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The mechanical properties of a defect-free laser melting (PBF-LB) deposit of an AISI 316L steel alloy were assessed by means of an instrumented indentation test (IIT), at both the macro- and nano-scales. The inherent non-equilibrium microstructure of the alloy was chemically homogenous and consisted of equiaxed grains and large-elongated grains (under the optical microscope) with irregular outlines composed of a much finer internal cell structure (under the scanning electron microscope). Berkovich and Vickers indenters were used to assess the indentation properties across individual grains (nano) and over multiple grains (macro), respectively. The nano-indentation over the X-Y plane revealed nearly constant indentation modulus across an individual grain but variable on average within different grains whose value depended on the relative orientation of the individual grain. The macro-indentation test was conducted to analyze the tensile-like properties of the polycrystalline SS 316L alloy over the X-Y and Y-Z planes. The macro-indentation test provided a reliable estimate of the ultimate tensile strength (UTS-like) of the alloy. Other indentation properties gave inconsistent results, and a post factum analysis was, therefore, conducted, by means of a new approach, to account for the presence of residual stresses. The already existing indentation data were supplemented with new repeated indentation tests to conduct a detailed analysis of the relaxation ability of compressive and tensile residual stresses. The developed methodology allows the effect of residual stresses and the reliability of measured macro-indentation properties to be examined as a function of a small group of indentation parameters. [ABSTRACT FROM AUTHOR]

Ablation sand casting is a new technology for casting aluminum alloys which helps to achieve superior cooling trends during the solidification and results in eutectic microstructure, reduced degree of defects, and improved mechanical attributes. To further enhance the functionality, water-soluble binder-based sand molds are used in conjunction with appropriate control over process parameters for specialized applications such as complex and thin-walled impeller manufacturing. In this regard, the influence of key process parameters including binder ratio (BR), sand grain fineness number (AFS number), and pouring temperature (PT) is investigated thoroughly on the mechanical characteristics (ultimate tensile strength and hardness) and dimensional accuracy of the thin-walled impeller. Ablation sand casting revealed exceptionally enhanced mechanical properties and dimensional accuracy as compared to conventional sand casting. The AFS number and binder ratio were most significant for controlling the dimensional accuracy. Multi-response optimization through Grey Relational Analysis reveals the optimal setting PT = 800 ℃, ASF number = 45, BR = 5% for lower dimensional deviation, higher hardness, and ultimate tensile strength through conventional sand casting. While for ablation case, the optimal conditions PT = 850 ℃, ASF number = 40, BR = 9% are attained against desired attributes. The attributes are significantly improved through ablated sand casting, dimensional accuracy 31.6%, hardness 58.9% and ultimate tensile strength 41.82%, and fractography analysis depicted the ductile fracture surface. The current technology is drawing attention of industry because of its potential in producing castings with superior mechanical properties and improved internal integrity. [ABSTRACT FROM AUTHOR]

Aedes albopictus, ever since, its distribution from country to country, has been known to transmit many viruses (like dengue) to human. The vector possesses enormous plasticity in habitat adoptability. The distribution pattern revealed that maximum population was collected from rural areas during rainy season, at temperature 31-40 ºC and RH 41-50 %. The population was collected from clear water having plastic bottom. The small quite places are more productive breeding places having EC (≤ 1000 µS/m), TDS (≤ 500 ppm) and DO (2-5 mg/l). The larval population was mostly established in the areas having exposed shady conditions and have less distance from human habitation. Flora such as spirogyra, grasses and algae, and predators such as damselfly, water bugs and beetles showed affinity with Ae. albopictus population. Stagnant clear water bodies are considered as potential breeding sites for dengue vector. [ABSTRACT FROM AUTHOR]

Bacillus thuringiensis transgenic cotton, is being a vital part of a pest management program, effectively controlling Helicoverpa armigera. However, the success of Bt technology depends on the persistent susceptibility of target pests to the Bt cotton. In this respect, bioassays were conducted on laboratory reared H. armigera population (1st, 2nd, 3rd, 4th and 5th instar) fed with detached plant leaves, square, flowers, bolls. The results exhibited that first and second instars were most susceptible showing highest percent mortality on leaves > square > flower > bolls of dual toxin genotype CEMB 33 followed by single Bt cotton genotypes (FH-118 > FH-Lalazar > MNH-886 > FH-142, respectively). The third instar was moderately susceptible on all detached leaves > square > flower > bolls of different cotton genotypes; maximum mortality was recorded when larvae fed on leaves of CEMB 33 followed by FH-118, FH-Lalazar, MNH-886 and FH-142, but minimum on FH-942 (non-Bt). The fourth and fifth instars were least susceptible to all tested cotton genotypes and maximum pupation, adult emergence and egg lying was observed. The percent mortality consistently decreased on instar wise basis (1st < 2nd < 3rd < 4th < 5th). The percent pupation, adult emergence and fecundity increased gradually and steadily for 4th and 5th instar larval bioassay. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) production is significantly altered by the infestation of sucking insects, particularly aphids. Chemical sprays are not recommended for the management of aphids as wheat grains are consumed soon after crop harvests. Therefore, determining the susceptibility of different wheat genotypes and selecting the most tolerant genotype could significantly lower aphid infestation. This study evaluated the susceptibility of six different wheat genotypes ('Sehar-2006', 'Shafaq-2006', 'Faisalabad-2008', 'Lasani-2008', 'Millat-2011' and 'Punjab-2011') to three aphid species (Rhopalosiphum padi Linnaeus, Schizaphis graminum Rondani, Sitobion avenae Fabricius) at various growth stages. Seed dressing with insecticides and plant extracts were also evaluated for their efficacy to reduce the incidence of these aphid species. Afterwards, an economic analysis was performed to compute cost-benefit ratio and assess the economic feasibility for the use of insecticides and plant extracts. Aphids' infestation was recorded from the seedling stage and their population gradually increased as growth progressed towards tillering, stem elongation, heading, dough and ripening stages. The most susceptible growth stage was heading with 21.89 aphids/tiller followed by stem elongation (14.89 aphids/tiller) and dough stage (13.56 aphids/tiller). The genotype 'Punjab-2011' recorded the lower aphid infestation than 'Faisalabad-2008', 'Sehar-2006', 'Lasani-2008' and 'Shafaq-2006'. Rhopalosiphum padi appeared during mid-February, whereas S. graminum and S. avenae appeared during first week of March. Significant differences were recorded for losses in number of grains/spike and 1000-grain weight among tested wheat genotypes. The aphid population had non-significant correlation with yield-related traits. Hicap proved the most effective for the management of aphid species followed by Hombre and Husk among tested seed dressers, while Citrullus colocynthis L. and Moringa oleifera Lam. plant extracts exhibited the highest efficacy among different plant extracts used in the study. Economic analysis depicted that use of Hombre and Hicap resulted in the highest income and benefit cost ratio. Therefore, use of genotype Punjab-2011' and seed dressing with Hombre and Hicap can be successfully used to lower aphid infestation and get higher economic returns for wheat crop. [ABSTRACT FROM AUTHOR]

Oxycarenus hyalinipennis Costa (Lygaeidae: Hemiptera) has attained the status of major insect pest drastically affecting the value and production of the cotton crop. The main objective of the study is to estimate losses caused by O. hyalinipennis (10, 20, 30, 40, 50, 60 pairs release / boll) identified on boll weight, fiber characteristics (mike, staple length, staple strength, lint index and Ginning Out Turn), seed index and seed germination, under semi opened bolls of two Bt genotypes (MNH-886 and MNH-456). The offered O. hyalinipennis density is directly proportional to GOT while inversely proportional to boll weight, seed index, germination, lint index, mike, staple length and staple strength. All morphological parameters revealed highly significant but negative correlation with offered densities of O. hyalinipennis. Linear regression model showed that fiber characteristics affected significantly by O. hyalinipennis. Thus, a long term sustainable IPM strategy must be implemented to curtail this bug population under check. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effects of dry, minimum quantity lubrication (MQL), and nanofluid cutting conditions on surface roughness (Ra) and material removal rate (MRR) for Al6082-T6. Three controllable factors, namely, feed rate (Fr), spindle speed (Vs), and depth of cut (Dc) are studied at three levels using Taguchi method. Single-response optimization is conducted using S/N ratio and contour plots. Empirical models of Ra and MRR for all cutting conditions are developed, and analysis of variance (ANOVA) is used to measure the adequacy of these models. Experimental results reveal that 26~30% improvement in Ra could be observed when experimental setup shifted from dry to MQL, and 13~16% improvement is recorded when further shifted to nanofluid cutting condition. No remarkable effect of cutting conditions (dry, MQL, and nanofluid) is observed on MRR. Additionally, Vs is observed insignificant for MRR in all cutting conditions. The appropriate cutting conditions and optimum values of input variables are proposed to the practitioners for industrial machining and production when contemplating face milling processes. [ABSTRACT FROM AUTHOR]

This paper presents the study to investigate the effects of binder ratio, in-gate length and pouring height on hardness, surface roughness and casting defects of sand casting process. Taguchi methodology with L9 orthogonal array was employed to design the experimentation. Sand casting of six blade impeller using A356 alloy was performed and empirical models for all the above response measures were formulated. Confirmatory tests and analysis of variance results confirmed the accuracy of the model. Binder ratio was found to be the most significant parameter affecting casting surface defects and surface roughness. This was followed by pouring height and in-gate length. [ABSTRACT FROM AUTHOR]

The dusky cotton bug, Oxycarenus spp., has now attained the status of a major pest of cotton crops that affects lint as well as the seed quality of cotton. Surveys were conducted to explore the hibernating sites in the districts Faisalabad, Multan and Bahawalpur. The efficacies of six different plant extracts, i.e. Neem ( Azadirachta indica), Milkweed ( Calotropis procera), Moringa ( Moringa oleifera), Citrus ( Citrus sinensis), Tobacco ( Nicotiana tobacum) and Castor ( Ricinus communis) were tested by using three different concentrations of each plant extract, i.e. 5, 2.5 and 1.5% under laboratory conditions at 25±2°C and 70±5% RH. The data were recorded 24, 48, 72 and 96 hours after treatment application. However, Psidium guajava, Azadirachta indica, Eucalyptus camaldulensis and Mangifera indica were graded as host plants heavily infested by Oxycarenus spp. Results (α≤0.05) indicated that increasing the concentration of extracts also increased the mortality. Nicotiana tobacum and Calotropis procera respectively displayed maximum 72 and 71, 84 and 80, 97 and 89% mortality at all concentrations, i.e. 1.25, 2.50 and 5.00%, after 96 hours of application. Two concentrations (2.5 and 5%) are the most suitable for obtaining significant control of the dusky cotton bug. [ABSTRACT FROM AUTHOR]

Studies were conducted to investigate the performance of eight Bt and five non-Bt cotton genotypes against whitefly and thrips and impact of abiotic factors on the population fluctuation of these sucking pests, at Cotton Research Station, Multan, during 2010 and 2011. The results exhibited that Bt genotypes found more susceptible host for the whitefly and thirps than non-Bt genotypes, during the course of years of study. Among Bt genotypes, maximum and minimum temperature showed significant and positive effect on whitefly population whereas relative humidity exerted negative effect during 2010. During 2011, the effect of all the factors was non significant. On cumulative basis, there was positive correlation between population of whitefly and minimum temperature. But in case of non-Bt, it has negative with maximum temperature whereas relative humidity had a positive effect on whitefly population. Similar trend was observed for thrips population on Bt varieties during both years but on non-Bt varieties only minimum temperature exerted strong positive impact on thrips population. Hierarchical regression models for whitefly and thrips revealed that minimum temperature was the most important factor (Bt and non-Bt varieties). Maximum temperature was the major contributing factor for whitefly fluctuation on Bt varieties during 2010. [ABSTRACT FROM AUTHOR]

Citrus limonoids, nomilin and limonin, were used for larvicidal assay against Aedes albopictus utilizing WHO methodology. LC were 305.83, 176.08, and 136.07 μM for nomilin and 850.09, 600.72, and 407.09 μM for limonin after 24, 48, and 72 h, respectively. LT assays exhibited that Savage citrange oil was the best at all concentrations (400, 500, 600, and 700 ppm) while Fairchild and Cassa grande were the weakest oils at 400 ppm, but at 500, 600, and 700 ppm, Carrizo citrange remained at the bottom with highest LT values. Results exhibited that nomilin was more toxic than limonin and therefore provided a clear indication that limonoids in sample oils influenced the potential of respective oil. Out of the 10 tested citrus seed oils, Savage citrange ( Citrus sinensis) comprised the maximum amount of limonin (2823.59 μg/ml) followed by grapefruit, Sacaton citrumelo, and Jaffa. When this oil (Savage citrange) was evaluated for bioassay against larvae of Ae. albopictus, it reflected complete dominance (LC and LT) as compared to rest of the oils. Although Jaffa ( Citrus paradisi) was found to contain nomilin and limonin, it was found less effective as compared to Savage citrange. The oils from Minneola and Chinese lime did not contain limonin and nomilin, and were therefore weak in terms of LC values. Presence of limonin and nomilin in plant products is therefore a significant indicator of the pest control that needs to be exploited in other plants as well. [ABSTRACT FROM AUTHOR]

Adults and immatures of Aedes mosquito populations were collected at temperatures between 40 and 44°C (summer), while larvae were collected at 0°C (winter). Major mosquito activities were observed from February to mid-December at various collection sites that yielded high populations of Aedes spp. from May to September, and high populations of Culex spp. and Anopheles spp. from March to September. In June to July, mosquito activity was suspended because the relative humidity was high (70%); a result of the monsoon rains. In August, with temperature ranging from 38 to 42°C, the populations of Culex, Anopheles and Aedes began to increase (36.8, 32.1 and 26.3%, respectively). Population estimates (through standard prototype Centers for Disease Control (CDC) and Biogents (BG)-sentinel) and species composition of Aedes in forest habitats indicated a rapid increase in the populations of Ae. albopictus (52.3%), Ae. aegypti (19.1%) and Ae. vittatus (28.5%) following the rainy season in July. Areas positive for Ae. albopictus had identical population levels and distribution ranges of Ae. vittatus, however, there were no Ae. aegypti in Ae. albopictus areas from August to September. The population level, seasonal distribution, habitat and areas of adult activity marked by global positioning system (GPS) coordinates are being used for reference and for species composition data of Anopheles spp. (2), Culex spp. (10) and Aedes spp. (5) in addition to associated temperature, relative humidity and physico-chemical factors of larval habitat. Global meteorological changes have caused an expansion of the active period, leading to the mosquito's possibility of being a vector of disease increasing, resulting in the spread of dengue fever. [ABSTRACT FROM AUTHOR]

Pyriproxyfen is a biorational insecticide from IGR family, used worldwide against several economic pests. To evaluate the risk of pyriproxyfen resistance in dusky cotton bug, Oxycarenus hyalinipennis Costa (Hemiptera: Lygaeidae), a major concern for cotton producers, and to formulate strategies effective to tackle resistance, a field collected population was selected with pyriproxyfen under laboratory conditions using seed-dip method. A resistant strain designated as Pyr-SEL (G 18) was developed after repeatedly selecting O. hyalinipennis with pyriproxyfen over eighteen generations. Thereafter, fitness costs, realized heritability (h 2) and cross-resistance were investigated. As a result of selection, Pyr-SEL (G 18) developed a very high level of resistance (resistance ratio = 464.23-fold) compared with the susceptible strain unselected over twenty generations Un-SEL (G 20). The Pyr-SEL (G 18) conferred strong cross-resistance to bifenthrin (146.59-fold), lambda-cyhalothrin (132.96-fold) and fenoxycarb (91.06-fold), whereas showed moderate cross-resistance to diafenthiuron (28.86-fold) and fipronil (22.73-fold). The h 2 estimate was 0.16 in Pyr-SEL (G 18). The developmental duration of O. hyalinipennis pre-adult prolonged, but traits of λ, r and R 0 reduced in Pyr-SEL (G 18) compared with the Un-SEL (G 20). Also, the population projection obtained lower population size for Pyr-SEL (G 18) than Un-SEL (G 20). Fitness studies revealed that high resistance development to pyriproxyfen lowered the relative fitness of Pyr-SEL (G 18) (R f = 0.38) compared with the Un-SEL (G 20). These findings may be practically valuable in tackling O. hyalinipennis resistance for better pest management. Image 1 • Oxycarenus hyalinipennis was selected with pyriproxyfen for eighteen generations. • The Pyr-SEL (G 18) showed very high cross-resistance to bifenthrin, lambda-cyhalothrin and fenoxycarb. • The realized heritability (h 2) of Pyr-SEL (G 18) was 0.16. • The Pyr-SEL (G 18) had prolonged pre-adult duration, reduced λ, r and R 0 and population projection obtained lower size. • The relative fitness of Pyr-SEL (G 18) was lower (R f = 0.38) than of Un-SEL (G 20). [ABSTRACT FROM AUTHOR]

Global crop productivity is reduced by 20–40% annually due to agricultural pests. Mass trapping with insect sex-pheromones have been the major option for the pest control because of non-negative impact on both natural enemy and environment. In addition to this, we can lure and record a wide variety of insect pests with low concentrations of the insect sex pheromone which is released by female insects. However, the lack of understanding regarding the mechanism of how insect sex pheromone lures and traps work in the field has negatively affected the application of these techniques in countries like China and Pakistan. This lack of understanding hinders growers' ability to accurately comprehend the effectiveness and proper utilization of insect sex pheromone lures in pest management. This review summarizes recent advancements in molecular understanding of insect sex pheromones (their relevant structures and compositions), mass trapping, mating disruption and peptide biosensors, various forms of insect sex pheromone traps with a focus on the integration of artificial intelligence, machine learning, deep learning, and smart trap technologies used in Asia. According to this review, the insect sex pheromone technique is not only well understood but can also be effectively utilized for agricultural pest management. [ABSTRACT FROM AUTHOR]

Sugarcane is one of the major cash crop whose low productivity is due to low nutrients supply and insect pest attacks. The nutrient requirement may be fulfilled by increasing the amount of fertilizer supplements but pest attack is difficult to control through poisonous chemicals due to their harmful effects on plant growth as well as human health. Recently, sugarcane black bug (Cavelarius excavates) was reported to attack sugarcane crop in Pakistan which caused plethora of damages to the crop yield. To control the insect pest, first step is to identify the enemy insect precisely. Therefore, a DNA barcode based study was required for the correct identification of bug species. DNA barcoding is one of the most powerful and sophisticated tools for identifying insects where sequence of mitochondrial gene cytochrome C oxidase I (COI) is used as DNA marker. Sugarcane black bug was sampled and its genomic DNA was subject to PCR for amplification of COI gene. Sanger sequencing of targeted gene was done commercially from Macrogen (South Korea). Sequence analysis revealed that our sequence was first DNA barcode sequence of sugarcane black bug (Cavelarius excavates) in the databases. This study will help us to open more ways to understand and controlling sugarcane black bug. [ABSTRACT FROM AUTHOR]

Field experiment was conducted to collect/sample staphylinid beetles with four different traps (flight intercept trap, Berlese funnel trap, light trap and pit fall trap) and net/hand collection from eleven selected locations of Punjab (Pakistan) in 2013 and 2014. Each locality was sampled for 4 days with an interval of two months. Different abiotic factors were noted and Shannon diversity index was calculated for each locality. A total of 4386 specimens (beetles) were collected. Pit-fall traps were found most conducive and effective in sampling beetles followed by Berlese funnel traps and net/hand collection while light traps showed least efficiency. Maximum value of species richness and abundance was observed during Monsoon season (July-August). Paederus fuscipes was the most common species. The highest value of a-diversity index was observed from Sargodha during both years while in case of Shannon-Wiener index value, Murid Wala was the highest during 2013 and Gutwala during 2014. Changa Manga was the place with highest evenness value. The results of Generalized Linear Mixed Model (GLMM) also indicated that the abundance/number of beetles sampled with different collection methods had significant effects with locality and crop type while insignificant effects with time (years). We conclude that methods of trapping need refinement by installing traps for large duration in all study location keeping all conditions (biotic & abiotic) in view to enhance the efficiency of collection methods and exploration of staphylinid beetles. [ABSTRACT FROM AUTHOR]

Studies were conducted to evaluate the life history parameters and predatory potential of a stigmaeid mite Agistemus buntex Chaudhri against Tetranychus urticae Dufour at three constant temperatures viz., 20, 25 and 30°C. At 25°C, egg, larvae, protonymph, deutonymph and egg to adult stages were completed in 7.36, 3.00 2.44, 2.34 and 15.14 days, respectively for male, and 8.48, 3.98, 3.69, 3.52 and 19.67 days, respectively for the female. The development time was longer at other two temperatures. Daily fecundity, total fecundity and sex ratio was much greater at 25°C compared to 20 and 30°C. The lower development threshold was found to be 6.65 and 8.35°C for A. buntex female and male, respectively. Degree day requirements (DD) for A. buntex were 346.02 DD for female and 250 DD for the male. The intrinsic rate of natural increase (rm) of A. buntex was recorded as 0.11 at 25°C. Finite rate of increase (λ) values for A. buntex were found to be 1.07, 1.12 and 1.11 at 20, 25 and 30°C respectively. From obtained results, it can be concluded that A. buntex can become a strong candidate for biological control of T. urticae in Pakistan and elsewhere along-with other control strategies. The findings will serve as baseline information to better understand the biology of the pest, which can be utilized in an effective management program. [ABSTRACT FROM AUTHOR]

Abstract Bactrocera zonata (Saunders) and Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) are major pests of fruits especially guava, posing a trade barrier of Pakistani fruits in foreign markets. Mass trapping of this pest by suitable selection of traps is necessary for its management by the male annihilation technique (MAT). Experiments were conducted in three different guava-producing districts of Punjab, i.e., Faisalabad, Sargodha, and Toba Tek Singh. Three locations in each district were selected for the experiment, three acres each. Three types of traps were used: the round trap (RT), the jar trap (JT), and the pet bottle trap (PBT), with six traps per acre. Multiple linear regression equations and correlations were computed on the mean population data for all traps in each year. April, May, and June (standard weeks 13-23) were fruit fly peak activity periods in all districts. Temperature exerted a highly significant and positive impact on fruit fly populations. Humidity was not significant, but showed a positive relationship with per unit population fluctuation. Rainfall was also not significant, but showed a negative relationship with per unit population fluctuation. The maximum impact of temperature was 43.5 and 42.8% in Faisalabad, the maximum impact of relative humidity was 26.2 and 22.2% in Sargodha, Faisalabad, and the maximum impact of rainfall was 26.3 and 15.1% in Sargodha. The PBT trap had significant and positive correlations with per unit population fluctuation in all three districts during 2015 and 2016. Pet bottle traps gave the maximum adult catches at all districts with minimum cost 13.30 $/ha in a year, which is suitable for farmer’s community to be used in a prediction model. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) is one of the major staple food and cereal crop in all over the world as well as in Pakistan. Agriculture sector contributes 18.9% to Gross Domestic Product and plays an important role in the economy. There are many biotic and abiotic factors responsible for reduced wheat productivity. Many insect pests are associated with wheat which attack on different stages of crop, cause damage and ultimately results in yield reduction. Wheat crop is attacked by Aphid, Wheat weevil, Wheat midges, Cereal leaf beetle, White grubs, Termites, Grasshopper, Hessian fly, Flea beetles, Armyworm, Wheat stem sawfly, Helicoverpa armigera and Pink Graminous Stem Borer. This review aims to enlist important insect pest fauna of wheat and their damages to wheat crop, so that sustainable pests control measures should be adapted to minimize pest infestation and yield losses in the wheat crop. [ABSTRACT FROM AUTHOR]

Pheromones are innate products, exploited for direct population manipulation in the trapping of precise pest density. They demonstrate feasibility and efficiency against Helicopverpa armigera at five different cotton-based agro-ecological sites: river site, vegetable farm, orchard, clean cultivation site, and forest. The data were recorded at 15–20 day intervals from 8 September 2004 to 1 December 2006. The Number of moths caught during the study period demonstrated that the vegetable farm showed the maximum population of moths per trap (0.54), followed by the orchard (0.29), forest (0.19), river (0.15), and clean cultivation site (0.12). During 2004, rainfall (in the orchard and clean cultivation site) and relative humidity (in the clean cultivation site) showed positive and significant correlation with the number of moths caught. During 2005, temperatures played a significant and positive role in population fluctuation of the pest almost at all the selected sites; the minimum temperature was recorded at the vegetable farm and the average temperature was found at the forest site. Rainfall also showed a significant and positive correlation with trapped moths in the vegetable farm, orchard, and clean cultivation site. During 2006, relative humidity showed a significant and negative correlation with the trapped population at all the sites except the river site. Rainfall showed a negative and significant correlation with the pest at the forest site. Relative humidity was the most important aspect at 8.93% causing variation in the trapped population followed by maximum temperature (5.7%), rainfall (1.63%), average temperature (0.74%), and minimum temperature (0.56%). [ABSTRACT FROM AUTHOR]

The crapemyrtle aphid, Tinocallis kahawaluokalani is a common sap-sucking insect pest of crapemyrtle plant, Lagerstroemia indica L. (Pers.) (Myrtales: Lythraceae). The life history and population characteristics of three aphidophagous ladybird beetles (Coccinella septempunctata, Menochilus sexmaculatus and Oenopia sauzeti) were studied on T. kahawaluokalani based on two sex life table theories. Results reveal that immature survival, total longevity of adult and reproductive parameters was higher for C. septempunctata than to M. sexmaculatus and O. sauzeti. The population dynamic parameters including net reproductive rate (R0), intrinsic rate of increase (r) and finite rate of increase (λ) were higher for C. septempunctata and M. sexmaculatus than those for O. sauzeti. The intrinsic rate of increase 'r' as a key fitness parameter for three aphidophagous predators on T. kahawaluokalani in increasing order was C. septempunctata > M. sexmaculatus > O. sauzeti. These results suggested that C. septempunctata and M. sexmaculatus have more potential to control T. kahawaluokalani. The information obtained from current study may also be useful in using T. kahawaluokalani for mass rearing of these beetles in the laboratory. [ABSTRACT FROM AUTHOR]

Mango (Mangifera indica L.) leaves are susceptible to severe attack by insect gall formers. The study's objective was to assess how different vertical strata of the tree canopy and variation in leaf traits affect gall formation. For this, individual and temporal variation in leaf traits of different mango cultivars (Anwar ratole, Chaunsa, Dusehri, Fajri, Sindri and Siroli) and their ultimate effect on gall formation were studied in 2009-10. In addition, the approximate quantity of carbon, nitrogen, phosphorus, potassium and water content in the leaves was also analysed. Significant variation was found among all mango cultivars for leaf traits and gall formation (p<0.05). Within host individuals, a maximum level of gall formation (200-240 galls, in case of Fajri cultivar) was found on the foliage of the upper tree canopy followed by the lower and inner canopy with the consistent pattern over 2 years. Moreover, gall formation showed significant correlation to carbon to nitrogen (C/N) ratio, phosphorus and potassium level in the leaves of all the studied cultivars except Siroli. [ABSTRACT FROM AUTHOR]

The study was initiated at Entomological Research Institute, Ayub Agricultural Research Institute, Faisalabad, to determine the impact of weather factors in population fluctuation of spotted bollworm Earias sp (E. vittella F and E. insulana B) during 2009 to 2011. On each spot three pheromone traps each ten meters apart were installed in cotton-wheat growing area of Bahawalpur. The data on trapped population of spotted bollworm were recorded fortnightly. The population of the pest remained present throughout the study years. However, the highest peaks were recorded on 10.11.2009 (14.98/trap), on 5.11.2010 (33.22/trap) and on 2.8.2011 (5.60/trap) with maximum, minimum, average temperatures and RH of 32.73°C, 13.00oC, 23.78°C and 66%; 32.47°C, 16.00°C, 24.24°C and 75% and 4.53°C, 26.27°C, 33.40°C and 79.27%, respectively. None of the weather factors showed significant correlation with the pest for individual year and on cumulative basis. Maximum temperature during 2009, relative humidity during 2010, minimum temperature during 2011 and relative humidity on cumulative basis were important resulted in maximum impact i.e. 8.1, 13.9, 15.9 and 7.0 %, respectively in population fluctuation of the pest. [ABSTRACT FROM AUTHOR]

The house fly, Musca domestica, is a serious pest of public health importance with the ability to develop insecticide resistance. The focus of the present study was to evaluate toxicity and resistance of the field collected house flies from Punjab, Pakistan, against insect growth regulator (IGR) insecticides. House flies collected from six different localities exhibited very low levels of resistance to cyromazine, triflumuron, and methoxyfenozide compared with the Lab-susceptible reference strain, with resistance ratios (RRs) ranging between 3.56- to 8.19-fold, 1.45- to 3.68-fold, and 2.20- to 8.60-fold, respectively. However, very low to low levels of resistance were observed for pyriproxyfen and very low to moderate levels for lufenuron with RRs ranged from 4.13- to 11.63-fold to 8.57- to 22.75-fold, respectively. There was a significant correlation between RRs of cyromazine and triflumuron ( r = 0.976, p < 0.001), suggesting the possibility for cross-resistance. Susceptibility status of different IGRs in Pakistani strains of house flies is reported here for the first time. The trend observed in decreasing susceptibility towards different IGR insecticides tested will continue unless resistance management practices are followed. [ABSTRACT FROM AUTHOR]

To evaluate the efficacy of the essential oils extracted from the branches and leaves of eucalyptus (Eucalyptus globules Labill.), neem (Azadirachta indica A. Juss), peppermint (Mentha piperita L.), basil (Ocimum basilicum L.) and from rhizome of ginger (Zingiber officinale Rosc.) against the larvae and pupae of Aedes aegypti L. The essential oils were extracted with Soxhlet apparatus using petroleum ether as a solvent. The oils were evaluated against 1[sup st], 2[sup nd], 3[sup rd], 4[sup th] instar larvae and the pupae of Ae. aegypti following WHO protocol. The dead individuals in all stages were counted after 8, 16, 24 and 48 hours in treatments of different concentrations (100, 200, 300 and 400 ppm). The percent mortality in each stage was determined and consequently LC[sub 50]s were also calculated by Probit analysis. A control treatment was also run by using petroleum ether in which mortality (<6%) of different life stages of Aedes mosquitoes was observed. Results showed that higher mortality was observed in early life stages than later ones. Ginger was more effective having lowest LC[sub 50] after 8 h (142 ppm) and 16 h (8.5 ppm) against 1[sup st] instar larvae followed by peppermint, basil, eucalyptus and neem. However, eucalyptus and peppermint were efficacious after 24 h (66 and 84 ppm) and 48 h (19.5 and 17 ppm), respectively. Ginger oil showed high efficacy in short period of the time (8 and 16 h) followed by peppermint, basil, eucalyptus and neem, whereas eucalyptus oil exhibited its lethality after 24 h, whilst peppermint has longer potency and persistence (48 h) than other plant oils. For pupal stage, peppermint had knockdown effect (8 h) followed by eucalyptus (16 h), basil (24 h) and neem (48 h). From these results, it can be concluded that the oils of E. globules and M. piperita were effective larvicide against the immature stages of Ae. aegypti. © 2015 Friends Science Publishers [ABSTRACT FROM AUTHOR]

To evaluate the efficacy of the essential oils extracted from the branches and leaves of eucalyptus (Eucalyptus globules Labill.), neem (Azadirachta indica A. Juss), peppermint (Mentha piperita L.), basil (Ocimum basilicum L.) and from rhizome of ginger (Zingiber officinale Rosc.) against the larvae and pupae of Aedes aegypti L. The essential oils were extracted with Soxhlet apparatus using petroleum ether as a solvent. The oils were evaluated against 1st, 2nd, 3rd, 4th instar larvae and the pupae of Ae. aegypti following WHO protocol. The dead individuals in all stages were counted after 8, 16, 24 and 48 hours in treatments of different concentrations (100, 200, 300 and 400 ppm). The percent mortality in each stage was determined and consequently LC[sub 50]s were also calculated by Probit analysis. A control treatment was also run by using petroleum ether in which mortality (<6%) of different life stages of Aedes mosquitoes was observed. Results showed that higher mortality was observed in early life stages than later ones. Ginger was more effective having lowest LC[sub 50] after 8 h (142 ppm) and 16 h (8.5 ppm) against 1[sup st] instar larvae followed by peppermint, basil, eucalyptus and neem. However, eucalyptus and peppermint were efficacious after 24 h (66 and 84 ppm) and 48 h (19.5 and 17 ppm), respectively. Ginger oil showed high efficacy in short period of the time (8 and 16 h) followed by peppermint, basil, eucalyptus and neem, whereas eucalyptus oil exhibited its lethality after 24 h, whilst peppermint has longer potency and persistence (48 h) than other plant oils. For pupal stage, peppermint had knockdown effect (8 h) followed by eucalyptus (16 h), basil (24 h) and neem (48 h). From these results, it can be concluded that the oils of E. globules and M. piperita were effective larvicide against the immature stages of Ae. aegypti. © 2015 Friends Science Publishers [ABSTRACT FROM AUTHOR]

The aim of this study was to (1) examine the factors involved in the adoption or non-adoption of Bt cotton, (2) identify sources of Bt cotton seed acquisition, and (3) evaluate farmers' knowledge and perception of insect pests incidence and management practices in Bt cotton in the Punjab, Pakistan. A total of 150 farmers growing Bt cotton expressing Cry1Ac protein were interviewed in the main cotton-growing districts of the Punjab province. The main reasons for farmers adopting Bt cotton were to: (1) reduce bollworm damage; (2) reduce pesticide requirements; (3) obtain higher yield and profit; and (4) reduce labour. Most farmers were not initially aware of Bt cotton's effectiveness against cotton bollworms and then grew it on a trial basis. The main sources of Bt cotton seed were the local market and seed companies while many farmers used home-retained Bt cotton seed, much as they do with conventional cotton. Our survey showed that farmers were aware of the major insect pests of cotton and reported a low incidence of cotton bollworms (Helicoverpa armigera, Pectinophora gossypiella, Earias vitella and E. insulana) and a high incidence of armyworm (Spodoptera litura and S. exigua) and sucking pests (Bemisia tabaci, Thrips tabaci, Amrasca devastans and Aphis gossypii) in Bt cotton. Farmers also noted the incidence of a new pest, the cotton mealybug (Phenacoccus sp.), which caused major damage to the crop in most cotton-growing areas. Farmers knew little about natural enemies and diseases in their fields, but reported a high incidence of cotton leaf curl virus. Farmers still relied heavily on chemicals to control the pests in Bt cotton as they are easily persuaded by the advertisements of pesticide companies. To further understand farmers' perceptions of Bt cotton, a survey of 75 farmers not cultivating Bt cotton was conducted. The main reason for the rejection of Bt cotton by farmers was that they were not sure of its effectiveness against insect pests. Higher prices of Bt cotton seed, perception of higher vulnerability to viral infection and greater requirements for fertilisers and irrigation were also reasons for rejection of Bt cotton cultivation. [ABSTRACT FROM AUTHOR]