Lino Bittencourt Monteiro

Manejo integrado de pragas em macieira no Rio Grande do Sul II: uso de Neoseiulus californicus para o controle de Panonychus ulmi

Having the purpose to increment the biological control of European red mites Panonychus ulmi in apple tree, a control strategy was proposed based on phytoseids Neoseiulus californicus in a greenhouse, on successive inoculative releases and use of acaricides, in a commercial apple orchard of Rincao das Flores Agropastoril (Agriflor), in Vacaria, Rio Grande do Sul, Brazil, among 1992-1996. The red mite samples guided both phytoseid releasing and transfering from the greenhouse and unwanted branches pruned, to apples trees with high population rates of European red mites. The inseticide effects on phytoseids were used to choose the pesticides for pest control. During the first winter season, the association between acaricides and phytoseids was able to reduce overwinter eggs, about 1,3 eggs/bud unit, while in the control area had 59,8 eggs. In the second year, the reduction of European red mite populations was significant. After the following two years, the control of European red mites was done only using the phytoseids. In the years that followed its introduction, N. californicus resurged on the apple trees.

Capacidade de parasitismo de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) em ovos de Bonagota salubricola (Meyrick) (Lepidoptera: Tortricidae) sob diferentes temperaturas

The parasitism capacity of Trichogramma pretiosum Riley strain bonagota on Bonagota salubricola (Meyrick) eggs was studied under the temperatures of 18, 20, 22, 25, 28, 30 and 32 degrees C. The number of days with parasitism, accumulated parasitism, total number of eggs parasitized per female and parasitoid longevity was evaluated. In the first 24h, parasitism ranged from 1.6 (32 degrees C) to 8.8 (22 degrees C) eggs of B. salubricola. Accumulated egg parasitism of B. salubricola reached 80% in 1st to 4th day at 20 degrees C to 32 degrees C, respectively, and in the 7th day at 18 degrees C. Temperatures from 18 degrees C to 22 degrees C were the best suited for the total eggs parasitized for female, resulting in 35.4 and 24.6 eggs/male respectively. T. pretiosum female longevity ranged from 7.8 to 2.5 days, at 18 degrees C and 32 degrees C, respectively. The results showed that T. pretiosum strain bonagota is better adapted to temperatures from 18 degrees C to 22 degrees C.

SELETIVIDADE DE INSETICIDAS A Neoseiulus californicus MCGREGOR (ACARI: PHYTOSEIIDAE) EM MACIEIRA, NO RIO GRANDE DO SUL

The side-effects of agrochemical to Neoseiulus californicus (Acari: Phytoseiidae) were studied in laboratory. The mites were collected in commercial apple orchard of Agropastoril Rincao das Flores, in Vacaria, Rio Grande do Sul, Brazil, after successive inoculative releases. The insecticids used were recommended to control of same pest, as Anastrepha fraterculus (Diptera: Tephritidae). The reproduction effect and mortality were evalued 12, 24, 48 and 96 hours after pulverization, while the agrochemical were ranked in toxicity classes, according to IOBC/WPRS. Azinphos ethyl, deltametrina e fenthion were harmful with ca. 100% of mortality in 24 hours, dimethoate, fenitrotion, paration, phosmet e triclorfon were slightly harmful (class 2). Malation was harmless.

Infecção de Monilinia fructicola no período da floração e incidência de podridão parda em frutos de pessegueiro em dois sistemas de produção

A podridao parda (Monilinia fructicola) do pessegueiro foi avaliada objetivando comparar os sistemas de producao integrada (PI) e convencional (PC), em experimentos conduzidos nos municipios de Araucaria e Lapa, ambos no Parana, nas safras 2002/03 e 2003/04. Para tanto foi avaliada a infeccao de M. fructicola em cinco fases da floracao e a incidencia da podridao parda em frutos na colheita, verificando correlacao entre infeccao de M. fructicola na floracao com a incidencia da doenca em frutos na colheita. Durante o florescimento, a incidencia do patogeno foi avaliada nas fases de gema inchada, botao rosado, botao aberto, plena floracao, queda de petalas. Na maturacao dos frutos, avaliou-se a incidencia de podridao parda considerando toda a producao no decorrer da colheita. Os dados de incidencia da doenca nas fases da floracao foram agrupados em tres covariaveis: total de estruturas doentes durante toda a floracao (CV1), na plena (CV2) e na queda de petala (CV3), analisadas em relacao aos sistemas e correlacionando com a incidencia na colheita. A presenca do patogeno foi constatada somente nas estruturas florais, estames e estigma, a partir da flor totalmente aberta. A PI proporcionou menor incidencia de doenca durante a floracao em 2002/03 em Araucaria e nos dois anos, na Lapa. Na colheita houve 5% a mais de doenca na PI em Araucaria na safra 2002/03, no entanto na safra seguinte a doenca apresentou a mesma intensidade nos dois sistemas. Na Lapa a PI foi mais eficiente no controle da doenca. Houve correlacao significativa para as covariaveis CV1 e CV3 na safra 2002/03.

Avaliação de atrativos alimentares utilizados no monitoramento de mosca-das-frutas em pessegueiro na lapa- PR

Fruit flies of Anastrepha genus are a key pest in peach trees in Parana. Food attractants were tested to determine their efficiency in monitoring fruit flies captured in McPhail fly traps. The experiment was conducted over a period of three years. In 2002 the following attractors were tested: Maguari® brand grape juice, BioAnastrepha® brand hydrolyzed enzymatic protein and Chemin Agrin® vinegar. Over the next two years, the vinegar was replaced by Torula® hydrolyzed protein compound. Protein-based attractants were the most efficient in trapping Anastrepha spp. and captured flies earlier comparing to grape juice. According to the results, the use of protein-based attractants for monitoring Anastrepha spp in the Lapa peach trees was recommended.

Produção, teor foliar e qualidade de frutos do pessegueiro 'Chimarrita' em função da adubação nitrogenada, na região da Lapa-PR

The peach (Prunus persica L. Batsch) integrated production regulates the N rates to be applied in order to obtain high yield and fruit quality without affecting plant sanity and environmental quality. However, there is a great lack of local information about N rate that it is necessary to achieve high yield for orchard at Lapa origin. So, an experiment was implanted in 5-year old commercial orchard, in the Lapa County, Parana State, Brazil where it was evaluated N rates effect over the fruit yield, leaves concentration and quality, during three years. The experimental design was a randomized block with three treatments and three replications. The treatments were three N rates (40, 80 and 160 kg of N ha-1 ano-1), using urea as N source. The reduction in nitrogen fertilization, in established orchard, diminished the yield only for the second year. There was an accumulated yield decrease of 8,4 t ha-1 during three years, comparing the smallest to largest rate. The yield was straight associated with fruit number since the fruit mass and caliber were not affected by N application. The N fertilization did not effect fruit qualitative proprieties evaluated (total soluble solids, acidity total titratable and firmness of the pulp) and them values stayed within range concentration considered normal for cultivar. Leave tissue analysis showed that only N concentration was affected by the N fertilization for the three evaluated years, but being in normal levels for all treatments. The Ca, Mg, Fe and Zn leaves concentration was below normal level established for peach..

Comparação econômica entre controle biológico e químico para o manejo de ácaro-vermelho em macieira

Red spider mite, Panonychus ulmi (Acari: Tetranychidae) is a significant pest in apple tree in Fraiburgo, Santa Catarina (SC) and applied biological control was implemented in the mid-nineties. The objective of this study was to demonstrate the economic benefits of biological control in the management of red spider mite. The assessment was carried out in two commercial orchards, one of which was subjected to biological control of spider mite by releasing the predator Neoseiulus californicus, insecticide selection and weed management, and the other to conventional arthropod management, based on the application of chemicals to control insects, phytofagous mites and weed. Economic analysis showed that the costs for labor and machines were similar in both orchards; however acaricide costs were significantly lower in the orchard subjected to biological control, demonstrating that despite the need for investment in predator mite breeding apparatus and maintenance costs, the biological strategy was economically viable.

Biology of the Two-Spotted Spider Mite on Strawberry Plants

The two-spotted spider mite, Tetranychus urticae Koch, is commonly found on strawberry crops (Fragaria x ananassa). Strawberry plants have defensive mechanisms, which in turn influence the behavior of herbivores. The oviposition and development of the two-spotted spider mite were evaluated on the leaf disks of the cultivars ‘Aromas,’ ‘Camarosa,’ ‘Camino Real,’ ‘Diamante,’ ‘Diamante 10,’ ‘Diamante 50,’ ‘Festival,’ and ‘Seascape.’ It was observed that on cultivars such as ‘Aromas,’ ‘Camarosa,’ and ‘Seascape,’ immature survivorship was higher, but no difference was found during the developmental period from egg to adult of T. urticae. The immature development time was also longer on ‘Camarosa.’ Females laid more eggs on ‘Seascape’ (8.4 eggs/day), and the least on ‘Camarosa’ (1.0 egg/day). Mortality was higher at the larval stage and reached more than 50% in three cultivars ‘Camarosa,’ ‘Diamante,’ and ‘Seascape.’ Thus, the cultivars ‘Camarosa,’ ‘Diamante,’ and ‘Seascape’ were the ones that mostly affected the survival, development, and reproduction of T. urticae.

Oviposition behavior of Grapholita molesta Busck (Lepidoptera: Tortricidae) at different temperatures

Cultivation of temperate-climate fruits is economically important for Brazil. Grapholita molesta Busck is a pest that causes damage to apples, peaches, plums, and pears growing in different micro-regions of southern Brazil, and understanding its reproductive behavior is essential to develop control strategies. The objective of this study was to ascertain the influence of different temperatures (13, 16, 19, 22, and 25ºC) on the oviposition behavior of G. molesta. Females of G. molesta were placed in individual plastic containers, and the pre-oviposition period and the number of eggs laid were assessed until adult death. Temperature influenced the pre-oviposition period, and females kept at 22º were the first to lay their eggs. Oviposition occurred over a longer period of time at 13ºC than at the higher temperatures. The highest total number of eggs was obtained at 19ºC, with the mean daily oviposition being directly proportional to the temperature. There was a negative interaction between the pre-oviposition period and the total number of eggs laid by females. The most suitable temperature for oviposition of G. molesta was 19ºC.

Efeito do manejo de plantas daninhas sobre Neoseiulus californicus (Acari:Phytoseiidae) em pomar de macieira

The influence of weed management on tetranychid mites (Panonychus ulmi and Tetranychus urticae) and phytoseids movement was evaluated. Neoseiulus californicus populations were released in an apple orchard for biological control of tetranychid mites. Three kinds of weed management were used: no weed control at all, manual control and control with herbicide. The mites were evaluated in Plantago tormentosa, Erigeron sp, and apple tree leaves. The highest population of N. californicus was observed where weed was not controlled. Tetranychid mites populations were abundant on apple trees when herbicide was used, probably due to the low population of N. californicus. P. tormentosa was the preferred host of phytoseids. The conclusion was that weed management plays an important role in the regulation of mite species in apple orchards.