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This work studied 17 insecticides belonging to nucleopolyhedrovirus (NPV), Bacillus thuringiensis (Bt kurstaki and Bt aizawai), benzoylureas (insect growth regulators [IGRs]), carbamates, organophosphates, spinosyns, and diamides against larvae of Helicoverpa armigera (Hübner), invasive species in the South American continent. Larvae of different instars were fed for 7 d with untreated or insecticide-treated diets. Mortality was recorded daily for 7 d, and surviving larvae were individually weighed on the seventh day. The NPV and Bt insecticides caused 100% mortality of first-instar larvae and first-instar and second-instar larvae, respectively. However, both NPV and Bt-based products caused low mortality of third-instar larvae and did not kill older larvae. The IGR lufenuron was highly effective against all three ages of larvae tested, whereas teflubenzuron and triflumuron produced maximum 60% mortality of second-instar larvae and lower than 50% to older larvae. Thiodicarb, chlorantraniliprole, indoxacarb, chlorpyrifos, and chlorfenapyr, irrespective of tested age, caused 100% mortality of larvae, with the last two insecticides reaching 100% mortality within 2 d of feeding on the treated diet. Flubendiamide caused lower mortality but significantly affected the weight of surviving larvae, whereas neither spinosad nor methomyl produced significant mortality or affected the weight of larvae. Based on the results, the age of H. armigera larvae plays an important role in the recommendation of NPV and Bt insecticides. Furthermore, there are potential options between biological and synthetic insecticides tested against H. armigera, and recording larval size during monitoring, in addition to the infestation level, should be considered when recommending biological-based insecticides to control this pest. [ABSTRACT FROM AUTHOR]

A multi-residue method was developed to determine different types of pesticides in soils. An extraction with pressure and temperature, through accelerated solvent extraction (dichloromethane:acetone, 50:50, v/v). The pesticides were determined by gas chromatography with several selective detectors: electron capture detector, pulsed flame photometric detector and thermionic specific detector. The following parameters were determined: limit of detection, limit of quantification, equipment linearity (working interval), method linearity as well as, method accuracy and precision. The average recoveries ranged between 76 and 106%, with the exception of chlorothalonil, which had an average recovery of 46%. Additionally, detection limits from 0.9 to 7.6 ng g-1 and the quantification limits from 3.00 to 25.47 ng g-1 were estimated. In terms of linearity and precision, the results obtained were in the ranges considered adequate (R² ≥ 0.98 and coefficient of variation (CV) ≤ 20%), with the exception of aldrin (R² = 0.946, CV = 35.79%), lindane (R² = 0.917, CV = 32.91%) and chlorothalonil (R² = 0.8184, CV = 81.35%). The proposed method was used to evaluate pesticides in real soil samples, detecting concentrations over 1000 ng g-1 for some pesticides. The method was correctly validated and provided for the rapid determination of pesticides in soil. [ABSTRACT FROM AUTHOR]

Release of natural enemies in commercial fields is challenging and has been inconsistent in the results achieved. This work discusses the augmentative releases of Trichogramma pretiosum to control the cotton leafworm (CLW) Alabama argillacea and also examines the parasitoid–host interaction under grower field conditions. The treatments consisted of fields with and without releases of T. pretiosum set up in Primavera do Leste and Campo Verde Counties, MT, Brazil, during three different seasons (2003 and 2004 dry and 2004 regular summer seasons). Trichogramma wasps were weekly released in the treated fields throughout the entire sampling period (14–15 week period) at a rate of 100 000 wasps per hectare. One-way repeated measures analysis of variance was performed for the number of parasitized eggs, followed by a meta-analysis procedure to determine the contribution of T. pretiosum release on overall parasitism. In addition, regression analysis was conducted with each season’s data sets to study the relationship of the host density and parasitism response by T. pretiosum. The overall results of Trichogramma augmentative releases did not result in significant increase of CLW egg parasitism beyond the natural parasitism in the areas studied. However, based on Cohen’s d effect sizes from the meta-analysis, the parasitism rate was greater in fields under T. pretiosum releases during four out of 15 weeks surveyed. The parasitism of CLW eggs by T. pretiosum exhibited host density-dependence only in one out of three seasons surveyed. These findings are encouraging as they are evidence that T. pretiosum is able to maintain a considerable level of parasitism under commercial field conditions, highlighting their potential value in large-scale commercial areas of cotton as previously found at the small and diverse farming scale. Future studies should address the potential of early-season, low density releases of the parasitoid. [ABSTRACT FROM AUTHOR]

The coconut mite, Aceria guerreronis (Acari: Eriophyidae) and the coconut moth, Atheloca subrufella (Lepidoptera: Phycitidae), exploit the same habitat—meristematic region underneath the coconut fruit perianth. The coconut fruit perianth, however, is a tight structure allowing free colonisation of the meristematic region of the fruit only by small arthropods such as the eriophyid and tarsonemid mites. Fruits infested by the mites develop different levels of necrosis around the perianth providing access to colonising larvae of the coconut moth, which bore the fruit under the perianth resulting in fruit abortion. Based on field observations, we hypothesise that A. subrufella will colonise coconut fruits only if they exhibit damage on the perianth such as the necrosis caused by the coconut mite. Fruits with and without necrosis were collected from different production areas located in three different states along the Brazilian Atlantic coast and inspected for infestation with coconut moth larvae. In the laboratory, coconut fruits with and without necrosis were offered to moths for oviposition preference and tested for colonisation by neonate and third instar larvae. The results showed that the moths showed no preference for fruits with or without necrosis for oviposition and, hence, neonate larvae have to go under the perianth bract to reach the meristematic region of the fruit. However, neonate larvae were unable to colonise fruits without necrosis (0%) compared to 23% and 60% of fruit colonisation success when exhibiting mite necrosis or mechanical damage, respectively. Similar results were found with respect to older coconut moth larvae. Thus, the data support the hypothesis that the indirect interaction through previous fruit colonisation and necrosis caused by the coconut mite allows the larvae of A. subrufella to be a key pest of coconut fruits. [ABSTRACT FROM AUTHOR]

The modified population dynamics of pests targeted by the Cry1Ac toxin in Bacillus thuringiensis (Bt) transgenic cotton (Bt cotton) and possible reduced insecticide use in these transgenic varieties may exert a variety of effects on ground-dwelling predator communities. A survey of ground-dwelling arthropods was carried out weekly each of 3 years (during the cropping season) in commercial Bt and non-Bt cotton fields. Sixty-five taxa of ground-dwelling arthropods (carabids, cicindelines, staphylinids, dermapterans, heteropterans and araneids) of importance for cotton pest management were recorded in the survey. Species abundance and dynamics across seasons were evaluated with univariate analysis of variance for higher taxa or multivariate principal response curve analysis for the whole community of 65 taxa. Diversity and richness indices and cumulative species curves also were calculated. The analyses demonstrated no differences in the ground-dwelling arthropod communities between cotton types. One araneid species, Pardosa pauxilla, comprised ∼80% of all araneids, Labidura riparia comprised ∼96% of all dermapterans, Megacephala carolina comprised ∼97% of cicindelines and four carabid species ( Selenophorus palliatus, Apristus latens, Harpalus gravis and Anisodactylus merula) comprised ∼80% of carabid species. M. carolina outnumbered all other collected species in each of the 3 years. When only predatory carabid species were considered, A. merula, Calosoma sayi, Harpalus pennsylvanicus and Stenolophus ochropezus were predominant and numbers trapped were similar between cotton types. The abundance of dermapterans, staphylinids, araneids and heteropterans varied among sample dates and across seasons but did not differ between cotton types. The frequent capture of M. carolina, S. palliatus and P. pauxilla in all fields and seasons in both cottons suggests that these species may be important for monitoring further changes in local communities as result of agricultural practices. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate site preference of tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), developmental stages on processing tomatoes. Eggs, first- and fourth-instar-caterpillars and pupae, damaging processing tomatoes var. IPA-5, at selected stages (I—before flowering, II—before fruits developed, and III—after fruits developed) were examined. Natural oviposition was studied by releasing 3-day-old T. absoluta moths (ca 20–30) in cages under conditions of darkness. At stage I, the females chose the under-side of the leaf for oviposition in the apical part of the plant canopy. However, the number of eggs laid on the under-side of the leaf surface andpetioles were similar in the three plantparts. At stages II and III, the means of eggs laid on either the upper- or under-side of leaf surfaces was similar between apical and median plant parts. Eggs recorded on leaf petioles were equal for the three parts (apical, median, basal). Higher first- and fourth-instar-caterpillars numbers were observed on the apical and median plant parts for the three developmental stages. However, fourth-instar-caterpillars were distributed equally on the three plantparts in stage III. Higher pupation at stage I was observed onthe apical part, while at stages II andIII it was similar among the three plant parts. For all stages, the pupation was higher on leaves, followed by soil, mainstems and fruit (stage III), respectively. Stage III showed a higher number of pupae on the mainstem compared with stages I and II. [ABSTRACT FROM AUTHOR]

Developmental rates, egg and nymph survival and adult reproduction of Podisus nigrispinus (Dallas) (Het., Pentatomidae) were investigated under six fluctuating temperatures and night-day regimes with a photoperiod of 14 h light: 10 h dark compared with a check temperature of 27 ± 1.5°C. Lower development threshold temperatures for egg, nymphal stage and from egg to adult were estimated at 13.70, 11.96 and 12.68°C with a requirement, respectively, of 54.34, 284.25 and 327.13 degree-days. The highest egg-adult development rate was achieved at 25-35°C. At 10-20°C only 7.0% of nymphs reached adult stage, whereas at 27, 15-25 and 17-27°C, 93.0, 87.3 and 91.1% adult emergence was achieved, respectively. The females that emerged at 10-20°C laid no eggs, while those ar 25-35, 15-25, 17-27 and 27°C produced a total of 92.1, 453.2, 415.0 and 325.0 eggs, respectively. Results for threshold temperature and thermal requirement were approximately those reported at constant temperatures by other researchers, while the reproductive parameters of P. nigrispinus were better at intermediate temperatures ranging from 15-25 to 20-30°C. [ABSTRACT FROM AUTHOR]

The literature on masculinity and gender roles in American life has mostly over-looked Latino men, or has stereotyped them by means of a distorted concept of machismo. A reconceptualization of masculinity and machismo among Puerto Rican men is presented, based on a multidimensional view of their historical and current sociocultural reality. Relevant clinical and social services for Puerto Rican men are discussed and directions for future research are suggested. [ABSTRACT FROM AUTHOR]

The long-lived polygynandrous ladybird beetle Tenuisvalvae notata (Mulsant) found in Brazil was evaluated in the laboratory for the effects of multiple mating and aging on its reproductive performance. This species is native to South America and is an important predator of mealybugs. Specifically studied were partner choice, female reproductive success, adult longevity, male virility, and offspring development. Young (5-10 days old) and older virgin females (95-100 days old) were subjected to either a single mate or multiple mating with the same or different males of various mating status (virgin or previously mated once, twice, and thrice). Results revealed a preference in both genders to mate with previously known partners. Additionally, younger females had higher fecundity and greater longevity when mated only once in comparison to those mated multiple times. Fecundity, fertility, and offspring development were similar across the treatments regardless of the number of mating or male mating history. Fecundity and fertility decreased throughout the oviposition period regardless of mating treatment.

Natural enemies are exposed to insecticide sprays for herbivorous species and may evolve field resistance to insecticides. Natural enemies selected for resistance in the field, however, are welcome for pest control. The susceptibility of 20 populations of Eriopis connexa from various crop ecosystems to λ-cyhalothrin was tested. Three bioassays were conducted: (i) topical treatment with lethal dose (LD)50 previously determined for populations considered standard for susceptibility (LD50S) and for resistance (LD50R) to λ-cyhalothrin at technical grade; (ii) dose-mortality assay to calculate the LD for populations exhibiting significant survival to the LD50R; and (iii) determination of survival when exposed to dried residues at field rates. Among the 20 tested populations, seven populations did not survive or survival rates were lower than 10% when treated with LD50R; three populations survived >20%, but lower than 50%; while ten populations exhibited equal or greater survival rates compared with the 50% expected survival for the LD50R. Thus, these ten populations were subjected to dose-mortality response, and the LD50 values varied from 0.046 to 5.44 µg a.i./insect with resistance ratio of 8.52- to 884.08-folds. Adults from these ten populations that were ranked as resistant according to the LD50R exhibited survival from 44.5 to 100% exposed to the lowest and from 38.8 to 100% exposed to the highest field rates of λ-cyhalothrin, respectively. Otherwise, the remaining ten populations ranked as susceptible according to the LD50R showed survival from 3.3 to 56% exposed to the lowest and from 0 to 17.7% exposed to the highest field rates of λ-cyhalothrin, respectively. Therefore, 50% of the tested E. connexa populations exhibited field-evolved resistance to λ-cyhalothrin and the use of a discriminatory LD50 for resistance matched the survival obtained when exposed to the insecticide field rates.

The ladybird beetle, Eriopis connexa (Germar) (Coleoptera: Coccinellidae), is one of the commonest predators of aphids (Hemiptera: Aphididae) in the cotton agroecosystem and in many other row and fruit crops in Brazil, and has been introduced into other countries such as the USA for purposes of aphid control. In addition, the boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae) is the most serious cotton pest where it occurs, including Brazil. Controlling boll weevils and other pests such as cotton defoliators still tends to involve the intense application of insecticides to secure cotton production. The pyrethroid insecticide lambda-cyhalothrin (LCT) is commonly used, but this compound is not effective against aphids; hence, a desirable strategy would be to maintain E. connexa populations in cotton fields where LCT is applied. Using populations of E. connexa resistant (Res) and susceptible (Sus) to LCT, we compared behavioural responses on treated cotton plants and under confinement on partially and fully treated surfaces, and assessed the insects' survival on treated plants compared with that of the boll weevil. The E. connexa resistant population caged on treated plants with 15 and 75 g a.i. ha-1 exhibited ≫82% survival for both insecticide concentrations compared with ≪3% and ≪17% survival for susceptible E. connexa populations and boll weevils, respectively. The response of E. connexa Res and Sus populations when released, either on the soil or on the plant canopy, indicated avoidance towards treated plants, as measured by elapsed time to assess the plant. When compared with susceptible individuals, resistant ones took longer time to suffer insecticide knockdown, had a higher recovery rate after suffering knockdown, and spent more time in the plant canopy. Based on behavioural parameters evaluated in treated arenas, no ladybird beetles exhibited repellency. However, irritability was evident, with the susceptible population exhibiting greater irritability compared with the resistant population and a subgroup comprising resistant individuals that had recovered from knockdown. The outcomes for the E. connexa Res population indicate a promising strategy for its maintenance when using the insecticide LCT in integrated pest management schemes to control boll weevil or other non-target pest of ladybird beetles in cotton fields.

Rearing Technique and Biological Traits of Atheloca subrufella (Hulst) (Lepidoptera: Phycitidae) in Coconut Fruits. Larvae of the coconut moth Atheloca subrufella (Hulst) develop in flowers and fruits of coconut, Cocos nucifera, causing precocious abscission of these structures and, hence, yield decrease. This work studied a feasible and suitable rearing technique for A. subrufella using fruits of coconut. We first determined the appropriate density of larvae to be reared per coconut fruit (among two, three, four or five larvae) and later tested the suitability of this rearing technique for three successive generations. The storage of egg and pupal stages during 0, 5, 10 and 20 days was also studied at 12ºC. Based on the fertility life table parameters, the best results were achieved by rearing two or three larvae per fruit as they yielded the best net reproductive rate and intrinsic rate of population increase. In addition, eggs and pupae of A. subrufella can be stored at 12ºC up to five days with viability higher than 90%. Adult moths emerged from pupae stored for five days at 12ºC produced an average of 219.4 eggs and lived 18.8 days. Storage periods for eggs and pupae over 10 days significantly reduced egg viability and adult fecundity, respectively. Thus, the technique in here described was shown to be suitable for the continuous rearing of A. subrufella in laboratory conditions.

The reproductive parameters of Telenomus podisi, Trissolcus brochymenae (Hymenoptera: Scelionidae) and Ooencyrtus sp. (Hymenoptera: Encyrtidae) were studied for three generations on their natural host Podisus nigrispinus (Dallas, 1851) (Hemiptera: Pentatomidae). A parasitism rate of 10 eggs/day/species was used under laboratory conditions of 27 +/- 1 degrees C, 60 +/- 10% RH and 14 h of photophase. No significant differences were detected between generations in terms of net reproductive rate (Ro), intrinsic rate of natural increase (rm), generation time (T) and the effect of doubling time on population increase (DT). However, T. podisi and T. brochymenae had significantly higher Ro and rm values, and lower T and DT values, with rm 1.59 and 1.50 times higher than Ooencyrtus sp., respectively. In addition the former species also had shorter egg-adult period, greater longevity of females and reproduction period than the other species. These results confirm the greater reproductive potential of T. podisi and T. brochymenae, which are commonly found parasitizing P. nigrispinus.