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Tuta absoluta, known as the South American tomato pinworm, is one of the most disastrous pests of tomato cultivations, presently menacing tomato cultivations worldwide. In 2006, T. absoluta invaded Spain from South America. Since then, it was rapidly spread to most European, African and Asian countries. Such alien invasive species can minimize crop production, whereas the increasing use of insecticides raises various environmental concerns as well as on control costs, control failure and the toxicity to non‐target organisms. The S. American tomato pinworm is mostly controlled by chemical insecticides, and failure to control it is not a rare phenomenon. Resistance to numerous insecticides has been reported and is mainly due to the fact that farmers do not follow a sustainable resistance management scheme. Several examples have been reported from several countries where the tomato pinworm is present. In order to develop a successful insecticide resistance management (IRM) strategy for any major pest, one needs to identify the baseline toxicity to insecticides and then monitor susceptibility levels. In Cyprus, the current status of susceptibility levels to the main insecticides that are used to control T. absoluta has never been studied before. Herein, nine Cypriot populations of the pest were subjected to laboratory bioassays between 2016 and 2018 using the main insecticides applied against it. We found that the insecticides chlorantraniliprole and indoxacarb could not control the Cypriot T. absoluta populations anymore, with a resistance ratio (RR) >28 and 3–23, respectively. Furthermore, mortality achieved by those two insecticides was 20.6%–72% for chlorantraniliprole and 27.5%–78% for indoxacarb. However, the insecticides emamectin benzoate and spinosad are very effective, since mortality to both of them ranged between 99.5% and 100%. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a serious threat to tomato and can occur on other solanaceous crops worldwide. Here we evaluated the development time, fecundity and longevity of T. absoluta on three different host plant cultivars grown in Tunisia: tomato (cv. "Sankara"), potato (cv. "Spunta") and eggplant (cv. "A336"), under controlled laboratory conditions. Results showed a higher capacity of T. absoluta to develop on tomato with a shorter development time (about 31 days) and a higher fecundity (20.47 eggs per female) and longevity (14 days) compared to developing on either potato or eggplant. The development time (egg to adult) of T. absoluta on tomato plant was longer at both lower temperature (21 °C), as compared to the higher 28 °C, and higher relative humidity (either 52 or 72%), as compared to the lower 32% relative humidity. Fecundity of T. absoluta females on tomato plant was highest at 28 °C and 52% relative humidity, as compared to that obtained at 21 °C. The present study provides evidence that host plant, temperature and relative humidity are factors that greatly influence key biological parameters of T. absoluta. The obtained results would be useful for developing and implementing suitable control strategies for this major economic pest. [ABSTRACT FROM AUTHOR]

From March to June 2018, we performed an insect survey in four tomato fields located in the South Department of Haiti. Although crop rotations and insecticide applications are regularly performed on these fields, insect pests repeatedly cause damage to plants and fruits. Leafminer larvae and adults were captured and further identified as Tuta absoluta Meyrick (Lepidoptera: Gelechiidae). This is the first record of this important tomato pest in Haiti. Early conversations with growers suggest that the insect is experiencing a year of unprecedented outbreaks. We expect growers to increase the frequency and doses of insecticide treatments, accelerating the development of insecticide resistant populations. The presence of T. absoluta in Haiti will probably result in a fast expansion to the neighbouring Dominican Republic, and could serve as additional reservoir for dissemination to American countries. [ABSTRACT FROM AUTHOR]

Tuta absoluta (Meyrick) is a key insect pest of tomato crop causing major economic losses worldwide. Biological control using Trichogramma parasitoids is considered a promising, eco-friendly management tactic of this pest. We performed inundative releases of Trichogramma cacoeciae (Marchal) (Hymenoptera: Trichogrammatidae) against T. absoluta in Takelsa (northeastern Tunisia). Three weekly releases of either (i) 10, 20 or 30 Trichogramma per plant in protected (greenhouse) tomato crops or (ii) 20 or 40 Trichogramma per plant in open field tomatoes were evaluated for their effectiveness. Results indicated that 20 Trichogramma per plant was the most effective release rate in significantly decreasing the pest's life stage densities. Parasitism rates were significantly higher on apical tomato leaves (estimated at 58.6% for the rate 20 Trichogramma per plant in greenhouses and at about 56% for the rate 40 Trichogramma per plant in open field) compared to those observed on middle leaves (24.6% and 45.26% for rate 2 respectively under greenhouse and open field conditions). Furthermore, the overall number of T. absolua eggs and larvae was significantly reduced after releases of Trichogramma parasitoids. These results clearly indicate that T. cacoeciae could be a promising biocontrol agent of T. absoluta in the largest tomato-producing area in Tunisia. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a devastating invasive pest of tomato crops in several areas around the world including Africa. Here, we comprehensively review and discuss the relevant scientific knowledge on its occurrence, biological and ecological aspects, fortuitous insect natural enemies, and potential advantages and constraints of pest management scenarios adopted against this pest in tomato crops in both Northern and Sub-Saharan Africa. We conclude the manuscript with a comprehensive research agenda providing future priorities towards sustainable control of this important tomato pest. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a devastating pest currently threatening the global tomato industry worldwide. In the last 10 years, it has spread and expanded to most of Europe, Africa and Asia, causing extensive damage to the crop itself and to the international tomato trade. With the aim of providing an overview of the current knowledge on this pest, we have briefly reviewed the available literature relying on its spread, quarantine, modeling and management. Finally, we have underlined the gaps in knowledge and provided several recommendations on how to achieve sustainable control as well as how to prevent further spread into unaffected areas. [ABSTRACT FROM AUTHOR]

The South American tomato leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a devastating pest in tomato crops. After having spread rapidly in the Mediterranean area since its first detection in 2006, it has recently become established in greenhouses in Western Europe. It was assumed that the low temperatures commonly associated with the winters in this area would prevent this exotic species from successful overwintering. However, the observed presence of T. absoluta at the start of the growing season in Belgium sparked a study on its potential to overwinter in Western Europe. In this study, the insect's cold hardiness and overwintering potential was assessed by determining: (1) the supercooling point (SCP) of larvae, pupae, and adults, (2) the lower lethal time (LT) for these stages at 0 and 5 °C, and (3) the reproductive diapause incidence, as indicated by the reproductive performance of females reared at two temperatures (18 and 25 °C) and two photoperiods [16:8 and 8:16 (L:D) h]. The mean SCP recorded for pupae (−16.7 °C) was significantly higher than for adults (−17.8 °C) and larvae (−18.2 °C). Based on estimates of the LT adults demonstrated better cold hardiness than larvae and pupae at both 0 and 5 °C with the median LT of adults averaging 17.9 and 27.2 days, respectively. No reproductive diapause was observed under the tested regimes. The results of this study indicate that T. absoluta is likely to successfully overwinter between two successive tomato crops in commercial greenhouses in Western Europe. [ABSTRACT FROM AUTHOR]

Dolichogenidea gelechiidivoris (Marsh) (Syn. Apanteles gelechiidivoris) (Hymenoptera: Braconidae), a konoibiont larval endoparasitoid of the South American tomato pinworm Tuta absoluta (Meyrick), was imported into Kenya in 2017 for the first classical biological control of T. absoluta in Africa. We determined the thermal thresholds of D. gelechiidivoris , with T. absoluta as host, using life cycle simulation modelling. Life-table data of D. gelechiidivoris were generated at six constant temperatures (10, 15, 20, 25, 30, and 35 °C, 65 ± 5% RH, and 12L: 12D photoperiod). Multiple non-linear functions were fitted to model some aspects of the biology of the parasitoid, including its longevity, mortality, reproduction, and senescence using Insect Life Cycle Modelling (ILCYM) software. The phenology models established were used to estimate life table parameters. Except at 35 °C, D. gelechiidivoris completed its development (i.e., egg-larval-pupa-adult) at all tested temperatures. The minimum temperature threshold from egg to cocoon was 7.0 °C and 5.9 °C from cocoon to adult wasp, while the maximum temperature thresholds were 34 °C and 36 °C, respectively. The optimal temperature for immature survival was 20–25 °C, while fecundity was optimum at 22.5 °C, with 69.5 eggs per female. Simulations of the population growth parameters indicated that the intrinsic rate of increase (rm) was maximum at 20 °C with 15 daughters per female per generation. Based on our findings the release of D. gelechiidivoris for inoculative augmentation in countries with temperatures ranging between 15 and 30 °C could be considered to control the pest. • Temperature effects on Dolichogenidea gelechiidivoris were studied using life cycle simulation modelling. • The parasitoid completed its development between 10 and 30 °C. • Its intrinsic rate of increase (rm) was maximum at 20 °C. • Regions with temperatures of 15–30 °C could be considered suitable for the releases. [ABSTRACT FROM AUTHOR]

Phthorimaea absoluta is an invasive pest and a major threat to tomato production in sub-Saharan Africa, including Tanzania. Although chemical pesticides are commercially available and used locally, mis- and overuse can cause detrimental effects on human and environmental health, and can lead to emergence of resistance among populations of P. absoluta within a short period, increasing production costs among smallholder farmers in Tanzania. The effectiveness of alternative options, such as the use of biological control agents and pheromone traps, has not yet been studied in the field in sub-Saharan Africa. The present study evaluated the effectiveness of a commercially available biopesticide based on Metarhizium anisopliae and pheromone traps for managing P. absoluta in field conditions in Tanzania during the dry and wet season, and compared effectiveness with chemical pesticides (a combination of chlorantraniliprole, emamectin benzoate, spinetram and flubendiamide) and untreated plants as a positive and negative control, respectively. The two field experiments were conducted in a randomized complete block design with three replications per treatment. Two weeks after transplanting, 20 plants were randomly selected from each plot, with the number of fully expanded leaves per plant and mines per plant counted at 7-day intervals until harvest. At harvest, the number and weight of damaged and marketable fruits were recorded, and yield and marketable yield per plot calculated. The number of leaves per plant (an indicator of P. absoluta infestation) was higher in the wet season than in the dry season. In the wet season, M. anisopliae -treated plants contained more leaves than plants in control or pheromone-treated plots. The number of P. absoluta mines per plant was higher in the dry season than in the wet season. In the dry season, the number of mines per plant was higher in control plots than in plots of other treatments. However, total yield and marketable yield were higher during the dry season than during the wet season. During both seasons, damage was highest and yield lowest in control plots. During the dry season, total yield and marketable yield did not differ significantly between pesticide-treated and M. anisopliae -treated plots. Biological control using M. anisopliae could be integrated in field management of P. absoluta in tomato in the highlands of Tanzania as well as in other regions of this country and throughout Africa. [Display omitted] • Phthorimaea absoluta is a major threat to tomato production in sub-Saharan Africa. • The efficacy of a biopesticide and pheromone trap was assessed in Tanzania. • Mass-trapping of P. absoluta with pheromone traps is unlikely to increase yield. • Metarhizium anisopliae application reduces damage and population densities of P. absoluta. [ABSTRACT FROM AUTHOR]

Tuta absoluta is a key pest of tomato crops originating from South America. The consequences of X-radiation on this species were studied under laboratory controlled conditions. The effect of radiation on adult emergence was evaluated exposing male and female pupae to increasing X-rays. Adult emergence decreased as doses of X-radiation increased, with the appearance of deformities such as malformed wings and bent legs at doses ≥350 Gy. Besides, males and females obtained from irradiated pupae were out crossed with untreated counterparts to explore the effects of X-radiation on inherited sterility. (a) Irradiated male × untreated female crosses. Both fecundity and fertility of the untreated females were reduced by radiation, and the effect was stronger as the doses increased. Neither the longevity of parental males and F1 adults nor the sex ratios of the F1 and F2 generations were affected by X-radiation (F1 and F2: first and second generation of descendants of irradiated adults). Inherited sterility effects were manifested by a significant reduction in the F1 fecundity, F1 fertility, and the amount of larvae and pupae produced. Doses of 200-250 Gy could be used to induce inherited sterility in T. absoluta males. (b) Untreated male × irradiated female crosses. The minimum dose at which irradiated females were completely sterile was 200 Gy. The present study is the first study in T. absoluta that provides the starting point for implementing the inherited sterility in this species. [ABSTRACT FROM AUTHOR]

The South American tomato pinworm, Tuta absoluta (Meyrick), is one of the major pests of tomato crop. Since its detection in the Mediterranean basin, it has been commonly controlled using chemical insecticides. However, inoculation and conservation of predatory mirids, integrated with sprays of selective insecticides, has been demonstrated to be a cost-effective strategy for controlling this pest. In this work, we tested the efficacy of two sulphur formulations, dustable and wettable powder, for controlling T. absoluta on tomato under greenhouse and open-field conditions. In addition, the side effects of both sulphur formulations on the predator, Nesidiocoris tenuis (Reuter), were evaluated under laboratory conditions. Dustable sulphur, applied weekly on tomato seedlings artificially infested with T. absoluta in greenhouse conditions, significantly reduced the infestation levels and was demonstrated to have a repellent effect on oviposition. Wettable sulphur was not effective for controlling T. absoluta populations in both greenhouse and open-field experiments. In the side effect trials conducted with N. tenuis, only dustable sulphur resulted in being moderately harmful as a fresh residue and slightly harmful as a 7-day-old residue; no effects were recorded exposing the predator to 14-day-old sulphur residues. In contrast, wettable sulphur was classified as harmless to N. tenuis. Our results suggest that the use of sulphur, especially as dustable powder, could be considered as a tool in T. absoluta management strategies, although its side effects on N. tenuis should be taken into account. The implications of these results for the use of sulphur formulations in pest and disease management programmes in tomato crops are discussed. [ABSTRACT FROM AUTHOR]

Zingiberene (ZGB) and acylsugars (AS) are allelochemicals responsible for high levels of arthropod resistance found in Solanum habrochaites (= Lycopersicon hirsutum) var. hirsutum 'PI 127826' and S. (= L.) pennelli 'LA 716', respectively. These accessions were used to develop commercial lines with good levels of pest resistance. The objective of the present work was to assess the ZGB and AS contents and the levels of resistance to Tuta absoluta in tomato hybrids between high ZGB × high AS lines, as compared with their parental lines and with commercial checks. High AS homozygous lines [TOM-688 and TOM-689, both originated from the interspecific cross S. lycopersicum (= L. esculentum) × S. pennelli], high ZGB homozygous lines (ZGB-703 and ZGB-704, both derived from the interspecific cross S. lycopersicum × S. habrochaites var. hirsutum), double heterozygotes for both ZGB and AS, single heterozygotes for ZGB, and single heterozygotes for AS were assessed for AS and ZGB contents. Low-ZGB low-AS checks 'Débora Max' and 'TOM-684' were used, as well as checks with high ZGB (PI 127826) and high AS (LA 716). The genotypes were submitted to infestation with South American tomato pinworm adults in a screenhouse, and oviposition counts were taken 10 days after the initial infestation date. Plants were scored for overall plant damage and percent leaflets attacked up to the 38th day after infestation. Genotypes heterozygous for ZGB or AS showed allelochemical contents intermediate to those of their high and low content parents, indicating incompletely dominant gene action for contents of each of the allelochemicals. There were no significant differences in T. absoluta oviposition between high-AS homozygous genotypes, high-ZGB homozygotes, single heterozygotes for AS, single heterozygotes for ZGB and double heterozygotes for ZGB and AS, but all these genotypes showed egg counts significantly lower than the low-ZGB low-AS checks. Feeding damage of T. absoluta was higher in the low-ZGB low-AS checks than in any other ZGB-rich or AS-rich tomato genotype. Relative to ZGB or AS single heterozygotes, the heterozygotes for both ZGB and AS showed higher levels of resistance to the insect, as measured by overall plant damage, indicating a synergic effect of the allelochemicals on resistance. [ABSTRACT FROM AUTHOR]

The Lycopersicon hirsutum var. hirsutum accession PI 127826 is recognized as a good source of resistance to arthropod pests due to the action of the allelochemical zimgiberene, a sesquiterpene present in its glandular trichomes. Five genotypes were selected from the F2 generation of the interspecific cross Lycopersicon esculentum `TOM-556' $\backslash times$ Lycopersicon hirsutum var. hirsutum `PI 127826', based on their low levels (BPX-368-clone#56) or high levels (BPX-368-clone#92, BPX-368-clone#105, BPX-368-clone#179, BPX-368-clone#250) of zingiberene. The five F2 genotypes were tested for resistance to the South American tomato pinworm Tuta absoluta along with accession L. esculentum `TOM-556' (pinworm susceptible), and the accessions L. hirsutum var. hirsutum `PI 127826' and L. pennellii `LA 716' (resistant). The F2 clones selected for high foliar zingiberene levels showed lower scores for leaflet lesion type (LLT), percent leaflets attacked (PLA) and overall plant damage (OPD) than the low zingiberene genotypes. The results indicated that zingiberene mediates resistance to the South American pinworm, based on feeding and on ovipositing deterrence, in populations derived from the interspecific cross between Lycopersicon. esculentum and Lycopersicon hirsutum var. hirsutum. Indirect selection for high foliar zingiberene content is suggested as an efficient technique for breeding tomatoes for resistance to the South American tomato pinworm. [ABSTRACT FROM AUTHOR]

• Biological parameters of three Argentinian populations of Pseudapanteles dignus were assessed under different temperatures. • All P. dignus populations showed dense independent parasitism under various temperature regimes. • Except for one population at 30 °C, parasitoid sex ratios did not deviate from 1: 1. • Intra and inter-population variations were revealed in pre-imaginal developmental times. • Results are useful for enhancing augmentative biological control of Tuta absoluta. Understanding important aspects of the adaptation of a biological control agent population to different abiotic conditions (e.g., temperature) is essential to ensure its success once it is released in the field. In this context, we assessed different biological parameters of three Argentinian populations of Pseudapanteles dignus (from Salta, Buenos Aires and Río Negro provinces), a larval endoparasitoid of the South American tomato pinworm, Tuta absoluta , a key pest of tomato crops worldwide, under various regimes of temperature (25, 28 and 30 °C). All local populations of P. dignus showed density-independent parasitism at the temperatures tested, and sex ratios did not deviate from 1:1 except for Salta population at 30 °C. Intra and inter-population comparisons revealed differences in pre-imaginal development times according to the temperature regimes. These results may be exploited to improve mass rearing of P. dignus and to implement biological control programs of T. absoluta in Argentina. [ABSTRACT FROM AUTHOR]

• Entomopathogenic nematodes can control tomato leafminer. • Relative humidity affected control by entomopathogenic nematodes. • Different nematode species performed differently, interacting with temperature. • Late instar larvae of the leafminer were easier to control. The South American tomato pinworm, Tuta absoluta (Meyrick) is one of the most serious insect pests of tomato plants. Current control strategies for T. absoluta primarily involve the use of insecticides, but increasing resistance in field populations has prompted research on alternative control measures. Biological control with entomopathogenic nematodes (EPNs) can be an alternative or one component of an Integrated Pest Management programme. In foliar application, EPNs encounter many factors that affect their survival and efficacy. This paper reports investigations into some of these factors for several EPN species; relative humidity (RH), temperature, time required by EPNs to enter a leaf and number of applications in whole leaf bioassays on tomato leaves. RH was the most important factor; EPNs efficacy and survival decreased as RH declined. Steinernema feltiae was the most effective species followed by Steinernema carpocapsae then Heterorhabditis bacteriophora. Steinernema carpocapsae survived better at low RH than S. feltiae. The two Steinernema species induced similar mortality at 25 °C, but S. feltiae was more virulent at lower temperatures (15 and 20 °C) while S. carpocapsae was more virulent at higher temperatures (30 and 35 °C). First and second instar larvae of T. absoluta required more applications compared to third and fourth instar larvae. The species of EPN used to control T. absoluta requires careful selection in relation to the temperature and relative humidity environment of the crop to maximise efficacy. [ABSTRACT FROM AUTHOR]

Oviposition and feeding of Scrobipalpuloides absoluta was studied on plants of seven different genotypes with varying 2-tridecanone (2-TD) foliage concentrations: Lycopersicon esculentum var. glabratum 'PI 134417' (= GLA), L. esculentum 'TSWV-547' (= ESC), F1 (ESC × GLA), and 4 F2 genotypes – two with high 2-TD (HI1, HI2), and two with low foliage 2-TD concentrations (LO1, LO2). GLA, HI1 and HI2 showed 2-TD concentrations above 185 × 10-1 2 moles/cm2, while ESC, LO1 and LO2 had 2-TD below 40 × 10-1 2 moles/cm2; F1 had intermediary levels of 2-TD (83,5 × 10-1 2 moles 2-TD/cm2). Ovipositioning was substantially higher in the low 2-TD than on either the high 2-TD genotypes or in the F1, especially in the upper portion of the plants. Scores for leaf lesion type (LLT), overall plant damage (OPD) and percent leaflets attacked (PLA) were substantially higher for the low 2-TD than for either the high 2-TD genotypes or the F1. The results indicate that 2-TD mediates resistance to S. absoluta in the interspecific cross, and strongly suggest that 2-TD acts as both an ovipositioning and feeding deterrent for this insect. [ABSTRACT FROM AUTHOR]

Augmentative biocontrol implemented through inoculative seasonal releases of one or more biological control agents has proven to be a reliable crop protection approach in greenhouse and open field crops. The South American tomato pinworm, Tuta absoluta , is a key tomato pest worldwide. In this context, the effectiveness of the American-native larval endoparasitoid Pseudapantales dignus in reducing T. absoluta populations, in a semi-field set-up under greenhouse crop conditions, was assessed. In individual plants enclosed in cages, five host (T. absoluta):parasitoid (P. dignus) relative densities (2:1; 4:1; 4:2; 10:3 and 10:5) were evaluated through inclusion techniques. Controls for each treatment were included. Parasitization was allowed for 48 h; then leaves with signs of moth injury were removed and taken to the laboratory for rearing the host larvae until its pupation or the formation of P. dignus cocoons. Percentages of parasitism were calculated for each treatment and compared using a generalized linear model (GLM) with binomial link function. Pseudapanteles dignus females failed to parasitize at a host density of 2 larvae per plant; meanwhile at the other host densities tested, it reached from 23 to 61% parasitism. The greater percentage of parasitism was observed at host:parasitoid relative densities of 10:3. This field experiment showed evidence that the efficiency of this biocontrol agent decreases at low host densities, probably influenced by a reduction in host localization stimuli. Besides, at higher P. dignus release rates, parasitism decreased due to self-limitation of adult females by mutual interference when searching for hosts. Pseudapantales dignus has a significant potential for use in biological control programs. Display Omitted • Tuta absoluta is a key tomato pest native to South America and invaded continents. • This study provides the first evaluation of the effectiveness of the endoparasitod Pseudapanteles dignus on greenhouse tomato. • We assessed five host:parasitoid densities per plant through inoculative releases, yielding the better performance of a 10:3 host:parasitoid relative density. • Lesser stimuli from hosts at lower T. absoluta densities and mutual interference of searching adult females at higher P. dignus densities could affect the biocontrol exerted by this parasitoid. [ABSTRACT FROM AUTHOR]