The tomato leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a devastating pest of tomato originating from South America. After its initial detection in eastern Spain in 2006, it rapidly invaded various other European countries and spread throughout the Mediterranean basin. If no control measures are taken, then the pest can cause up to 80–100% yield losses in tomato crops in recently invaded areas and may pose a threat to both greenhouse and open-field tomato production. The exceptional speed and extent of T. absoluta invasion have called for studies documenting its biology and ecology, while indicating an urgent need for efficient and sustainable management methods. The development of approaches to manage T. absoluta would be facilitated through a detailed revision of information on this pest in its area of origin. This review combines information on the invasion by T. absoluta, its ecology, and potential management strategies, including data that may help the implementation of efficient biological control programs. These programs, together with a variety of other management tactics, may allow efficient integrated pest management of T. absoluta in Europe and Mediterranean Basin countries.

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Biological invasion of European tomato crops by Tuta absoluta: ecology, geographic expansion and prospects for biological control

Fungal endophytes are ubiquitous fungi that inhabit healthy plant tissues without causing disease. Endophytes have been found in every plant species examined to date and may be important, but often overlooked, components of fungal biodiversity. In two sites in a lowland, moist tropical forest of central Panama, we quantified endophyte colonization patterns, richness, host preference, and spatial variation in healthy leaves of two co-occurring, understory tree species [Heisteria concinna (Olacaceae) and Ouratea lucens (Ochnaceae)]. From 83 leaves, all of which were colonized by endophytes, we isolated 418 endophyte morphospecies (estimated 347 genetically distinct taxa), most of which were represented by only a single isolate (59%). Among morphospecies encountered in more than one leaf (nonsingletons), we found evidence of host preference and spatial heterogeneity using both morphospecies frequencies and presence/absence records. Based on these data, we postulate that tropical endophytes themselves may be hyperdiverse and suggest that extrapolative estimates that exclude them will markedly underestimate fungal species diversity.

Are tropical fungal endophytes hyperdiverse

Neonate Lepidoptera are confronted with the daunting task of establishing themselves on a food plant. The factors relevant to this process need to be considered at spatial and temporal scales relevant to the larva and not the investigator. Neonates have to cope with an array of plant surface characters as well as internal characters once the integument is ruptured. These characters, as well as microclimatic conditions, vary within and between plant modules and interact with larval feeding requirements, strongly affecting movement behavior, which may be extensive even for such small organisms. In addition to these factors, there is an array of predators, pathogens, and parasitoids with which first instars must contend. Not surprisingly, mortality in neonates is high but can vary widely. Experimental and manipulative studies, as well as detailed observations of the animal, are vital if the subtle interaction of factors responsible for this high and variable mortality are to be understood. These studies are essential for an understanding of theories linking female oviposition behavior with larval survival, plant defense theory, and population dynamics, as well as modern crop resistance breeding programs.

Ecology and behavior of first instar larval lepidoptera

1 Control failures of insecticides used against the tomato leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in Brazil led to the investigation of the possible occurrence of resistance of this insect pest to abamectin, cartap, methamidophos and permethrin.

2 The insect populations were collected from seven sites in the states of Minas Gerais, Rio de Janeiro, and Sao Paulo. These populations were subjected to concentration–mortality bioassays using insecticide-impregnated filter papers.

3 We were unable to obtain a single population which provided a susceptibility standard for all insecticides tested. Therefore, the resistance levels were estimated in relation to the most susceptible population to each insecticide. Resistance to abamectin and cartap were observed in all populations when compared with the susceptible standard population, with resistance ratios ranging from 5.2- to 9.4-fold and from 2.2- to 21.9-fold for abamectin and cartap, respectively. Resistance to permethrin was observed in five populations with resistance ratios ranging from 1.9- to 6.6-fold, whereas resistance to methamidophos was observed in four populations with resistance ratios ranging from 2.6- to 4.2-fold.

4 The long period and high frequency of use of these insecticides against this insect pest suggest that the evolution of insecticide resistance on them has been relatively slow. Alternatively, the phenomenon might be widespread among Brazilian populations of T. absoluta making the finding of suitable standard susceptible populations difficult and leading to an underestimation of the insecticide resistance levels in this pest.

5 Higher levels of resistance to abamectin, cartap and permethrin are correlated with greater use of these compounds by growers. This finding suggests that local variation in insecticide use was an important cause of variation in susceptibility.

Insecticide resistance in populations of Tuta absoluta (Lepidoptera: Gelechiidae)

BACKGROUND: Insecticide resistance is a likely cause of field control failures of Tuta absoluta, but the subject has been little studied. Therefore, resistance to ten insecticides was surveyed in seven representative field populations of this species. The likelihood of control failures was assessed, as well as weather influence and the spatial dependence of insecticide resistance.

RESULTS: No resistance or only low resistance levels were observed for pyrethroids (bifenthrin and permethrin), abamectin, spinosad, Bacillus thuringiensis and the mixture deltamethrin + triazophos (<12.5-fold). In contrast, indoxacarb exhibited moderate levels of resistance (up to 27.5-fold), and chitin synthesis inhibitors exhibited moderate to high levels of resistance (up to 222.3-fold). Evidence of control failures was obtained for bifenthrin, permethrin, diflubenzuron, teflubenzuron, triflumuron and B. thuringiensis. Weather conditions favour resistance to some insecticides, and spatial dependence was observed only for bifenthrin and permethrin.

CONCLUSION: Insecticide resistance in field populations of the tomato pinworm prevails for the insecticides nowadays most frequently used against them—the chitin synthesis inhibitors (diflubenzuron, triflumuron and teflubenzuron). Local selection favoured by weather conditions and dispersal seem important for pyrethroid resistance evolution among Brazilian populations of T. absoluta and should be considered in designing pest management programmes. Copyright © 2011 Society of Chemical Industry

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Control failure likelihood and spatial dependence of insecticide resistance in the tomato pinworm, Tuta absoluta

An ecological life table was constructed, aiming to determine the critical stages and key mortality factors of Tuta absoluta (Lepidoptera: Gelechiidae). The total population mortality of this tomato leafminer was 92.3%. During the egg stage the mortality was 58.7%, mainly due to egg inviability. A total of 8.6% egg parasitism by Trichogramma pretiosum (Riley) (Hymenoptera: Trichogrammatidae) and 5.0% egg predation by Xylocoris sp. (Heteroptera: Anthocoridae), Cycloneda sanguinea (L.) (Coleoptera: Coccinellidae) and members of the family Phlaeothripidae (Thysanoptera) was observed. The mortality of the larval stage was 33.0%. This was considered to be the critical stage as it showed the highest apparent mortality (79.8%). Larval parasitism was low (0.1%), and was only found with Goniozus nigrifemur Ashmead (Hymenoptera: Bethylidae). Predators were responsible for 79.4% of larval mortality. Therefore, their attraction to and maintenance in the target area are important management tactics to be considered fo...

Ecological Life Table of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)

The objective of this work was to evaluate the impact of integrated pest management (IPM) in the productivity of the tomato and in the populations of leafminers, fruit borers, and natural enemies in tomato crops. The treatments were calendar (spraying twice weekly with insecticides and fungicides), IPM (spraying when action thresholds were achieved), and control (no pesticide was applied). IPM was the most efficient system of pest control due to presenting similar productivity and 65.6% less pesticide applications than in the calendar. The attack of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) and Liriomyza spp. (Diptera: Agromyzidae) to the leaves only achieved the action threshold in the final phase of the cultivation. The main fruit borer was Neoleucinoides elegantalis (Guen.) (Lepidoptera: Crambidae), followed by T. absoluta and Spodoptera eridania (Cr.) (Lepidoptera: Noctuidae). The natural enemy populations were severely reduced by excessive pesticide applications. Predators were more abundant than parasitoids. The most abundant predators were Araneidae, Anthicus sp. (Coleoptera: Anthicidae), Cycloneda sanguinea larva (L.) (Coleoptera: Coccinellidae), Staphylinidae adults (Coleoptera), Orius sp. and Xylocoris sp. (Hemiptera: Anthocoridae), Formicidae (Hymenoptera), and Phlaeothripidae (Thysanoptera). The most abundant parasitoids were Hymenoptera of the families Eulophidae, Braconidae (Bracon sp. and Chelonus sp.), Trichogrammatidae [Trichogramma pretiosum (Riley)] and Bethylidae (Goniozus nigrifemur Ashmead), besides Tachinidae (Diptera).

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Impact of integrated pest management on the population of leafminers, fruit borers, and natural enemies in tomato

Effect of plantation age on diversity and population fluctuation of Lepidoptera collected in Eucalyptus plantations in brazil

Sampling and non-action levels for predators and parasitoids of virus vectors and leaf miners of tomato in Brazil

This work aimed to study the selectivity of the insecticides carbaryl, deltamethrin, methyl parathion, permethrin and trichlorfon in favor of the predator Doru luteipes (Scudder) (Dermaptera: Forficulidae) and of the parasitoid Cotesia sp. (Hymenoptera; Braconidae) in relation to the control of the kale leafworm Ascia monuste orseis (Godart) (Lepidoptera: Pieridae). LC90 were determined for A. monuste orseis, and these were used as discriminatory doses to evaluate the degree of selectivity of the insecticides. Deltamethrin and permethrin were highly selective in favor of D. luteipes. Deltamethrin was intermediate selectivity in favor of Cotesia sp., while permethrin was not selective in favor of this parasitoid. Trichlorfon was highly selective in favor of fourth instar nymphs and adults of D. luteipes, and it was intermediate selectivity in favor of Cotesia sp. and first instar nymphs of the predator. Carbaryl was intermediate selectivity in favor of Cotesia sp., but it did not show selectivity in favor of D. luteipes. Methyl parathion did not show selectivity in favor of D. luteipes and Cotesia sp. Adults of D. luteipes were less sensitive to deltamethrin, permethrin and trichlorfon than adults of Cotesia sp. and the inverse happened with carbaryl. Both natural enemies presented high sensibility to methyl parathion. Fourth instar nymphs of and adults of D. luteipes were more sensitive to methyl parathion and trichlorfon than first instar nymphs. Both nymphs and adults of D. luteipes presented similar sensibility to the carbaryl, deltamethrin and permethrin.

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Seletividade de inseticidas a Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) e Cotesia sp. (Hymenoptera: Braconidae) inimigos naturais de Ascia monuste orseis (Godart, 1818) (Lepdoptera: Pieridae)

Moacyr Mascarenhas Motta Miranda

Papers

Ecological Life Table of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)

Impact of integrated pest management on the population of leafminers, fruit borers, and natural enemies in tomato

Effect of plantation age on diversity and population fluctuation of Lepidoptera collected in Eucalyptus plantations in brazil

Sampling and non-action levels for predators and parasitoids of virus vectors and leaf miners of tomato in Brazil

Seletividade de inseticidas a Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) e Cotesia sp. (Hymenoptera: Braconidae) inimigos naturais de Ascia monuste orseis (Godart, 1818) (Lepdoptera: Pieridae)