Regina da Silva Borba

Dissimilaridade genética de linhagens de Trichogramma Westwood (Hymenoptera: Trichogrammatidae) através de marcadores moleculares ISSR

Demands for sustainable agricultural systems have forested the development of biological control techniques, such as the use of the egg parasitoid Trichogramma Westwood. However, the arduous identification of the parasitoid at the species level, due to the tiny size and the morphological similarities is an obstacle to increasing its use. Molecular markers are useful to reach the specimen genome and avoid environmental effects that could misguide identification. Several molecular markers techniques are available and the ISSR technique has been used to differentiate close individuals, due to its high polymorphism level, reproducibility and low cost. The objective of this study was to measure the level of genetic differentiation among five lines of Trichogramma, using ISSR markers: three belonging to the species T. pretiosum Riley, one to T. atopovirilia Oatman & Platner and one to T. bruni Nagaraja. Morphological identification of the parasitoids was conducted at ESALQ/USP - Piracicaba, SP. After DNA removal and standatization, PCR reactions were performed with 26 ISSR primers; 11 of them were selected because they presented greater polymorphism and consistency. Molecular data were converted into a binary matrix and analyzed (NTSYS v. 2.1). The 11 primers produced 172 polymorphic sections. Genetic similarity ranged from 19% to 96%, showing that the ISSR technique can efficiently identify DNA polymorphism in Trichogramma. Results also indicate important inter and intra-specific variations among the parasitoid lines.

Crescimento do fungo simbionte de formigas cortadeiras do gênero Acromyrmex em meios de cultura com diferentes extratos

The cutter ants show preference for some vegetable species, which are constantly defoliated, while others are not attacked, although they are abundant and located close to the nest. The ants of the goods Atta and Acromyrmex cut plants and they transport pieces to the anthills. The vegetable material is used for the cultivation of the mushroom Leucoagaricus gongylophorus, mushroom from of which theyfeed. Several works using extracts of plants have been accomplished to evaluate the effect on the development of the mushroom symbiont. The objective of this work was to evaluate the influence of added culture means of different extracts on the growth of the L. gongylophorus mushroom. Where mushrooms of the species Acromyrmex ambiguus, Acromyrmex crassispinus, Acromyrmex heyeri and Acromyrmex lundi were inoculated in the means Nutritious Agar and BDA, both added of molasses and extracts of Lolium multiflorum Lam., Typha angustifolia L. and ant (Atta sexdens piriventris). The Pagnocca medium was used as pattern. The plates were maintained in cameras acclimatized to the temperature of 25 + 1°C and 24 hours of darkness, for a period of 49 days. The fungal growth was evaluated with base in the diameter of the colony, which was accomplished with weekly intervals, totalizing seven evaluations. Also the dry weight was evaluated from the mushroom to the 53 days. The results showed that the mushroom cultivated by different species of ants has differentiated growth in culture means with different extracts.

Biologia e exigências térmicas de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) sobre ovos de Bonagota cranaodes (Meyrick) (Lepidoptera: Tortricidae)

Este trabalho teve como objetivo estudar a biologia de Trichogramma em laboratorio, visando a sua utilizacao em programas de manejo integrado para o controle de Bonagota cranaodes na cultura da macieira. A biologia de Trichogramma bruni Nagaraja e de duas linhagens (L3 e L4) de Trichogramma pretiosum foi realizada sobre ovos de B. cranaodes. Alem disso, suas exigencias termicas e o numero anual de geracoes tambem foram determinados. A linhagem L3 apresentou maior parasitismo (52,3%), no entanto, a viabilidade foi semelhante entre as linhagens estudadas, com ciclo evolutivo de 8,7 dias, longevidade de femeas de 10,65 dias, temperatura base de 11,35°C e constante termica de 128,70GD. O numero de geracoes anuais dessa linhagem em laboratorio foi de 47,22 e de 13,59 geracoes para as condicoes da regiao de Vacaria - RS. O baixo parasitismo de T. bruni e da linhagem L4 de T. pretiosum pode estar ligado a camada de secrecao existente sobre as posturas da praga. Embora este parasitismo seja considerado baixo, a utilizacao destas linhagens nao pode ser descartada dentro do sistema de Producao Integrada da Maca, devendo novos estudos serem realizados em condicoes de campo.

Pareamento de fungos cultivados por diferentes espécies de formigas cortadeiras no Rio Grande do Sul

This research work had as objective to study the possible heterokaryosis occurrence through the fusion of mushrooms originating from nests of different species of cutter ants collected in different areas of the State of Rio Grande do Sul, using the AFLP technique. Ten fusion groups were accomplished, from which two did not perform a colony coalition. After the fusion occurred, disks of mycelium of the colonies intersection area and fusion external areas were collected, the extraction of DNA and standardization was performed. PCR reactions were tested using 21 AFLP primer combinations, from which three were selected because they presented larger polymorphism and consistence. The molecular data were transformed at binary head office and analyzed by the statistical program NTSYS v. 2.1. The three combinations of primers generated 245 polymorphic bands. The average similarity of the genotypes varied from 0.03 to 0.18 in all the fusions. The large genetic distance found among the organisms possibly happened due to three factors: the possible heterokaryosis occurrence among the mushrooms; the use of mushrooms originating from different species of ants and; from different areas. This work suggests that the heterokaryosis can represent an important role in the life cycle of this mushroom, since it multiplies by clonal propagation and due to the absence of fructification.

Polimorfismo do fungo simbionte de formigas cortadeiras submetido à luz ultravioleta

O presente trabalho teve por objetivo verificar o efeito de diferentes periodos de luz ultravioleta sobre a similaridade genetica do fungo simbionte de formigas cortadeiras pertencentes as especies Acromyrmex ambiguus, Acromyrmex crassispinus e Acromyrmex lundi, atraves da tecnica AFLP. Os fungos foram inoculados em meio de cultura Pagnocca e mantidos em câmaras climatizadas a temperatura de 25 + 1°C e escotofase de 24h, por um periodo de 15 dias. Posteriormente, foram expostos a luz ultravioleta por periodos de: 0, 5, 10, 15, 20, 25 e 30 minutos. Aos 45 dias apos o tratamento, foi realizada a extracao do DNA e padronizacao, realizando-se as reacoes de PCR por meio de 24 combinacoes de primers AFLP, das quais quatro foram selecionadas por apresentarem maior polimorfismo e consistencia. Os dados moleculares foram transformados em matriz binaria e analisados pelo programa estatistico NTSYS v. 2.1. As quatro combinacoes de primers utilizadas geraram 152 bandas polimorficas. As populacoes de fungos originarias de diferentes especies de Acromyrmex apresentaram uma similaridade genetica media de 37%, sendo que a inducao de mutacao atraves da luz ultravioleta permitiu obter isolados mais dissimilares.

Desenvolvimento de mudas de pessegueiros submetidas a doses de glifosato

Development of peach seedlings treated with doses of glyphosate The region of the Serra Gaúcha is considered the third pole producer of peaches, where most of the production of peaches is for the table. Among the pesticides applied on peach tree in the Serra Gaúcha, glyphosate is among the most used by farmers. However, there are many authors have checked the phytotoxic action of glyphosate in different cultures. Therefore, the objective of this work was to verify the influence of the application of glyphosate herbicide in the development of seedlings of peach cultivar Chimarrita grafted on rootstock Capdeboscq. Peach seedlings transplanted in plastic pots containing soil were conducted in the greenhouse of the Federal Institute of Education, Science and Technology, campus Bento Gonçalves (IFRSBG). In the treatments were used five different doses of glyphosate (Roundup Original®): 1-Witness (without application of herbicides); 20.5 liter of commercial product.ha-1; 31 litre of commercial product.ha-1; 42 liters of commercial product.ha-1 and; 54 liters of commercial product ha-1. The variables analyzed were the symptoms of visual phytotoxicity, stem diameter (mm), length of shoot and roots (cm), root fresh mass (g), dry mass of shoots and roots (g). The data obtained were subjected to regression analysis and averages Cientific Paper 1 Doutoranda em Agronomia Produção Vegetal-PPGA. Universidade Estadual do Centro Oeste-UNICENTRO Rua Simeão Camargo Varela de Sá, 03, Bairro Cascavel, Guarapuava PR, 85040-080. Email: carine.rusin@gmail.com 2 Acadêmico Agronomia. Universidade Estadual do Centro Oeste-UNICENTRO Rua Simeão Camargo Varela de Sá, 03, Bairro Cascavel, Guarapuava PR, 85040-080. Email: marcoshorst@hotmail.com.br 4 Dra. Prof. Agronomia. Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul, Campus Bento Gonçalves (IFRS-BG) Rua Gen. Osório, 348 Centro, Bento Gonçalves-RS 95700-000. Email: andressa.comiotto@bento.ifrs.edu.br, regina.borba@bento. ifrs.edu.br