Nota corta. Especies de ácaros fitoseidos (Acari: Phytoseiidae) en manzanos de Río Negro, Argentina

The presence of phytoseiid mites was determined in two unsprayed apple orchards at Cinco Saltos and Cipolletti, Río Negro Province, Argentina. Twenty apple trees were chosen in each orchard and a sample of 10 leaves per tree was taken at seven different sampling dates. Neoseiulus californicus (McGregor), Euseius fructicolus (Gonzalez &Schuster) and Paraseiulus talbii Athias-Henriot were found at Cinco Saltos, and Proprioseiopsis messor (Wainstein), N. californicus and Metaseiulus camelliae (Chant & Yoshida-Shaul) at Cipolletti. Of these species, only N. californicus has previously been reported from the Alto Valle del Río Negro region. Proprioseiopsis messor and Paraseiulus talbii are reported for the first time in South America and on the American Continent respectively.Se llevó a cabo un estudio para determinar la presencia de ácaros fitoseidos en dos plantaciones de manzanos no tratadas con plaguicidas, localizadas en Cinco Saltos y Cipolletti, Provincia de Río Negro, Argentina. Se seleccionaron 20 árboles en cada huerto y se tomó una muestra de 10 hojas por árbol en siete diferentes fechas de muestreo. Neoseiulus. californicus (McGregor), Euseius fructicolus (Gonzalez & Schuster) y Paraseiulus talbii Athias-Henriot fueron las especies identificadas en Cinco Saltos. Proprioseiopsis messor (Wainstein), N. californicus y Metaseiulus camelliae (Chant & Yoshida-Shaul) fueron identificadas en Cipolletti. De las especies recolectadas solamente había sido mencionada previamente N. californicus en la región del Alto Valle del Río Negro. P. messor y P. talbii constituyen nuevas citas para América del Sur y el continente americano, respectivamente

Size of predatory mites and refuge entrance determine success of biological control of the coconut mite

Published online: 06 July 2016Predators face the challenge of accessing prey that live in sheltered habitats. The coconut mite Aceriaguerreronis Keifer (Acari: Eriophyidae) lives hidden beneath the perianth, which is appressed to the coconut fruit surface, where they feed on the meristematic tissue. Its natural enemy, the predatory mite Neoseiuluspaspalivorus De Leon (Acari: Phytoseiidae), is larger than this pest and is believed to gain access to the refuge only after its opening has increased with coconut fruit age. In the field, experimentally enlarging the perianth-rim-fruit distance beyond the size of the predators resulted in earlier predator occurrence beneath the perianth and lower numbers of coconut mites. On non-manipulated coconut fruits, the predators gained access to the prey weeks later than on manipulated ones, resulting in higher pest densities of coconut mites. Successful biological control thus critically hinges on the size of the predator relative to the opening of the prey refuge

Controle biológico do ácaro rajado com ácaros predadores fitoseídeos (Acari: Tetranychidae, Phytoseiidae) em culturas de pepino e morango

O ácaro rajado, Tetranychus urticae Koch, é considerado uma das principais pragas de hortaliças e várias outras culturas no Brasil, em áreas onde um considerável volume de acaricidas é anualmente empregado no seu controle. O objetivo deste trabalho foi testar a viabilidade técnica do emprego dos fitoseídeos Amblyseius idaeus (Denmark & Muma) e Phytoseudus macropilis (Banks), comum ente encontrados no Brasil, no controle de T. urticae em pepino e morangueiro em Jaguaríúna,SP. Utilizou-se o delineamento experimental em blocos casualizados, com 4 repetições e 4 tratamentos (T1-T4) para o pepino e 5 tratamentos para o morangueiro (T1-T5): T1, testemunha; T2, pulverizações semanais de Malation para a exclusão de predadores nativos; T3, liberações periódicas de A.idaeus; T4, liberações periódicas de P.macropilis; T5, pulverizações semanais de avermectina para a exclusão de ácaros fitófagos e predadores nativos. Apenas A.idaeus se estabeleceu na cultura de pepino, reduzindo significativamente a população de T. urticae. Ambas espécies de predadores se estabeleceram na cultura do morango e reduziram significativamente a população de T.urticae.The two-spotted spider mite, Tetranychus urticae Koch, is considered one of the main pests of horticultural and other crops in Brazil, in areas where a considerable volume of acaricides is annually used for its control. The objective of this work was to test the technical viability of using phytoseiids Amblyseius idaeus (Denmark & Muma) and Phytoseudus macropilis (Banks), commonly found in Brazil, to control T .urticae in cucumber and strawberry crops in Jaguaríúna,SP. A randomized complete block design was used, with 4 replicates and 4 treatments for cucumber (T1-T4) and 5 treatments for strawberry crops (T1-T5): T1, control; T2, weekly sprays of malathion for exclusion of native predators; T3, periodical releases of A.idaeus; T4, periodical releases of P. macropilis; T5, weekly sprays of avermectin for exclusion of native phytophagous and predatory mites. Only A. idaeus was successfully established on cucumber, significantly reducing T. urticae population. Both released phytoseiid species were established on strawberry and reduced significantly the population of T. urticae

Control of citrus scab, melanose and leprosis with fungicides and miticide mixed to foliar fertilizer

Pulverizações com ziram (Rodisan SC), oxicloreto de cobre (Coprantol BR) e óxido de fembutatina (Torque 500 SC) em dosagens normais e subdosagens, isoladamente ou em mistura com um adubo foliar originário da fermentação glutâmica do melaço, controlaram de forma efetiva a verrugose, melanose e leprose em laranja pera. A aplicação isolada do resíduo da fermentação glutâmica do melaço, base para diversos adubos foliares, nas dosagens de 0,25% e 5% do produto comercial Ajifol, não interferiu na ocorrência de verrugose e melanose. Entretanto, ocasionou um aumento do número de frutos com leprose, do número de lesões de leprose por fruto e do número de ácaros da leprose (Brevipalpus phoenicis Geipsks) nas folhas e nos frutos.Normal dosage and tinder-dosage sprays of ziram (Rodisan SC); cooper oxychloride (Coprantol BR) and fenbutatin oxide (Torque 500 SC), isolately or in association with Ajifol, a foliar fertilizer from molasses glutamic fermentation, provided efficient control of scab, melanose and leprosis in 'Pera' orange. Sprays of Ajifol at 0.25 and 5% had no effect on the rate of occurrence of scab and melanose, but was correlated with increases in the rates of fruits with symptoms of leprosis, number of leprosis spots per fruit, and the number of leprosis mites (Brevipalpus phoenicis Geijskes) on leaves and fruits

Native phytoseiid mites as indicators of non-target eVects of the introduction of Typhlodromalus aripo for the biological control of cassava green mite in Africa

Article purchasedThe need to evaluate non-target effects of classical biological control of arthropod pests has received considerable attention in recent years. We determined with repeated field surveys the changes in abundance and distribution of the phytoseiid mite fauna in cassava fields resulting from the introduction of the neotropical phytoseiid Typhlodromalus aripo into two countries—Malawi and Mozambique—in southern Africa for the biological control of Mononychellus tanajoa. Typhlodromalus aripo abundance was similar, while the abundance of the target pest M. tanajoa declined progressively, during the 2 years after the introduction of T. aripo into the target countries. We did not detect any changes in the abundance of the most common native phytoseiids mites—Euseius baetae, Euseius bwende and Ueckermannseius saltus—on cassava in Mozambique. In contrast, the abundance of two of the most common native phytoseiids, Euseius fustis and Iphiseius degenerans, on cassava in Malawi were apparently facilitated—i.e., their abundance was enhanced by the introduction of T. aripo; while the abundance of a third species, U. saltus, was not affected. For only one species, E. baetae, within-plant distribution shifted to the lower parts of the cassava canopy as a result of the introduction of T. aripo, which resides in the upper parts of the cassava canopy, but without any measurable negative effects on biological control of M. tanajoa. While the overall abundance of phytoseiid mites found on non-cassava vegetation was not affected by T. aripo introduction, there were some changes in relative abundance of some species in Malawi. Possible mechanism for the increase in abundance of I. degenerans and E. fustis in Malawi, and changes in within-plant distribution of E. baetae and I. degenerans in Mozambique and Malawi, respectively, are discussed. The methodology developed for assessing potential non-target effects of T. aripo introduction into southern Africa has significantly advanced classical biological control efforts against an economically important cassava pest