The oriental fruit moth, Grapholita molesta (Busck), is the most serious pest in peach, and several insecticide applications are required to reduce crop damage to acceptable levels. Geostatistics and Geographic Information Systems (GIS) are employed to measure the range of spatial correlation of G. molesta in order to define the optimum sampling distance for performing spatial analysis and to determine the current distribution of the pest in peach orchards of southern Uruguay. From 2007 to 2010, 135 pheromone traps per season were installed and georeferenced in peach orchards distributed over 50,000 ha. Male adult captures were recorded weekly from September to April. Structural analysis of the captures was performed, yielding 14 semivariograms for the accumulated captures analyzed by generation and growing season. Two sets of maps were constructed to describe the pest distribution. Nine significant models were obtained in the 14 evaluated periods. The range estimated for the correlation was from 908 to 6884 m. Three hot spots of high population level and some areas with comparatively low populations were constant over the 3-year period, while there is a greater variation in the size of the population in different generations and years in other areas.

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Grapevine phylloxera, Daktulosphaira vitifoliae (Fitch) (Hemiptera: Phylloxeridae) is a worldwide pest of Vitis species. It has forms that feed on leaves and roots. Root forms predominate on Vitis vinifera (L.) cultivars, while leaf forms predominate on Vitis species from its native American range. Recently, high densities of D. vitifoliae infestations in leaves of V. vinifera in Brazil, Peru, and Uruguay have been reported. The aims of this study were to determine the seasonal development of grape phylloxera, quantify infestation levels on V. vinifera leaves, and compare them with infestation levels on leaves of a rootstock of American origin. Studies were conducted in two vineyards in Uruguay from 2004–2007. Terminal shoots of 3309 C and Cabernet Sauvignon, Chardonnay, Tannat, Viognier, grafted onto resistant rootstock, were sampled weekly and leaves examined for gall presence and insect life stage. First galls were detected in early October; eggs began to appear within two weeks. Two oviposition peaks occurred by the end of December, and they coincided with bursts of shoot growth. On 3309C rootstock, oviposition peaks were more frequent than on the European cultivars. Based on thermal accumulation, D. vitifoliae could complete eight generations a year in Uruguay. Rootstock 3309C suffered the greatest damage but in some cases was similar to the European cultivars. Damage to Chardonnay, Cabernet Sauvignon and Viognier were also high. There were no galls on Tannat. The 2005–2006 season was characterized by low infestation rates caused by a prolonged drought that affected vegetative growth. There were also differences between vineyards, where the vigorous plants suffering more damage. Leaf galling phylloxera incidence and damage were mainly associated to the cultivar but plant vigor and environmental factors also contributed to increase the incidence.

RESUMONo presente trabalho objetivou-se avaliar o comportamento de cultivares de alface conduzidas sob sistema de cultivo orgânico nas condições edafoclimáticas de Seropédica-RJ. Foram conduzidos dois experimentos independentes, em campo, em duas épocas do ano, no delineamento em blocos casualizados, com três repetições e doze plantas por parcela. No primeiro e segundo experimentos foram utilizados como tratamentos 22 e 25 cultivares de alface, respectivamente, pertencentes aos grupos crespa, lisa e americana. Nas avaliações dos dois experimentos foram considerados os caracteres massa fresca da parte aérea, diâmetro de cabeça, número de folhas, massa fresca de folhas e comprimento de caule. Ao considerar os cinco caracteres avaliados, para cada grupo de alface, infere-se que para as condições edafoclimáticas de Seropédica-RJ e manejo utilizando o biofertilizante Agrobio ® as cultivares Hortência, Regina de Verão, Stella, Tainá e Raider Plus apresentaram melhor desempenho. Palavras-chave: biofertilizante, Lactuca sativa, pendoamento precoce, produçãoLettuce cultivars in organic farm system on winter and spring from Baixada Fluminense, State Rio de Janeiro, Brazil ABSTRACT At this present research, the aim was to assess the lettuce cultivars behavior above the organic farm system in climate and soil conditions at Seropédica-RJ. It was conducted two independent experiments, in the field, in two periods of the year, on randomized block design, with three repetitions and twelve plants per plot. In the first and second experiments were utilized as treatments 22 and 25 lettuce cultivars, respectively, belonging to the looseleaf and iceberg lettuce groups. In assessments of those experiments were considered fresh mass characters of the área part, head diameter, number of leaves, fresh mass of leaves and length of stem. When considering those five characters, for each group of lettuce, deduced that for the climate and soil conditions of Seropédica-RJ and management using the biofertilizer Agrobio ® the cultivars Hortência, Regina de Verão, Stella, Tainá and Raider Plus had better performance.