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Cold stress has an immediate impact on plant structure and function. A large number of free radicals cause oxidative stress in plants. Cold stress causes altered membrane permeability, lipid peroxidation, and DNA damage. It denatures enzymes and disrupts plant metabolism. Different methods are being investigated for acclimatizing plants subjected to cold stress. Nanobiotechnology and bacterial strains are growing agricultural strategies. Nanoparticles’ (NPs) unique qualities (small size, high mobility, biocompatibility, low cost, and increased reactivity) make them ideal candidates in agriculture. NP and bacterial applications maintain plastid structure and function, enhance antioxidant activities, secondary metabolites, and hormone expression, and reduce electrolyte leakage. They increase the number and content of proteins involved in oxidation–reduction reactions, hormone pathways, stress signaling, and reactive oxygen species detoxification under cold stress conditions. Chitosan, zinc oxide, and titanium dioxide NPs can help plants with cold stress. Meanwhile, bacterial strains in the genus Bacillus and Pseudomonas have been tested for cold tolerance. These strategies also upregulate antifreeze proteins, which are essential for the storage of plant products. Nano-bio-fertilizers should be prepared for the sustainable development of plants under low temperatures.

Residues of the fungicides difenoconazole, propiconazole, cyflufenamid, and mandipropamid were determined in tomato fruit using acetonitrile for extraction and LC-MS/MS for quantification. Validation criteria include linearity range, the limit of detection (LOD) and limit of quantitation (LOQ), accuracy in terms of precision and trueness, and matrix effect were studied. The recovery rates of the method ranged from 91.8 to 106.3%. The precision of the method in terms of repeatability at one day (RSDr) and between three days (RSDR) ranged from 2.8 to 6.4% and from 4.3 to 7.6%, respectively, with good trueness from 92.2 to 96.4%. Matrix effects (suppression effects) ranged from 3.8% to 11.1%. The validated method was used to evaluate the dissipation kinetics of three different premix formulations: 30% EC (15% difenoconazole + 15% propiconazole), 14% DC (12.5% difenoconazole + 1.5% cyflufenamid), and 50% SC (25% difenoconazole + 25% mandipropamid) used on field tomatoes in Egypt. A first-order kinetic equation best describes residue dissipation. The calculated half-lives of difenoconazole, propiconazole, cyflufenamid, and mandipropamid were 2.01–2.27, 1.89, 1.97, and 1.71 days, respectively. The dissipation rate of difenoconazole did not differ significantly in the three premix formulations. Mandipropamid also dissipated faster compared to the other fungicides tested. The chronic dietary risk assessment results showed a minimal risk to adult Egyptian consumers. Waiting periods were advised for the safe consumption of tomatoes treated with the tested premix formulations. [ABSTRACT FROM AUTHOR]

Phytoseius plumifer (Canestrini and Fanzago) and Euseius scutalis (Athias-Henriot) (Phytoseiidae) are generalist predatory mites important in controlling phytophagous mites on some agricultural crops. The biology of both species as potential biological control agents of the grape erineum mite, Colomerus vitis (Pagenstecher) (Eriophyidae) on grape leaf disks was studied in the laboratory at 33 ± 1 °C, 60%RH, 12:12 h L:D. The developmental time, survival, and reproductive parameters of P. plumifer and E. scutalis on C. vitis, date palm pollen as well as C. vitis plus date palm pollen were investigated. Both predators, P. plumifer and E. scutalis, thrived on the mixed diet of C. vitis and date palm pollen resulting in a shorter developmental time (6.16 and 6.69 days, respectively), higher oviposition rate (2.11 and 1.96 eggs/female/day, respectively), and higher intrinsic rate of increase (0.251 and 0.229 per female/day, respectively) than on any other diet. Date palm pollen was an adequate alternative food source for P. plumifer and E. scutalis. The results suggest that both predators have good potential to suppress C. vitis populations and that date palm pollen can support the population establishment of both predators in the absence or scarcity of the main prey in the environment. We discuss the relevance of our results for the biocontrol of C. vitis. [ABSTRACT FROM AUTHOR]

The QuEChERS method was adjusted to determine bifenthrin residues in grapes and grape leaves. Extraction and cleanup procedures were optimized to decrease co-extracted materials and enhance the detection of bifenthrin. The method was validated per the European Union (EU) Guidelines criteria. Accuracy ranged from 98.8% to 93.5% for grapes and grape leaves, respectively. Precision values were 5.5 and 6.4 (RSDr) and 7.4 and 6.7 (RSDR) for grapes and grape leaves, respectively. LOQs (the lowest spiking level) were 2 and 20 µg/kg for grapes and grape leaves, respectively. Linearity as determination coefficient (R2) values were 0.9997 and 0.9964 for grapes and grape leaves, respectively, in a matrix over 1–100 µg/L range of analyte concentration. This was very close to the value in the pure solvent (0.9999), showing the efficiency of the cleanup in removing the co-extracted and co-injected materials; the matrix effect was close to zero in both sample matrices. Dissipation of bifenthrin was studied in a supervised trial conducted in a grapevine field during the summer of 2023 at the recommended dose and double the dose. Dissipation factor k values were 0.1549 and 0.1672 (recommended dose) and 0.235 and 0.208 (double dose) for grapes and grape leaves, respectively. Pre-harvest interval (PHI) was calculated for the Maximum Residue Limit (MRL) values of the EU database. Residues of bifenthrin were removed effectively from grapes using simple washing with tap water in a laboratory study. Residues reached the MRL level of 0.3 mg/kg in both washing treatments, running or soaking in tap water treatments for 5 min. Removal from leaves did not decrease residue levels to the MRL in grape leaves. [ABSTRACT FROM AUTHOR]

A facile procedure for extracting and determining seven neonicotinoids was developed. Water was the only extraction solvent without phase separation and cleanup steps. The method was validated according to European Union standards, and the values obtained were compared with the criteria. The accuracy values were between 99.8% (thiamethoxam) and 106.8% (clothianidin) at the spiking levels of 0.01, 0.1, and 1 mg/kg in the tested matrices. The precision as pooled RSD values was ≤6.1% (intra-day) and ≤6.9% (inter-day). The limit of quantification was set and tested at 0.01 mg/kg. The matrix effect was evaluated, and all matrices had a suppressive effect. The matrix of the cucumber was the most effective, with −20.9% for dinotefuran and an average of −9.8% for all compounds, while the tomato matrix had the slightest effect. Real marketed samples were analyzed using the developed and QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) methods; the results were not significantly different. A supervised field trial was conducted in the open field to study the dissipation patterns of imidacloprid and dinotefuran in tomatoes. The dissipation of both compounds followed first-order kinetics. The half-life (T½) values were 3.4 and 2.5 days, with dissipation rates k of 0.2013 and 0.2781 days, respectively. Following the EU-MRL database, the calculated pre-harvest interval (PHI) values were 7 and 14 days for imidacloprid and dinotefuran, respectively, and 3 days for both compounds following Codex Alimentarius regulations. The risk of imidacloprid and dinotefuran residues was estimated from chronic and acute perspectives. The risk factors of dinotefuran were lower than those of imidacloprid. Nonetheless, the highest expected residues of both compounds were below the tolerance limits. [ABSTRACT FROM AUTHOR]

Tetranychus urticae is an important pest of tomato crops globally, affecting plant yield and growth. Beauveria bassiana and Metarhizium robertsii have the potential to control T. urticae. We investigated the influence of two B. bassiana (i.e., WG-12 and WG-19) isolates and one M. robertsii (WG-02) isolate when colonizing different plant organs (leaves, stems, and roots) and their influence on the growth of tomato plants, through foliar, root-dipping, and seed-soaking application techniques. We also examined the acaricidal activity of the three isolates against T. urticae (female adults), spraying tomato leaf discs with each isolate separately. After 28 days, WG-12 and WG-19 colonized 97 and 91% of the leaves after foliar inoculation, whereas WG-02 exhibited the lowest leaf colonization (76%). The height of the tomato plants, the root length, the number of leaves, and the weight of the biomass above and below the ground were enhanced significantly after inoculation with WG-02 vs. B. bassiana isolates and control. The complete mortality of T. urticae was caused by WG-12 and WG-02 after 10 days, whereas WG-19 killed 94% of the adults. For the effective management of T. urticae, we propose the application of the WG-02 isolate since it provides complete protection and promotes the growth of tomato plants. [ABSTRACT FROM AUTHOR]

Rhizoctonia solani and Fusarium solani were found to have an association with damping-off and complex wilt and root rot symptoms of tomato seedling plants gathered from various greenhouses in Qassim region, Saudi Arabia. The acquired isolates were found virulent enough to attack tomato plants (cv. Tres Cantos) causing complex wilt/rot diseases as well as pre and post emergence of damping-off diseases. These isolates present more virulence in the pathogenicity tests. Huwa-San TR50, a hydrogen peroxide solution that has been stabilized by adding a small amount of silver and has been used extensively as a germicide. Biocide agent Huwa-San TR50 (hydrogen peroxide with 3% silver), was examined for biological control of root wilt/rot and damping-off as well as growth augmentation of tomato plants in vitro and in vivo. The hostile biocide agent hampered growth of the tested morbific fungi and recorded highest inhibited growth in vitro. Under growth chamber condition, all treatments notably decreased root rot/wilt and damping-off intensity and resulted into an increase in the number of surviving plants. Moreover, under growth chamber conditions, these remedies caused an increase in growth parameters (height of plants, and weights when fresh and dry) of the surviving plants which were kept in pots rather than in control conditions. Tomato soil drenching with Huwa-San TR50 in concentration 12000, 14000 and 16000 ppm achieved the ideal results for combating root wilt/rot and damping-off diseases, as well as the highest growth parameters were recorded in growth chamber conditions with the addition of enhanced plant growth and higher yield constituents. [ABSTRACT FROM AUTHOR]

Aims: Skin burns remain a noteworthy general medical issue throughout the world, as it boosts a condition of immunosuppression. The present research aimed to evaluate the efficacy of Syzygium aromaticum extracts, silver sulphadiazine ointment, and different commercially available topical antibiotics against pathogenic bacteria, isolated from the skin of burn patients. Methodology and results: A total of 124 clinical pus samples were collected from the skin of burn patients, admitted to two different tertiary care burn units at Peshawar, Pakistan. From these pus samples, 6 bacterial isolates from burned skin (Staphylococcus epidermidis, Streptococcus, Klebsiella, Enterobacter, Bacillus and Pseudomonas spp.) were isolated, while 4 different bacterial isolates (Staphylococcus epidermidis, Staphylococcus aureus, Bacillus and Streptococcus spp.) were isolated from unburned skin via conventional culturing techniques. Further, antibacterial assays were performed to compare the efficacy of S. aromaticum extracts (methanolic and aqueous extract), silver sulphadiazine ointment, and different commercially available antibiotics against tested bacteria. It was observed that both methanolic and aqueous extracts of S. aromaticum were effective at all concentrations against all the tested bacteria. In addition, all the tested antibiotics expressed substantial activity against most of the bacterial isolates. While silver sulphadiazine ointment was observed to be less potent against isolated bacteria as compared to S. aromaticum extracts. Conclusion, significance and impact of study: It was concluded that both aqueous and methanolic extracts of S. aromaticum were effective antimicrobial agents and could be used as an alternative to control bacterial infections of burn patients. This study would help to distinguish the risk factors of bacterial pathogenicity in burn patients and would also provide a guideline to utilize medicinal plants and their extracts to minimize the chances of antibiotic resistance phenomenon in burn patients. [ABSTRACT FROM AUTHOR]

Tuta absoluta Meyrick (pinworm), is a seriously crucial leaf mining, stalk borers and fruit damaging pest of solanaceae plants. Among solanaceous plants, tomato is considered to be the most preferred host to T. absoluta. Infestations caused by pinworm lead to reduction in tomato yield and its worldwide export. The current study has been conducted to evaluate effectiveness of two entomopathogenic fungi; Beauveria bassiana and Metarhizium anisopliae against eggs of T. absoluta under laboratory conditions. The potential of the two fungi was also assessed as an instrument of integrated pest management system through biological control. Eggs of T. absoluta were treated with four different conidial concentrations of each entomopathogenic fungus. These fungi were evaluated for their toxicity at four different conidial concentrations (4x105, 6x105, 8x105 and 1.0x106 conidia/mL). Twenty-one days post treatment, spore concentration 1.0x106 conidia/mL, resulted in the highest death rate: 50 and 37.6% with eggs when treated by B. bassania and M. anisopliae, respectively. The lowest mortality 33.6 and 25.6% of eggs was observed when T. absoluta eggs were treated with 4x105 conidia/mL of B. bassania and M. anisopliae, respectively. Mortality values resulted from the experiments indicated that B. bassania showed superiority over M. anisopliae regarding its effect on controlling of T. absoluta eggs. In addition, 4x105 conidia/mL showed the minimum mortality effect among the two fungi used in the bioassay. Mortality and spore production on the eggs were significantly higher with the higher spore concentrations (8x105 conidia/mL) of M. anisopliae and B. bassiana. Our findings suggest that the moderate (8x105 conidia/mL) and the higher (10x105 conidia/mL) spore concentration/ml of B. bassania and M. anisopliae are potent entomopathogenic and have the potential to be developed as effective and potent bio-control agents hostile to T. absoluta eggs in IPM programs. [ABSTRACT FROM AUTHOR]

Herein, two‐shaped cerium oxide nanoparticles (NPs), that is, spherical and cubical, were synthesized through hydrothermal approach by tuning reaction temperatures. The morphology and structural and chemical composition of both samples were characterized by transmission electron microscopy (TEM), high‐resolution TEM (HRTEM), X‐ray diffraction (XRD), and X‐ray photoelectron spectroscopy (XPS), respectively. Both types of NPs were subjected to photodegradation of industrial dye, methylene blue, under dark, sunlight, and UV irradiation, and their recyclability and reusability were also assessed. Besides, the effect of pH, concentration of NPs, and dye on degradability was also analyzed. The cubical‐shaped NPs demonstrated superior degradation of ~70% under UV irradiation than the spherical ones (<50%). The antibacterial activities of both NPs were also examined, and cubical‐shaped NPs were found to exhibit superior antimicrobial potential (zone of inhibition [ZOI]: 25.75 ± 0.25, 18.83 ± 0.76, 15.75 ± 0.66, and 15.75 ± 0.25 mm) in comparison with the spherical ones (ZOI: 19.41 ± 0.94, 14.25 ± 0.66, 12.58 ± 1.01, and 9.91 ± 1.01 nm) for Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus respectively with reduced growth and viable count. This difference in performance may be attributed to the higher surface areas of cubical‐shaped NPs and higher content of oxygen vacancies. The results presented in this study suggest that cubical NPs are excellent candidates for treating industrial wastewater with greater reproducibility. Moreover, they can be used as active growth inhibitors against different microorganisms and thus can be extremely useful in developing medical devices and to design various antimicrobial systems. [ABSTRACT FROM AUTHOR]

The toxicity of glyphosate and metribuzin on five species of soil-dwelling predatory mites, Lasioseius dentatus (Fox) (Acari: Ascidae), Androlaelaps casalis (Berlese) (Acari: Laelapidae), Rhodacarus roseus (Oudemans) (Acari: Rhodacaridae), Macrocheles muscaedomesticae (Scopoli) (Acari: Macrochelidae) and Cunaxa setirostris (Hermann) (Acari: Cunaxidae) was evaluated under laboratory conditions. Three different concentrations (half of the recommended dose (HRD), recommended dose (RD) and double the recommended dose (DRD)) of both herbicides were tested. All soil-dwelling predatory mites under study showed high susceptibility to both herbicides, demonstrating that they can significantly reduce the population of all five species of soil-dwelling predatory mites. HRD of glyphosate can reduce the population of all five species of soil-dwelling predatory mites by > 50%, except C. setirostris, as its mortality was 30%, whereas HRD of metribuzin can only reduce the population of L. dentatus and M. muscaedomesticae by > 50%. Obviously, glyphosate seems to be more toxic to all five species of soil-dwelling predatory mites than metribuzin. L. dentatus was found to be the most sensitive soil-dwelling predatory mite, whereas C. setirostris was found to be the least sensitive to both herbicides, as well as a control (well water), compared with all the tested soil-dwelling predatory mites. Finally, the highest mortality rates (100%) were obtained for DRD of both herbicides. Therefore, extra care and serious caution must be exercised when diluting and applying these herbicides to ensure their RD is never exceeded as they can kill all soil-dwelling predatory mites studied here in significant numbers, which leads to a sharp reduction in their populations as well as a reduction in their role in the ecological balance. [ABSTRACT FROM AUTHOR]

The developmental, survival, predation rates, and reproduction of Amblyseius swirskii (Phytoseiidae), as affected by feeding on the motile stages of Phyllocoptruta oleivora (Eriophyidae) and nymphs of Eutetranychus orientalis (Tetranychidae), were studied in the laboratory at six constant temperatures and relative humidities: 9°C and 70% RH; 16°C and 65% RH; 23°C and 60% RH; 30°C and 55% RH, 37°C and 50% RH and 40°C and 45% RH. The maximum daily consumption rate was recorded at 30°C and occurred during the oviposition period, when the females consumed an average of 169.40 specimens of P. oleivora and 24.58 of E. orientalis. The maximum reproduction rate (4.20, and 3.84 eggs/♀/day, on P. oleivora and E. orientalis, respectively) was recorded at 30°C and 50% RH, while the minimum one (1.20 and 0.86 eggs/♀/day, on P. oleivora and E. orientalis, respectively) was observed at 16°C and 65% RH. It is demonstrated in the life-table parameters that when the predatory mite A. swirskii is fed on P. oleivora, the highest reproduction rates (rm = 0.144, 0.195, 0.280, and 0.181 females/female/day) are obtained, while feeding on E. orientalis gave the lowest reproduction rates (rm = 0.121, 0.172, 0.204, and 0.141) at 16°C and 65% RH, 23°C and 60% RH, 30°C and 55% RH, and 37°C and 50% RH, respectively. The results suggest that A. swirskii is a promising control agent for P. oleivora and E. orientalis on orange trees. [ABSTRACT FROM AUTHOR]

Olive is a blessed and therapeutic fruit cultivated all around the globe in relatively temperate and dry regions. Keeping in view the quality and yield of the crop, use of pesticides is indispensable. Traditional pesticides used against crop enemies are effective but unsafe to environment, humans and predators. Olive fields of Saudi Arabia are the biggest in the world and facing infestation due to rapidly increasing number of diverse mite species. Recently, four mite species, Tegelophus hassani, Aceria olive, Oxycenus niloticus and Tetranychus urticae found to be causing severe damage to the plants, have been identified in the olive fields of Saudi Arabia. Huwa-San TR50 is a well-known water disinfectant and considered to be safe as its adverse effects on plants have not been reported as yet. The present study has been conducted to evaluate the use of Huwa-San TR50 as an acricide against four olive mites and two of their predators under laboratory and field conditions. Five different concentrations of Huwa-San TR50; 1000, 2000, 3000, 4000 and 5000 ppm were used based on previous studies to observe mortality of the selected phytophagous mites namely T. hassani, A. olive, O. niloticus and T. urticae. Gradual increase in mortality was observed when mites were treated with Huwa-San TR50 in the concentration range of 1000 - 5000 ppm. Optimum concentration of Huwa-San TR50 to be used against the mites was found to be 4000 ppm as there was negligible increase in mortality beyond this concentration. T. urticae was relatively resistant to Huwa-San TR50 with mortality of 76.58% at optimal concentration. Huwa-San TR50 has effectively impacted egg hatching especially in case of O. niloticus, where successful hatching was only 20%. Eggs of T. urticae are relatively resistant showing 57.97% hatching. The same trend and similar results of mortality and egg hatching were obtained under laboratory and field trials. As an essential part of this research, effect of Huwa-San TR50 was also observed on two predatory mites namely; Phytoseius plumifer and Agistemus exertus and it was found to be relatively safe to predatory mites showing mortality of 30 to 34% at optimum concentration. Again there was insignificant difference in mortality and egg hatching under field and laboratory conditions. Huwa-San TR50 being ecofriendly, safe to predatory mites and an effective acaricide against olive mites and their eggs is recommended for its commercial use in olive orchards. [ABSTRACT FROM AUTHOR]

Traditional acaricides, when used in agricultural fields and green houses, kill predatory mites along with phytophagous mites and cause disturbance in the natural biological control system. The present study involves a novel strategy in pest control systems that is through parallel control on hatching along with killing mites while being at the same time relatively safe to predatory mites. The efficacy of Huwa -San TR50 on the mortality of grape erineum mites, Colomerus vitis, and their egg hatching in comparison to traditional acaricides has been evaluated. Abamectin and bifenthrin cause 83.82 and 98.11% mortality of predatory mites, respectively, when treated with recommended doses. The efficiency of these two acaricides is relatively lower against phytophagous mites, as the highest mortality is 84.46% with bifenthrin and 76.00% with abamectin. It is also observed that abamectin and bifenthrin affect the hatching process negligibly for the eggs of both Colomerus vitis (Pagenstecher) (Acari: Eriophyidae) and Tenuipalpus granati (Sayed) (Acari: Tenuipalpidae). Mortality of C. vitis and T. granati caused by Huwa -San TR50 is 89.86 and 81.76%, respectively, at a spray concentration of 4000ppm. The application of Huwa-San TR50 on eggs of the two phytophagous mites severely affected hatching and only 33.92% successfully hatched. This laboratory study suggests that Huwa -San TR50 can be a better replacement for chemical acaricides. Further, to protect the natural control system through predatory mites, Huwa -San TR50 should be applied as it causes significant mortality in C. vitis and T. granati and is insignificantly harmful to predatory mites. [ABSTRACT FROM AUTHOR]

The predatory phytoseiid mite, Phytoseius plumifer (Canestrini & Fanzago) (Acari: Phytoseiidae), has shown promising traits for biological control of four mite species, Aceria olivi, Oxycenus niloticus, Tegolophus hassani (Acari: Eriophyidae) and Tetranychus urticae (Acari: Tetranychidae), the major pests of olive trees in Saudi Arabia. In the present study, reproduction and population growth parameters of P. plumifer on moving stages of four mite species were studied in the laboratory at 35±1°C, 55±5% RH and a photoperiod of 12: 12 (L: D) hours. The predatory mite, P. plumifer demonstrated that it is capable of developing successfully from egg to adult stage throughout its entire life history consuming only four preys. The total immature developmental time was 5.67, 5.87, 5.92 and 5.77 days for females and 5.18, 5.32, 5.49 and 5.50 days for males when the predator consumed A. olivi, O. niloticus, T. hassani and T. urticae, respectively. The sex ratio of P. plumifer was 0.73, 0.70, 0.70 and 0.60 (females/females + males). Mated females laid on average 2.83, 2.70, 2.38 and 1.72 eggs per day and 57.46, 50.80, 50.02 and 33.95 eggs during their mean ovipositional period of 20.25,18.77, 20.95 and 20.88 days, respectively. The net reproductive rate (R0) was 37.65, 35.18, 33.59 and 26.38 females/female/generation, the intrinsic rate of increase (rm) was 0.298, 0.288, 0.277 and 0.179 females/female/day, the finite rate of increase (λ) was 1.937, 1.861, 1.785 and 1.212 population multiplication/day, and the mean generation time (T) was 14.25, 15.78, 15.22 and 16.56 days when a predator consumed A. olivi, O. niloticus, T. hassani and T. urticae, respectively. The adult predatory female consumed an average of 110.66 A. olivi, 103.71 O. niloticus, 99.75 T. hassani and 14.35 T. urticae/day. These findings imply that the four mites, especially A. olivi, proved to be acceptable nourishment for P. plumifer, as a facultative predator, where P. plumifer does well and is widely and successfully used for biocontrol of A. olivi, O. niloticus, T. hassani and T. urticae associated with olive trees. [ABSTRACT FROM AUTHOR]

The red palm weevil (RPW), Rhynchophorus ferrugineus Olivier, is becoming a real threat to date palm trees in different locations of Saudi Arabia.Therefore, control and management of RPW have gained the attention of government as well as private concerns. In this study, the toxicity of acetamiprid and sulfoxaflor on RPW was evaluated under laboratory conditions. RPW (larvae and adult) showed high susceptibility to both acetamiprid and sulfoxaflor. In addition, both insecticides had significant effect on the mortality of RPW (larvae and adult) except the pupal stage under laboratory conditions. After direct spray application of the recommended dose, the adult mortality percentages were 66.67, 73.33 and 100% for acetamiprid and 23.33, 60 and 96.67% for sulfoxaflor after 1, 24, and 48 h, respectively, whereas the larvae mortality percentages were 63.33, 73.33 and 100% for acetamiprid and 46.67, 73.33 and 96.67% for sulfoxaflor after 1, 24, and 48 h, respectively. Moreover, live RPW (larvae and adult) were found to be completely paralyzed after 24 h of exposure to both insecticides. Statistically, the difference between 1, 24 and 48 h in both adult and larvae at both application (direct spray or soaked palm tissue (contact/ingestion)) was significant (p < 0.05) except the for difference between 1 h and 24 hin larvae with direct spray treatment, which was insignificant (p > 0.05). The study concludes that new information regarding the efficacy of these two insecticides which can be used to replace the conventional, over-aged and less effective insecticides that have been extensively used in controlling RPW. [ABSTRACT FROM AUTHOR]

Injudicious application of insecticides can cause a sharp reduction in the population of several predatory insects and mites including parasitoids. The current study was designed to investigate the effect of four insecticides (i.e. bifenthrin, cypermethrin, deltamethrin and acetamiprid) against the natural population of hymenopterous parasitoids parasitizing various pests of Alfalfa. When used against the pests of Alfalfa, these insecticides also affected the natural population of hymenopterous parasitoids significantly, resulting into ecological imbalance and making the crop more susceptible to pest infestation. This study has proved that bifenthrin, cypermethrin, deltamethrin and acetamiprid can cause a sharp decline of the population of twelve different hymenopterous parasitoids families of (trichogrammatidae, mymaridae, aphelinidae, encytidae, eulophidae, pteromalidae, eupelmidae, ichneumonidae, braconidae, proctotrupidae, platygastridae and scelionidae) with a detectable variation in their resistance to these insecticides. The comparison of means of survival percentage for different insecticides revealed that cypermenthrin caused the lowest mortality (highest survival percentage) to parasitoids followed by deltamenthrin, acetamiprid and bifenthrin to cause maximum mortality respectively (lowest survival percentage) to hymenopterous parasitoids. This would add further environmental concern to the natural population of several predatory insects as their viability will be significantly affected in different contaminative areas. Thus, such studies are also required to investigate the effects of other insecticides which have been extensively used for pest control. [ABSTRACT FROM AUTHOR]

Extensive use of pesticides in public health and agricultural programs has caused many environmental problems as well as toxic effects on non-target organisms including predatory mites. This study has been conducted to determine toxic effects of two acaricides; oxamyl and pyridaben at their three different concentrations. Effect of spray was observed on eggs, immatures and adults of seven predatory mites; Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae), Amblyseius cydnodactylon (Shehata and Zaherand), Phytoseius plumifer (Canestrini and Fanzago), Typhlodromips swirskii (Athias-Henriot), Euseius scutalis (Athias-Henriot), Neoseiulus barkeri (Hughes) (Acari: Phytoseiidae) and Agistemus exsertus (Gonzalez) (Acari: Stigmaeidae) under laboratory conditions. Immature stage of these predatory mites was found to be more susceptible than adults to both oxamyl and pyridaben. The latter was found to be more toxic to immatures and adults than oxamyl. Effect of both pesticides on hatching was found to be insignificant because more than 50% of their eggs were successfully hatched even at the DRD. This study has shown that oxamyl and pyridaben can disrupt biological control due to their toxicity to predatory mites, so extra care must be taken with over application of these acaricides. [ABSTRACT FROM AUTHOR]