Conventional Insecticide Treatment Research Articles

Enhancing pest management - Utilizing supplementary food spray to harness predatory insects against fall armyworm in maize crop of Vinh Phuc Province, Vietnam

The effect of supplementary food spray on the fall armyworm (Spodoptera frugiperda) and beneficial insects (predominantly predatory insects) was studied in commercial maize field experiments from 2020 to 2022. The food spray formulation was developed from local ingredients in Vietnam, both with and without neem extract. The sugar-based rice dough product attracted and sustained beneficial insects, significantly reducing fall armyworm populations. Compared to conventional insecticide treatments, the net margin achieved in plots treated with food spray was higher ($3,467) to $3,394 in the conventional insecticide-treated plots demonstrating its economic viability (1 AUD=17.28 VND). Our study observed an average predator-to-prey ratio of 9.2:1 per plant in the food-spray-treated plots, and that was effective in managing the fall armyworm throughout the season. We propose that this ratio can serve as a valuable parameter and decisionmaking tool in food spray-based Integrated Pest Management (IPM) programs against fall armyworm in maize fields. Therefore, we suggest that food sprays can be incorporated into IPM strategies to successfully manage fall armyworm infestation in maize crop.

SUSTAINABLE CONTROL OF CODLING MOTH, CYDIA POMONELLA L. IN SOME APPLE ORCHARDS OF BULGARIA

The codling moth (CM), Cydia pomonella L., is the key pest of pome fruits in Bulgaria. Reduction of pesticide use is an important consideration for human health as well as for conservation of biodiversity. Environmentally friendly methods such as semiochemicals are among the most promising. These trials were carried out during the years 2020 and 2021 in southeast Bulgaria to test the effectiveness of microencapsulated sprayable pheromones in apple orchards using CIDETRAK® CM MEC (pheromone) liquid formulations as well as the effectiveness of mating disruption (MD) using CIDETRAK® CMDA COMBO™ MESO™ -A dispensers at rate of 80 dispensers per ha. Monitoring of CM flights was implemented using pheromone or pheromone and kairomone lures with traps during the years of the study. The traps baited with standard PHEROCON® CM L2 lures were changed at 4-week intervals. We also used PHEROCON® CMDA COMBO™ - P + AA lures, which is a new product developed by Trécé Inc., USA for use in orchards with MD. The traps baited with PHEROCON® CM DA COMBO - P + AA lures were changed at 8-week intervals. The damage in the treatment plot increased slowly over time and even in late cultivars, fruit damage by CM was below the economical threshold from 0.1 to 0.2% in both years of the study. Comparatively, ten insecticide treatments were applied to the reference orchard located in the region during the season, targeting CM and other pests. Correspondingly, fruit damage at harvest in the reference orchard by CM was from 2.2 to 2.5%. The significance of differences in the damage rate between the trial and the reference orchard was estimated by Chi-square tests. These new products developed by Trécé Inc., USA can be used in organic farming and fits perfectly into any IPM system. The use of CIDETRAK® CM MEC and CIDETRAK® CMDA COMBO™ MESO™ - A dispensers will help growers to decrease the number of chemical treatments in the field. Introduction of these products for pest management should result in reduction of the use of conventional chemical insecticide treatments, thus resulting in less environmental pollution and improved food quality.

Attract and kill: spinosad containing spheres to control onion maggot (Delia antiqua).

Onion maggot (Delia antiqua) is a pest of onions worldwide. Current means of managing this pest rely heavily on prophylatic insecticide treatments at planting. These options may not be viable in organic production systems or situations where insecticide-resistant populations occur. Here we explore the efficacy of an attract and kill strategy for control of D. antiqua evaluating the ability of attractive, spinosad containing spheres to kill adult D. antiqua and reduce crop losses. Spinosad containing spheres were able to consistently kill D. antiqua adults over the course of the field season (mortality range: between 49% and 59% on average). Pairing spinosad spheres with Delia Lure increased efficacy by 72% compared with the spheres alone. Performance of this attract and kill strategy also can reduce damage by D. antiqua larvae in the field, but it did not achieve a level of control comparable to the level provided by a conventional insecticide treatment. Implementation of this attract and kill strategy could be a valuable tool in situations where conventional pesticides are either not available or desired, where additional control techniques are needed, or to provide a season-long option for control of D. antiqua populations. © 2020 Society of Chemical Industry.

Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV): Natural occurrence and efficacy as a biological insecticide on young banana plants in greenhouse and open-field conditions on the Canary Islands.

Chrysodeixis chalcites, an important pest of banana crops on the Canary Islands, is usually controlled by chemical insecticides. The present study aimed to evaluate the efficacy of the most prevalent isolate of the Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV, Baculoviridae) as a biological insecticide. Overall the prevalence of ChchNPV infection in C. chalcites populations was 2.3% (103 infected larvae out of 4,438 sampled), but varied from 0–4.8% on Tenerife and was usually low (0–2%) on the other islands. On Tenerife, infected larvae were present at 11 out of 17 plantations sampled. The prevalence of infection in larvae on bananas grown under greenhouse structures was significantly higher (3%) than in open-field sites (1.4%). The ChchNPV-TF1 isolate was the most abundant and widespread of four genetic variants of the virus. Application of 1.0x109 viral occlusion bodies (OBs)/l of ChchNPV-TF1 significantly reduced C. chalcites foliar damage in young banana plants as did commonly used pesticides, both in greenhouse and open-field sites. The insecticidal efficacy of ChchNPV-TF1 was similar to that of indoxacarb and a Bacillus thuringiensis (Bt)-based insecticide in one year of trials and similar to Bt in the following year of trails in greenhouse and field crops. However, larvae collected at different time intervals following virus treatments and reared in the laboratory experienced 2–7 fold more mortality than insects from conventional insecticide treatments. This suggests that the acquisition of lethal dose occurred over an extended period (up to 7 days) compared to a brief peak in larvae on plants treated with conventional insecticides. These results should prove useful for the registration of a ChchNPV-based insecticide for integrated management of this pest in banana crops on the Canary Islands.

Efficacy of BotaniGard (<i>Beauveria bassiana</i>) Against Whiteflies on Poinsettia and Dahlia

Efficacy of the entomopathogen fungus, <i>Beauveria bassiana</i> (BotaniGard) was compared with conventional insecticides against whiteflies on Poinsettia (<i>Euphorbia pulcherrima</i>) and Dahlia (<i>Dahlia coccinea</i>) in Maranque plant located at Doni in Eastern Shoa zone of Ethiopia between December 2010 and March 2011. The experimental site measuring 1250 m^² was divided in 6 bays. Three bays in alternative fashion were allocated for treatment with the test pesticide, BotaniGard and the other three for spraying with the conventional insecticides according to the routine practice of the farm. BotaniGard was applied at the concentration of 0.15% by mixing 150 ml of the product with 100 l of water weekly for the first ten weeks and twice weekly thereafter until the termination of the experiment. Mean whitefly number per treatment was calculated to examine population fluctuation in adjacent BotaniGard and control treatments of both Dahlia and poinsettia. To assess presence of statistical differences in whitefly population between treatments as well as between plant species, a student t-test was used using counts recorded from each of the 12 cards per treatment at the different weeks. Population of whiteflies was generally low in both plant species until 17 January 2011 without appreciable difference in whiteflies number between the BotaniGard and the conventional insecticides. Whiteflies number increased after 17 January in both plant species and peaked on 7 February 2011. Pest population in BotaniGard treated bed was lower than conventional insecticides treated bed during this period in both plant species. Whiteflies population in Poinsettia fluctuated between 3.9 and 42 per trap compared to between 0.6 and 24.8 in Dahlia in the conventional insecticide treatment. On BotaniGard treated plot, whiteflies number fluctuated between 2.5 and 17.6 in poinsettia and between 1.8 and 12.5 in Dahlia. This difference between Dahlia and poinsettia was significant (P<0.05) in 5 out of 12 sampling dates in the conventional treatment and in 7 out of 12 weeks in BotaniGard treatment. Dahlia was less susceptible to whiteflies and BotaniGard resulted in lower number of whiteflies than the conventional insecticide treatment. Hence, BotaniGard may be used as a viable alternative to reducing the use of chemical insecticides in the management of whiteflies in green house produced plants.

Economic evaluation of biorational and conventional insecticides for the control of maize stem borer Chilo partellus (Swinhoe) in Zea mays

Maize borer, Chilo partellus (Swinhoe) is the chief limiting factor for higher corn production. Field trials to assess the efficacy of different insecticides against C. partellus were carried in district Ropar, Punjab. It was observed that significantly lesser leaf injury incidence was recorded in biorational treatment T1: chlorantriniliprole 18.5 SC (3.43 &amp; 4.23) in comparison to broad spectrum conventional insecticide treatment T3: Deltamethrin 2.8 EC (4.63&amp; 5.36) and T4 :Farmer’s practice 4.43 and 6.93. Whereas in plots with parasitoid application (T2), the leaf injury incidence was recorded to be 6.56 &amp; 7.86 during 2012 and 2013, respectively. Though T2 was statistically superior to control, however it was not at par with insecticide treatments. Furthermore similar trend was observed for dead hearts reduction in different treatments. It was recorded to be 3.16 and 3.90, 3.33 and 3.96, 3.53 and 3.96 in insecticide treatment plots T1, T3 and T4 respectively. The economic returns on the basis of marketable grain yield in insecticide treated plots was more in T1 followed by T3 and T4 (51.99, 49.58 and 48.51) in comparison to control (40.44) and biological control plots (46.75). Therefore experimental data revealed overall superiority of biorational pesticide in comparison to conventional insecticides for reduction in pest damage and economic returns. Hence the option of biorational for the control of maize stem borer not only justify safety to environment but also offers effective control of borer population in maize ecosystem due to its distinct chemical class and unique mode of action.

Control of the Tomato Leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), in Open-Field Tomatoes by Indigenous Natural Enemies Occurring in Israel.

The tomato leafminer, Tuta absoluta (Meyrick), had established in Israel by 2010, attacking both open-field tomatoes and greenhouse crops.We searched for its natural enemies in open-field tomatoes, and tried to determine their potential for controlling this pest. We surveyed the local natural enemies in open tomato fields and measured their impact on pest populations in an unsprayed field. We assessed the suppressive ability of the dominant hemipteran predator, Nesidiocoris tenuis Reuter, against T. absoluta under controlled laboratory conditions and evaluated the impact of its augmentation on T. absoluta control in open-field tomatoes. We found five natural enemy species:the predator, N. tenuis, two braconids, and two eulophids. Predation accounted for 64.5±9.2% (mean ± SE) of T. absoluta larval mortality, whereas parasitism accounted for 20.96±7.5%. Together, they eliminated the pest population at tomato harvest time. Under controlled conditions, predation by N. tenuis rose from 58 to 72% with increased density of T. absoluta, suggesting positive density dependence. The reduction of T. absoluta (83%) by N. tenuis was higher than that of Bemisia tabaci (32%), suggesting a preference of N. tenuis for T. absoluta. Augmentation of N.tenuis was as effective as conventional treatment insecticide treatment, and plant damage was low and did not seem to affect yield. Results indicate that reduced pesticide use enables indigenous natural enemies, particularly N.tenuis, to successfully control T. absoluta and prevent crop damage in open-field tomatoes.

The effect of pesticides and aqueous extracts of Azadirachta indica (A. Juss) and Jatropha carcus L. on Bemisia tabaci (Gennadius) (Homoptera: Aleyrididae) and Helicoverpa armigera (Hübner)(Lepidoptera: Noctuidae) found on tomato plants in Côte d’Ivoire.

Objective : The objective was to evaluate the effects of foliar application of Jatropha and neem aqueous extracts compared to a conventional insecticide treatment on the number of whitefly Bemisia tabaci ( Gennadius) and bollworm Helicoverpa armigera (Hubner), yield of tomatoes in plots and the potentials of using any of these aqueous extracts to control these insect pests. Methodology and results: the study was conducted in the region of Moronou (Bongouanou, Koffikro, CBC Kangandissou). The insecticides Decis 12 EC® and Cypercal 50 EC®, and neem and jatropha aqueous extract were used for tomato foliar treatment (neem and jatropha seeds 80 and 50g/L, neem leaves 67 g/L). The treatments of tomato plant plots with pesticides Decis® and Cypercal® showed similar yields of biopestcide made of neem and jatropha in Ahorosso (P=0.00), Bongouanou (P=0.07) and CBC Kangandissou (P=0.01) plots. All of these treatments reduced the number of Bemisia tabaci adults, reduced the number of Helicoverpa armigera larvae on tomato plants and increased number of fruits per plant, the fruit weight per plant and the yield. Conclusion and application of findings : Statistical analysis shows that aqueous extract of jatropha and neem seed 80 g/L and 50 g/L, and of neem leaves 67 g/L are as effective as pesticides Decis® and Cypercal® on Bemisia tabaci and Helicoverpa armigera. Consequently, these biopesticides increased the number of fruits per plant and yield. This result should enable use of aqueous extract of neem and jatropha seed and of neem leaves to protect tomato plants against Bemisia tabaci and Helicoverpa armigera at farm. Keywords : Bemisia tabaci; Helicoverpa armigera ; tomato crop; aqueous extract; biocontrol

Dual‐treatment autodissemination station with enhanced transfer of an insect growth regulator to mosquito oviposition sites

The Asian tiger mosquito, Aedes albopictus (Skuse), transmits important arboviral diseases and displaces native species. This peridomestic mosquito deposits eggs in natural and artificial containers. Container larval habitats tend to be cryptic and, therefore, difficult to reach by conventional insecticide treatments. We have developed an autodissemination station that transfers the insect growth regulator, pyriproxyfen, from the station to oviposition sites. Mosquitoes visiting the station become contaminated with an oil sticker followed by pyriproxyfen powder before exiting. In a room (31 m(3) ) bioassay a single station consistently achieved 100% Ae. albopictus pupal mortality against 10 oviposition containers. In a greenhouse (200 m(3) ) assay with two stations and 12 oviposition cups, 91.7% of the cups had been contaminated as shown, and 57.1% pupal mortality was recorded. Pyriproxyfen transfer was also detected by visualizing mosquito 'tarsal prints' using a fluorescent dye. The oil and pyriproxyfen powder dual-treatment station enhanced autodissemination efficacy by increasing toxicant attachment and retention on contaminated females. The autodissemination station offers a targeted, less environmentally damaging approach to manage cryptic container species.

Optimization of a Trap for Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) and Trials to Determine the Effectiveness of Mass Trapping

Management of the South American tomato leafminer, Tuta absoluta Meyrick, with insecticides has led to the widespread development of insect resistance. Mass trapping using traps baited with the female-produced sex pheromone is an attractive alternative for the management of this pest. The current study evaluated several commercial trap designs for capture of T. absoluta. Based on its small size and ease of handling, the most effective trap is a small plastic container with entry windows cut on the sides filled with motor oil over water. These traps are most effective when placed near ground level. Tests of septa containing 0.1 or 0.2mg of the pheromone (95:5) E4, Z8-14Ac/E4,Z8,Z11-14Ac were slightly more attractive than septa loaded with 0.5, 1.0, or 2mg during the first week of use, but the latter three loadings were slightly more attractive than the first two loadings after 9weeks. Ideal trap baits were loaded with 0.5mg of pheromone. Higher numbers of T. absoluta were captured near upwind borders of tomato fields suggesting that treatments against T. absoluta should be concentrated near upwind parts of fields. Comparisons of conventional insecticide treatment versus mass trapping to manage T. absoluta damage in three different test sites showed that even when initial captures in monitoring traps were high (>35 malestrap(-1)day(-1)), mass trapping at 48 traps/ha reduced leaf damage more efficiently than conventional insecticide treatment. Based on the typical insecticide recommendations against T. absoluta, mass trapping is an economically viable alternative.

The use of OLIPE traps as a part of a regional effort towards olive fly (&lt;i&gt;Bactrocera oleae&lt;/i&gt; Gmelin) control

The olive fruit fly, Bactrocera oleae Gmelin, is a key pest of olive fruit, causing up to 50% crop loss. Conventional insecticide treatments of B. oleae cause both a serious disruption of the biological equilibrium and environmental pollution. In order to improve the yield, quality, and farm income from oil olive varieties in the eastern Mediterranean, collaboration has been formed between Jordan, Israel, and the Palestinian Authority. Among the specific objectives set was the implementation of traps that are efficient, low-cost, and environmentally friendly. In 2008, the efficiency of the home-made OLIPE trap was compared with the commercial Fruitect trap in 11 locations in Jordan, Israel, and the Palestinian Authority, and the presence of the olive fly as well as infestation levels was compared. The insignificant influence found for the two traps in all parameters measured could have resulted from the small plots, variability among study sites, low infestation level, or actual inefficiency. However, thi...

Comparison of biological and conventional insecticide treatments for the management of the pineapple fruit borer, Strymon megarus (Lepidoptera: Lycaenidae) in Costa Rica

Carbaryl is currently one of the most commonly used insecticides for the control of the pineapple fruit borer, Strymon megarus (Godart), in commercial pineapple production. To evaluate more sustainable biological alternatives to conventional insecticides, three microbial and one botanical insecticide were studied. Beauveria bassiana, Metarhizium anisopliae, Bacillus thuringiensis ( Bt) and a plant extract from Quassia amara were compared with carbaryl in replicated field trials in Costa Rica during 2005 and 2006. In both years of testing, the untreated control received over 50% fruit damage from S. megarus. Bt and carbaryl provided the highest level of control and the lowest level of fruit damage compared to all other treatments. Based on the results of this study, Bt appears to be an acceptable biological alternative to the conventional insecticide (carbaryl) for control of S. megarus on pineapple. In addition, Bt was the least expensive treatment used in this study.

Living ground covers for management of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) and tomato yellow mottle virus (ToYMoV) in Costa Rica

The impact of whitefly-transmitted begomoviruses ( Geminiviridae) on tomato yields depends on plant age at time of infection, and is greatest during the first 5 weeks after germination (critical period). A preventative strategy designed to minimize contact between the vector and the tomato plant by masking the crop with living ground covers during the critical period was promoted among small-scale Costa Rican farmers. A large-scale field experiment replicated over time and location was conducted to evaluate this strategy by assessing the effect of different living ground covers in comparison to the conventional control methods (insecticide or reflective mulch). Living covers including perennial peanuts ( Arachis pintoi, Fabaceae), “cinquillo” ( Drymaria cordata, Caryophyllaceae) and coriander ( Coriandrum sativum, Umbelliferae) reduced the number of incoming whitefly adults, delayed the onset of tomato yellow mottle virus (ToYMoV), and decreased disease severity, resulting in higher yields and profits, compared to the bare soil control. Coriander provided additional economic returns when sold and was easier to establish and remove than the other living covers. Whitefly and begomovirus management with ground covers or reflective polyethylene mulch compared favorably with the conventional insecticide treatment using imidacloprid Therefore, living ground covers appeared to offer a viable and economic management alternative for resource-poor farmers.

Evaluation of extended‐season mating disruption of the Oriental fruit moth Grapholita molesta (Busck) (Lep., Tortricidae) in apples

Abstract: Oriental fruit moth Grapholita molesta (Busck) (Lep., Tortricidae) has recently become a key pest of apples throughout the eastern USA. Pheromone‐mediated mating disruption of Oriental fruit moth was successfully used in North Carolina apple orchards in the past few years. However, low levels of late‐season fruit damage occurred in some orchards treated in late May with hand‐applied pheromone dispensers because of inadequate dispenser longevity. To investigate alternative pheromone application schedules for extended mating disruption control, the following pheromone treatments were compared with conventional insecticides in Henderson County (NC) in 2002: late May application of hand‐applied dispensers; late June application of hand‐applied dispensers; late May application of hand‐applied dispensers supplemented with a late August application of sprayable pheromone dispensers; late May application of hand‐applied dispensers which have a longer activity period; and conventional insecticides as a control. All treatments were sprayed with an insecticide at petal fall in late April for thinning and for control of the first generation Oriental fruit moth adults. Pheromone trap catches were significantly reduced in all mating disruption blocks compared with conventional insecticide blocks. Among pheromone treatments, the highest trap captures were recorded in the delayed hand‐applied dispenser treatment in June before treatment. However, the mean percentage fruit damage did not vary with timing of application of hand‐applied dispensers and the type of pheromone dispenser used. Clearly, the combination of each mating disruption treatment with insecticide application against first generation Oriental fruit moth was as effective as the conventional insecticide treatment under moderate population pressure.

Control of the European grapevine mothLobesia botrana in Greece by the mating disruption technique: A three-year survey

During 1996–1998 mating disruption trials were conducted on all three generations of the grapevine mothLobesia botrana Den. et Schiff. (Lep., Tortricidae) in a 25-ha vineyard situated at Spata, Attiki, Greece. Shortly before the beginning of the first flight period ampoule-type pheromone dispensers were set up lining a 6.5-ha rectangular plot. Around the dispenser zone a protection belt was created whereBacillus thuringiensis (Bt) and selective insecticides were applied against the second and third generation larvae. The protection belt was 35 m wide and covered 3.5 ha. The rest of the vineyard was divided into the reference plot — where conventional insecticide treatments were implemented to control both carpophagous pest generations, and the untreated control plot — which measured 1 ha. Male catches within the dispenser zone were virtually zero. Nevertheless, no difference was apparent between the percentage of mated females from within and outside of the dispenser zone. Attractant was released from the dispensers throughout the season at a rather constant rate, but by the middle of the third flight period dispensers were found to be almost empty. During the 3 years of the survey pest pressure was often at exceptionally high levels. The effectiveness of the mating disruption technique (MDT) was found to vary with year and pest generation. MDT was used against the first (anthophagous) generation with rather poor results. In the following carpophagous generations results were comparable to control measures with insecticides used and sometimes slightly better. The density of the pest population in the pheromone-treated vineyard as compared with the untreated control, was reduced on average by 67% in the second and by 57% in the third generation. MDT therefore did not accomplish sufficient crop protection.

Evaluation of the Fermentation Byproduct Spinosad and Conventional Insecticide Treatments for Controlling Sunflower Beetle Larvae, 1996

Abstract A commercial sunflower field near Mina, in north-central South Dakota, was selected foi our trial of several insecticide treatments at standard and reduced rates for management of SB larvae. The experiment was arranged in a RCBD with 4 replications, and individual treatment plots were 25 ft long by 10 rows (38 inch spacing) wide. In addition, each plot was bordered by two buffer rows to prevent drift. Pre-application evaluations were carried out using whole-plant visual counts of the number of live SB larvae per plant. Twenty plants were examined from each treatment plot and these counts indicated an average of 11 SB larvae per plant within the test area. Treatments were applied on 11 Ju’ using a CO2-propelled backpack sprayer system with a hand-held 6.7-ft long boom. The boom was equipped with 4 TeeJet 8001 nozzles spaced 20 inches apart, and was calibrated to deliver a spray volume of 15 gpa while traveling at 3 mph. Insecticide efficacy was evaluated at 6 DAT using the same count ing technique and number of samples described for pre-application sampling. Data were analyzed with SAS’ s General Linear Models procedure and means were compared using DMRT.

Subsurface Applications of Myx-678 and Turcam for Control of Annual White Grubs, 1992

Abstract This study was conducted in Lincoln, NE on a Kentucky bluegrass golf course fairway. The turf (95% Kentucky bluegrass) was maintained at a mowing height of 1.6 cm and thatch accumulation (finger compressed) in the plot area was 1.3 to 1.9 cm. Field conditions at the time of application were: air temperature, 27.2°C; soil temperature (10-cm depth), 16.7°C; soil type, silty clay loam; soil organic matter, 3-5%; soil pH, 6.0 to 7.0; water pH, 7.0; soil moisture, 15%. Plots were 1.05 X 4.5 m and the experimental design was a RCB with 3 replications. Insecticides were applied 18 Aug; subsurface treatments were applied using a Cushman prototype subsurface applicator designed to place liquid insecticides at the soil-thatch interface (average depth, 1.9 cm), and a Cushman prototype high pressure liquid injector. Conventional liquid insecticide treatments were applied with a C02 sprayer. Immediately following applications, plots were irrigated with 1 cm of water. The test area received approximately 3.8 cm of irrigated water during the post-treatment period. Treatments were evaluated 21 DAT on 8 Sep by removing from each plot three, 20.3 cm diam turf-soil cores (.09 m2 total area) to a depth of 7.6 cm and counting the number of surviving grubs

Use of a multi-component pheromone formulation for control of cotton bollworms (Lepidoptera: Gelechiidae and Noctuidae) in Pakistan

AbstractA hand-applied ‘twist-ti’ pheromone formulation containing the combined pheromones of Pectinophora gossypiella (Saunders) (Gelechiidae), Earias vittella (Fabricius) and E. insulana (Boisduval) (Noctuidae) was used in trials conducted in Pakistan from 1986 to 1988. In plots of cotton ranging in area from 2.8 to 6.0 ha, season-long control of the bollworm complex was achieved using the pheromone formulation applied alone or together with one conventional insecticide treatment, with the conventional insecticide spray programme requring up to five applications of insecticide to achieve a similar level of control. No significant differences were found in yield estimates from plots treated with pheromones compared with plots receiving conventional insecticide treatments. Significantly higher levels of boll infestation and lower yield estimates occurred in control plots where neither pheromones nor insecticides were applied.

Predaceous Insects: Effect of Adding Permethrin to the Sticker Used in Gossyplure Applications1

Gossyplure has been widely used in commercial treatments to suppress the pink boll-worm, Pectinophora gossypiella (Saunders). Studies have shown that permethrin, added to the sticker used to adhere fibers containing gossyplure (NoMate Attract ‘n Kill) to the foliage, increased the effectiveness of the treatment. This study was conducted to determine whether the addition posed a significant threat to predaceous insects, and to compare any effect with that of a conventional insecticide treatment. Plots treated with the combination containing the largest amounts of sticker and permethrin, 1/50 the amount of permethrin conventionally applied, continued to harbor the highest densities of predators after treatment. By comparison, a conventionally applied acephate, trichlorfon, and sulfur mixture assayed in a similar manner produced high mortality of the beneficial insect taxa sampled. The data suggest that the mixture of a small quantity of permethrin into the gossyplure-sticker system is not likely to injure populations of predators that control other insects attacking cotton in mid- and late season.

Disruption of Pheromone Communication of the Tobacco Budworm in Tobacco Fields Treated with Pheromone Components12

Two tobacco fields were treated throughout the growing season with a blend of three aldehydes and one alcohol, components of the sex pheromone of the tobacco budworm, Heliothis virescens (F.). Captures of tobacco budworm males in pheromonebaited cone traps were greatly reduced in the pheromone-treated fields compared with the control field under conventional insecticide treatment. Moreover, mating of laboratory-reared females confined on mating tables in the pheromone-treated fields was reduced 88 to 98%. However, it was necessary to spray the pheromone-treated fields to control the tobacco hornworm, Manduca sexta (L.), and green stink bug, Acrosternum hilare (Say). Because these insecticide treatments also killed tobacco budworm larvae, it was impossible to assess the full impact of the pheromone treatment on control of this species. Nevertheless, these results indicate that the air permeation technique will not be adaptable for control of the tobacco budworm in tobacco until similar remedies are available for control of the tobacco hornworm and possibly other pest species.