Occurrence of Phelypera griseofasciata and its parasitism in munguba in Seropédica, Rio de Janeiro

ABSTRACT: Pachira aquatica (Malvaceae), known as munguba, is cultivated for afforestation of many Brazilian cities. In Seropédica campus of UFRRJ, it was observed the defoliation of one specimen of Pachira aquatica with presence of larvae, pre-pupae, and pupae of beetle of the subfamily Hyperinae, which were reared in laboratory until the emergence of the adults; these insects were identified as belonging to the species Phelypera griseofasciata Capiomont (Coleoptera: Curculionidae). These immature forms (n=86) were again collected in this same specimen and reared in laboratory to verify the occurrence of parasitism. It was obtained 128 adults of Jaliscoa nudipennis Bouček (Hymenoptera: Pteromalidae), responsible for 44.2% of total parasitism. The sex ratio was 0.70, so the highest number of offspring was of females. Intersexual and intrasexual dimorphisms were also observed in J. nudipennis regarding the shape of the head and characteristics of the wings. This study is the first record of both insect species associated with Pachira aquatica in the state of Rio de Janeiro, Brazil.

Acute toxity and sublethal effects of pymetrozine on the whitefly parasitoid Encarsia formosa Gahan

Sublethal effects of a pymetrozine-based product (commercial product Chess 50 WP) on life history traits and population growth of one commercialized strain (?Dutch? strain) and two local populations (Bujanovac and Negotin) of the whitefly parasitoid Encarsia formosa Gahan (Hymenoptera: Aphelinidae) were evaluated in laboratory bioassays. All trials were carried out at 27?1?C temperature and under 60?10 % relative humidity and 16/8 h daylight/darkness photoperiod in four replications. Longevity of wasps exposed for 48 h to residues of the pymetrozine insecticide (LC50, 280 mg a.i./l) was shorter (by 2.7-3 days) than that of control wasps. Total parasitism of Negotin wasps was significantly reduced (by 8.2 %), as well as total parasitism and adult emergence of the Dutch strain (by 7.3 and 8.2 %, respectively), compared to control wasps. The instantaneous rate of increase (ri) of surviving adult wasps was also significantly reduced (by 6.6, 6.3 and 7.6 % in populations Negotin, Bujanovac and Dutch strain, respectively). Direct treatment of wasps at their pupal stage (LC50, 300 mg a.i./l) reduced total parasitism of Negotin wasps (by 8 %), and reduced ri levels, but the reduction was significant only for the Bujanovac (by 6.7 %) and Negotin (by 4.6 %) populations. Juvenile development of the parasitoid in treated pupae was significantly extended (by 0.3-1.1 days), compared to control wasps. The implications of these results on integrated control of the greenhouse whitefly are discussed.

Abundance, seasonality and parasitism of Diaspididae (Hemiptera) on olive trees

Olive culture is a recent activity in Rio Grande do Sul, Brazil with little information on its scale insects. Abundance and seasonality of armored scale insects (Hemiptera, Diaspididae) and their parasitism was evaluated in olive orchard, Olea europaea L., cultivar Arbequina, in Caçapava do Sul (30°30′43″ S, 53°29′27″ W), RS, Brazil. Samples were monthly collected from April 2012 to March 2013. At each occasion 20 trees were drawn and, from each quadrant of their canopies (northern, southern, eastern and western) two branches (20 - 30 cm - length and contained at least 20 leaves) were randomly removed, respectively from the inner part and the outer part of the canopy. We found five species of Diaspididae, Aonidiella aurantii (Maskell), Hemiberlesia cyanophylli (Signoret), Acutaspis paulista (Hempel), Aspidiotus nerii Bouché and Melanaspis obscura (Comstock). It was not found an unique pattern of abundance, indicating that these species respond differently to temperature variations between seasons. The armored scale insects were evenly distributed among quadrants. Only H. cyanophylli showed differences in abundance between the inner and outer branches. We registered parasitism in all Diaspididae species; the total parasitism rate was 9.78%.

COMPATIBILIDADE DE MILHO TRANSGÊNICO COM O PARASITOIDE Trichogramma pretiosum

RESUMO - Plantas de milho transgênicas que expressam toxinas da bactéria Bacillus thuringiensis (Bt) são uma alternativa para o controle de insetos-praga na cultura. No entanto, estas toxinas podem ser encontradas no pólen do milho, e organismos não alvo, como os inimigos naturais, podem ser prejudicados. Assim, o objetivo deste trabalho foi avaliar o efeito do pólen de três híbridos de milho transgênicos sobre parâmetros biológicos de adultos do parasitoide de ovos Trichogramma pretiosum em condições laboratoriais. Fêmeas recém-emergidas de T. pretiosum foram individualizadas em tubos de Duran contendo como alimento mel acrescido do pólen dos híbridos de milho transgênico AG 8011 YG (Cry1Ab), AS 1551 VT PRO (Cry1A. 105 + Cry 2Ab2) e Status Viptera (Vip3Aa20), e de seus respectivos isogênicos convencionais. Diariamente, foram ofertados, em cada tubo, ovos de Anagasta kuehniella para parasitismo. Os parâmetros avaliados foram: longevidade das fêmeas expostas ao pólen, taxa de parasitismo total, taxa de emergência e razão sexual da progênie. Os híbridos transgênicos: AG 8011 YG (Cry1Ab), AS 1551 VT PRO (Cry1A. 105 + Cry 2Ab2) e Status Viptera (Vip3Aa20), bem como seus isogênicos convencionais, não causaram efeitos deletérios sobre a longevidade e capacidade de parasitismo das fêmeas de T. pretiosum expostas aos respectivos pólens. A emergência e razão sexual da progênie também não foram negativamente afetadas, possibilitando assim a compatibilização dos transgênicos avaliados com o controle biológico natural e aplicado exercido por este parasitoide.Palavras-chave: Bacillus thuringiensis, transgenia, manejo integrado de pragas, controle biológico, Zea mays.COMPATIBILITY OF TRANSGENIC CORN WITH THE PARASITOID Trichogramma pretiosumABSTRACT - Transgenic corn expressing Bacillus thuringiensis (Bt) toxins is an alternative for pest control in corn fields. However, some non-target organisms such as natural enemies can be impaired by corn pollen containing toxins. Therefore, the aim of this work was to evaluate the effect of the pollen from three transgenic corn varieties on biological parameters of the egg parasitoid Trichogramma pretiosum under laboratorial conditions. Emerged females of T. pretiosum were placed into Duran tubes and fed with honey + pollen of corn hybrids AG 8011 YG (Cry1Ab), AS 1551 VT PRO (Cry1A. 105 + Cry 2Ab2) and Status Viptera (Vip3Aa20), as well as their respective isogenic. Daily, eggs of Anagasta kuehniella were offered in each tube for parasitism. The parameters evaluated were longevity of females exposed to pollen, total parasitism, progeny emergency and sex ratio. The transgenic hybrids AG 8011 YG (Cry1Ab), AS 1551 VT PRO (Cry1A. 105 + Cry 2Ab2), Status Viptera (Vip3Aa20) and their isogenic showed no deleterious effect on longevity and parasitism capacity of T. pretiosum females exposed to respective pollen. Emergency and sex ratio from progeny were also not adversely affected, thus enabling the compatibility of the evaluated transgenic with biological control by this parasitoid. Keywords: Bacillus thuringiensis, transgenes, integrated pest management, biological control, Zea mays.

Complex ecological relationships among an assemblage of indigenous hymenopteran parasitoids, the exotic European woodwasp (Sirex noctilio; Hymenoptera: Siricidae), and a native congener

We collected naturally infested Pinus resinosa Aiton (Pinaceae) and P. sylvestris Linnaeus to investigate phenological patterns and quantify parasitism by a suite of native hymenopteran parasitoids on two woodwasps (Hymenoptera: Siricidae): the invading non-native European woodwasp, Sirex noctilio Fabricius, and a co-colonising native, S. nigricornis Fabricius. We sampled a total of 76 trees from two field sites in 2010 and seven sites in 2011. In raw abundance, S. noctilio outnumbered S. nigricornis by 2:1 in 2010 and by 7.5:1 in 2011. We collected the egg/early instar parasitoid, Ibalia leucospoides ensiger Norton (Hymenoptera: Ibaliidae); four species of Rhyssinae (Hymenoptera: Ichneumonidae) late larval parasitoids; and Pseudorhyssa nigricornis (Ratzeburg) (Hymenoptera: Ichneumonidae), a cleptoparasitoid of rhyssines. Variation in siricid and parasitoid species assemblage and abundance was explained primarily by site, with tree-level factors playing a secondary role. Parasitism was significantly lower in P. sylvestris (13.6%±4.1 SE), a naturalised pine from Europe, than in the native P. resinosa (28.5%±5.0). Total parasitism was 27.6%±5.0 in 2010 and 20.9%±4.7 in 2011. This study represents the most robust analysis of the diverse woodwasp and parasitoid assemblage infesting pines in North America.

Effects of host and foundress density on reproductive strategy of Diaeretiella rapae

The reproductive fitness of a parasitoid depends on the oviposition decisions of a female in response to competition The present study investigated the oviposition and sex ratio of offspring produced by the parasitic wasp Diaeretiella rapae while competing with other conspecific females and at different host densities The number of Brevicoryne brassicae nymphs parasitised by female D rapae increased with the number of nymphs offered to them However the proportion of nymphs parasitised by the female decreased when nymph density was high The proportion of fertilised eggs oviposited by females decreased when nymph density increased An increase in the number of foundresses (females ovpositing together) increased the total parasitism but the contribution of each female (the number of nymphs each female parasitised) decreased Smaller proportions of female offspring were produced when females were competing for the same hosts The results of this study suggest that both host and foundress densities asymmetrically affect progeny production and sex allocation in this species

Parasitism Capacity of Trichogramma pretiosum and Trichogramma acacioi (Hym.: Trichogrammatidae) on eggs of Sitotroga cerealella (Lep.: Gelechiidae)

The objective of this work was to evaluate the parasitism capacity of Trichogramma pretiosum Riley and T. acacioi Brun, Moraes and Soares (Hymenoptera: Trichogrammatidae) in eggs of the alternative host Sitotroga cerealella (Olivier) (Lepidoptera: Gelechiidae) aiming to use both species in biological control programs of Nipteria panacea Tierry-Mieg (Lepidoptera: Geometridae). The parasitism rhythm and total parasitism of these parasitoid species were affected by the temperature with higher values during the first 24 h of their life. Parasitism period was longer for T. pretiosum and T. acacioi at the lowest temperature.

Parasitism of Diamondback Moth (Lepidoptera: Plutellidae) Larvae by Cotesia plutellae (Hymenoptera: Braconidae) and Diadegma insulare (Hymenoptera: Ichneumonidae) in Cabbage Fields after Inundative Releases of C. plutellae2

Cocoons of Cotesia plutellae (Kurdjumov) were released for nine consecutive wk along the margins of two commercial cabbage (Brassica oleracea var. bravo L.) fields near Bunnell, Flagler Co., FL, in spring 1996. The larval parasitism of diamondback moth, Plutella xylostella (L.), by C. plutellae and by the native parasitoid Diadegma insulare (Cresson) was evaluated in release fields and in nearby cabbage fields using two methods-sentinel collard (Brassica oleracea var. acephala L.) or sentinel cabbage plants and non-sentinel plants. Total parasitism of diamondback moth larvae on sentinel plants in the release and adjacent fields was 35.7%. There were no significant differences in the level of parasitism by C. plutellae among sentinel plant locations within the release fields. In non-release fields, parasitoids spread as far as 1,500 m from the nearest release site during the release period, but parasitism of larvae on sentinel plants decreased as the distance from the release area increased. Parasitism of diamondback moth larvae by D. insulare was 8.3% in C. plutellae release and adjacent fields, but 14.6% in the nearby fields. Sampling of non-sentinel cabbage plants for diamondback moth larvae demonstrated a total of 37.4% larval parasitism by C. plutellae in the release and adjacent fields, similar to that recorded on sentinel plants. However, C. plutellae were detected only as far as 800 m from the release site on non-sentinel cabbage plants, and total parasitism in the dispersal fields also was very low. Diadegma insulare contributed only 1.1% parasitism of larvae sampled from non-sentinel plants in all cabbage fields. Cotesia plutellae was more effective than D. insulare in attacking diamondback moth larvae in this study where field populations of diamondback moth were low (<0.1 larva per cabbage plant).

FINAL-INSTAR LARVAE OF NATIVE PUPAL PARASITES AND HYPERPARASITES OF OPEROPHTERA SPP. (LEPIDOPTERA: GEOMETRIDAE) ON SOUTHERN VANCOUVER ISLAND

Three native species of parasites and 3 hyperparasites were reared from pupae of the European winter moth, Operophtera brumata (L.), and the Bruce spanworm, O. bruceata (Hulst), collected in the Victoria area of Vancouver Island, British Columbia, in 1981. Two of the pupal parasites also attacked other species of Geometridae. Two species of hyperparasites attacked Cyzenis sp., and the third parasitized ichneumonid primary parasites of Operophtera spp. The hyperparasites may have a negative impact on the biological-control agents, Cyzenis albicans (Fall.) and Agrypon flaveolatum (Grav.). Total parasitism by pupal parasites of the Operophtera host complex was about 4%. Descriptions and illustrations of cephalic structures of final-instar larvae of the parasites and a key for their separation are given.

WITHIN AND BETWEEN TREE VARIATION OF LIVE AND PARASITIZED DOUGLAS-FIR TUSSOCK MOTH, ORYGIA PSEUDOTSUGATA (LEPIDOPTERA: LYMANTRIIDAE), COCOONS ON WHITE FIR IN CENTRAL CALIFORNIA AND ITS IMPLICATIONS FOR SAMPLING

The distribution of Douglas-fir tussock moth, Orgyia pseudotsugata (McD.), cocoons was studied within and between the crowns of white fir, Abies concolor ((Gord. and Glend.) Lindl.), at six locations in the central Sierra Nevada Mountains of California. The within tree, between tree, and between plot distribution of cocoons in the crown, categorized by sex, mortality (including parasitization), and stage (larva or pupa) were analyzed. Only cocoons containing female pupae varied in their distribution within the tree and they were concentrated in the bottom third of the live crown but their densities at any one level bore little relation to those in the other levels within the crown. Cocoon density varied significantly between plots and between trees within plots. Total parasitism did not vary significantly between plots. The variable within tree distribution of cocoons containing female pupae and their increased percentage parasitism relative to those containing male pupae, suggested that the live crown should be stratified. A sample unit consisting of two branches selected from the midpoint of each of the three crown levels (total: 6 branches) sampled approximately 5% of the live crown of white fir. The relation between the number of sample trees and mean cocoon density at three levels of precision is provided.