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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]

Fall armyworm (FAW) Spodoptera frugiperda, is a serious invasive pest of many crops that causes huge economic losses to agricultural commodities. Insecticides are employed for the management of S. frugiperda. In this study, we investigated the impact of sublethal concentration (LC10) and low lethal concentration (LC30) of spinetoram and emamectin benzoate on S. frugiperda using two-sex life table method. Bioassay results revealed that emamectin benzoate exhibited more toxicity on the 3rd instar of S. frugiperda (LC50 8.35 × 10−4 mgL−1) than spinetoram (LC50 2.6 × 10−2 mgL−1) after 48 h exposure. The total longevity, adult pre-ovipositional period (APOP) and total pre-ovipositional period (TPOP) were prolonged, while pre-adult survival rate and fecundity were reduced at both concentrations of spinetoram and emamectin benzoate. Moreover, the key demographic parameters, including the intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (R0), were significantly lower in insecticide treated groups as compared to untreated insects. Our findings revealed that the sublethal and low lethal concentrations of both insecticides reduce the survival and reproductive capability of S. frugiperda. These results would be useful to assess the overall effect of both insecticides on S. frugiperda and can provide important implications for the rational utilization of insecticides against S. frugiperda. [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.) 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]

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]

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]

Insect predators, in general, play an important role in regulating pest populations in agricultural systems, but may be negatively affected by pesticides used in pest management. Convergent lady beetle, Hippodamia convergens Guerin-Meneville (Coleoptera: Coccinellidae) is known as an important biological control agent of soft-bodied insect pests. The development of Integrated Pest Management (IPM) program against insect pests requires an assessment of the side effect of insecticides on biological control agents. In the present work, we assessed the sublethal effects of an insect growth regulator, Pyriproxyfen (juvenile hormone mimic) on a common aphidophagous beetle, H. convergens by computing its demographic parameters through age-stage, two-sex life table theory. Present results showed that sublethal (LC10 and LC30) concentrations of tested insecticide prolonged the pre-adult developmental duration while adult longevity, fecundity and fertility were reduced following treatment compared with control. However, total pre-ovipositional period (TPOP) was declined with the increasing trend of insecticide concentration. In additions, population growth parameters such as intrinsic rate of increase r, finite rate of increase λ and net reproductive rate R0 were dramatically reduced in H. convergens population when they treated with sublethal concentrations pyriproxyfen. Therefore, the results obtained through this study reflected that pyriproxyfen impairs the population growth parameters and could reduce the biological services provided by H. convergens. Thus, more attention should be paid to the use of this insecticide in IPM program. [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]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [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]

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]