. Polygalacturonases showed pH stability between 3.0 to 9.0. The enzymes were stable when stored at 4–6°C for 90 days, but their activity was reduced by 24% when they were stored at 26–30°C. Orange pulp was the best pectic carbon source tested for the production of pectinases capable of retting ramie fibers. The reutilization of these enzymes was possible, suggesting the viability of industrial use of pectinases for degumming ramie fibers.

Determinação de sexo em abelhas: XXX. Influência da quantidade de alimento e do hormônio juvenil na determinação das castas em Partamona cupira helleri (Hymenoptera, Apidae, Meliponinae)

Abstract: In Partamona cupira, caste determination follows the general patterns of Trigonini bees. The effects of the juvenile hormone and the amount of food on the process were studied. The frequency of queens increased with the quantity of food ingest by the larvae and or whith the amount of juvenile hormone topically applicated. Queens emerged earlier than workers. Intercastes were not found, sugesting that castes differentiation is a canalised process in this species.

INTOXICAÇÃO CRÔNICA POR Pteridium aquilinum (L) Kuhn (Polypodiaceae) EM BOVINOS

Abstract: Sao descritos casos de neoplasias de bexiga e trato digestivo superior, seguindo a ingestao de samambaia (Pteridium aquilinum) em bovinos, diagnosticados pelo Centro de Diagnostico Veterinario da Universidade Federal de Santa Maria, Rio Grande do Sul, durante o periodo de 1964-1991. Hemangiomas foram os tumores mais comumente encontrados na bexiga, levando ao aparecimento de hematuria. Carcinomas epidermoides foram encontrados no sistema digestivo superior causando sinais clinicos que variaram com o local da lesao, constatando-se dificuldade de degluticao, emagrecimento, dificuldade respiratoria, tosse e timpanismo. Alguns animais apresentaram concomitantemente tumores nas duas localizacoes. Tambem ocorreram papilomas associados a tumores de bexiga e trato digestivo superior em algumas ocasioes.

Pollination biology of Ternstroemia laevigata and T. dentata (Theaceae).

Abstract: The flowers of two species ofTernstroemia from Central Amazonia were observed to be pollinated by female bees performing vibrational foraging. The anthers of these flowers are longitudinally dehiscent. They are completely included in a petal tube, which opens by a small pore at the apex. Pollen is expelled out of this pore when the bees vibrate the flower while curling over the apex of the petal tube. The much elongated connectives probably transmit the vibrations from the petals to the anthers. The possible occurrence of this mode of pollination in other species ofTernstroemia is briefly discussed.

Trophallaxis in a primitively social sphecid wasp

Abstract: In a total of six hours of observation of severalMicrostigmus nigrophthalmus nests with two or more adult wasps, nine buccal contacts, six between females and three between females and males were observed. Except for two cases, these occurred soon after one of the females involved (the apparent donor) had returned to the nest and involved transfer from older to younger individuals. Experimental feeding of colored solution confirmed the occurrence of trophallaxis. InM. nigrophthalmus, trophallaxis seems to have arisen as a prolongation of maternal care since food is transferred from an older to a younger individual.

The influence of the soil phosphate capacity factor on soil and plant phosphorus critical levels of different vegetables

Abstract: A glasshouse experiment was carried out to study the effect of soil characteristics on soil and plant critical levels of P for the growth of tomato (Lycopersicum esculentum) and peruvian carrot (Arracacia xanthorrhiza), in a first cultivation, and cucumber (Cucumis sativus) or lettuce (Lactuca sativa) in a second cultivation. Samples of six soils received six rates of soluble P (0, 100, 200, 450, 700, and 1000 mg of P dm−3 of soil). Soil available P was determined by Mehlich-1 and Bray-1 extractants. Plant tops were harvested, oven dried, and total-P was determined. For lettuce, leaf tissue inorganic P (Pi), organic P and total acid soluble P (Pts) were determined. Soil and plant P critical levels varied for species and soils, and both varied inversely with the phosphate capacity factor (PCF). Critical concentrations of Pts and Pi; varied inversely with soil characteristics associated with soil P adsorption and accounted for the correlation verified between plant critical level and PCF.

Adaptabilidade e estabilidade de comportamento de cultivares de feijão em quatro municipios da zona da mata de minas gerais

Abstract: Estudou-se o comportamento dos seguintes cultivares e linhagens de feijdo Wham seolus vulgaris `Ouzo Negro 1992', 'RAB -94', 'CNF 5547', 'Owe, 'Manteigio Fosco 11', 'Carioca', Linhagem 2177, WAF-T, 'Negrito 897', ‘Milionario 1732', Linhagem 2172 e 'Rico 1735'. Para canto, foram conduzidos 20 ensaios na Zona da Math de Minas Gerais, sendo oito em Vicosa, quatro em Coimbra, quatro em Ponte Nova e quatro em Leopoldina. Foram instalados taste no plantio das "Aguas" (dois ensaios) quanto no da "seca" (quatro ensaios) e do invemo (14 ensaios). Dois niveis de adubacsio foram utilizados, sem nenhum exame previo do solo, com a fmalidade de criar ambientes maks, ou memos, favoraveis a cultura. Foil irealizado o controle de doencas, pois elan, com as suss ragas fisiologicas de distribuicao geogratica desconhecida, nap foram consideradas como verdadeiros componentes do ambiente. Com os dados de producio foram estudadas a adaptabilidade e a estabilidade de comportamento desses cultivares e linhagens pelo metodo de EB ERHART e RUSSEL (7). Concluiu se o se- guinte: 1) Os cvs. mais produtivos sio o ‘RAB 94', o 'Ouro Negro 1992', o 'CNF 5547' e o Duro'. Todos respondem bem a melhoria ambiental, mas apresentam instabilidade de comportamento. 2) Os memos produtivos sio o 'Carioca', a Linhagem 2177, o ‘WAF-7' e o 'Man- teigio Fosco 11', que respondem pouco a melhoria do ambiente; mas, com exceesao dos dois tiltimos, apresentam estabilidade de comportamento. 3) Os demais ficaram mama posigio intermediaria quanto a produtividade e reagab a melhoria smbiental, e somente o 1732' exibiu estabilidade de comportamento.

Duração do período ninfal e sobrevivência do predador Podisus connexivus Bergroth (Hemiptera, Pentatomidae), em três presas alternativas

Abstract: Longevity and survival of the predator Podisus connexivus (Hemiptera: Pentatomidae) were studied in three alternative preys: T1 - Bombyx mori (Lepidoptera, Bombycidae) catterpilars; T2 - Musca domestica (Diptera, Muscidae) larva and T3 - Tenebrio molitor (Coleoptera, Tenebrionidae) larva. Longevity and survival were: 22,1±0,6 days and 54,3±5,3%; 25,2±1,3 days and 56,0±4,9% and 22,0±0,8 days and 34,6±8,6%, for treatments T1, T2 and T3, respectively. Comparing to other researches, a lower survival was found. This is probably because a F2 generation from field material, was used. Since the insect was not well adapted to the laboratory conditions this could have led to lower survival.

Estudo comparativo da qualidade microbiológica de hambúrgueres processados artesanal e industrialmente

Abstract: Avaliou-se a qualidade microbiologica de hambargruer processado industrial e zuviss tesanalmente, corn o objetivo de se verificarem as condicees higiOnicas do produto cm e do produto pronto para e consumo. As amostras foram adquiridas mensalmente de doffs pontos varejistas de comercializacao e avaliadas quanto a populagio de bactenas mesofilas aerobias, Ntimero Mais Provavel (NMP) de coliformes totais e coliformes fecais, presenca de E. con, E. coli enteropatogenica e Salmonella. produto processado industrialmente deve ser considerado corm improprio para consumo humano, em virtude da presenca de Salmonella em algumas das amostras analisadas. produto processado artesanalmente, quango cru, revelou major carga microbiana quanto ao ntimero de microrganismos mesafilos aerobios, coliformes totais e coke formes fecais (fora do padrio), contudo nab veiculou Salmonella. C3 produto pronto parka consumo processado de modo artesanal parece ter sides convenientemente preparado, uma vez que apresentou acentuada reducao de carga microbiana inicialmente presente.