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Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is the most devastating pest of tomato crops worldwide. Various biorational management options, such as the application of botanical pesticides, have been deployed to reduce crop damage caused by this invasive pest in Tunisia. In this context, the chemical composition of five plant essential oils (EOs) was explored and their fumigant insecticidal toxicity was evaluated toward larvae of Tuta absoluta and adults of its mirid predator Macrolophus pygmaeus. Gas chromatography coupled with mass spectrometry analysis showed the dominance of monoterpene hydrocarbons and oxygenated monoterpenes in Cymbopogon citratus, Rosmarinus officinalis, Eucalyptus globulus and Salvia officinalis EOs. Ketones are abundant only in Mentha pulegium and S. officinalis EOs. Sesquiterpene hydrocarbons were present in all EOs, while oxygenated sesquiterpenes were found only in C. citratus, R. officinalis and E. globulus. The EOs of C. citratus, R. officinalis, E. globulus, S. officinalis and M. pulegium applied at either 1.25, 2.5, 5, 7.5, 10 or 20 μL/L air at three exposure times (4, 24 and 48 h) were tested against T. absoluta, while the EOs of C. citratus and R. officinalis were assessed on M. pygmaeus. All EOs were toxic toward T. absoluta larvae, causing high mortalities (> 97%) at the highest concentration (20 μL/L air) at 72 h after treatment. Lethal concentration (LC50) values were 20.53, 10.02 and 7.77 μL/L air for C. citratus; 7.53, 5.74 and 5.59 for R. officinalis; 11.09, 5.62 and 5.62 for E. globulus; 11.78, 4.35 and 4.05 for S. officinalis and 10.62, 3.59 and 3.59 for M. pulegium, after 4, 24 and 48 h of exposure, respectively. The highest mortality rates of M. pygmaeus adults exceeded 95% at either 10 or 20 μL/L for either C. citratus or R. officinalis EOs at the three exposure times. These EOs applied at lower concentrations with promising insecticidal potential could be incorporated in integrated pest management programs of T. absoluta, taking into account their possible side effects on M. pygmaeus individuals. [ABSTRACT FROM AUTHOR]

A new pest of tomato, the South American tomato pinworm, Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), was found in Kumamoto Prefecture, Japan in 2021. We examined the genetic variation in the DNA sequences of the mitochondrial cytochrome c oxidase subunit I (mtCOI) gene in 1039 individuals belonging to 39 countries including Japan. In the maximum likelihood phylogenetic tree and haplotype network, 19 haplotypes were detected in the world. Of those haplotypes, only one haplotype (Ta1) was detected from all 39 countries including neighboring countries and Japan. These results and some other information suggest that this species migrated from neighboring countries to Japan. Furthermore, we developed a Multiplex PCR using species-specific primers to discriminate T. absoluta from other gelechiid moth, Phthorimaea operculella (Zeller, 1873) (Lepidoptera: Gelechiidae). We could successfully identify the first instar larvae, fourth instar larvae, pupae, and adults of both species based on the differences in the length of amplicon bands. In addition, we were able to identify adults of both species collected from various prefectures. These results indicated that the Multiplex PCR developed in this study is useful to identify all developmental stages of both species collected in the fields. [ABSTRACT FROM AUTHOR]

Describing the genetic structure and diversity of invasive insect pest populations is essential to better understand a species' invasion history and success throughout its distribution range. Tuta absoluta (Meyrick) (Lepidoptera, Gelechiidae) is a destructive pest of tomato and many other solanaceous crops, with very high economic impacts. Its invasion threatens food security in a large part of the globe, in areas such as sub‐Saharan Africa where the agricultural resilience has already been weakened by rapid human‐induced changes due in particular to population growth, increased trade and global change. This work aimed to investigate the diversity and genetic structure of 60 populations of T. absoluta using microsatellite markers, with a particular focus on sub‐Saharan Africa. Our results revealed distinct differentiation and diversity patterns between T. absoluta native versus invaded areas, and high genetic homogeneity among the African populations sampled. However, for the first time, two weakly differentiated but distinct genetic clusters in Africa were identified. The results suggest few introduction events of the species in Africa or multiple introductions from genetically close areas, significant gene flow between outbreaks and seem to indicate the existence of two distinct clusters in Africa. This new data enable us to formulate hypotheses on the species' invasion patterns and the dynamics of its invasive populations. These hypotheses must be verified with more extensive sampling over the whole range of T. absoluta, especially in its presumed native area. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is one of the most damaging insect pest of tomato worldwide. Tuta absoluta has developed resistance to a wide range of insecticides. Consequently, there is a need to develop alternative control strategies to manage the pest. We evaluated the efficacy of the predatory mirid, Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) alone, as well as in combination with the biopesticide Bacillus thuringiensis (Berliner) against T. absoluta in greenhouse tomato crops under Kuwait hot desert climate. T. absoluta infestation (larval mines/10 leaves/plant) and fruits damaged was significantly lower on treatments based on N. tenuis alone or in combination with B. thuringiensis compared with the control. No significant differences were found in larval infestation, fruit damage, and crop yield between treatments where N. tenuis was released combined with the application of B. thuringiensis compared with treatments where N. tenuis was released alone. Treatments with N. tenuis alone or in combination with B. thuringiensis resulted in 90% and 93% reduction in fruit damage, respectively. Necrotic rings on tomato plants caused by N. tenuis was minimal, and no flower abortion was observed. The potential for including B. thuringiensis and N. tenuis in an overall sustainable management program for T. absoluta is discussed. [ABSTRACT FROM AUTHOR]

This study was carried out to determine the effectiveness of the attract-and-kill (A&K) technique in controlling the South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in open-field tomato growing areas in the Meram district of Konya province (Türkiye) in 2020 and 2021. Three pheromone-treated and three untreated control fields were used in both years. The A&K pheromone (MalEx™) was homogeneously applied by hand to the tomato plant at a dose of 3000 droplets/ha, while no pheromone application was made in the untreated control plots. Delta traps were installed both in untreated control and pheromone-treated plots to monitor T. absoluta populations. The number of males captured in Delta traps and the infestation rates of tomato plants by T. absoluta populations were recorded weekly. In pheromone-treated plots, the mean number of males captured/trap/week in 2020 and 2021 was recorded as 271.06 ± 25.19 and 264.81 ± 23.06, respectively, while it was recorded in untreated control plots as 647.80 ± 58.71 and 668.96 ± 42.02, respectively. The mean infestation rate (%) of T. absoluta in A&K pheromone-treated plots was recorded as 3.83 ± 0.39% and 3.76 ± 0.34%, while it was recorded as 10.18 ± 0.93% and 10.96 ± 0.91% in untreated control plots in 2020 and 2021, respectively. The results of the present study showed that the A&K formulation was successful in the control of T. absoluta in tomatoes grown in open-field conditions of Konya province, Türkiye. [ABSTRACT FROM AUTHOR]

Abstract Phthorimaea absoluta is a global constraint to tomato production and can cause up to 100% yield loss. Farmers heavily rely on synthetic pesticides to manage this pest. However, these pesticides are detrimental to human, animal, and environmental health. Therefore, exploring eco-friendly, sustainable Integrated Pest Management approaches, including biopesticides as potential alternatives, is of paramount importance. In this context, the present study (i) evaluated the efficacy of 10 Bacillus thuringiensis isolates, neem, garlic, and fenugreek; (ii) assessed the interactions between the most potent plant extracts and B. thuringiensis isolates, and (iii) evaluated the gut microbial diversity due to the treatments for the development of novel formulations against P. absoluta. Neem recorded the highest mortality of 93.79 ± 3.12% with an LT50 value of 1.21 ± 0.24 days, Bt HD263 induced 91.3 ± 3.68% mortality with LT50 of 2.63 ± 0.11 days, compared to both Bt 43 and fenugreek that caused

The South American tomato pinworm, Tuta absoluta (Meyrick), is one of the major invasive pests that causes severe economic damage to several hosts, especially tomato plants, globally. Spinosad, a biopesticide widely used against several insect pests, also shows promising results against T. absoluta. Here, we investigated the evolution of spinosad resistance and its effects on biological traits and related gene effects to fully understand the relationship between resistance degree and associated fitness costs. The spinosad-resistant strain (SpRS) with a moderate level of resistance (14.40-fold) was developed following continuous selection of the susceptible strain (SS) against spinosad for eight generations. Fitness analysis showed that the larval and pupal developmental durations were significantly increased, while the adult emergence was substantially reduced in the SpRS compared to SS. Adult longevity (male and female), fecundity, and hatching rates significantly decreased in the SpRS T. absoluta compared to SS. Additionally, the gene expression analyses indicated the down-regulation of development and reproduction-related genes (Vg, VgR, JHBP, JHAMT, JHE, and JHDK) in the SpRS population. Further, the mRNA expression level of the resistance-related cytochrome P450 gene CYP321C40, followed by CYP4M116, CYP6AW1, CYP339A1, and CYP6AB327, were significantly increased in the SpRS T. absoluta. Taken together, these results indicated that although T. absoluta developed a moderate level of spinosad resistance accompanied by fitness costs, continuous and indiscriminate use might elevate the resistance level. Overall, these findings provide important information about the trade-off between resistance degree and fitness cost that might be crucial to designing resistance management strategies against this key invasive herbivore.

Phthorimaea absoluta is a global constraint to tomato production and can cause up to 100% yield loss. Farmers heavily rely on synthetic pesticides to manage this pest. However, these pesticides are detrimental to human, animal, and environmental health. Therefore, exploring eco-friendly, sustainable Integrated Pest Management approaches, including biopesticides as potential alternatives, is of paramount importance. In this context, the present study (i) evaluated the efficacy of 10 Bacillus thuringiensis isolates, neem, garlic, and fenugreek; (ii) assessed the interactions between the most potent plant extracts and B. thuringiensis isolates, and (iii) evaluated the gut microbial diversity due to the treatments for the development of novel formulations against P. absoluta. Neem recorded the highest mortality of 93.79 ± 3.12% with an LT50 value of 1.21 ± 0.24 days, Bt HD263 induced 91.3 ± 3.68% mortality with LT50 of 2.63 ± 0.11 days, compared to both Bt 43 and fenugreek that caused < 50% mortality. Larval mortality was further enhanced to 99 ± 1.04% when Bt HD263 and neem were combined. Furthermore, the microbiome analyses showed that Klebsiella, Escherichia and Enterobacter had the highest abundance in all treatments with Klebsiella being the most abundant. In addition, a shift in the abundance of the bacterial genera due to the treatments was observed. Our findings showed that neem, garlic, and Bt HD263 could effectively control P. absoluta and be integrated into IPM programs after validation by field efficacy trials. [ABSTRACT FROM AUTHOR]

Using phototactic behavior to trap insect pests is one of the key options for Integrated Pest Management strategies. Opsin serves as a fundamental component of insect vision and plays a pivotal role in the phototropic behavior of insects. However, the functions of the opsin genes in Tuta absoluta, a devastating pest of tomatoes worldwide, remain elusive. In this study, four opsin genes, namely TaLW, TaBL, TaUV and TaUV-like, were cloned and identified from T. absoluta. Expression peaks for TaLW, TaBL and TaUV were observed in adults, whereas TaUV-like expression was highest in eggs. The four opsin genes exhibited the highest expression levels in compound eyes, while lower levels were observed in other tissues. After exposure to green and blue light, male TaLW and TaBL showed the highest expression levels at 20 min, whereas female TaLW and TaBL showed the highest expression levels at 25 and 15 min, respectively. In females, the expression levels of TaUV and TaUV-like opsins exhibited an initial increase followed by a decrease with prolonged UV exposure, whereas the pattern was reversed in males. The phototactic efficiency of T. absoluta towards green, blue, and UV light was significantly reduced upon silencing the three major opsins (dsTaLW, dsTaBL, and dsTaUV) respectively, and the phototactic efficiencies towards green, blue, and UV light were all significantly reduced upon combined knockdown of dsTaLW+dsTaBL+dsTaUV. The results revealed the functional role of opsin in T. absoluta and provided a theoretical basis for developing visual-cue based pest management techniques. [ABSTRACT FROM AUTHOR]

We explore the observed plasticity in Tuta absoluta age and size at pupation in response to water and nutrients scarcity. Using a minimal theoretical model, we demonstrate that the observed plasticity can be viewed as a strategic adaptation of individuals aimed at maximizing their reproductive output under stressful environmental conditions. T. absoluta plasticity is then found to align with expectations from fundamental principles of life history theory. [ABSTRACT FROM AUTHOR]

Mate choice is a fundamental behavior of polyandrous insects, in which individuals prefer mates that exhibit characteristic traits of higher reproductive quality. Tuta absoluta (Meyrick 1917) is the main pest in tomato cultivation and is difficult to control. Pheromones-based strategies; including monitoring, mass trapping and mating disruption; are recommended within integrated pest management of this pest. However, significant losses in tomato production are still reported despite the effective capture of males suggesting a potential failure of the used pheromones-based technologies in the field. As this situation may be related to the sexual behavior of this species, this study aimed to investigate how male's characteristics, such as body weight, mating status, and age, influence the reproductive behavior of T. absoluta females and thus understanding the reported efficacy losses. First, we conducted a set of tests in which females were allowed to choose between males of different weights, mating status, and age. The effects of mating with males presenting the most contrasting characteristics on the females, reproductive outputs and longevity were assessed. Our results show that females of T. absoluta prefer males with higher reproductive quality (young, virgin and heavy) and that the male's body weight had a direct influence on the increased longevity and reproductive performance of females. Understanding the reproductive success of these insects can help develop more effective control technologies to better reduce losses in tomato production caused by this pest. [ABSTRACT FROM AUTHOR]

Tuta absoluta (Meyrick) is a destructive pest of tomato crops. The cryptic nature of larvae often leads to low control efficacy. Sterile insect technique (SIT) has the potential to be an alternative management option for T. absoluta. In this study, the optimal dose for T. absoluta sterility was determined by estimating the effect of gamma radiation on parental generation (F0) and their descendants (first and second generation, F1 and F2). Adult emergence was not affected when T. absoluta pupae were exposed to gamma radiation at doses of 100~400 Gy. However, increasing doses of radiation increased deformed individuals and shortened their longevity. Furthermore, as the dose increased, F0 females showed decreased fecundity and fertility, and they were completely sterile when exposed to 300 Gy. The survival and sex ratio of females declined significantly in F1 of irradiated males with increasing doses. Moreover, we found that 300 Gy of gamma radiation did not affect the mating competitiveness of F0 males. Interestingly, this treatment caused a considerable reduction in the number of descendants and caused inherited sterility in F1 by lowering their fecundity and fertility. Therefore, the optimal radiation dose was 300 Gy, and the release of sterile adults may suppress T. absoluta population growth in the field. Our findings provide basis for controlling T. absoluta through SIT programs. [ABSTRACT FROM AUTHOR]

The tomato brown rugose fruit virus (ToBRFV) currently represents one of the most significant threats to tomato crop worldwide. Its transmission occurs mainly through contact between plants and infected surfaces, and only one case of mechanical transmission by arthropods has been reported. Here, we aim to assess the role of an invasive tomato pest, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), in ToBRFV transmission. Laboratory tests demonstrated the presence of the ToBRFV in adult moths obtained from larvae developed on ToBRFV-infected plants. Infected adults of T. absoluta were able to infect healthy tomato plants. In order to evaluate whether the occurrence of ToBRFV on T. absoluta adults was internal or external to the pupae, as results of larvae feeding on infected plants, pupae obtained from larvae fed on infected plants were externally disinfected and then analyzed for the presence of ToBRFV by RT-qPCR. Adults obtained from disinfected and not-disinfected pupae were also analyzed. Both adults and pupae were positive for the virus, suggesting its presence in the inner surface of the pupal exuvia. Electron microscopy, western blot analyses and hemolymph bioassay showed the absence of ToBRFV virions and viral coat protein in the hemolymph collected from disinfected pupae, demonstrating that the ToBRFV is not circulative in the progeny of T. absoluta adults obtained from larvae fed in infected plants, but probably adults got contaminated during their emergence, due to virus presence in the inner surface of pupal exuvia. This study demonstrates for the first time that T. absoluta can carry an infectious primary inoculum of ToBRFV, highlighting a potential epidemiological role of T. absoluta in spreading ToBRFV in the field. [ABSTRACT FROM AUTHOR]

Vitellogenin (Vg) is a glycolipid complex protein produced by the fat body of female insects. It plays vital roles in oocyte development and helps regulate reproductive development. In this study, we determined the grading criteria for ovarian development and identified a Vg gene (designated TaVg) from the devastating invasive pest, Tuta absoluta (Meyrick). TaVg contains a 5208 bp open reading frame encoding a protein of 1735 amino acids that includes conserved domain structures of insect Vg. Phylogenetic analysis indicated that TaVg was clustered into a clade with the Vg of other Lepidoptera species, suggesting this gene has been conserved during evolution. Spatiotemporal expression analyses showed that TaVg was highly expressed in the female pupae and adults. There was increased expression during sexual maturation, and the high expression level was found in the ovary and fat body. RNAi-mediated silencing of TaVg resulted in significant downregulation of vitellogenin contents and severely affected ovarian development. Females injected with dsTaVg had shorter ovarian tubes and fewer oocytes compared with the untreated individuals. The number of oocytes and the amount of yolk deposition in the egg chambers also reduced. Depletion of TaVg significantly reduced the number of eggs laid and the hatching rate. Co-silencing of TaVg and TaVgR had a more significant effect on inhibiting the ovarian development and reducing female fecundity of T. absoluta, showing that the two genes play important role in regulating the reproduction. Our results provide potential targets for developing RNAi-based pest management tractic on T. absoluta. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), has invaded most Afro-Eurasian countries. Since its first detection in China in late 2017, this pest has been now present in nearly 20 provinces/prefectures in China and is threating tomato and other Solanaceous crops such as potato, eggplant, and tobacco. Here, we provide a timely review on the current distribution, damage, management, and research in China. A standard survey form was designed and 30 answered surveys from 25 provinces have been received. The data showed that the damage has been witnessed in most of the regions despite that the severities vary among the regions. The management is chemicalcontrol biased, and more efforts are needed to increase the adoption of non-chemical alternatives in the Integrated Pest Management packages. An Integrated Pest Management (IPM) package called "CAMEFA" was developed and demonstrated in Yunnan and Xinjiang, the two earliest regions for the invasion. Yet, the adoption by local growers is still limited. Besides T. absoluta, we suggest a multi-pest approach by combining IPM tactics coping with other major insect pests sharing the crop. Lastly, international projects are deemed to serve as key lever for promoting IPM of T. absoluta and other invasive insect pests. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Tuta absoluta (Meyrick 1917) (Lepidoptera: Gelechiidae), is one of the main pests of tomato crops worldwide. The release of predatory mirids in protected crops has been proven to be effective in several countries. Macrolophus basicornis (Stal) (Hemiptera: Miridae) stands out as a promising biocontrol agent of T. absoluta. However, the release of this predator can be compromised by hazardous chemical insecticides. The present study aimed to evaluate the possible transgenerational effects of the insecticides chlorantraniliprole and flubendiamide on M. basicornis. The predator couples were treated with chlorantraniliprole and flubendiamide at the maximum doses recommended for the control of T. absoluta in Brazil. Thereafter, they were placed on tomato plants for oviposition. The life history parameters, including survival rate, nymph duration, adult and total pre-oviposition periods, longevity of male and female, oviposition period and female fecundity of the progeny from the couples treated with the insecticides were evaluated based on the age-stage, two-sex, life table. The longevity of females and males and the total life cycle duration were not reduced by the compounds. Neither chlorantraniliprole nor flubendiamide reduced the r and R0 parameters in the F1 generation, however, the mean generation time (T) was high in the chlorantraniliprole treatment (51.57 days) followed by the untreated control (48.85 days) and flubendiamide treatment (47.27 days). Nevertheless, careful consideration is warranted, as flubendiamide might adversely affect the fecundity of this predator. Applying both insecticides studied could be a promising option for managing T. absoluta in tomato crops where M. basicornis is present. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is considered one of the most economically important invasive pests that causes severe damage to tomato crops. The biopesticide spinosad is widely used for controlling T. absoluta. This study aimed to investigate the spinosad-induced intergenerational sublethal effects on T. absoluta. Results showed that spinosad exhibited high toxicity against 3rd instar T. absoluta with the LC50 of 0.04 mg L-1 after 72 h exposure. The LC10 and LC30 of spinosad significantly decreased the durations of various developmental stages and some reproductive parameters of parental (F0) T. absoluta compared to control. The developmental durations, survival rate, reproduction and life table parameters (intrinsic rate of increase, r; finite rate of increase, r; net reproductive rate, R0; and oviposition days, Od) were significantly decreased in the progeny generations (F1 and F2) following F0 exposure to the LC10 and LC30 of spinosad as compared to the control group. Additionally, the mRNA expression levels of development and reproduction related genes such as Vg, VgR, and JHBP were down-regulated in parental and progeny generations at both spinosad treatments as compared to control treatment. The resistance related cytochrome P450 genes CYP321C40 and CYP6AW1, followed by CYP4M116, CYP9A307v2, CYP15C1, CYP339A1, and CYP6AB327 were up-regulated at spinosad-treated groups in the parental and progeny generations of T. absoluta as compared to control. Overall, these results showed that although spinosad exhibited high toxicity and induces intergenerational sublethal effects on the parental and progeny generations, the indiscriminate and long-term application might causes resistance development in of T. absoluta. [ABSTRACT FROM AUTHOR]

The tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is an invasive and destructive pest worldwide that feeds on solanaceous plants. T. absoluta has become resistant to most insecticides in current use. Broflanilide is a novel meta-diamide insecticide, which can bind to a new site on the γ-aminobutyric acid receptor and efficiently control insect pests of the order Lepidoptera. In this study, the acute lethal effects of flubendiamide, tetraniliprole, cyantraniliprole, chlorantraniliprole and broflanilide and the sublethal effects of broflanilide on the 2nd instar larvae of T. absoluta were assessed by leaf dip method. Among the five insecticides tested, broflanilide was the most toxic to T. absoluta with a LC50 of 0.232 mg/L. The sublethal effects of broflanilide on T. absoluta were observed at LC10 (0.053 mg/L) and LC25 (0.107 mg/L) concentrations. After exposure to low lethal concentrations of broflanilide, the larval duration was significantly prolonged, whereas the pupation rate, emergence rate and fecundity of females were all significantly decreased in F0 generation. In F1 generation, broflanilide treatments resulted in a significant decrease in female fecundity. Moreover, life-table parameters of F1 generation including the mean fecundity (F), the net reproductive rate (R0), and the intrinsic rate of population increase (r) were significantly reduced, and the mean generation time (T) was increased when compared to the control. The lethal and sublethal effects of broflanilide on T. absoluta suggested that broflanilide has good potential for management of T. absoluta. [ABSTRACT FROM AUTHOR]

Tuta absoluta, an economically important pest threatening the global production of tomato crops worldwide, has recently invaded China. Owing to insecticide resistance, alternative control options are needed within the context of integrated pest management (IPM) programs. Augmentative biological control using indigenous natural enemies is a promising tactic for managing T. absoluta in newly invaded areas. In this study, the host suitability of four commercialized Trichogramma parasitoids in China (T. dendrolimi, T. japonicum, T. chilonis, and T. ostriniae) on T. absoluta eggs was evaluated in laboratory conditions. The control effectiveness of the most promising Trichogramma species was further tested at different release densities and frequencies in a greenhouse experiment. We found that T. chilonis was the most promising species parasitizing T. absoluta eggs, showing the highest parasitism rate, emergence rate, and female offspring sex ratio. The greenhouse experiment indicated that 600,000 parasitoids/hectare (20 parasitoids/plant) was the most effective release density, reaching 76% control effectiveness. Release frequency significantly affected the parasitism rate in the greenhouse. Two releases of 300,000 parasitoids/hectare on Day 1 and Day 4 was the most effective strategy, compared to one release of 600,000 parasitoids/hectare on Day 1. Our findings showed that augmentative biological control of T. absoluta by native Trichogramma parasitoids T. chilonis in China is feasible, and it could be included as part of IPM package against T. absoluta in China. [ABSTRACT FROM AUTHOR]

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is one of the main pests threatening tomato production worldwide. Since its detection in the Mediterranean basin, it has been the target of research aiming to reduce damage in tomato crops. Current conservation biological control approaches focus on the polyphagous predators Macrolophus pygmaeus (Rambur) and Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae), which are very effective predators of the pest's eggs but have little effect on T. absoluta larvae. Surveys conducted in northeast of Spain have concluded that the eulophid Necremnus tutae Ribes & Bernardo and the braconid Dolichogenidea gelechiidivoris (Marsh) are the most abundant larval parasitoids. It is well known that adding floral resources near crops can provide high-quality food for natural enemies and thus enhance biological control. Previous studies showed that Lobularia maritima L. (Brassicaceae) flowers are a reliable food source for N. tutae. The present study examines whether the availability of L. maritima flowers positively influences the fitness of D. gelechiidivoris and the biological control of T. absoluta by parasitoids. To study this aspect, the performance of both wasps was evaluated in a simple and complex arena at high and low densities of T. absoluta, respectively. Our results demonstrate that the nectar of L. maritima is a nutrient-rich food source for both N. tutae and D. gelechiidivoris with profound implications on the biological control of T. absoluta in tomatoes. [ABSTRACT FROM AUTHOR]

Since volatile organic compounds (VOCs) shape plant defenses against pests, ecologists strive to understand their sources of variation. The worldwide distribution of tomato offers an ideal system to explore the ecological diversity of VOCs produced by plants supporting a large range of local adaptations. In this study, we analyzed the diversity of VOC profiles released by 29 accessions of tomato belonging to five species with different natural histories and including domesticated plants and wild relatives. In addition, olfactometer assays were performed on 10 accessions characterized by strong differences in VOC emissions to test the consequences on host-plant location by a major pest specialized on solanaceous plants, Tuta absoluta. Based on 77 VOCs detected, our results suggest that the large diversity of volatile profiles reflect different biogeographic areas. A phylogenetic tree was constructed to test phylogenetic drivers in VOC emissions. The richness of volatile profiles and sesquiterpenoid emissions were relatively high in ancestral branches and decreased exponentially with evolution according to early-burst patterns. In olfactometer assays, we identified four repellent accessions belonging to S. pennellii, S. habrochaites and S. cheesmaniae. This study points out the importance of inter- and intra-specific diversity of VOCs in antixenosis. Further, our results suggest that methyl salicylate, ß-myrcene and sesquiterpenoids such as (3E,7E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene or a-curcumene could serve as repellents against T. absoluta. In a greenhouse, we confirmed the biological relevance of agroecological research interested in screening repellent plants. Bridging chemical ecology with phylogenetic approaches helps to better understand the evolution of mechanisms supporting anti-herbivore plant defenses. [ABSTRACT FROM AUTHOR]

The global tomato cultivation faces serious threats from the whitefly Bemisia tabaci (Gennadius) and the invasive tomato leafminer Tuta absoluta (Meyrick). Identifying new resistant sources and exploring resistance mechanisms is crucial for long-term management of these rapidly spreading insects. This study evaluated antixenosis and antibiosis resistance in wild tomato accessions of Solanum cheesmaniae and Solanum galapagense through trichome characteristics and various assays, revealing resistance to B. tabaci (Asia II 7 biotype) and T. absoluta. Wild accessions resulted in reduced oviposition, increased adult mortality of whiteflies, fewer whitefly developmental stages, disrupted leafminer developmental stages, and reduced adult emergence. Moreover, high densities of type-IV glandular trichomes in wild accessions correlated negatively with the resistance parameters of both insects, influencing their preference and performance. Variations in resistance parameters were identified between wild and cultivated accessions, with S. galapagense (VI063117-10) demonstrating superior resistance. This study emphasizes the significance of understanding resistance traits in wild accessions to manage pest insects with diverse feeding behaviors and utilize them in developing multiple insect-resistant tomato varieties. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Phthorimaea absoluta Meyrick, 1917 (=  Tuta absoluta), a significant pest of solanaceous crops globally, has been detected for the first time in Jeonbuk Province, Korea. It caused damage to commercial tomatoes, particularly in organic farms that do not use chemical pesticides. Additionally, damage was found on Solanum nigrum L. a common wild plant in Korea, emphasizing its potential to sustain populations even in the absence of cultivated hosts. Our research underscores the urgency of conducting further research and developing effective management strategies to mitigate its spread and damage. [ABSTRACT FROM AUTHOR]

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is the most destructive pest of tomato worldwide. Biological control has always been considered as a promising management approach of this pest in tomatoes. In this context, we evaluated the effectiveness of releasing Trichogramma cacoeciae Marchal parasitoids or Macrolophus pygmaeus (Rambur) predators in controlling T. absoluta in greenhouse tomatoes of northeastern Tunisia. Two weekly releases of either M. pygmaeus at 1 adult/m2 or T. cacoeciae at 20 adults/plant were assessed. Our results indicated that parasitism rates were significantly higher on the apical tomato leaves compared to the middle leaves. We found that the number of T. absoluta eggs and larvae was significantly reduced after releasing T. cacoeciae, while releases of M. pygmaeus did not significantly reduce T. absoluta densities. The present study demonstrated the great potential of releasing T. cacoeciae in controlling T. absoluta in greenhouse tomatoes of northeastern Tunisia. However, further studies are needed to evaluate other release rates of M. pygmaeus that could show promising effectiveness against T. absoluta in northeastern Tunisian greenhouses. [ABSTRACT FROM AUTHOR]

BACKGROUND: Tuta absoluta is an exotic species and a major pest of tomato crops in Europe. Macrolophus pygmaeus and Trichogramma achaeae are two biocontrol agents widely used in integrated pest management programs of the South American tomato pinworm Tuta absoluta. In this study, we evaluated under laboratory conditions the (i) voracity of M. pygmaeus females fed on single diets of Tuta absoluta eggs parasitized or unparasitized by Trichogramma achaeae, (ii) voracity and feeding preference of M. pygmaeus females provided with mixed diets of Tuta absoluta eggs unparasitized and parasitized by Trichogramma achaeae and (iii) effect of competitive and intraguild interactions between M. pygmaeus and Trichogramma achaeae on the number of Tuta absoluta eggs consumed and/or parasitized. Lastly, we assessed under field conditions the effect of interspecific and intraspecific interactions between natural enemies on the number of Tuta absoluta eggs consumed and/or parasitized. RESULTS: Macrolophus pygmaeus consumed more unparasitized than parasitized eggs of Tuta absoluta. Under mixed diet regimes, Manly indices revealed a feeding preference for unparasitized eggs, and a decrease in the total number of eggs consumed, as the proportion of available parasitized eggs increased, whereas the unparasitized eggs were consumed in direct proportion to their availability. Conspecific interactions between M. pygmaeus, in contrast to Trichogramma achaeae, revealed the possible occurrence of intraspecific competition. For intraguild heterospecific interactions, the number of Tuta absoluta eggs consumed by M. pygmaeus and parasitized by Trichogramma achaeae was lower than that predicted for additive and non‐interactive scenarios. Under field conditions, a significant difference between the conspecific treatment and heterospecific treatments revealed a slightly higher success rate in controlling Tuta absoluta when both M. pygmaeus and Trichogramma achaeae were used simultaneously. CONCLUSION: Macrolophus pygmaeus prefers unparasitized eggs of Tuta absoluta but inflicts intraguild predation on Trichogramma achaeae. In conspecific experiments, mutual interference between M. pygmaeus predators intensifies as the number of individuals increases, but for Trichogramma achaeae, it occurs in an unpredictable manner. Adding Trichogramma achaeae could significantly increase the level of control of Tuta absoluta compared to what could be achieved when only M. pygmaeus is present in glasshouse tomatoes. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm Tuta absoluta (Lepidoptera: Gelechiidae) has been considered among the most economically important pests affecting greenhouse crops heated by geothermal water in southern Tunisia. In this context, we studied from September 2019 to July 2020, the effectiveness of the mating disruption technique using Isonet®T dispensers and the attract-and-kill device SPLAT®TUTA against this pest in cherry tomato crops. The three biorational control options tested, Isonet®T alone (installed at transplanting), insecticide + Isonet®T (installed in January) and SPLAT®TUTA + insecticide, showed a high effectiveness against T. absoluta populations. Their field application resulted in a decrease in the number of T. absoluta males captured in water traps by 87.23%, 87.13% and 83.50%, in the egg number by 85.97%, 90.78% and 86%, and in the number of larvae by 65.35%, 65.61% and 80.36%, respectively, as compared to the untreated control. In addition, the use of the three control options reduced the infestation on leaves and fruits by more than 77.17% and 71.21%, respectively. The application of mating disruption and the use of biopesticides significantly reduced leaf and fruit damage. The percentage reduction in leaf and fruit damage was more than 77.17% and 71.21%, respectively, for the three treatments compared with the untreated control. On the other hand, the leaf and fruit infestation percentages did not exceed 12% and 2% for the three treatments, respectively. The study showed that mating disruption applied alone or in combination with bioinsecticides against T. absoluta was effective in heated greenhouses in southern Tunisia. This technique could be a key sustainable option of integrated pest management in tomato crops. [ABSTRACT FROM AUTHOR]

In Africa and Asia, fall armyworm (Spodoptera frugiperda) and South American tomato pinworm (Tuta absoluta) have become severe invasive pests of maize and tomato, respectively. They rapidly develop resistance to commercial pesticides. Therefore, there is an urge to integrate new eco-friendly pesticides into the management programs. Bamboo-leaf prickly ash, Zanthoxylum armatum (Za), is known to have insecticidal activities. We tested Za's n-hexane extract against these two pests. Median lethal concentrations (LC50) at 96 h after treatment (HAT) against second-instar S. frugiperda and T. absoluta larvae were 4.41 and 4.42 mL/L, respectively. At ≥ 22.0 mL/L concentration, the extract showed a 100% ovicidal effect against both the pest species. LCQTOF analysis revealed that fatty acids constituted ~ 95% of this extract; carboxylic acids and secondary metabolites such as alkaloids and flavonoids accounted for the remaining portion. Extract's foliar application also showed oviposition deterrence against these two pests. At ≥ 22.0 mL/L extract concentration, no S. frugiperda oviposition was observed. At ≥ 6.0 mL/L, extract reduced the T. absoluta oviposition by > six folds. To understand the basis of this deterrence, we conducted Za extract's GCMS analysis. It revealed that monoterpenes, sesquiterpenes, and their derivatives were the most abundant constituents (55%), followed by fatty acids and their derivatives (34%), and aromatic compounds (10%). We infer that this extract is a unique combination of antibiosis- and antixenosis-causing, shelf life-increasing, and activity-enhancing compounds. It can be a highly useful biopesticide for integrating into the S. frugiperda and T. absoluta management programs. [ABSTRACT FROM AUTHOR]

IntroductionThe south American tomato pinworm (Tuta absoluta), an invasive insect pest species, has established itself in more than 33 Chinese prefectures, where it is mainly damaging tomato crops. Immediate efforts have been initiated to find strategies to control this pest. Studies have shown that biochar (BC) amendment to soil can enhance plant growth and resistance to herbivory.MethodsFirst, we quantified the morphological performance of tomato plants grown in different coconut bran and bamboo charcoal (v/v) combinations and selected the most beneficial one. Then we checked the T. absoluta survival on the tomato plants grown in the selected bamboo charcoal combination. Finally, we studied the leaf metabolite accumulation and gene expression changes in tomato plants after growing in the selected bamboo charcoal combination.ResultsWe found that the 30:1 ratio of bamboo charcoal and coconut bran is the most beneficial to tomato growth as its amendment to soil increased tomato plant height, stem thickness, and chlorophyll content, whereas, the T. absoluta survival decreased. The metabolome profiles of BC tomato leaves showed an increased accumulation of flavonoids, terpenoids, and phenolic acids compared to CK. Transcriptome sequencing resulted in the identification of 244 differentially expressed genes. Most of the upregulated genes were associated with stress-related hub proteins, flavonoid biosynthesis, MAPK and phytohormone signaling, and terpenoid biosynthesis. Additionally, the expression of many genes related to signaling and defense was changed in response to the bamboo charcoal amendment.DiscussionWe conclude that bamboo charcoal induces biosynthesis of flavonoids, terpenoids, and phenolic acids, which improve plant growth and tolerance against T. absoluta, thus reducing the survival of destructive pests.

Tuta absoluta, an invasive pinworm characterized by high reproductive potential and adaptation to different agroecological conditions, cause serious damage to tomato crops. Chemical control with synthetic insecticides is widely used to control this pest, although pesticides exhibit side effects on non-target organisms and negatively impact the environment, with the occurrence of resistance to some active substances in the target pest. The use of essential oils (EOs) from aromatic or officinal plants could represent an environmentally safe control method, alternative to synthetic insecticide application. In this work we investigated the effect of EOs from Spanish oregano, laurel, basil, garlic, peppermint, cypress, and eucalyptus EOs on T. absoluta oviposition deterrence and larval repellency. Results showed a remarkable oviposition deterrence using laurel, Spanish oregano, basil, and garlic EOs in both laboratory and greenhouse experiments. In no-choice repellence tests carried 1, 2, 6, and 22 h after treatment application, peppermint and Spanish oregano EOs showed the most lasting effects while cypress and eucalyptus EOs were not effective after 6 and 22 h, respectively. In choice tests, at either 5 or 22 h after treatment application, low preference for the test over control by larvae was observed in all treatments, except for basil EO. The most promising effects were observed in Spanish oregano and laurel treatments where no larvae were detected. Repellent effectiveness of EOs does not seem to be influenced when larvae did not get a chance to do a choice between treated and untreated leaves. This study highlights the effectiveness of EOs of aromatic or officinal plants as an alternative to synthetic insecticides for the control of T. absoluta. [ABSTRACT FROM AUTHOR]

Macrolophus pygmaeus (Mp) and Nesidiocoris tenuis (Nt) are valuable biological control agents against Tuta absoluta. However, their predation rate on T. absoluta eggs over the entire plant has not been sufficiently studied. The aim of our study was to record the density and map the T. absoluta egg distribution per plant under different female densities. We also explored the predation rates of single (Mp/Nt), conspecific (2Mp/2Nt) or heterospecific pairs (MpNt) of predators on tomato plants on which T. absoluta eggs had been placed at the respective densities and sites as those selected by the T. absoluta females. The number of eggs laid per female was highest when the females were used singly. Females made active egg laying decisions preferring to oviposit on the 3rd and 4th leaves. Single M. pygmaeus showed a higher predatory efficacy than N. tenuis when 14 and 30 eggs were used per plant. Conspecifics of M. pygmaeus were more effective than N. tenuis at densities of 17 and 110 eggs. Interestingly, a pair was as effective as a single predator at 14, 17 and in many cases at the 30 and 110 egg/plant densities. The multiplicative model revealed that prey density has a strong impact on the effects of multiple predators on prey suppression. In all cases, 30% or more of the eggs were left unconsumed. These results suggest that the study of predation under field conditions and different pest pressure levels reveals useful information for the evaluation of predator efficacy in T. absoluta control. [ABSTRACT FROM AUTHOR]

Male annihilation and mating disruption provide limited success in the control of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) populations. The ability of T. absoluta to reproduce parthenogenetically, due to Wolbachia (Hertig) (Rickettsiales: Ehrlichiaceae) infection, has been reported as a possible contributing factor to the limited success of management strategies aimed at male moths. The genetic diversity in T. absoluta from four localities in South Africa were investigated by employing a fragment of the mitochondrial cytochrome c oxidase subunit I and Wolbachia strains were identified with the multilocus sequence typing scheme. Fecundity and fertility of parthenogenetically produced eggs and female lifespan were also recorded. High rates (≥ 95%) of infection with a single Wolbachia strain (ST41) occurred, but genetic diversity was low and consisted of only four haplotypes, one of which was novel. None of the eggs laid by unmated females were viable. Wolbachia infection in South African T. absoluta populations does not lead to either parthenogenesis or failure of pheromone-based strategies. [ABSTRACT FROM AUTHOR]

Simple Summary: Since the arrival of Tuta absoluta, a multivoltine insect species whose larvae develop in leaves, fruits, flowers, buds, and stems of tomatoes, producers are facing one of its biggest production challenges. The pest continues to invade new areas, causing heavy losses in the tomato value chain. Sprays of synthetic insecticides have shown very low efficacy on this pest because of its inclination to develop resistance to various insecticide-active ingredients. Biological control is one of the most promising solutions for the management of this pest. In this work, we investigated the most efficient indigenous parasitoids associated with T. absoluta in Kenya and their preferable habitat and ecological niche suitability. We identified two species, Stenomesius sp. near japonicus and Bracon nigricans, with up to 17% and 21% parasitism respectively. Stenomesius sp. near japonicus was more abundant in greenhouses and non-insecticide-treated tomatoes while B. nigricans was more abundant in the field tomatoes with a low abundance of Nesidiocoris tenuis. The ecological niche of these two species showed that B. nigricans was suitable for establishment in sub-Saharan Africa, a big part of South America, and Australia in both current and future scenarios. Associations between the South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), and its native parasitoids need to be updated to increase the implementation of pest control strategies. In this study, T. absoluta-infested tomato plants were collected from three regions in Kenya. The emerged parasitoids were identified, and their abundance was correlated with agroecological parameters, viz. cropping systems, and the abundance of the predator Nesidiocoris tenuis Reuter (Hemiptera: Miridae). The study further conducted a habitat suitability prediction for the identified parasitoids. Two parasitoid species, Bracon nigricans (Szépligeti) (Hymenoptera: Braconidae) and Stenomesius sp. near japonicus (Ashmead) (Hymenoptera: Eulophidae) emerged from T. absoluta immature stages, with parasitism rates ranging from 0 to 21% and 0 to 17% respectively. Insecticide application and open field cropping negatively influenced the parasitism by S. sp. nr japonicus. Low occurrence of N. tenuis positively affected B. nigricans parasitism. The predicted occurrence of parasitoid species indicated vast suitable areas for B. nigricans in sub-Saharan Africa, Australia, and South America. Low suitability was observed for S. sp. nr japonicus in Africa. Therefore, native parasitoids, especially B. nigricans could be considered for implementation as a biocontrol agent in the Integrated Pest Management program of T. absoluta. [ABSTRACT FROM AUTHOR]

Nanopesticides are novel formulations that can be applied against a wide range of insect pests as a sustainable alternative to less effective chemical pesticides. Here, acute toxicity of nano (abamectin-PLA-NS (1%) and abamectin-PLA-NS (0.1%)) and commercial formulations of abamectin was evaluated against the South American tomato pinworm, Tuta absoluta, in laboratory and open-field conditions in northeastern Tunisia. Additionally, side effects of nano and commercial formulations of abamectin were also investigated towards the two predatory mirids Macrolophus pygmaeus and Nesidiocoris tenuis either under laboratory or open-field conditions. Laboratory results of acute toxicity revealed no differences between the tested abamectin formulations (against T. absoluta larvae. LC50 values were 0.28, 0.23, and 0.23 for abamectin EC; 0.30, 0.18, and 0.18 for abamectin-PLA-NS (1%) and 0.57, 0.28, and 0.25 for abamectin-PLA- NS (0.1%) corresponding to three time intervals (24, 72 and 120 h after treatment). Abamectin EC, abamectin-PLA-NS (1%) and abamectin-PLA-NS (0.1%) applied at higher doses (0.6 mL/L and 1.2 mL/L) showed higher efficacy percentages (> 90%) in controlling T. absoluta larvae, fourteen days after treatment in open-field tomatoes. Commercial abamectin formulation showed higher toxicity toward M. pygmaeus adults and N. tenuis nymphs compared to nano formulations applied at the two aforementioned doses. High mortality rates, reaching 100%, were reported for M. pygmaeus adults exposed to 1 and 3 day-old residues for commercial formulation at 0.6 mL/L and 1.2 mL/L in laboratory conditions. However, in open-field tomatoes, low acute toxicity was induced by abamectin-PLA-NS (0.1%), ranging from 25 to 41.17%, compared to abamectin EC, ranging from 58.33 to 94.11%, and abamectin-PLA-NS (1%), ranging from 58.33 to 76.47%, at 0.6 mL/L against N. tenuis nymphs at apical leaves. For middle leaves, only abamectin-PLA-NS (0.1%) applied at 0.3 mL/L did not show significant toxicity against N. tenuis nymphs with low mortality level up to 7%, fourteen days after treatment. The practical implications of these results for enhancing integrated pest management programs of T. absoluta in tomatoes are discussed herein. [ABSTRACT FROM AUTHOR]

1. Fertilization input is required to improve productivity and attend the market demand for tomatoes. However, providing crops with nutrients can affect plant–insect interactions via bottom‐up effects. The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a main pest of tomato crops worldwide but little is known about the effects of macro‐elements fertilization inputs on its biological traits. 2. This study aimed to evaluate the effects of low, high and normal fertilization levels calcium, sulphur, nitrogen and potassium to tomato plants on T. absoluta development, survival and crop damage. 3. Larval mortality was lower in tomato plants fertilized with high sulphur fertilization level. The number of mines per leaf was not affected by calcium, sulphur and potassium fertilization, but low nitrogen input resulted in higher crop damage. Overall, our results indicate that nutritionally unbalanced tomato plants improve the biological performance of T. absoluta in comparison with balanced plants. 4. The results provide useful information that can be used in fertilization programmes of tomato and planning of strategies and tactics to reduce tomato suitability to T. absoluta. 5. In addition, the obtained findings provide an insight into the basic understanding of the interactions between crop fertilization and the performance T. absoluta. [ABSTRACT FROM AUTHOR]

[Display omitted] • The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a major invasive pest of tomato. • The weight and percentage of infected fruits was negatively related to different initial infestation levels of Tuta absoluta. • Investigating crop loss of T. absoluta in the farm is essential for enhancing integrated pest management programs. The South American tomato pinworm, Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), a devastating pest of tomato plants, originates from South America but it has been considered an invasive pest for Iran since 2010. To assess crop loss caused by this pest, a study was conducted in a 600 m2 field under a randomised complete block design. The impact of different initial densities of T. absoluta , including control (without infestation), one, two, four, and eight T. absoluta eggs on each host plant in the first and second year was investigated with an additional treatment (16 pinworm eggs per host plant) used in the second year. Yield attributes including length and width of fruits, numbers of infested and intact fruits along with their weights were sampled and assessed on a weekly basis. In addition, the correlation between the number of galleries and these characteristics was also investigated. Crop loss data demonstrated that the effect of different infestation levels on fruit size and the weight of intact fruits was not significant over both years. However, the effect of treatment on the percentage and weight of infested fruits was shown to be significantly different in 2014 and 2015. Furthermore, there was a negative significant correlation between the number of galleries and weight of infested fruits in both years. Collectively, these results will be useful for enhancing pest management programs of T. absoluta in Iran. [ABSTRACT FROM AUTHOR]

This study aimed to compare the susceptibility of tomato pinworm, Tuta absoluta, from four Brazilian regions to insect growth disruptor (IGD) insecticides by tomato leaf-dip bioassays. Larval mortality was assessed seven days after exposure to insecticide-treated leaves. The control failure likelihood (CFL) was estimated after larval bioassays with IGDs recommended label rate. Mortality data were subjected to Probit and variance analysis. All populations of tomato pinworm showed significant resistance to one or more insecticides. The LC50 values ranged from 0.34 to 0.63 g L−1 (chlorfluazuron), 0.17 to 0.92 g L−1 (teflubenzuron), 0.13 to 1.28 g L−1 (novaluron), 0.29 to 0.46 g L−1 (lufenuron), and 0.71 to 4.60 g L−1 (methoxyfenozide). The resistance ratios varied from 1.2 to 1.8-fold (chlorfluazuron), 1.4 to 5.5-fold (teflubenzuron), 1.2 to 9.9-fold (novaluron), 1.0 to 1.6-fold (lufenuron), and 1.5 to 6.5-fold (methoxyfenozide). Despite the low resistance ratios (< 10-fold), all populations showed low mortality and CFL > 54%, indicating likely control failure at the IGD label rates. We detected significant variations among populations of T. absoluta for activity of enzymes glutathione S-transferases (GST), cytochrome P450-dependent monooxygenases (MFO) and α-esterase (EST), however there was no significant difference between the populations for activity of β-esterase (EST). The evolution of resistance in T. absoluta populations to IGDs observed in this study is likely due to high selection pressure, demanding insecticide resistance management practices and environmentally sustainable tactics to obtain a more effective control of this pest. [ABSTRACT FROM AUTHOR]

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is among the most devastating pests worldwide of solanaceous plants, particularly of tomato (Solanum lycopersicum L.). Since its recent introduction into sub‐Saharan Africa, it has become an additional widespread tomato pest throughout the region. When no control measures are taken, yield losses caused by T. absoluta larvae can reach 100%. Chemical control remains the primary management option despite its many adverse effects and increasing inefficiency due to the species' endophytic habits and ability to develop insecticide resistance. Safer and more effective alternatives are therefore urgently required. Here, we investigated the effectiveness of two bioinsecticides compared to that of a widely used deltamethrin‐based synthetic insecticide, in preventing damage caused by T. absoluta larvae to tomato leaves and fruits, thereby affecting tomato yield. A field trial was conducted in 2018 and 2019 in northwestern Senegal using a randomized complete block design. Damage caused by T. absoluta affected approximately 65% of total leaf area and 3–24% of the fruits. Damage to the leaves caused by other insect species or other factors was less significant. At the dose applied, the chemical insecticide did not significantly reduce the surface area of leaflets affected by T. absoluta or other causal agents, the number of T. absoluta mines on the leaflets, or the proportion of fruits damaged. In contrast, the azadirachtin and Bacillus thuringiensis (Bt) formulations rapidly and significantly reduced damage to both leaves and fruits. The proportion of fruits damaged was reduced by a factor two and the total tomato yield was improved, particularly when the Bt formulation was used. In addition to their effectiveness in reducing damage caused by T. absoluta larvae to tomato leaves and fruit, and increasing the yield of marketable fruits, the viability of these organic alternatives was shown. The scope of our results is discussed in the context of T. absoluta control, in particular in integrated pest management programmes for tomato crops. [ABSTRACT FROM AUTHOR]

Tuta absoluta is a devastating invasive pest worldwide, causing severe damage to the global tomato industry. It has been recorded recently in the northwestern border areas of China, posing a significant threat to tomato production. It was presumed that the region's winter-related low temperatures would avert the alien species from successfully overwintering. In this study, the supercooling capacity and low-temperature tolerance of this pest were examined under laboratory conditions and its overwintering potential in Xinjiang was estimated. The results showed that the lowest supercooling point was recorded in the adult stage (− 19.47 °C), while the highest (− 18.11 °C) was recorded in the pupal stage. The supercooling points of pupae and adults were not influenced by gender. The Ltemp50 and Ltemp90 of female and male adults were the lowest when exposed to cold for 2 h. However, when the duration of exposure extended from 4 to 10 h, the Ltemp50 and Ltemp90 of female and male pupae were the lowest. Comparison of the lowest Ltemp50 and Ltemp90 with temperatures in January indicated that T. absoluta might not be able to overwinter in most of the northern and central regions of Xinjiang. However, in the southern regions, the extremely low temperature was higher than the Ltemp90, suggesting that T. absoluta has a higher overwintering potential in these regions. These results form a basis for predicting the dispersal potential and possible geographic range of this pest in Xinjiang. In addition, our findings provide guidance for the control of this pest by reducing overwintering shelters. [ABSTRACT FROM AUTHOR]

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a key insect pest, seriously damaging tomato crops and inducing tremendous yield and economic losses. The area of origin of this insect is in South America, while it has recently become an invasive pest in Europe, Africa, Asia and Central America. In the Middle East and North Africa (MENA) region, there has been growing evidence that biological control through field releases of egg parasitoids and predatory mirids generally induces promising control results of T. absoluta whenever the natural enemy species as well as the timing and release rates are suitably chosen. As such, application of botanical and/or microbial pesticides represent a potential control approach to be adopted against T. absoluta. This would decrease the detrimental side effects on non-target beneficial arthropods typically exhibited by hazardous chemical insecticide applications. The scientific literature emphasizing the (i) releases of parasitoids and/or predators, (ii) applications of biopesticides, and (iii) combination « release of parasitoid and/or predator + biopesticide treatments and/or other biorational tools», as sustainable control options of T. absoluta throughout the MENA region over the last decade, is comprehensively reviewed and unraveled herein. [ABSTRACT FROM AUTHOR]

• Tomato leaf miner is one of the most destructive tomato pests. • Predatory mirid bugs are very effective biocontrol agents. • Nesidiocoris tenuis uses herbivore-induced plant volatiles to find its prey. • Nesidiocoris tenuis prefers infested tomato plants by T. absoluta than healthy plants. The Zoophytophagous predator, Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) is one of the most important candidates for controlling Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in tomato crops. This predator uses different signals including morphological plant traits, prey insects, and volatile substances produced by the infested plants and prey signals to find its suitable prey. These signals are different in each cultivar of a plant. We aimed to understand how N. tenuis finds its prey using volatiles from tomato plants damaged or infested with T. absoluta. The predator's responses to various plant treatments on two cultivars of tomato plants were tested in a flight tunnel and a four-choice olfactometer. The volatile compounds released from the treatments were also collected and identified. The results of the olfactory experiments showed that the predators even in the absence of light chose the plants bearing their insect prey. This behavior was not the same in both cultivars, and N. tenuis had a tendency toward mechanically damaged of Early Urbana Y cultivar more than Cal JN3 cultivar. The differences in the amount of monoterpenes, sesquiterpenes, and eugenol between cultivars may play a role in the differential attraction of N. tenuis towards infested plants. The difference in the volatile compounds was evident in two cultivars, and this was consistent with our bioassay results. Therefore, the choice of appropriate cultivar and use of herbivore-infested plant volatiles are important for developing a control strategy against T. absoluta and attract its predators. [ABSTRACT FROM AUTHOR]

The damsel bug, Nabis pseudoferus Remane (Hemiptera: Namidae), is a generalist predator of small arthropods, including key insect pests of vegetable crops. In this study, we characterized the predation and development of various N. pseudoferus life stages when preying on the eggs and first‐ and fourth‐instar nymphs of the invasive South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae). These findings were compared to those of the bug's common prey, cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae). Of the life stages tested, females showed the highest predation rate on all tested prey, due to their high longevity, large body, and great energy requirements for reproduction. The predator's oviposition rate was clearly influenced by prey type, and was highest when feeding on fourth instars of T. absoluta. Considering the zoophytophagy of most of the life stages of other mirid species of tomato, and the lower propensity of N. pseudoferus to feed on plants, these results show that this species can be considered as a key indigenous natural enemy for sustainable pest control packages against T. absoluta in newly invaded areas. [ABSTRACT FROM AUTHOR]

The efficacy of mating disruption with Isonet®-T at the rate of 30, 45 or 60 g a.i. ha –1 of sex pheromone to control Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in greenhouse tomato crops was compared with conventional insecticides (flubendiamide, 60 mg L–1 and azadirachtin, 3 g L–1) in winter and summer. In both trials, significantly fewer moths were captured in mating disruption and insecticide-treated plots compared with the control. Differences in male captures between plots disrupted with 60 g a.i. ha –1 of sex pheromone and the insecticide-treated was significant only in summer. In plots disrupted with 60 g a.i. ha –1 of sex pheromone, male captures were significantly reduced by 90% in both trials. No significant differences were found in foliage and fruit damage between plots disrupted with 60 g a.i. ha –1 of sex pheromone and the insecticide-treated. The lower pheromone doses did not achieve a reduction in moth population, foliage, or fruit damage compared with the high pheromone dose or the insecticide treatments. The results suggest that mating disruption applied at high doses could be as effective as insecticides in managing T. absoluta, and could serve as a key component of an IPM program for the pest. [ABSTRACT FROM AUTHOR]

Herbivore-induced plant volatiles (HIPVs) and host sex pheromones are important semiochemicals used by natural enemies to locate prey or hosts. The egg parasitoid Trichogramma achaeae Nagaraja & Nagarkatti has recently shown potential for use as a biological control agent of Tuta absoluta (Meyrick), a key pest of tomato crops worldwide. In this study, we used olfactometer tests to examine the behavioral response of T. achaeae females to T. absoluta sex pheromone or to HIPVs produced by tomato plants infested with T. absoluta eggs or larvae. Our results showed that T. achaeae was attracted to T. absoluta sex pheromone. Parasitoids were also innately attracted to volatiles produced by tomato plants, whether uninfested or infested. However, parasitoids could not distinguish between volatiles from uninfested or T. absoluta-infested tomato plants. We characterized the headspace volatiles of tomato plants used in the olfactometer tests and found out that oviposition and larval feeding by T. absoluta significantly enhanced HIPV emission. This study suggests that the sex pheromone of T. absoluta is a potential tool to manipulate the behavior of T. achaeae and improve its attraction to the tomato crop. The analysis of volatiles released by tomato plants, either infested or uninfested, coupled with the response of T. achaeae in the olfactometer tests was consistent with what was expected in terms of the foraging behavior of a generalist parasitoid. The results and implications are further discussed in the context of sustainable T. absoluta management. [ABSTRACT FROM AUTHOR]

Tuta absoluta is one of the most devastating pests of fresh market and processing tomatoes. Native to South America, its detection was confined to that continent until 2006 when it was identified in Spain. It has now spread to almost every continent, threatening countries whose economies rely heavily on tomatoes. This insect causes damage to all developmental stages of its host plant, leading to crop losses as high as 80–100%. Although T. absoluta has yet to be found in the USA and China, which makes up a large portion of the tomato production in the world, computer models project a high likelihood of invasion. To halt the continued spread of T. absoluta and limit economic loss associated with tomato supply chain, it is necessary to develop accurate and efficient methods to identify T. absoluta and strengthen surveillance programs. Current identification of T. absoluta relies on examination of morphology and assessment of host plant damage, which are difficult to differentiate from that of native tomato pests. To address this need, we sequenced the genomes of T. absoluta and two closely related Gelechiidae, Keiferia lycopersicella and Phthorimaea operculella, and developed a bioinformatic pipeline to design a panel of 21-SNP markers for species identification. The accuracy of the SNP panel was validated in a multiplex format using the iPLEX chemistry of Agena MassARRAY system. Finally, the new T. absoluta genomic resources we generated can be leveraged to study T. absoluta biology and develop species-specific management strategies. [ABSTRACT FROM AUTHOR]

Dicyphus bolivari Lindberg and Dicyphus errans (Wolff) (Hemiptera: Miridae) are naturally widespread in many crops with low-pesticide pressure, where they prey upon several arthropods, including the tomato pinworm Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae). However, their efficacy as biological control agents (BCAs) of this pest needs further investigations. Therefore, in this study the predatory efficacy of D. bolivari and of D. errans on T. absoluta was evaluated on tomato in laboratory and greenhouse trials. Their functional response to different numbers of T. absoluta eggs (up to 350) offered to single females or 5th-instar nymphs for 24 h was assessed in laboratory. Females and nymphs of both predators showed a high voracity and a type II functional response, with an estimated maximum predation rate per day of 189 and 194 eggs for D. bolivari females and nymphs, respectively, and 197 and 179 eggs for D. errans females and nymphs, respectively. The predators showed similar predation rates of T. absoluta eggs on plants in cage trials. However, our greenhouse trial showed that the commonly used Macrolophus pygmaeus (Rambur) (Hemiptera: Miridae), which has a lower individual predation capacity than D. bolivari and D. errans, was more effective in controlling T. absoluta than D. errans and D. bolivari because of its stronger numerical response to densities of T. absoluta and supplemental food than the other two predator species. This shows that long-term greenhouse trials, which include functional and numerical responses to pest densities, are essential to evaluate the efficacy of an omnivorous predator. [ABSTRACT FROM AUTHOR]

We conducted a review of published information on Tuta absoluta parasitoids for the Neotropical region to (1) corroborate species records, (2) analyze associations including the T. absoluta, other insect and plant hosts and (3) identify research directions for enhancing their use as biological control agents. The literature review shows more than 50 species or morphospecies of Hymenoptera associated with T. absoluta, but less than a half (23) could be confirmed as parasitizing T. absoluta. Erroneous reports or invalid names of species, two new species records were found. Over a 100 pests and non-economically important insect and cultivated and non-cultivated plants directly or indirectly interact with T. absoluta in the region. Four T. absoluta parasitoid species include in their host range predatory insects or act as hyperparasitoids, a negative feature considered for a biological control agent. Five larval parasitoids have a narrow host range and could be considered for classical biological control programs in the areas of new invasion. Six Trichogrammatidae species are commercially used in various countries; of those, T. minutum and T. pretiosum are considered to be moderately generalist, being able to exploit several insect hosts. Apart from Apanteles gelechiidivoris and Pseudapanteles dignus, other native species have been the subject of field studies as biological control agents. The review presented here provides useful insights for identifying species that deserve further evaluation as T. absoluta biological control agents through augmentative or conservation strategies in South America, as well as for potential classical biological control programs in other continents. [ABSTRACT FROM AUTHOR]

The development of new strategies to control pest insects is required, in combination with conventional pesticides or replacing them. Essential oils produced from botanical extracts used in management programs should be effective against pests and selective to natural enemies. Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is one of the most destructive pests of solanaceous crops in the world, and a possible management strategy consists of releases of the predator Nesidiocoris tenuis (Hemiptera: Miridae), along with botanical applications. The objective of this study was to evaluate the effects of Prev-am® oil on T. absoluta offspring, either with or without the predator N. tenuis, as well as the oil's effects on N. tenuis predatory behavior and longevity. The oil's effects were compared with distilled water (control) and a synthetic pesticide (lambda-cyhalothrin). The response of populations to lambda-cyhalothrin was similar to that with Prev-am®, compared to the control, showing that N. tenuis had higher capacity to reduce T. absoluta populations. The survival analysis of predators exposed to Prev-am® indicates that none of the concentrations differed significantly from the control. In addition, the canonical variate analysis indicated significant overall differences in the predator behavior submitted to different treatments, suggesting that synthetic pesticide treatment affected predator behavior when compared to control and Prev-am®. Reduction in predatory voracity of N. tenuis adults exposed to leaves treated with pesticide and biopesticide was significant compared to the control treatment. The results obtained could improve IPM programs against T. absoluta through the Prev-am® applications and N. tenuis releases. [ABSTRACT FROM AUTHOR]

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), a pinworm native to South America, has invaded Tunisia, as well as the whole African continent, since 2008 inducing severe crop damages and substantial economic losses in all tomato-producing areas. During the last decade, several research studies and management efforts have been performed in an attempt to find out the most effective and sustainable pest control options against this devastating pest. Herein we explore, comprehensively summarize and discuss the most up-to-date state of scientific knowledge regarding bio-ecological aspects of the pest, its indigenous natural enemies and all categories of management strategies adopted so far against this economic pest in Tunisia. [ABSTRACT FROM AUTHOR]

Specifying the relationship between pests and their host plants in terms of damage is one of the basic concepts of integrated pest management (IPM) programmes. The crop loss and economic injury level (EIL) of Tuta absoluta (Lepidoptera: Gelechiidae) were determined on different tomato cultivars using gain threshold (field experiment) and regression (semi‐field experiment) methods. By assessing the crop loss in 2015 and 2016, four out of seven infested tomato cultivars had a significant yield loss in terms of weight of total fruits versus the control under the open‐field conditions. However, the total number of tomato cultivars had no significant difference to control treatment. The semi‐field experiment included six treatments (0, 2, 4, 6, 8 and 10 gravid females/plant) and examined two tomato cultivars. The tomato cages with between 6 and 10 gravid females/plant showed the highest number and weight of damaged fruits. Based on pesticide control costs, the market value of tomato and the control efficacy, we determined the EIL for T. absoluta. In the field experiment, the EIL value for T. absoluta on "Petomech," "Cal JN3," "Rio Grande" and "Early Urbana Y" cultivars was 4.15, 4.47, 4.70 and 5.04 larvae per plant, respectively. Based on regression equations, we calculated the EIL values for T. absoluta on "Cal JN3" and "Early Urbana Y" to be 4.75 and 5.44 larvae/plant, respectively. Crop loss assessment and EIL are necessary components of cost‐effective IPM programs and can be effective tools for making decisions about the application of pesticides against T. absoluta. [ABSTRACT FROM AUTHOR]