Daiane Luckmann

Influência do uso de AIB, época de coleta e tamanho de estaca na propagação vegetativa de hibisco por estaquia

Effects of IBA concentration, collection time and cutting length on hibiscus cutting propagation Vegetative propagation by tip cutting can be influenced by factors such as collection time, cutting length, auxin concentration and cutting physiological status. The ornamental Hibiscus ( Hibiscus sp.) is commercially propagated by cuttings. Therefore, there is a need to study the influence of these factors on the rooting capacity of this specie. The aim of this work was to evaluate the IBA effect, cutting length and collection time on Hibiscus tip cutting propagation. The experiment was carried out in the plant production sector of the Universidade Tecnologica Federal do Parana, Campus Dois Vizinhos, Dois Vizinhos, PR (Brazil). The experiment was arranged in a 3 x 2 x 2 factorial completely randomized block, (IBA concentration x cutting length x collection time), with four replications, with each plot consisting of ten cuts. Two collecttion times (June and September), two shoot cutting lengths (6 and 12 cm) and three IBA concentrations (0; 1 and 2 g L -1 ) were tested. At the two collection times, after 77 days, the rooting percentage, number

Indução de fitoalexinas em cotilédones de soja em resposta a derivados de folhas de pitangueira

The worldwide demand for food without pesticides has stimulated the research on alternative methods to control pathogens in plants. The activation of defense mechanisms by inductors seems a viable and promising alternative. The use of medicinal plants extracts has demonstrated capacity to induce the production of phytoalexins, as a mechanism of defense in treated plants. The objective of this research was to verify the potential of Eugenia uniflora L. (surinan cherry) to induce phytoalexins in cotyledons of soybean (Glycine max). The derivatives alcoholic extract, infusion, maceration and decoction, obtained of surinan cherry were used in the concentrations of 0.1; 1; 10 and 40%, beyond essential oil. Water was used for the control and chitosan (1%) as inductor reference. The preparations of surinan cherry presented capacity of induction of the phytoalexins glyceolin in cotyledons of soybean, with the increasing concentration of the preparations. The essential oil presents detachable effect in the induction of phytoalexins in relation to the other preparations. Chitosan induces phytoalexins in cotyledons soybean and can be used in similar studies as a reference inductor.

Produtos Alternativos para Controle de Thaumastocoris peregrinus e Indução de Resistência em Plantas

This study aimed to evaluate the effect of alternative insecticide on Thaumastocoris peregrinus, as well as the potential to act in the resistance induction process in plants. Leaves of Eucalyptus camaldulensis were immersed in the solution of Orobor®, Topneem®, Rotenat®, Rotenat CE®, Baicao®, Compostonat®, Pironat®, Assist®, garlic extract and bordeaux mixture. They were subsequently transferred to tubes containing 10 adults of T. peregrinus, assessing daily the number of dead insects. The products with insecticidal effect were tested for their potential to induce resistance, evaluating the synthesis of the phytoalexin glyceollin (pterocarpanoide) and phenylpropanoids route activation in soybean cotyledons by the enzyme phenylalanine ammonia-lyase. We used water as control and chitosan (1%) as an inductor of reference. Rotenat®, Compostonat®, Rotenat CE® and Topneem® showed insecticidal effect while Rotenat CE® and Topneem® showed potential as resistance inducers, expressing significant amounts of phytoalexins and activity of PAL (phenylalanine ammonia-lyase).

Seletividade de produtos naturais comerciais a Trichogramma pretiosum (Riley, 1879) (Hymenoptera: Trichogrammatidae)

The selectivity of natural products to parasitoids is not well known. Thus, the objective of this work was to evaluate the selectivity of this commercial natural products to Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae). The products used in the experiment were the following: Baicao®, Orobor® and Topneem® at doses recommended by the manufacturers and were sprayed on cards containing sterilized eggs of Anagasta kuehniella Zeller (Lepidoptera: Pyralidae). For the free-choice test, a T. pretiosumfemale was confined with two cards, one of them was sprayed with the natural products and the other was considered control, evaluating the percentage of parasitism. The no-choice test consisted in spraying treatments on cards previously or subsequently to parasitism. The number of parasitized eggs, percentage of emergence and longevity of adults were evaluated in both tests. Topneem® and Baicao® showed increase in parasitism of T. pretiosum in the free-choice test. Baicao® sprayed previously on cards containing eggs of A. kuehniellahad a negative effect on the emergency of T. pretiosum in the no-choice test. A reduction in the number of parasitizedeggs was found when Baicao® was sprayed previously in the parasitism treatment. Orobor® was selective to T. pretiosum in the experiment conditions and it did not affect negatively the parameters evaluated. Baicao® was not selective to T. pretiosum, it affected negatively most of the parameters evaluated, and classified as slightly harmful for toxicity to T. pretiosum adults under laboratory conditions.