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Nicotiana benthamiana, a widely acknowledged laboratory model plant for molecular studies, exhibits lethality to certain insect pests and can serve as a dead‐end trap plant for pest control in the field. However, the underlying mechanism of N. benthamiana's resistance against insects remains unknown. Here, we elucidate that the lethal effect of N. benthamiana on the whitefly Bemisia tabaci arises from the toxic glandular trichome exudates. By comparing the metabolite profiles of trichome exudates, we found that 51 metabolites, including five O‐acyl sugars (O‐AS) with medium‐chain acyl moieties, were highly accumulated in N. benthamiana. Silencing of two O‐AS biosynthesis genes, branched‐chain keto acid dehydrogenase (BCKD) and Isopropyl malate synthase‐C (IPMS‐C), significantly reduced the O‐AS levels in N. benthamiana and its resistance against whiteflies. Additionally, we demonstrated that the higher expression levels of BCKD and IPMS‐C in the trichomes of N. benthamiana contribute to O‐AS synthesis and consequently enhance whitefly resistance. Furthermore, overexpression of NbBCKD and NbIPMS‐C genes in the cultivated tobacco Nicotiana tabacum enhanced its resistance to whiteflies. Our study revealed the metabolic and molecular mechanisms underlying the lethal effect of N. benthamiana on whiteflies and presents a promising avenue for improving whitefly resistance. Summary statement: This work reveals the metabolic and molecular mechanisms underlying the lethal effect of Nicotiana benthamiana on whiteflies and provides a feasible strategy for improving crop resistance against pests. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Protection & Pathology is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Whiteflies (Bemisia tabaci) and the diseases they transmit are a major detriment to crop yields and a significant contributor to world hunger. The highly evolved interactions of host plant, phloem-feeding insect vector with endosymbionts and persistently transmitted virus represent a tremendous challenge for interdisciplinary study. Presented here is the establishment of a colony of axenic whiteflies on tissue-cultured plants. Efficient colony establishment was achieved by a surface sterilization of eggs laid on axenic phototrophically tissue-cultured plants. The transfer of emerging whiteflies through coupled tissue culture vessels to new axenic plants facilitates robust subculturing and produces hundreds of whitefly adults per month. Whitefly proliferation on more than two dozen plant species is shown as well as in vitro testing of whitefly preference for different plants. This novel multi-organism system provides the high-level of biocontainment required by Federal permitting to conduct virus transmission experiments. Axenic whitefly adults were able to acquire and transmit a begomovirus into tissue-cultured plants, indicating that culturable gut microorganisms are not required for virus transmission. The approach described enables a wide range of hypotheses regarding whitefly phytopathology without the expense, facilities, and contamination ambiguity associated with current approaches. [ABSTRACT FROM AUTHOR]

This study investigates the settling preferences and feeding behavior of the Bemisia tabaci whitefly on six cassava cultivars using electrical penetration graph techniques. Six distinct electrical penetration graph waveforms—non-probing, stylet pathway, phloem salivation, phloem ingestion, intracellular puncture, and xylem feeding—were identified and analyzed. Significant differences in the frequency and duration of these waveforms were observed among the cassava cultivars. The whiteflies spent the majority of their time in the non-probing phase, particularly on the Huaybong 80, Kasetsart 50, Rayong 9, and Rayong 72 cultivars. CMR-89 cultivar exhibited higher total probe durations in the phloem salivation and ingestion waveforms, suggesting a greater potential for transmission of the Sri Lankan cassava mosaic virus. The study also examined trichome density and size across the cassava cultivars, revealing that CMR-89 had the highest density and small trichomes, while Huaybong 80 had the lowest density. Trichome characteristics significantly impacted whitefly behavior: larger trichomes were negatively correlated with whitefly settling, whereas higher trichome density was positively correlated with longer settling durations. These findings indicate that trichome-based resistance mechanisms are crucial in whitefly deterrence. Overall, the results suggest that cultivars with lower trichome density and larger trichomes are more resistant to whitefly infestation and subsequent Sri Lankan cassava mosaic virus transmission. These insights are valuable for cassava breeding programs focused on enhancing pest resistance, highlighting the importance of trichome characteristics in developing more resilient cassava varieties. [ABSTRACT FROM AUTHOR]

BACKGROUND: Elucidating fitness cost associated with field‐evolved insect resistance to insecticide is of particular importance to current sustainable pest control. The global pest whitefly Bemisia tabaci has developed resistance to many members of neonicotinoids, but little is known about whitefly resistance to neonicotinoid nitenpyram and its associated fitness cost. Using insecticide bioassay and life‐table approach, this study aims to investigate nitenpyram resistance status in field‐collected whitefly populations, and to explore whether such resistance is accompanied by a fitness cost. RESULTS: The bioassay results revealed that 14 of 29 whitefly populations displayed moderate to extremely high resistance to nitenpyram, demonstrating a widespread field‐evolved resistance to nitenpyram. This field‐evolved resistance in the whitefly has increased gradually over the past 3 years from 2021 to 2023. Further life‐table study showed that two resistant whitefly populations exhibited longer developmental time, shorter lifespans of adult, and lower fecundity compared with the most susceptible population. The relative fitness cost of the two resistant populations was calculated as 0.69 and 0.56 by using net productive rate R0, which suggests that nitenpyram resistance comes with fitness cost in the whitefly, especially on reproduction. CONCLUSION: Overall, these results represent field‐evolved high resistance to nitenpyram in the whitefly. The existing fitness costs associated with nitenpyram resistance are helpful to propose a suitable strategy for sustainable control of whiteflies by rotation or mixture of insecticide with different modes of action. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: The cotton whitefly (Bemisia tabaci) is a major global pest, causing significant crop damage through viral infestation and feeding. Traditional B. tabaci recognition relies on human eyes, which requires a large amount of work and high labor costs. The pests overlapping generations, high reproductive capacity, small size, and migratory behavior present challenges for the real-time monitoring and early warning systems. This study aims to develop an efficient, high-throughput automated system for detection of the cotton whiteflies. In this work, a novel tool for cotton whitefly fast identification and quantification was developed based on deep learning-based model. This approach enhances the effectiveness of B. tabaci control by facilitating earlier detection of its establishment in cotton, thereby allowing for a quicker implementation of management strategies. Results: We compiled a dataset of 1200 annotated images of whiteflies on cotton leaves, augmented using techniques like flipping and rotation. We modified the YOLO v8s model by replacing the C2f module with the Swin-Transformer and introducing a P2 structure in the Head, achieving a precision of 0.87, mAP50 of 0.92, and F1 score of 0.88 through ablation studies. Additionally, we employed SAHI for image preprocessing and integrated the whitefly detection algorithm on a Raspberry Pi, and developed a GUI-based visual interface. Our preliminary analysis revealed a higher density of whiteflies on cotton leaves in the afternoon and the middle-top, middle, and middle-down plant sections. Conclusion: Utilizing the enhanced YOLO v8s deep learning model, we have achieved precise detection and counting of whiteflies, enabling its application on hardware devices like the Raspberry Pi. This approach is highly suitable for research requiring accurate quantification of cotton whiteflies, including phenotypic analyses. Future work will focus on deploying such equipment in large fields to manage whitefly infestations. [ABSTRACT FROM AUTHOR]

The whitefly, Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae), is a global pest of cotton crops. The whitefly causes severe damage to plants both directly and indirectly due to its high dispersal ability, small size, and high reproductive potential. Besides all the possible factors regarding the outbreak of whitefly populations, the major one is widespread use of insecticides, which not only cause resistance development in whiteflies but also cause mortality in beneficial insects. This study reports the extraction, purification, and characterization of insecticidal crude proteins through SDS-PAGE and LC-MS/MS that have insecticidal potential against B. tabaci under lab conditions. This study reports that C. colocynthis fruit extract was the most effective (62%) and (54%) followed by C. colocynthis seed extract (48%) and (36%), respectively, against adult and nymphal instar of whitefly mitotype Asia II-1. Insecticidal crude protein extraction from C. colocynthis fruit was the most effective (77%) and (73%), followed by C. colocynthis seed crude protein (80%) and (76%), respectively, against the adult and nymphal instars of whitefly mitotype Asia II-1. Integration of C. colocynthis fruit crude protein + C. colocynthis seed crude protein was the most effective (82%) and (78%), against the adult and nymphal instars of whitefly mitotype Asia II-1. This study represents the inaugural controlled assessment conducted in Pakistan, providing valuable insights into the application of C. colocynthis insecticidal crude proteins. The findings offer potential alternative techniques for future pest management strategies. [ABSTRACT FROM AUTHOR]

Background: Yellow mosaic disease (YMD) transmitted by white fly, Bemisia tabaci is the most persistent and devastating biotic stress worldwide and in India resulting the reduced productivity of mungbean. At the same time the yield levels in mungbean reached a plateau, which emphasizes the importance of varieties with improved productivity. Methods: In the present investigation, to address this urgent requirement of YMD resistant high yielding varieties, six-parameter model of generation mean analysis was employed for proper understanding of the genetic architecture and gene actions. Susceptible genotype MGG 385 was crossed with four resistant genotypes (LGG 607, LGG 630, WGG 42 and PM 5) to produce respective F1s (during rabi, 2018-19), BC1s, BC2s (during summer, 2019) and F2s (during kharif, 2019). These generations of the four crosses were evaluated for various yield related traits in rabi, 2019-20 and phenotyped for YMD in summer, 2020 at Lam, Guntur, Andhra Pradesh which is hotspot for YMD. Result: The scaling tests and joint scaling test indicated the inadequacy of Additive-dominant model for all most all traits including YMD except for branches per plant and pods per cluster. The study revealed the importance of non-allelic interactions in the inheritance of majority of traits including YMD. Among the non-allelic interactions, [l] type of interaction is predominant. Further, the control of duplicate type of epistasis in the inheritance is evident at least in few crosses for all the traits (except grain yield per plant) that had inadequacy for additive-dominant model, which hinders the pace of the progress through selection. In presence of inter-allelic interaction with such duplicate type of epistasis, population approach in self-pollinated crops, which is similar to recurrent selection in cross pollinated crops or biparental mating followed by conventional selection in the later generations should be adopted for identifying desirable segregants. [ABSTRACT FROM AUTHOR]

Simple Summary: Tomato yellow leaf curl virus (TYLCV) poses a serious constraint to tomato production in the Southeastern United States. Since its introduction, it has become endemic in states such as Georgia and Florida despite tomato-free periods. This study examined whether the endemic status of TYLCV is aided by the Bemisia tabaci B cryptic species' vertical and/or horizontal non-feeding modes of TYLCV (the Georgia variant of the Israel strain) transmission. The potential for 'non-feeding' transmission modes has been examined previously, with inconsistent results. The objective of this study was to determine the frequency of TYLCV transovarial and/or sexual (mating) transmission and the subsequent transmissibility of the virus to virus-free plants. The study utilized a series of virus transmission assays and detection and quantitation tools. Our results indicate that non-feeding transmission modes are a rare phenomenon in this pathosystem, and their significance is irrelevant for the observed endemic status of TYLCV in the southeastern United States. Tomato yellow leaf curl virus (TYLCV) causes significant yield loss in tomato production in the southeastern United States and elsewhere. TYLCV is transmitted by the whitefly Bemisia tabaci cryptic species in a persistent, circulative, and non-propagative manner. Unexpectedly, transovarial and sexual transmission of TYLCV has been reported for one strain from Israel. In this study, the potential contribution of the B. tabaci B cryptic species transovarial and sexual transmission of TYLCV (Israel strain, Georgia variant, Georgia, USA) to reoccurring outbreaks was investigated by conducting whitefly-TYLCV transmission assays and virus DNA detection using end point PCR, DNA quantitation via real-time PCR, and virion detection by immunocapture PCR. TYLCV DNA was detectable in four, two, and two percent of first-generation fourth-instar nymphs, first-generation adults, and second-generation adults, respectively, following transovarial acquisition. Post-mating between viruliferous counterparts, the virus's DNA was detected in four percent of males and undetectable in females. The accumulation of TYLCV DNA in whiteflies from the transovarial and/or sexual experiments was substantially lower (100 to 1000-fold) compared with whitefly adults allowed a 48-hr acquisition-access period on plants infected with TYLCV. Despite the detection of TYLCV DNA in whiteflies from the transovarial and/or mating experiments, the virions were undetectable by immunocapture PCR—a technique specifically designed to detect virions. Furthermore, tomato test plants exposed to whitefly adults that presumably acquired TYLCV transovarially or through mating remained free of detectable TYLCV DNA. Collectively, the extremely low levels of TYLCV DNA and complete absence of virions detected in whiteflies and the inability of the B. tabaci cryptic species B to transmit TYLCV to test tomato plants following transovarial and mating acquisition indicate that neither transovarial nor sexual transmission of TYLCV are probable or epidemiologically relevant for TYLCV persistence in this pathosystem. [ABSTRACT FROM AUTHOR]

Simple Summary: The sweet potato whitefly is a major global pest in vegetable production. The management of this pest has typically relied heavily on insecticide treatments. Many populations of sweet potato whitefly are now resistant to insecticides. Therefore, alternative means to control this pest are needed. Many predatory insects consume sweet potato whiteflies, so helping lure and attract both predators and the pest to the same location could improve control. This study investigates attractive odors for sweet potato whiteflies and two predator species that could be used to improve sweet potato whitefly pest management. Traditionally, olfaction was thought to play a minor role in the behavioral ecology of the sweet potato whitefly, Bemisia tabaci (Gennadius). However, recent research is uncovering significant potential for whitefly management based on olfaction. Incorporating chemical attractants with standard whitefly management programs could significantly improve control. The integration of attractants with biological control is exceptionally promising. Therefore, the behavioral response of B. tabaci and two generalist predators to the green leaf volatiles (E)-2-hexenal, (Z)-3-hexenal, (Z)-3-hexenyl acetate, and (Z)-3-hexe-1-ol were investigated in Y-tube olfactometers. Three of the four green leaf volatiles resulted in the attraction of female B. tabaci. Blend optimization indicated a two-chemical blend to be the most attractive blend for female B. tabaci. In addition, this blend was attractive to female Macrolophus praeclarus (Distant) but did not elicit a behavioral response from either male or female Delphastus catalinae (Horn). The two-chemical blend of green leaf volatiles could be further developed as a lure to attract B. tabaci and its predator, M. praeclarus. [ABSTRACT FROM AUTHOR]

Cotton leaf curl Multan virus (CLCuMuV), a serious viral disease causative agent in cotton plants in South Asia, is transmitted by the Bemisia tabaci cryptic species complex in a persistent circulative manner. A previous study indicated that Asia II-7 whiteflies could transmit CLCuMuV, while Mediterranean (MED) whiteflies failed to transmit CLCuMuV. However, little is known about the genes involved in this process. In this study, Asia II-7 and MED B. tabaci were utilized to determine transcriptomic responses after 48 h of acquisition access periods (AAPs). Result of Illumina sequencing revealed that, 14,213 and 8,986 differentially expressed genes (DEGs) were identified. Furthermore, DEGs related to the immune system and metabolism of Asia II-7 and MED in response to CLCuMuV-infected plants were identified and analyzed using Gene Ontologies (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG), and the number of related DEGs in MED was lower than that of Asia II-7. The most abundant groups of DEGs between both viruliferous and aviruliferous whitefly species were the zf-C2H2 family of transcription factors (TFs). Notably, in comparison to viruliferous MED, Asia II-7 exhibited more DEGs related to cathepsin biosynthesis. Overall, this study provides the basic information for investigating the molecular mechanism of how begomoviruses affect B. tabaci metabolism and immune response either as vector cryptic species or non-vector species. [ABSTRACT FROM AUTHOR]

Bemisia tabaci, commonly known as the sweetpotato whitefly, silverleaf whitefly or tobacco whitefly, is a major global pest of dicotyledonous crops. It causes direct damage through sap feeding and indirectly by transmitting numerous plant viruses. Its high reproductive rate and broad host range contribute to substantial yield losses across multiple crop families, including Fabaceae, Cucurbitaceae, and Solanaceae. Despite extensive research into management strategies, effective and affordable control measures for B. tabaci remain elusive. This review highlights the challenges posed by B. tabaci and emphasizes the urgent need for innovative, integrated pest management strategies to mitigate its impact on global agriculture. [ABSTRACT FROM AUTHOR]

This method of planting is developing in the United States and according to the obtained reports, it has saved water consumption, reduced the cost of weeding, increased production and maturity, and reduced the population of pests and damage to cotton. The advantages of this planting method include increasing maturity as well as crop yield. To investigate this issue in Golestan province, some important studies such as the effect of pix material, different fertilizers, pests and diseases and irrigation in planting very narrow row spacing were evaluated over two years. This experiment is to examine and compare the population of cotton whiteflies on 3 cluster cultivars and one control, using the method of narrow planting distance of 20 × 20 and 20 × 80 cm as a factorial design in the form of an RCBD with 3 replications in Hashemabad cotton research station in Gorgan during two years 2018-2019 was evaluated. Statistics of different stages of cotton whitefly pest were recorded weekly in the tested treatments and recorded in special tables. Based on the studies, the results of the combined analysis of variance showed that the yield in the cultivars tested in the Sajedi cultivar with a distance of 80 cm with an average wash of 1696 gr in the plot and Golestan® cultivar 80 cm with 1622.9 gr in the plot with the highest yield and cultivar T2 with a distance of 20 cm, 847.2 gr had the lowest yield in the plot. Infestation rate of cluster cultivars tested in very narrow cultivation of whitefly population density on Golestan® cultivars with a distance of 80 cm, Sajedi with a distance of 20 cm with 65.50 and 57.75 whitefly in the leaves had the highest infestation, respectively, and on Sajedi cultivars with a distance of 80 cm with a density of 46.75 whitefly on the leaves had the least infestation. [ABSTRACT FROM AUTHOR]

The sweet potato whitefly, Bemisia tabaci MED (Gennadius) (Hemiptera: Aleyrodidae), is highly harmful to solanaceous crops. The use of essential oils (EOs) is promising for the management of several insect pests, promoting both lethal and sublethal effects. This study aimed to evaluate the effects of sublethal concentrations of Pelargonium graveolens L'Her (Geraniaceae) EO on the feeding behavior of B. tabaci MED on tomato plants (Solanum lycopersicum L., Solanaceae). For this research, the electrical penetration graph (EPG) technique was used to monitor whitefly stylet activities on their host plants. Two sets of plants were previously sprayed with two concentrations of EO (the LC25 and LC50, which were determined in a mortality test), a third set was treated with the insecticide cyantraniliprole, and a fourth set received a control treatment. Our results indicate that the insecticide cyantraniliprole and the EO could both reduce the stylet feeding activity of B. tabaci MED, as well as reduce the number and duration of phloem sap ingestion events (waveform E2), which could avoid or reduce the transmission of viruses. Thus, the application of sublethal concentrations of P. graveolens EO, as well as exposure to cyantraniliprole, negatively affected the feeding behavior of B. tabaci MED. This information may contribute to the management of this pest and the reduction of the incidence of viruses in tomato production. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Protection & Pathology is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Whitefly (Bemisia tabaci) is a well known pest of many crops specially vegetables including tomato plant. Mostly tomato plant disorders are directly and indirectly related to the silver leaf whitefly (Bemisia tabaci) feeding. In this manner, most countries use lots of pesticides which are really threatening to the environment and ecosystem at an alarming position. Thus we aim to use different plant extracts to control whitefly efficiently and minimize the negative impact of pesticides on the environment. This experiment was conducted in a greenhouse and field as well to draw complete conclusion. In this experiment we used five different treatments, T1-NLE (neem leaves extracts), T2-TLE (tobacco leaves extracts), T3- combination (TLE+NLE+ neem kernels), T4-insecticide (Movento) and T5-un-treated. According to our findings in the greenhouse, adult whitefly population's lowest count is (0.66±0.248) in NLE treated tomato plants and highest whitefly numbers found were (5.84±1.04) in un-treated plants. For the nymph, the same result follows (0.23±0.20) in NLE treated plants and (5.62±1.20) in un-treated plants. In field's experiment lowest adult population of whitefly found in NLE (1.74±0.48) and highest numbers found in un-treated (9.64±1.23). This experiment proves that plants extracts are more effective, economical and eco-friendly. This study can be potentially extended to other pests and crops. Consolidated viewpoint of this investigation, we state that plants extricates all the more integral assets to control sucking complex or whitefly. [ABSTRACT FROM AUTHOR]

Vegetables are treated as high-value crops due to their sizeable area and production throughout the world but are plagued by a variety of insect pests throughout the growing season. Among vegetables, tomato is most common and extensively grown throughout India and faces the challenge of insect pests. During winter 2021–2022 and 2022-23, tomato crop in Haryana state faced the problem of three important insect pests viz., serpentine leaf miner (Liriomyza trifolii), whiteflies (Bemisia tabaci) and aphids (Aphis gossypii). To monitor and manage these insect pest menace, yellow sticky traps were used under field conditions. The yellow sticky traps were found to be effective in monitoring the target pests for taking up further management interventions wherein the mean number of adult leaf miners, adult whiteflies and alate aphids trapped /square inch of yellow sticky trap ranged from 46.26 ± 1.96 to 61.03 ± 2.59, 5.42 ± 0.12 to 9.68 ± 0.13, and 9.83 ± 0.70 to 15.76 ± 0.34, respectively. Further, it was found that installation of 10–12 yellow sticky traps/0.40 ha proved effective in mass trapping of leaf miners, whiteflies and aphids in tomato by reducing the pest population per plant under field conditions. Integrated approach (Mass trapping using yellow sticky traps + label claim insecticidal spray) recorded less population of serpentine leaf miners (1.70 ± 0.03 live mines/03 leaves), whiteflies (3.91 ± 0.02 adults/03 leaves) and aphids (5.01 ± 0.07/03 young leaves) as compared to conventional approach (Farmer practice). The integrated approach evaluated was found economical resulting in 38.14% less expenditure cost due to 45.45% reduction in insecticidal spray, evincing the economic benefits of integrated approach of pest management over conventional approach in tomato. Therefore, installation of yellow sticky traps at suggested rate are recommended for management of serpentine leaf miners, whiteflies and aphids through mass trapping in tomato crop grown under field condition as an effective component of integrated pest management programme. [ABSTRACT FROM AUTHOR]

Feeding potential and foraging behavior are complimentary to determine the efficiency of a predator. The predatory potential of both grub and adult stages of Cheilomenes sexmaculata (F.) (Coleoptera: Coccinellidae) was investigated against different developmental stages of cotton whitefly, Bemisia tabaci Gennadius (Aleyrodidae: Hemiptera), under laboratory conditions (27 ± 2 °C; 70 ± 5% RH; 14 h L: 10 h D). Fourth instar grub of C. sexmaculata exhibited the highest feeding potential against the whitefly stages (41.74 adults, 33.41 pupae and 31.33 nymphs), whereas first instar grub exhibited the lowest feeding potential (10.15 adults, 9.15 pupae and 7.00 whitefly nymphs). The female beetle consumed the highest number of prey (1445.29 adults, 1364.88 pupae, and 1374.35 whitefly nymphs) followed by male beetle (1390.12 adults, 1308.18 pupae and 1325.35 whitefly nymphs). Both Roger's and Holling's models indicated a type II functional response curve for all the grub and adult stages of C. sexmaculata. Cheilomenes sexmaculata female showed the highest attack rate (4.65 h-1), and the maximum rate of predation 37.5 insects/day, whereas the male beetle recorded the lowest handling time (0.02 h). The fourth instar grub showed the highest attack rate (1.30 h-1) against the B. tabaci pupae, whereas the female beetle showed the maximum rate of predation 38.18 insects/day, with the lowest handling time (0.04 h). Female beetle showed the highest attack rate (6.87 h-1), whereas the fourth instar grub showed the maximum rate of predation 41.7 insects/day with the lowest handling time (0.01 h). Hence, it is advocated to release the fourth instar grubs and adult females of C. sexmaculata collectively for the augmentative biological control of B. tabaci in the IPM program. [ABSTRACT FROM AUTHOR]

Bemisia tabaci Middle East-Asia Minor 1 (MEAM1) is a significant pest that damages a wide range of high-value vegetable crops in south Florida. This pest has demonstrated the ability to develop resistance to various insecticide groups worldwide. Monitoring the resistance levels of MEAM1 populations and maintaining baseline susceptibility data are crucial for the long-term effectiveness of insecticide management strategies. We conducted serial dilution bioassays on 15 field populations of MEAM1 collected in south Florida to assess their resistance to 4 key insecticides: afidopyropen, cyantraniliprole, dinotefuran, and flupyradifurone. To quantify resistance levels, resistance ratios (RR) were generated by comparing the LC50 values of field populations to those of a known susceptible MEAM1 colony reared in the laboratory. Our findings reveal that all field-collected populations were susceptible to dinotefuran (RR 1–8) and flupyradifurone (RR 2–8). While over 80% of the populations tested were susceptible to afidopyropen (RR 1–9), 2 populations exhibited low (RR 38) and moderate resistance (RR 51), respectively. In contrast, most of the populations (57%) showed low to moderate resistance to cyantraniliprole (RR 21–78), and the remaining populations were susceptible (RR 3–10). The 2 populations with resistance to afidopyropen also exhibited moderate resistance to cyantraniliprole. Further research in this direction can aid in refining insecticide resistance management programs in Florida and other regions where B. tabaci MEAM1 is a major pest. Exploring the implications of these findings will be essential for insecticide use and integrated pest management strategies in south Florida. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Protection & Pathology is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Cucumber plants are susceptible to several economically damaging pests, including whiteflies, aphids, thrips and spider mites. This study aimed to evaluate the efficacy of two biological control programs, utilizing different releases of bio-agents, in comparison with chemical control method. The bio-agents used were the aphid parasitoid Aphelinus albipodus Hayat and Fatima (Hymenoptera: Aphelinidae), the green lacewing Chrysoperla carnea (Steph.) (Neuroptera: Chrysopidae) and the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) in two release rates; low and high. Additionally, a chemical pesticides treatment was included for comparison in managing the pests in cucumber greenhouses during the winter seasons of 2022 and 2023, in Egypt. Abundances of whitefly, aphids, thrips and spider mites were recorded weekly throughout the study. Results: The aphid population in the greenhouse with high release rate (BIO 2) showed the highest reduction, with percentages of 84.55 and 89.88% in 2022 and 2023, respectively. Both greenhouse with low release rate (BIO 1) and BIO 2 exhibited significant reductions in the whitefly population, with proportions of 71.31 and 72.01% in 2022, and 82.05 and 85.94% in 2023, respectively. The thrips population also experienced notable reductions in both BIO 1 and BIO 2 greenhouses, with percentages of 72.08 and 75.71% in 2022, and 59.93 and 61.38% in 2023, respectively. However, the pesticide treatment demonstrated the lowest reduction in populations of aphids, whitefly and thrips in both seasons. Nevertheless, in all treatments in the two evaluated seasons, the high release rate of the predatory mite, P. persimilis (15 individuals/m2), proved to be highly effective in maintaining the mite populations below the economic threshold level. However, the population density of the two-spotted spider mite, Tetranychus urticae Koch. (Acari: Tetranychidae), increased in the pesticide-treated greenhouse, indicating the development of resistance to pesticides. Although the tested programs resulted in similar yields, the biological control approach offered the advantage of pesticide-free produce and reduced production costs. Conclusion: For pest management in cucumber growing in greenhouses during winter, it is recommended to use biological control agents at a low release rate at the early occurrence of pests. This approach can help minimize pest populations effectively. [ABSTRACT FROM AUTHOR]

Tobacco whitefly Bemisia tabaci and greenhouse whitefly Trialeurodes vaporariorum, which have a wide host range, are among the most important plant protection problems in agricultural areas all over the world. Within the scope of the study, the infection status of endosymbiont bacteria Wolbachia, Rickettsia and Arsenophonus in the whiteflies was determined by molecular methods. Whiteflies T. vaporariorum and B. tabaci populations were collected from tomato greenhouses at five different locations in Antalya province. This study is the first for endosymbionts of Turkish T. vaporariorum populations. All the three endosymbionts were found in T. vaporariorum and B. tabaci populations. While Arsenophonus was the most frequently found endosymbiont in both whitefly populations, Wolbachia was found in high rates in T. vaporariorum and Rickettsia in B. tabaci. In addition, endosymbiont compositions in individuals belonging to both species were revealed as single, double and triple. Wolbachia (W) and Rickettsia (R) were not found together in any individual of both whitefly species. Out of WR, all single and other multiple endosymbiont combinations were detected in the individuals. However, any infection was not recorded for few individuals from the populations of both species. [ABSTRACT FROM AUTHOR]

Bemisia tabaci New World (NW) (Gennadius) (Hemiptera: Aleyrodidae), a whitefly in the B. tabaci species complex, is polyphagous on many plant species. Yet, it has been displaced, albeit not entirely, by other whitefly species. Potential causes could include issues with adaptation, feeding, and the colonization of new-hosts; however, insights that would help clarify these possibilities are lacking. Here, we sought to address these gaps by performing electropenetrography (EPG) recordings of NW whiteflies, designated "Napus" and "Rapa," reared on 2 colony hosts, Brassica napus and B. rapa , respectively. Analysis of 17 probing and pathway (pw) phase-related EPG variables revealed that the whiteflies exhibited unique probing behaviors on their respective colony hosts, with some deterrence being encountered on B. rapa. Upon switching to B. rapa and B. napus , the probing patterns of Napus and Rapa whiteflies, respectively, adapted quickly to these new-hosts to resemble that of whiteflies feeding on their colony hosts. Results for 3 of the EPG variables suggested that B. rapa 's deterrence against Napus whitefly was significant prior to the phloem phase. This also suggested that adaptation by Rapa whitefly improved its pw probing on B. rapa. Based on analysis of 24 phloem phase-related EPG variables, Napus and Rapa whiteflies performed equally well once they entered phloem phase and exhibited comparable phloem acceptability on both the colony- and new-hosts. These findings demonstrate that NW whiteflies reared on a colony host are highly adaptable to feeding on a new host despite encountering some deterrence during the nonphloem phases in B. rapa plant. [ABSTRACT FROM AUTHOR]

BACKGROUND: Temperature is a primary factor that determines the eco‐geographical distribution and population development of invasive insects. Temperature stress leads to various negative effects, including excess reactive oxygen species (ROS), and catalase (CAT) is a key enzyme against ROS in the antioxidant pathway. The whitefly Bemisia tabaci MED is a typical invasive pest that causes damage worldwide. Our previous studies have shown that CAT promotes whitefly adaptation to high temperature by eliminating ROS. However, the mechanism underlying the low‐temperature adaptation of whiteflies is still unknown. RESULTS: In this study, we investigated the role of CAT in the low‐temperature tolerance of B. tabaci MED by analyzing its survival rate, reproduction, and ROS levels at 25 °C (as a control, suitable temperature), 20 °C (moderately decreased temperature), and 4 °C (severely decreased temperature). Silencing of BtCAT1, BtCAT2, or BtCAT3 reduced the viability of whiteflies under a short‐term severely decreased temperature (4 °C), which manifested as decreases in survival and fecundity accompanied by significant increases in ROS levels. Moreover, even at a moderately decreased temperature (20 °C), silencing of BtCAT1 led to high ROS levels and low survival rates in adults. CONCLUSION: Silencing of BtCATs significantly increased the sensitivity of B. tabaci MED to low temperatures. BtCAT1 is likely more essential than other BtCATs for low‐temperature tolerance in whiteflies. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The whitefly, Bemisia tabaci, is a major pest of cassava in Africa. Developing whitefly-resistant cassava can control both whiteflies and viral diseases. The main aim of this study was to identify cassava genotypes resistant to four B. tabaci populations, sub-Saharan Africa 1—subgroups 1, 2, and 3 (SSA1-SG1, SSA1-SG2, and SSA1-SG3) and sub-Saharan Africa 2 (SSA2) that colonize cassava, as well as understand the mechanisms of resistance. Utilizing the antixenosis and antibiosis techniques in the choice and no-choice tests, respectively, to screen for whitefly resistance, we tested 46 cassava genotypes. Of these, 11 (Njule Red, Nase 3, Nase 1, Kibandameno, Sagonja, Aladu, Kiroba, Magana, 72-TME-14, Sauti, and PER 415) exhibited antixenosis, as they were least preferred for oviposition by all four whiteflies population in choice tests. Ten genotypes exhibited antibiosis (nymph mortality) against SSA1-SG1 and SSA1-SG3 in no-choice tests, and these were, Pwani, Nase 14, Kalawe, Eyope, NGA11, CoI2246, Mkumbozi, KBH2002/0066, Yizaso, and PER 608. Eight genotypes—Tongolo, Mbundumali, Colicanana, Orera, Ofumbachai, Nam 130, Tajirika, and MECU72—exhibited both antixenosis and antibiosis mechanisms against SSA1-SG1 and SSA1-SG3. And these can be considered the best sources of resistance for the potential development of whitefly-resistant cassava varieties in African countries. [ABSTRACT FROM AUTHOR]

The article presents a study which focused on the population dynamics of whitefly (Bemisia tabaci) and jassid (Amrascabiguttula biguttula) affecting black gram (Vigna mungo L.) crops. It was found that whitefly population first appeared during the first week of August 2024, registering a mean population of 0.26 whiteflies per five plants. The infestation showed a positive correlation with morning relative humidity as well as with rainfall.

Whitefly (Bemisia tabaci) population poses significant threat to cotton production in tropical and subtropical countries, and act as a vector for plenty of viruses predominantly begomoviruses and associated satellite molecules. Plant mediated RNAi (PM-RNAi) based approach carrying in silico identified miR166b of Gossypium hirsutum cv. HS6 targeting ESTs (Expressed Sequence Tags) of B. tabaci has been effective against whitefly insect and also providing tolerance from cotton leaf curl disease (CLCuD) as reported earlier. Current study focuses on stability of transgene in subsequent generations of transgenic cotton lines and its effectiveness in providing protection against CLCuD. Subsequent generations showed reduced diseased symptoms and no phenotypic abnormality from exogenous construct. Overall findings demonstrate effectiveness of RNAi based construct against insect vector whitefly and its stable inheritance across subsequent generations underscore the potential of this approach for sustainable protection. [ABSTRACT FROM AUTHOR]

Field studies were carried out to assess the incidence and management of whitefly, Bemisia tabaci (Gennadius) on nine promising potato varieties under sprayed condition and unsprayed condition during 2022-23 and 2023-24 at Chaudhary Charan Singh University, Meerut, U.P., India. The maximum incidence of whitefly (15.32/10 plants) was recorded in Kufri Lima followed by Kufri Lohit (14.57/10 plants), when crop remained unsprayed condition. In protected potato varieties viz., Kufri Kiran, Kufri Chipsona-1, Kufri Anand, Kufri Chipsona-3, Kufri Lohit, Kufri Khyati, Kufri Mohan, Kufri Bahar and Kufri Lima, the population of whitefly was low as compared to unsprayed condition. Potato varieties viz., Kufri Khyati, Kufri Anand and Kufri Mohan recorded the highest mean tuber yield of 43.51, 42.38, and 41.04 t/ha, respectively under sprayed condition. Similarly these varieties recorded maximum yield even under unsprayed condition. Thus, it is concluded from the present study that for effective management of whitefly, potato crop should be well protected by seed treatment with Imidacloprid followed by first spray of pymetrozine 50WG @ 0.06% (6 g/10 l), second spray of thiamethoxam 25 WG @ 0.05% (5 ml/10 l) and third spray of imidacloprid 17.8 SL @ 0.03% (3 ml/10 l) as and when there will be any buildup of whitefly on potato, especially for seed crop to get maximum potential yield. [ABSTRACT FROM AUTHOR]

The sweetpotato whitefly, Bemisia tabaci MEAM1, is one of the most devastating pests of row-crop vegetables worldwide, damaging crops directly through feeding and indirectly through the transmission of many different viruses, including the geminivirus Tomato yellow leaf curl virus (TYLCV). Y-tube olfactometer tests were conducted at different stages of TYLCV infection in tomatoes to understand how TYLCV affects B. tabaci behavior. We also recorded changes in tomato hosts' color and volatile profiles using color spectrophotometry and gas chromatography-mass spectrometry (GC-MS). We found that the infection status of B. tabaci and the infection stage of TYLCV influenced host selection, with uninfected whiteflies showing a preference for TYLCV-infected hosts, especially during the late stages of infection. Viruliferous B. tabaci attraction to visual targets significantly differed from non-viruliferous B. tabaci. Late-stage infected hosts had larger surface areas reflecting yellow-green wavelengths and higher emissions of methyl salicylate in their volatile profiles. These findings shed new light on several critical mechanisms involved in the viral manipulation of an insect vector and its economically important host. [ABSTRACT FROM AUTHOR]

The whitefly, Bemisia tabaci (Gennadius), is a polyphagous and major pest of cotton worldwide. Both adults and nymphs of B. tabaci affect the crop by causing direct and indirect damage. A severe whitefly outbreak was experienced during 2015 on cotton in North India and this was followed by a profound infestation during 2022. The present research rigorously examined whether the proliferation in the whitefly population was an outbreak or the result of a multi factor resurgence. During 2015, whitefly counts remained above the economic threshold level (ETL) between 28th and 35th Standard Meteorological Week (SMW). However, during 2022 above ETL population was observed in 27th SMW and it persisted until 36th SMW. The peak incidence of the whitefly was noticed during 31st and 29th SMW in 2015 and 2022, respectively. The early pest build up in 2022 and longer persistence (≥10 weeks) over the cotton season resulted in more damage to cotton crop. Additionally, pest survillence across the zone on the farmers' fields during 2022 revealed 44.4 per cent spots (585 out of 1,317 locations) above ETL while the corresponding locations in 2015 was 57% (620 out of 1,089). Thus, in 2022 infestation was not uniform in the entire zone wherein only few blocks of Punjab, Haryana and Rajasthan states of India experienced severe infestations of the whitefly. This study reports the complex of factors including weather, delayed sowing, use of tank mixtures/ subleathal doses of insecticides, pest resurgence etc. that might have possibly contributed to these upsurges in whitefly on cotton in north India. [ABSTRACT FROM AUTHOR]

Beauveria bassiana (Bal.-Criv.) is an important entomopathogenic fungus being used for the management of various agricultural pests worldwide. However, all strains of B. bassiana may not be effective against whitefly, Bemisia tabaci, or other pests, and strains show diversity in their growth, sporulation, virulence features, and overall bioefficacy. Thus, to select the most effective strain, a comprehensive way needs to be devised. We studied the diversity among the 102 strains of B. bassiana isolated from 19 insect species based on their physiological features, virulence, and molecular phylogeny, to identify promising ones for the management of B. tabaci. Strains showed diversity in mycelial growth, conidial production, and their virulence against B. tabaci nymphs. The highest nymphal mortality (2nd and 3rd instar) was recorded with MTCC-4511 (95.1%), MTCC-6289 (93.8%), and MTCC-4565 (89.9%) at a concentration of 1 × 106 conidia ml−1 under polyhouse conditions. The highest bioefficacy index (BI) was in MTCC-4511 (78.3%), MTCC-4565 (68.2%), and MTCC-4543 (62.1%). MTCC-4511, MTCC-4565, and MTCC-4543 clustered with positive loading of eigenvalues for the first two principal components and the cluster analysis also corresponded well with PCA (principal component analysis) (nymphal mortality and BI). The molecular phylogeny could not draw any distinct relationship between physiological features, the virulence of B. bassiana strains with the host and location. The BI, PCA, and square Euclidean distance cluster were found the most useful tools for selecting potential entomopathogenic strains. The selected strains could be utilized for the management of the B. tabaci nymphal population in the field through the development of effective formulations. Key points: • 102 B. bassiana strains showed diversity in growth and virulence against B. tabaci. • Bioefficacy index, PCA, and SED group are efficient tools for selecting potential strains. • MTCC-4511, 4565, and 4543 chosen as the most virulent strains to kill whitefly nymphs. [ABSTRACT FROM AUTHOR]

Sri Lankan cassava mosaic virus (SLCMV) is a prominent causative agent of cassava mosaic disease in Asia and relies on the whitefly Bemisia tabaci cryptic complex for its transmission. However, the molecular mechanisms involved in SLCMV transmission by B. tabaci have yet to be understood. In this study, we identified an aminopeptidase N‐like protein (BtAPN) in B. tabaci Asia II 1, an efficient vector of SLCMV, which is involved in the SLCMV transmission process. Through the use of glutathione S‐transferase pull‐down assay and LC‐MS/MS analysis, we demonstrated the interaction between BtAPN and the coat protein (CP) of SLCMV. This interaction was further confirmed in vitro, and we observed an induction of BtAPN gene expression following SLCMV infection. By interfering with the function of BtAPN, the quantities of SLCMV were significantly reduced in various parts of B. tabaci Asia II 1, including the whole body, midgut, hemolymph, and primary salivary gland. Furthermore, we discovered that BtAPN is conserved in B. tabaci Middle East‐Asia Minor 1 (MEAM1) and interacts with the CP of tomato yellow leaf curl virus (TYLCV), a begomovirus known to cause severe damage to tomato production. Blocking BtAPN with antibody led to a significant reduction in the quantities of TYLCV in whitefly whole body and organs/tissues. These results demonstrate that BtAPN plays a generic role in interacting with the CP of begomoviruses and positively regulates their acquisition by the whitefly. [ABSTRACT FROM AUTHOR]

Here we investigated the effect of the insect pest whitefly (Bemisia tabaci), cassava mosaic disease (CMD) and cassava brown streak disease (CBSD) on cassava root yield and quality in two cropping seasons 2014–2015 and 2015–2016 on ten cassava varieties in Tanzania. ANOVA (sum of squares or SS) revealed that the time of planting (42.7%) and cassava variety (29.5%) had the largest effect on whitefly population. Not surprisingly, cassava varieties also had the highest effect (SS 39.8 to 70.4%) on both diseases and yield. An increase in whitefly population led to higher disease incidences and severity in 2015–2016 compared to 2014–2015. Some CBSD-resistant and tolerant cassava varieties like Namikonga and Kiroba, respectively, harboured high whitefly populations. The CMD, CBSD and whitefly-susceptible variety, Mreteta, showed highest yield losses of up to 60%, while the resistant variety NDL 2005/1471 had approximately 1% loss. Deployment of varieties resistant to both diseases and whitefly is thus necessary to safeguard cassava production and food security of vulnerable communities in the affected African countries. [ABSTRACT FROM AUTHOR]

Simple Summary: In agriculture, managing pests like the sweetpotato whitefly, Bemisia tabaci MEAM1, which can severely affect the development and yield of vegetable crops, is crucial. This study explored different insecticide rotations to control this pest on tomato plants. We compared standard synthetic insecticide rotations with biopesticide rotations including biochemical and microbial products alone or combined. Our trials, conducted in the spring and fall of 2023, examined how different insecticide rotations impacted the number of whiteflies. The results showed that while traditional synthetic insecticides consistently reduced the whitefly numbers, biopesticides also provided whitefly control to a lower extent. Overall, although a standard synthetic insecticide rotation adopted in Florida to manage B. tabaci MEAM1 was very effective, microbial biopesticides could become an option to reduce the use of synthetic insecticides and potentially mitigate the risk resistance development. These findings offer farmers new options to manage whiteflies effectively while also considering environmental sustainability. In summary, this research contributes to the ongoing efforts in agriculture to balance effective pest control with the need to protect the environment and reduce chemical usage. The sweetpotato whitefly, Bemisia tabaci MEAM1, is a pest known to significantly impact tomato development and yields through direct damage and virus transmission. To manage this pest, the current study compared the effectiveness of various insecticide rotations. Field trials included rotations involving synthetic insecticides, biochemicals, and microbial agents, applied according to their highest labeled concentrations. The results indicated that while standard synthetic insecticides consistently reduced whitefly egg and nymph counts significantly, microbial biopesticide rotations also achieved reductions, although less consistently. This study demonstrated that while traditional chemical treatments remain highly effective, microbial biopesticides containing Beauveria bassiana and Cordyceps javanica present a viable alternative to manage MEAM1 in tomato fields. The data generated in this study provided baseline information for further investigations to determine the potential for optimizing integrated pest management (IPM) and insecticide resistance management (IRM) strategies by incorporating microbial biopesticides in rotations with a variety of modes of action to sustainably manage B. tabaci MEAM1 populations in agricultural settings. [ABSTRACT FROM AUTHOR]

Simple Summary: As an invasive pest, whitefly causes great losses in agricultural production, and resistance increases in whitefly to chemical insecticides are an important problem in plant protection. Our study revealed that imidacloprid stress inhibits the expression of AKH, thereby increasing ROS and the expression levels of the resistance gene CYP6CM1 and upstream regulatory factors in Bemisia tabaci. AKH silencing by RNA interference affected the resistance of whiteflies to imidacloprid. These results provide insight into the resistance mechanism in whitefly. Synthetic insecticides used to control Bemisia tabaci include organophosphorus, pyrethroids, insect growth regulators, nicotinoids, and neonicotinoids. Among these, neonicotinoids have been used continuously, which has led to the emergence of high-level resistance to this class of chemical insecticides in the whitefly, making whitefly management difficult. The adipokinetic hormone gene (AKH) and reactive oxygen species (ROS) play roles in the development of insect resistance. Therefore, the roles of AKH and ROS in imidacloprid resistance in Bemisia tabaci Mediterranean (MED; formerly biotype Q) were evaluated in this study. The expression level of AKH in resistant B. tabaci MED was significantly lower than that in sensitive B. tabaci (MED) (p < 0.05). AKH expression showed a decreasing trend. After AKH silencing by RNAi, we found that ROS levels as well as the expression levels of the resistance gene CYP6CM1 and its upstream regulatory factors CREB, ERK, and P38 increased significantly (p < 0.05); additionally, whitefly resistance to imidacloprid increased and mortality decreased (p < 0.001). These results suggest that AKH regulates the expression of resistance genes via ROS in Bemisia tabaci. [ABSTRACT FROM AUTHOR]

Sweet pepper is a crop that benefits from phytosanitary treatments with low environmental impact, especially the successful control of pests through the introduction of biological control agents in greenhouses. However, predators that naturally occur in these surroundings often enter greenhouses. The precise roles of these natural predators and their interactions with the introduced predatory insects and mites are often unknown. This study investigated the relationships between Nesidiocoris tenuis, which is naturally present, and Amblyseius swirskii and Orius laevigatus, which are two species of generalist predators released for the control of multiple pests. This study was conducted for two years on 13 commercial sweet pepper crops in various types of greenhouses (tunnels and traditional greenhouses) in Sicily. The environmental complexity value (ECV) for each site was estimated based on 18 points detected around the site according to the different habitats that occurred at each coordinate. The results showed that the occurrence of N. tenuis in greenhouses, independently of their typology (tunnel or traditional greenhouse), was mainly promoted by the greater diversification of habitats immediately surrounding the pepper crops (in a circular area with a diameter of 500 mt), with an increase in its density during the crop season. Moreover, N. tenuis–O. laevigatus's co-occurrence in flowers suggested that they were not impacted by each other's presence and that their co-occurrence had a significant effect on pest reduction, although their co-occurrence was density-dependent. As an intraguild predator, N. tenuis competed with O. laevigatus for Frankliniella occidentalis when many predators were present. In addition, N. tenuis also competed with A. swirskii when they both occurred in flowers at a higher density. This study highlights the importance of pepper plant flowers in promoting a higher occurrence of juvenile forms of N. tenuis within flowers. Amblyseius swirskii colonized the plants in 3 weeks, distributing itself almost uniformly over the leaves with a clear control action against not only Bemisia tabaci but also F. occidentalis when present on the flowers. Thus, this concurrent analysis of several commercial pepper sites within the same production area suggests that, even with similar pest control plans, the diverse variability in the presence of natural enemies must be considered when selecting control strategies for pepper crop pests and that N. tenuis, favored by complex surrounding habitats, contributes actively to pest reduction. [ABSTRACT FROM AUTHOR]

Pumpkins are often referred to as the "king of cucurbits" due to their large fruit size. In 2021, we conducted studies on the biology of the whitefly, Bemisia tabaci, under insect-proof screen house conditions, focusing on both healthy and Squash Leaf Curl China Virus (SLCCNV)-infected pumpkin plants. Before reaching adulthood, the whiteflies went through three nymphal instars and a pupal stage. In terms of fecundity, female whiteflies laid between 42 and 57 eggs on healthy pumpkin plants, and between 35 and 49 eggs on SLCCNV-infected plants during the spring season. During the rainy season, fecundity ranged from 45 to 60 eggs per female on healthy plants and 31 to 53 eggs per female on SLCCNV-infected plants. The total life cycle of B. tabaci, from egg to adult, varied between 20 and 26 days on healthy plants and 19 to 27 days on SLCCNV-infected plants during the spring season. In contrast, during the rainy season, the life cycle duration ranged from 18 to 24 days on healthy plants and 18 to 23 days on SLCCNV-infected plants. These findings offer valuable insights into the reproductive and developmental dynamics of B. tabaci in relation to pumpkin plant health and viral infection status. [ABSTRACT FROM AUTHOR]

Bemisia tabaci poses a major threat to tomato crops, causing significant yield losses and economic damage to farmers. This study investigates the conidia filtration method as a potential management strategy for B. tabaci under greenhouse conditions. Evaluating the efficacy of this approach in controlling the whitefly population while potentially promoting plant growth is crucial for developing sustainable solutions for tomato production. Both Trichoderma viride and Beauveria bassiana fungi effectively killed adult whiteflies in this study, significantly exceeding the untreated control. Beauveria bassiana showed slightly higher mortality rates at all time points, achieving a maximum of 69.47% compared to T. viride's 62.22% after 14 days. Trichoderma viride and Beauveria bassiana significantly stimulated plant growth compared to the untreated control. However, T. viride emerged as the superior growth promoter across all assessed parameters: plant height, fresh weight, and dry weight. It achieved the tallest plants (27.31 cm), exceeding both the control and B. bassiana. Similarly, its impact on fresh and dry weight surpassed both the control and B. bassiana, reaching respective values of 14.21 and 2.83 g. These findings suggest that T. viride holds greater potential as a plant growth promoter under the examined conditions. [ABSTRACT FROM AUTHOR]

This study presents the complete genome sequence of a novel nege-like virus identified in whiteflies (Bemisia tabaci MEAM1), provisionally designated as whitefly negevirus 1 (WfNgV1). The virus possesses a single-stranded RNA genome comprising 11,848 nucleotides, organized into four open reading frames (ORFs). These ORFs encode the putative RNA-dependent-RNA-polymerase (RdRp, ORF 1), a glycoprotein (ORF 2), a structural protein with homology to those in the SP24 family, (ORF 3), and a protein of unknown function (ORF 4). Phylogenetic analysis focusing on RdRp and SP24 amino acid sequences revealed a close relationship between WfNgV1 and Bemisia tabaci negevirus 1, a negevirus sequence recently discovered in whiteflies from Israel. Both viruses form a clade sharing a most recent common ancestor with the proposed nelorpivirus and centivirus taxa. The putative glycoprotein from ORF 2 and SP24 (ORF 3) of WfNgV1 exhibit the characteristic topologies previously reported for negevirus counterparts. This marks the first reported negevirus-like sequence from whiteflies in the Americas. [ABSTRACT FROM AUTHOR]

Aleuroclava canangae (Corbett, 1935) was discovered on an ornamental Coleus species in Kerala, India, and represents the first occurrence of this species in India and on this plant host. The species is redescribed and illustrations of the puparium and adult males and females are provided along with morphometric data. A molecular analysis of the species using the COI gene was conducted to characterise it, determine its genetic lineage and compare it to seven other species of Aleuroclava Singh, 1931 and those of other whitefly genera. Results of the DNA analysis indicate that A. canangae forms a clade with Aleuroclava indica (Singh, 1932) which also has two pairs of very elongate, tuberculate setae which appear two-jointed because they have a wider basal part separated from a long slender apical part by a fine suture. The Aleuroclava canangae species group is established and an illustrated key is provided for the 12 species in the group, all of which were once placed in the genus Martiniella Jesudasan and David, 1990, now a synonym of Aleuroclava. The molecular analysis indicates that A. psidii (Singh, 1931), A. guyavae (Takahashi, 1932), A. montanus (Takahashi, 1939) and A. gordoniae (Takahashi, 1932) form a clade within the genus Aleuroclava and share similar morphological characters. Based on the results of the molecular and morphological analyses, Aleurothrixus trachoides (Back, 1912) is transferred back to Aleurotrachelus trachoides (Back, 1912) based on its morphology and the results of the DNA analysis. [ABSTRACT FROM AUTHOR]

Trialeurodes vaporariorum Westwood (greenhouse whitefly) are worldwide polyphagous pests of economic importance that damage solanaceous vegetables. Neonicotinoid pesticides and parasitoid Encarsia formmosa Gahan are the main management strategies applied worldwide, but precise control methods in greenhouse vegetables need to be developed to reduce the application amounts of pesticides and improve the suppression of whitefly populations. Therefore, we assessed the indoor acute toxicities and risk assessment of neonicotinoids for T. vaporariorum and E. formosa adults and pupae and compared the control effects of E. formosa and neonicotinoid acetamiprid. According to the acute toxicities results, most neonicotinoid insecticides were more toxic to E. formosa than T. vaporariorum, and pupae were much less susceptible than adults of both species. Moreover, acetamiprid had a low risk effect on E. formosa. Sole application of E. formosa and acetamiprid could effectively control T. vaporariorum, but their combined application resulted in antagonistic effects on the control of T. vaporariorum. The results showed that a combined application or sole use of E. formosa could reduce the use of insecticides, slow down the development of insecticide resistance in whiteflies, and improve the efficiency of controlling the growth of whitefly populations in greenhouse vegetable production. [ABSTRACT FROM AUTHOR]

The impact of eight pesticides on the transmission of Tomato leaf curl virus (ToLCV) by the whitefly, Bemisia tabaci Gennadius to tomato, Lycopersicon esculentum (Miller), was studied in the field using a randomized block design. Differences in performance were anticipated because these eight insecticides comprise distinct mechanism of action including both contact and systemic. Increased insecticide efficacy is necessary, particularly in regions with conducive weather conditions that support a healthy whitefly population, to effectively manage the population. There is a need to vary the insecticides used in order to reduce the emergence of resistance in the whitefly population due to the extensive usage of a single mechanism of action for whitefly control. The foliar spray of insecticides was done when first incidence of whitefly was noticed in the field with 15 days of interval. The studies on effect of different insecticides in the management of ToLCV disease through the controlling whitefly population, we evaluated that Chlorantraniliprole 8.8% + Thiomethaxam 17.5% SC was effective in sustaining the yield by reducing the incidence of disease and whitefly population during both the years followed by Spirotetramat 11.01% + Imidacloprid 11.01% SC, Thiamethoxam 12.6% + Lambda cyhalothrin 9.5% ZC and Cyantraniliprole 10.26% OD, respectively. [ABSTRACT FROM AUTHOR]

Simple Summary: As whiteflies, Bemisia tabaci (Genn.), are continually developing resistance to conventional insecticides, it is crucial and pressing to seek new approaches to management. In this study, the synergistic effect of lemongrass essential oil and flometoquin, flonicamid, and sulfoxaflor on B. tabaci was studied. Based on the found LC values, the decreasing order of toxicity to B. tabaci was as follows: sulfoxaflor > flonicamid > flometoquin > lemongrass EO. Sulfoxaflor and flonicamid exhibited significant inhibition of AchE activity, while only flonicamid demonstrated a significant impact on α-esterase. However, none of the tested compounds affected cytochrome P450 or GST. Additionally, lemongrass EO and the tested insecticides exhibited significant binding affinity to AchE. The whitefly, Bemisia tabaci (Genn.), is one of the most dangerous polyphagous pests in the world. Eco-friendly compounds and new chemical insecticides have gained recognition for whitefly control. In this study, the toxicity and biochemical impact of flometoquin, flonicamid, and sulfoxaflor, alone or combined with lemongrass essential oil (EO), against B. tabaci was studied. In addition, a molecular docking study was conducted to assess the binding affinity of the tested compounds to AchE. Based on the LC values, the descending order of the toxicity of the tested compounds to B. tabaci adults was as follows: sulfoxaflor > flonicamid > flometoquin > lemongrass EO. The binary mixtures of each of the tested compounds with lemongrass EO exhibited synergism in all combinations, with observed mortalities ranging from 15.09 to 22.94% higher than expected for an additive effect. Sulfoxaflor and flonicamid, alone or in combination with lemongrass EO, significantly inhibited AchE activity while only flonicamid demonstrated a significant impact on α-esterase, and none of the tested compounds affected cytochrome P450 or GST. However, the specific activity of P450 was significantly inhibited by the lemongrass/sulfoxaflor mixture while α-esterase activity was significantly inhibited by the lemongrass/flometoquin mixture. Moreover, the lemongrass EO and all the tested insecticides exhibited significant binding affinity to AchE with energy scores ranging from −4.69 to −7.06 kcal/mol. The current findings provide a foundation for utilizing combinations of essential oils and insecticides in the integrated pest management (IPM) of B. tabaci. [ABSTRACT FROM AUTHOR]

Bemisia tabaci is distributed globally and incurs considerable economic and ecological costs as an agricultural pest and viral vector. The entomopathogenic fungus Metarhizium anisopliae has been known for its insecticidal activity, but its impacts on whiteflies are understudied. We investigated how infection with the semi-persistently transmitted Cucurbit chlorotic yellows virus (CCYV) affects whitefly susceptibility to M. anisopliae exposure. We discovered that viruliferous whiteflies exhibited increased mortality when fungus infection was present compared to non-viruliferous insects. High throughput 16S rRNA sequencing also revealed significant alterations of the whitefly bacterial microbiome diversity and structure due to both CCYV and fungal presence. Specifically, the obligate symbiont Portiera decreased in relative abundance in viruliferous whiteflies exposed to M. anisopliae. Facultative Hamiltonella and Rickettsia symbionts exhibited variability across groups but dominated in fungus-treated non-viruliferous whiteflies. Our results illuminate triangular interplay between pest insects, their pathogens, and symbionts—dynamics which can inform integrated management strategies leveraging biopesticides This work underscores the promise of M. anisopliae for sustainable whitefly control while laying the groundwork for elucidating mechanisms behind microbe-mediated shifts in vector competence. [ABSTRACT FROM AUTHOR]

The efficiency of an autodissemination technique in controlling adult whiteflies, Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae) on tomato, Solunum lycopersicum was investigated with previously identified potent fungal isolates of Metarhizium anisopliae ICIPE 18, ICIPE 62 and ICIPE 69 under screenhouse or semi-field conditions. The autodissemination device was inoculated with dry conidia of the M. anisopliae isolates, while control insects were exposed to a fungus-free device. Sampling for conidia uptake, conidial viability and persistence, and insect mortality was done at 1, 2, 3, 5 and 8 days post-exposure, and collected insects were monitored for mortality over ten days. Overall, mortality was higher in insects exposed to ICIPE 18 (62.8%) and ICIPE 69 (61.8%) than in those exposed to ICIPE 62 (42.6%), with median lethal times, (LT50) ranging between 6.73-8.54 days. The control group recorded the lowest mortality rates (18.9%). A general linear reduction in conidial viability with exposure time was observed, although this was more pronounced with M. anisopliae ICIPE 62. Insects exposed to M. anisopliae ICIPE 69 also recorded the highest conidia uptake, hence selected for further evaluation with a T. vaporariorum attractant volatile organic compound, (E)-2-hexenal. The volatile inhibited fungal germination in laboratory compatibility tests, therefore, spatial separation of M. anisopliae ICIPE 69 and (E)-2-hexenal in the autodissemination device was conducted. The inhibitory effects of the volatile were significantly reduced by spatial separation at a distance of 5 cm between the fungus and the volatile, which was found to be more suitable and chosen for the subsequent experiments. Results showed that (E)-2-hexenal did not influence conidia uptake by the insects, while fungal viability and the subsequent mortality variations were more related to duration of exposure. The fungus-volatile compatibility demonstrated with spatial separation provides a basis for the optimisation of the volatile formulation to achieve better T. vaporariorum suppression with an excellent autodissemination efficiency when used in the management of whiteflies under screenhouse conditions. [ABSTRACT FROM AUTHOR]

Transgenic Bt cotton is effective to a high degree of, with respect to target lepidoptran bollworms, however sucking pests especially whitefly posed a serious issues in absence of bollworm in genetically modified (GM) crops. Therefore, to understand the efficacy of various biorational compounds against whitefly under non-weedy as well as weedy field conditions, studies on whitefly carried out during kharif 2018, to know the changes in number of whitefly adults as well as nymphs. Transgenic hybrid cotton variety RCH 650 was sown with a spacing of 100x45 cm and replicated four times in both non-weedy and weedy habitat. Although, standard check Dimethoate 30 EC proved it's efficacy after first and second spray in cotton crop against whitefly. Not with standing, after the application of biorational first time as spray in 29th Standard Meteoroloical Week (SMW), Nimbecidine 300 ppm was admitted as most effective in non-weedy (66.76 and 60.65% mean mortality in whitefly adult and nymph, respectively) as well as in weedy habitat that caused 56.77 and 55.54% mean mortality in adult and nymph, respectively over a period of seven days after application. Entomopathogenic fungi Verticillium lecanii found better to control whitefly adults (42.06 and 40.63%), while Metarhizium anisopliae (42.39 and 36.01%) found more effective for nymphal mortality in non-weedy as well as in weedy habitat. One and same pattern of efficacy of biorational was reconstructed against whitefly again after second application of biorational in all the treatment selected to test against whitefly. [ABSTRACT FROM AUTHOR]

Plant pathogenic viruses rely on insect vectors for transmission. Among insects, hemipterans, including aphids, leafhoppers, plant hoppers, whiteflies, mealybugs, true bugs, and certain treehoppers, are predominant as vectors for plant viruses. Plant viruses contribute to more than 47% of worldwide plant diseases. Bemisia tabaci is one of the most threatening pests in agriculture, causing significant losses to many important crops on a global scale. Among the most destructive viruses facilitated by whiteflies are begomoviruses (Geminiviridae), forming an emergent and critical group of plant pathogens solely transmitted by the sweet-potato whitefly Bemisia tabaci. In this comprehensive review, we delve into the wealth of data concerning the diverse transmission capacities of various whitefly species, including cryptic members of the B. tabaci complex, in their role as vectors for begomovirus and other viruses. We presented a meticulous analysis of the factors influencing viral transmission by whiteflies, shedding light on the intricate interplay of viruse and their insect vectors. Moreover, this review serves as a crucial reference, presenting a profound exploration of the intricate relationships between whitefly vectors and begomoviruses, and providing valuable insights for the scientific community working towards the sustainable management of plant diseases in the face of evolving challenges posed by these complex biological systems. [ABSTRACT FROM AUTHOR]

The tomato leaf curl viruses (ToLCVs) causing tomato leaf curl disease (ToLCD) in tomatoes is one of the significant constraints for tomato production worldwide and is transmitted by the whitefly, Bemisia tabaci. The ToLCVs, with the emergence of several recombinant variants and B. tabaci with changes in its capability in pathogen transmission, are reported all over the Indian subcontinent. Tomato genotypes resistant to B. tabaci and ToLCV are vital for sustainable control of ToLCD. In the current study, the level of resistance/susceptibility of tomato genotypes to B. tabaci and ToLCV incidence under greenhouse conditions were studied, and promising entries were assessed for antixenosis (non-preference) and antibiosis resistance against B. tabaci. Greenhouse screening by mass release of ToLCV-virulent whiteflies revealed that genotypes EC-520,078 and EC-620,389 (p = < 0.0001) recorded highly resistant reactions for whitefly infestation and ToLCV incidence. The adult settling assay revealed that the genotypes EC-520,078, EC-620,389, EC-315,477, and EC-620,401 (p = < 0.0001) were less preferred by whiteflies. Tests on fecundity, nymphal emergence, nymphal development, and population buildup were conducted to infer the antibiosis effect of the tomato genotypes against B. tabaci. The genotype EC-520,078 (p = < 0.0001) recorded the lowest number of eggs, EC-620,389 (p = < 0.0001) with the lowest nymphal emergence, and EC-520,078, EC-620,389, and EC-620,401 (p = < 0.0001) registered the lowest nymphal development. The F2 generation in the population buildup study was significantly lower in EC-520,078, followed by EC-620,389 and EC-631,364 (p = < 0.0001). The identified resistant sources could be used to develop resistant genotypes against whiteflies and ToLCV in tomatoes. [ABSTRACT FROM AUTHOR]

Simple Summary: Whitefly is one of the most devastating pests of cassava among smallholder farmers in East and Central Africa. The pest causes severe damage to plants through direct feeding as well as spreading the deadly cassava mosaic disease and cassava brown streak disease. Most of the improved cassava varieties in Uganda were developed for cassava mosaic disease resistance and cassava brown streak disease tolerance. Moreover, few research efforts have focused on ascertaining their reaction to whitefly infestation. A research study was therefore conducted to determine the reaction of several improved regional cassava varieties in a bid to identify those with resistance to whitefly in Uganda. The results reveal that cassava variety Mkumba consistently supports low whitefly populations across all locations. The findings of this study further indicate the potential of improved cassava varieties for the effective and sustainable management of whitefly, especially in the high-pest-pressure areas of Uganda and the continent at large. Cassava whitefly, Bemisia tabaci, directly damages cassava leaves by feeding on phloem, causing chlorosis and abscission, leading to a yield loss of up to 50%. The pest also causes indirect damage through sooty mold formation. Most Ugandan cassava varieties resist cassava mosaic disease (CMD) and tolerate cassava brown streak disease (CBSD), but little is known about their response to whitefly infestation. The main objective of this study was to identify cassava genotypes with putative resistance to whitefly in Uganda. This was conducted on 24 improved cassava varieties in three agro-ecological zones during the second rains of 2016. Monthly data were taken for adult and nymph counts, whitefly and sooty mold damage, and CMD and CBSD severities from 2 to 9 months after planting (MAPs). The results show that the whitefly population is highly significantly (p < 0.000) amongst varieties across the three agro-ecological zones. Mkumba consistently supported the low adult numbers and nymphs. The findings demonstrate the potential of the improved cassava varieties as sources of whitefly resistance for sustainable management. [ABSTRACT FROM AUTHOR]

Background: Implementing pest and disease control techniques that have low environmental impact is important for sustainable agriculture. Microbial biopesticides are an effective approach due to their low environmental impact and low risk of resistance development. Because it is not usually possible to control multiple pests and diseases with a single microbial biopesticide, it is essential to investigate the potential for combining microbial biopesticides with varying control spectrums effectively. Many biopesticides have antimicrobial activity and may therefore interact negatively in combination. Results: This study demonstrated that a mixture of Beauveria bassiana and Bacillus subtilis formulations proved potential for simultaneous control of greenhouse whitefly (Trialeurodes vaporariorum Westwood) and tomato powdery mildew (Oidium neolycopersici). Three greenhouse experiments were conducted to assess the efficacy of mixed and single-use treatments. A laboratory experiment comparing the insecticidal effect of each treatment was also conducted. In all greenhouse experiments, the combined treatment controlled the greenhouse whitefly (78.9–88.3%) and tomato powdery mildew (47.2–81.0%) compared to untreated controls, which was as well as each treatment alone. In some greenhouse and laboratory experiments, the mixed treatment showed an approximately 1.32 to 1.78 times higher insecticidal effect compared to single-use treatments. Regarding the control efficacy against the pest and disease, negative effects of microbial agents on each other were not observed. Conclusions: These results demonstrated the effectiveness of concurrent use of two microbial pesticides examined on dual control of pest and disease and showed potential for improved control of certain pests. The knowledge of this work could suggest the possibility of more environmentally friendly pest control systems with the use of microbial pesticides. [ABSTRACT FROM AUTHOR]