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Nesidiocoris tenuis (Reuter) originated in tropical regions but has distended its range and is now common around the world. Even though, it is a zoophytophagous both adults and nymphs predate upon a broad range of insect hosts. It makes a significant contribution in tomato IPM program by feeding on whiteflies, spider mites, caterpillars and leaf miners. In the present study, we employed CLIMEX 4.0 software to predict and assess the effect of environmental factors on the global distribution of N. tenuis by using the ‘Compare Locations’ function. Based on the CLIMEX prediction, a large part of Eastern Europe, major parts of South America, Central and Southern Africa, South Asia and Coastal Australia were highly suitable for the long-term survival of N. tenuis. The model output on global prediction maps indicates that cold and dry stress may restrict N. tenuis distribution in various places. However, cold stress appears to be the major limiting factor. This study highlighted an efficient way to construct a habitat suitability map for N. tenuis, potentially useful in the release of target species in new locations. The model may also be used to determine the release time of N. tenuis based on the favourable growth index period. [ABSTRACT FROM AUTHOR]

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Simple Summary: The predatory insects Macrolophus pygmaeus Ramber (Heteroptera: Miridae) and Nesidiocoris tenuis Reuter (Heteroptera: Miridae) are important biological control agents used commercially for the control of main pests in greenhouses, such as Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) and whiteflies (Homoptera: Aleyrodidae). In this study, we investigated the predation efficacy of young and old females and males of the two mirid bugs, M. pygmaeus and N. tenuis, when feeding on eggs of T. absoluta on tomato leaves. Young females of M. pygmaeus exhibited a higher predation efficiency compared to old ones, whereas males displayed a consistently low efficiency of predation irrespective of their age. Both young females and males of N. tenuis displayed a similarly high predation efficiency, although the old females exhibited a higher efficiency of predation compared to their male counterparts, but lower than the efficacy of the M. pygmaeus individuals. Our findings indicate that the two predatory species have different functional response characteristics to their prey depending mainly on their sex and age which may influence their efficacy as biological control agents. The predatory mirids Macrolophus pygmaeus Ramber (Heteroptera: Miridae) and Nesidiocoris tenuis Reuter (Heteroptera: Miridae) are used for the biological control of Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) and other pests in tomato greenhouses. The functional response of 1-day-old (young) and 10-day-old (old) adult females and males of M. pygmaeus and N. tenuis on eggs of T. absoluta was determined on tomato at two temperatures (20 °C and 25 °C) and LD 16:8. Females of M. pygmaeus exhibited higher predation efficiency than males at both tested temperatures. Young M. pygmaeus females had a higher efficiency than old ones, whereas males had a low efficiency irrespective of age. The predation efficiency of N. tenuis was high (but lower than M. pygmaeus) in both young females and males, although old females had a higher efficiency than the respective males. Our results show that the two predatory species have different functional response characteristics to their prey depending mainly on sex and age, which may affect their role as biological control agents. [ABSTRACT FROM AUTHOR]

Herbivore-induced plant organic volatiles (HIPVs) have recently been studied to improve biological pest control. In contrast, the effects of volatile organic compounds (VOCs) that are not induced by herbivory (non-HIPVs) have received less attention. The latter are essential in the first stages of crop colonization by entomophagous insects (predators and parasitoids) used in biological pest control programs. Furthermore, the effects on entomophagous insects of different cultivars of a cultivated botanical species have not been studied. The aim of this work was to study the different non-HIPVs found in 10 tomato cultivars used in tomato greenhouses on two entomophages: the egg parasitoid Trichogramma achaeae (Hymenoptera, Trichogrammatidae) and the zoo-phytophagous predator Nesidiocoris tenuis (Hemiptera, Miridae). The results indicate that although there is considerable quantitative and qualitative variation in the emission of VOCs in the 10 tomato cultivars analysed, this variability made it difficult to determine the influence of the volatiles on the attraction of the predatory species N. tenuis, with only one cultivar (Rebelion) exhibiting a significantly higher attractiveness than the rest of the cultivars. For the parasitoid T. achaeae, these same volatiles had a significant effect (in part) on parasitoid behaviour. However, this attraction was not reflected in the discriminant analysis, at least for the volatiles analysed. The analysis showed four groups of well-differentiated cultivars, according to the non-HIPV composition, and this bore no relation to the levels of attractiveness registered in the different cultivars, with the exception again of the Rebelion cultivar, which seems not to be very attractive for the parasitoid and its parasitism activity. The implications of non-herbivore-induced (non-HPV) VOCs in the biological control of greenhouse pest species are described and discussed. [ABSTRACT FROM AUTHOR]

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

In this study, the effect of exposing the adult stages of the predator Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) to cold temperatures at different times was examined. In the experiments, individuals that reached the adult stage on the same day were kept in the dark for 5, 10, and 15 days at 7, 10, and 15°C. Adults kept at low temperatures were fed three times per week with Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs and honey water. Individuals of N. tenuis that survived after cold exposure were reared at 25°C under a 16:8 (L:D) day-night cycle. The lowest adult survival rate after cold exposure was 65.00% when held at 7°C for 15 days. The highest survival rates were 94.00% and 98.00% when stored at 7 and 10°C, respectively, for 5 days. The most extended longevity in individuals reared following cold exposure was 14.06 days at 7°C and 14.94 days at 10°C, respectively, while the shortest lifespan was 8.10 days in adults held at 15°C for 15 days. The average number of nymphs produced by adults kept at 7°C for 15 days was 322.4, while the number produced by adults kept at 15°C for 15 days was 47.6. Except for the nymphs acquired from adults held at 15°C for 15 days, the number of nymphs obtained from adults stored at other temperatures and durations did not differ statistically from the control group. The study concludes that those who intend to mass-produce N. tenuis adults should store them at temperatures between 7 and 10°C for up to 10 days. [ABSTRACT FROM AUTHOR]

We studied plant–plant communication in a system that included eggplants, herbivores as prey, and the omnivorous mirid Nesidiocoris tenuis. When uninfested eggplants were exposed to volatiles from conspecific plants infested by N. tenuis adults, the amounts of jasmonic acid (JA) and salicylic acid (SA) in the exposed plants remained to be similar to those in uninfested eggplants that were exposed to volatiles from uninfested conspecific plants (control eggplants). Subsequent artificial damage to the leaves of either the exposed or control eggplants using scissors led to a significant increase in JA content in the leaves. Furthermore, following the damage, the JA content in the exposed plants was significantly higher than in the control plants. In contrast, the amount of SA in the eggplants was not affected by either exposure or subsequent artificial damage. The fecundity of Kanzawa spider mites on the leaf disks of the exposed plants was significantly lower than that on the leaf disks of the control plants. The weight gain of 2nd stadium Spodoptera litura larvae on the exposed plants was significantly lower than on the control plants. However, the survival and fecundity of N. tenuis females on both exposed and control plants were not significantly different. This study demonstrates the potential variations in the tolerance of herbivorous and omnivorous arthropods to plant defenses in response to exposure to plant volatiles. [ABSTRACT FROM AUTHOR]

Effective management of tomato pests such as Bemisia tabaci and Tuta absoluta requires the integration of more sustainable control methods. Applying integrated pest management (IPM) approaches using combinations of biocontrol agents with agronomic practices such as the modulation of fertilisation offers opportunities toward more efficient pest control, all the more so since the underlying bottom-up and top-down regulations are interdependent. We investigated the relative influence of the bottom-up effects of reduced fertilisation (by 47%) and the use of the mirid predators Dyciphus errans or Macrolophus pygmaeus in combination with Nesidiocoris tenuis on the control of B. tabaci and T. absoluta. Densities of B. tabaci and T. absoluta population decreased more rapidly when fertilisation was reduced. The presence of D. errans caused reduction in N. tenuis densities and in the number of necrotic rings caused by N. tenuis. The negative effects of bottom-up forces triggered by reduced fertilisation on B. tabaci, T. absoluta and N. tenuis populations and damage were greater in the presence of D. errans. Our study shows that interactions between predators and fertilisation management are important in agro-ecosystems and should be considered in the development of sustainable IPM strategies. [ABSTRACT FROM AUTHOR]

Abstract Tuta absoluta and Bemisia tabaci are two key worldwide tomato pests. In response to chemical control limits, the use of zoophytophagous mirid predators as biocontrol agents is being increasingly studied and proposed for the management of these pests. However, the use of some mirid species and in particular Nesidiocoris tenuis, which naturally occurs in European tomato crops, is controversial due to its ability to inflict significant damage on tomato plants (necrotic rings) in parallel of its high predation capacity. Combining other mirid species such as Macrolophus pygmaeus and Dicyphus errans with N. tenuis could reduce the population growth of T. absoluta and of B. tabaci, while maintaining N. tenuis populations below a critical crop damage threshold. In this study, we tested the effect of combining N. tenuis with M. pygmaeus (at two densities: 10 and 15 individuals per plant) and with or without D. errans (five individuals per plant) on the abundance of all insects (predators and pests) for 8 weeks. We also measured leaf damage by T. absoluta and plant and flower damage (necrotic rings, flower abortion rate) by N. tenuis. We found that the combined presence of D. errans, M. pygmaeus and N. tenuis rapidly and significantly reduced the densities of B. tabaci adults, and T. absoluta larvae and damage compared to when M. pygmaeus (with both densities) was only present with N. tenuis. The presence of D. errans was critical to reduce N. tenuis population growth and necrotic rings on tomato plants, while higher densities of M. pygmaeus density reduced the rate of aborted flowers by N. tenuis. The manipulation of M. pygmaeus densities added to the presence of D. errans could provide a sustainable solution to control multiple pests simultaneously while reducing the damaging phytophagous activity of N. tenuis in tomato crops.

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

Tomatoes are an important vegetable crop in different parts of the world, where they are grown year-round. Currently, the most important problem facing tomato growers in the world is the devastating damage caused by the invasive tomato leaf miner, Tuta absoluta Meyrick (Gelechiidae: Lepidoptera). In this study, the efficacy of three bioinsecticides (Bacillus thuringiensis formulations, spinosad and emamectin benzoate, and two chemical insecticides (indoxacarb and chlorpyrifos) against T. absoluta and their adverse effects on predators were conducted in two different governorates in Egypt, based on recommended doses of the tested insecticides. In addition, the residue dissipation of the tested insecticides was determined in tomato fruits. Results indicated that emamectin benzoate was the most effective insecticide, exhibiting the highest reduction in T. absoluta density of 78.05 and 87.11% in Giza and Qualybia governorates, respectively, followed by indoxacarb (77.01%) in Giza and spinosad (80.44%) in Qualybia. In addition, our finding proved that the tested biopesticide formulations, especially Bt formulations, are environmentally friendly to two of the most important predators in tomato cultivation: Nesidiocoris tenuis and Macrolophus pygmaeus Reuter. Moreover, the analysis of insecticide residues on tomato fruits revealed that bioinsecticide residues dissipated faster than conventional insecticide (chlorpyrifos). The results of this research suggested that bioinsecticides could be used for the management of T. absoluta under field conditions. [ABSTRACT FROM AUTHOR]

Extreme climatic events, including heat waves with high‐temperature peaks during the day, are expected to occur more often in many parts of the world due to climate change and may exert negative effects on existing biological control strategies. To assess the effects of high‐temperature peaks on two commonly used, and naturally co‐occurring mirid predators, adults and nymphs of Nesidiocoris tenuis and Macrolophus pygmaeus were exposed either to constant 25°C or daily mean temperatures of 25°C with cycles rising up to 30 or 40°C. Preferred location of the two mirid species on different strata of tomato plants was investigated when they were exposed to the different temperature regimens alone or combined. Activity of mirids under the different temperature regimens was continuously monitored for 48 h using a Drosophila Activity Monitor system. Finally, the efficacy of the mirids preying on Tuta absoluta eggs was measured at the different temperature regimens in a Petri dish assay. Heat waves reaching 30 and 40°C in some instances affected the location of the mirids either when they were on the plant alone or under competition conditions. Locomotory activity of M. pygmaeus in the 40°C treatment was strongly reduced, whereas it remained high in N. tenuis. Effects of temperature peaks on prey consumption were visible in M. pygmaeus nymphs, N. tenuis females and males of both species. We suggest that the different responses of the two species to high‐temperature peaks may reduce their competition and support sustained control when both species are present simultaneously. Moreover, both species were found to be less susceptible to heat peaks when compared to previously reported results for their prey T. absoluta. [ABSTRACT FROM AUTHOR]

Mirid predators are increasingly used in biological control of multiple greenhouse crops pests. However, due to great morphological similarity and tiny body size, some mirid predators have been largely confused with their allied species. Nesidiocoris tenuis Reuter as a commercial mirid predator was confused largely with Nesidiocoris poppiusi Carvalho in China.To evaluate the biocontrol potential of N. poppiusi, its biological traits and the functional response to Bemisia tabaci Gennadius were studied compared with N. tenuis under laboratory conditions.The results showed that no significant differences of the developmental times from the first instar to adult stages between the 2 mirids fed on Corcyra cephalonica Stainton eggs were observed, while N. poppiusi had better population growth parameters than N. tenuis. Under the condition with prey, both female and male of N. poppiusi lived significantly longer than those of N. tenuis. It could lay 74.0 eggs, which was significantly higher than that of N. tenuis (30.2 eggs). Under the condition without prey, both N. poppiusi and N. tenuis couldn't complete development to adulthood on tomato, tobacco, muskmelon, and cabbage leaves, however, tobacco and tomato were more suitable than the other 2 plants. A type II functional response was observed for both males and females of the 2 predators. Nesidiocoris poppiusi females consumed significantly more B. tabaci pupae than N. tenuis when prey densities were large than 30. Our results indicated that N. poppiusi could be a promising candidate for biological control of B. tabaci. Graphical Abstract [ABSTRACT FROM AUTHOR]

Population of whiteflies and its natural enemy Nesidiocoris tenuis were recorded for the period of three years and averages were computed and subjected to simple correlation by considering weather parameters as the dependent variable. During observed years, population of whiteflies peakranged within 33rd to 37th SMW, the mean occurrence of the N. tenuis started with the build-up of its prey population and peaked at 40th SMW, declined thereafter and the populationof whiteflies had significantly positively correlated with maximum temperature, minimum temperature, evening relative humidity, and wind speed, respectively. Rainfall had a positive correlation but was not significant. In the present study, the population of N. tenuis was dependent only on the prey density but not on the weather parameters. The established model validated satisfactorily(R2=0.75; RMSE = 2.05). [ABSTRACT FROM AUTHOR]

Recent studies have suggested that predatory mirid bugs may be an effective alternative for controlling aphids in sweet pepper greenhouses. This study examined the effect of three constant temperatures (18, 24, and 30 °C) on the life history traits of predatory mirid species Nesidiocoris tenuis, Macrolophus pygmaeus, and Dicyphus bolivari, preying on the aphid Myzus persicae nicotianae in sweet pepper plants. As the temperature increased, the survival rate decreased for M. pygmaeus and D. bolivari, while for N. tenuis, it was the opposite, and their survival increased. When considering all the biological traits studied together, the estimated intrinsic rate of increase (rm) decreased as the temperature increased for M. pygmaeus and D. bolivari. In contrast, the rate increased as the temperature increased for N. tenuis. These results suggest that M. pygmaeus and D. bolivari are better adapted to lower temperatures than N. tenuis, which is more adapted to warm temperatures. The implications of these results for improving the biological control of aphids in sweet pepper greenhouses through the use of mirid bugs are discussed in relation to different temperature regimes. [ABSTRACT FROM AUTHOR]

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

Plant essential oils (PEOs) are being studied as a potential alternative to synthetic pesticides in agriculture. PEOs have the potential to control pests both directly, by being toxic or repellent to pests, and indirectly, by activating plant's defense mechanisms. In this study, the effectiveness of five PEOs (Achillea millefolium, Allium sativum, Rosmarinus officinallis, Tagetes minuta, and Thymus zygis) on controlling Tuta absoluta and their impact on the predator Nesidiocoris tenuis was examined. The study revelead that PEOs from A. millefolium and A. sativum-sprayed plants significantly reduced the number of T. absoluta-infested leaflets and did not affect the establishment and reproduction of N. tenuis. Additionally, the spraying of A. millefolium and A. sativum increased the expression of defense genes in the plants, triggering the release of herbivory-induced plant volatiles (HIPVs), such as C6 green leaf volatiles, monoterpenes, and aldehydes, which can be messengers in tritrophic interactions. The results suggest that PEOs from A. millefolium and A. sativum can provide a dual benefit for controlling arthropod pests, as they can directly exhibit toxicity against these pests while also activating plant defense mechanisms. Overall, this study provides new insights into using PEOs as a sustainable solution for controlling pests and diseases in agriculture, by reducing synthetic pesticides and promoting the use of natural predators. [ABSTRACT FROM AUTHOR]

The tomato pinworm damage, population build-up, the damage and longevity of native predatory bug, Nesidiocoris tenuis in sole crop and diversified crop of tomato (pumpkin and sunn hemp as border crop + a patch of sunn hemp as hedgerow) were studied. Infesta- tion of tomato pinworm, Phthorimaea absoluta was found to be the highest in the sole crop (5.60 live mines/plant at 20 DAP) compared to the diversified crop of tomato (1.50 live mines per plant). No significant difference in the number of necrotic rings per plant was observed between the sole crop and the diversified crop of tomatoes. The development period of nymphs of N. tenuis was the shortest in tomatoes followed by pumpkin. The results of the present study confirmed the role of crop diversification in supporting the population build-up of predatory bug N. tenuis in effecting the biological control of pinworm in tomato crop. [ABSTRACT FROM AUTHOR]

Tuta absoluta (Lepidoptera: Gelechiidae) is a worldwide invasive insect species, considered a major pest of tomato. It has recently established in Burkina Faso, where chemical control remains the only affordable option to limit damages. Nesidiocoris tenuis (Hemiptera: Miridae) is commercialized as a biological agent to control this pest in other parts of the world. But very limited information exists on this predator in Burkina Faso. In this study, we first performed an insect survey in all agricultural regions areas of the country, and we found N. tenuis to be widely observed in all of them. Then, we performed two laboratory bioassays and demonstrated that all instars preyed on T. absoluta eggs, whether they were fed ad libitum or they had to actively forage for their prey. Because insecticide tolerant populations of T. absoluta were recently identified, we finally aimed at identifying agrochemicals that do not harm N. tenuis. We evaluated the toxicity of two synthetic insecticides, three bio‐bacterial insecticides and eight plant extracts, all being active ingredients available on the local market. Most of them (i.e., abamectin, emamectin benzoate, spinosad, spinetoram) were highly toxic for both T. absoluta and N. tenuis. In contrast, Bacillus thuringiensis var. Kurstaki, neem oil, Cleome viscosa (Asian spiderflower), Ocimum basilicum (Basil) and Cassia occidentalis (Coffee senna) were compatible with N. tenuis while still controlling T. absoluta. Based on our results, we recommend the application of Bacillus thuringiensis to both control T. absoluta and which does not compromise the maintenance of N. tenuis populations. [ABSTRACT FROM AUTHOR]

The predation rate and prey-stage preference of two mirid predatory bugs Macrolophus pygmaeus Rambur and Nesidiocoris tenuis (Reuter) (Hemiptera Miridae), were investigated on the diamondback moth (DBM) Plutella xylostella (L.) (Lepidoptera Plutellidae), a noxious pest of cruciferous plants. In particular, predation capacity of each predatory stages of both predators was studied on the first, second and third larval instars of DBM. There were no significant differences in predation between the predators on eggs, second and third instar larvae of DBM. Among the different life stages of both predators, females had the highest predation on eggs and all larval instars of DBM. Preference indices for both mirid species indicated that there was a preference toward eggs, first instar and second instar larvae versus first instar, second instar and third instar larvae, respectively. The data of the current study suggest that M. pygmaeus and N. tenuis are effective predators of DBM particularly against eggs and first instar larva. It would therefore be worth to investigate how these mirids can be incorporated in biological control programs of DBM. [ABSTRACT FROM AUTHOR]

Mirid bug has become challenging pest infesting bottle gourd crop at Haryana state and Delhi NCR region in India. The feeding punctures caused on fruits due to bugs appears to be light reddish brown spots/blister, leading to blemished fruits which often fail to fetch a good market price. In the present study, we have endowed the species diagnosis (morphological and molecular), population dynamics, biology, fruit damage intensity and ecofriendly management of mirid bugs in bottle gourd crop. From the morphological studies it was found that, the mirid bug so investigated was found to be the zoophytophagous plant bug, Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae). In addition, the molecular analysis (DNA Barcoding) also confirmed the species identity with the DNA sequence generated (Accession No. OM117590) matching up to 99.86% with that of the available relative sequences with a total branch length of 0.10 base substitutions per site in the phylogenetic tree. Across the fields surveyed, it was found that on an average the maximum abundance of N. tenuis was noticed at tender tip of vines (7.0 bugs per tender tip of vine) followed by fruits (4.9 bugs per fruit) and leaves (4.1 bugs per leaf). There were two peak incidence of N. tenuis noticed during the study. First peak during 21st SMW (4th week of May) (8.7 bugs per leaf and 12.7 bugs per tender tip of vine) and second peak during 24th SMW (3nd week of June) (7.3 bugs per leaf, 10.5 bugs per tender tip of vine and 5.7 bugs per fruit). During the study, it was found that the maximum temperature, mean temperature and sunshine hours showed significant positive relationship with N. tenuis population on leaves (r = 0.800, 0.560 and 0.770, respectively), tender tip of vine (r = 0.880, 0.550 and 0.780, respectively) and fruits (r = 0.801, 0.553 and 0.549, respectively). In the present investigation it was found that N. tenuis successfully completed its life cycle on bottle gourd plants with total life cycle duration of ~ 34 days. The mean fecundity was observed to be 10.8 eggs. The age-stage specific survival rate (Sxj) and life expectancy (Exj) studies revealed that the survival rate and life expectancy of adult females was higher than that of adult males of N. tenuis. The % fruit damage due to N. tenuis ranged between 61.90 – 73.68% and damage intensity ranged from 20.4 to 27.4 numbers of damage punctures per 2 cm2 area of fruit rind. Due to bagging of fruits, there was 67.60% reduction in fruit damage and 96.05 – 98.61% increase in number of marketable fruits which clearly envisage the farmers to adopt bagging technique in bottle gourd against N. tenuis to obtain quality fruits with higher economic yield. [ABSTRACT FROM AUTHOR]

The silverleaf whitefly (Bemisia tabaci) and the South America tomato pinworm (Tuta absoluta) are two of the most destructive pests of tomato. Open-field tomato production frequently relies on chemical treatments, which has been shown to lead to pesticide resistance. The integration of biological control using predatory mirid bugs is an effective alternative method for managing these pests. However, methods to establish and maintain populations of zoophytophagous mirids are not adequately described. We explored the potential use of two mirids naturally occurring in Florida, Nesidiocoris tenuis and Macrolophus praeclarus. We conducted 6 field experiments over 4 consecutive years to develop a strategy to maintain the mirids. Pre-plant inoculation of tomato plants did not lead to their establishment, likely due to the low prevalence of prey. We explored the use of sesame (Sesamum indicum) to retain the mirids. Intercropping sesame maintained the populations of N. tenuis throughout the duration of the crop. Macrolophus praeclarus never established in any of the open-field experiments. Nesidiocoris tenuis damage was minimal (<1 necrotic ring/plant) and mirid damage was reduced in the presence of sesame. Our results show that intercropping sesame may provide a means to utilize mirids to manage B. tabaci, an established pest, and provide options to tomato growers should T. absoluta invade USA. [ABSTRACT FROM AUTHOR]

Zoophytophagous bugs feed on both arthropod pests and plants, and can survive or reproduce solely on particular plants. This characteristic ensures their survival when released as natural enemies when the density of target pests is low. When using zoophytophagous bugs, exotic species or strains should be avoided as biological control agents due to their ecological risks. This study reviews investigations of indigenous Orius species and indigenous strains of N. tenuis and their exploitations as biological control agents in Japan. Orius strigicollis, which can reproduce under short-day conditions, is recommended for augmentative biological control in greenhouses. Orius sauteri, the predominant and most abundant species in the field, is not recommended for releases in greenhouses because it enters diapause under short-day conditions. However, this species can be used for conservation biological control in the field, where the bug can be preserved through the use of selective pesticides or by conserving companion plants. Violet light illumination is a promising tool to manipulate the movement of this species in the field. Nesidiocoris tenuis occurs only in the southern region of Japan, and its density in the field is low. This bug can be used for augmentative biological control in greenhouses. It can reproduce on specific plants, including Sesamum indicum, Cleome hassleriana, Verbena × hybrida, and Scaevola aemula. These plants can be used as banker plants to improve the establishment and reproduction of N. tenuis in greenhouses. Indigenous Orius species and Nesidiocoris tenuis are promising biological control agents in Japan. [ABSTRACT FROM AUTHOR]

With the invasion or local occurrence of Bemisia tabaci and Tuta absoluta in recent decades, they both have become two major insect pests of tomato crops in many countries. The biological control of these two pests through heteropteran predators, e.g., Nesidiocoris tenuis or Macrolophus pygmaeus, is a key pest management strategy. However, by contrast to M. pygmaeus, N. tenuis could usually cause plant damage and yield loss. The joint use of these two mirids for pest management has not been described yet, although it may be helpful in reducing the side effects of N. tenuis on crop (owing to competitive and/or agonistic interactions between the two species). In this study, we compared the abundance of predators and pests in treatments with N. tenuis and M. pygmaeus together versus N. tenuis alone and in the presence of B. tabaci only or B. tabaci and T. absoluta. We also measured necrotic rings and tomato flower production in these four treatments. We found that the joint use of both mirid predators together led to (1) a reduced overall mirid density and (2) a sustained biocontrol efficiency, when compared to the use of N. tenuis alone. In addition, plant feeding activities of mirids were significantly reduced when predators were used jointly (vs. N. tenuis alone). The applicability of zoophytophagous predators as biocontrol agents could be facilitated by simultaneously releasing two (or more) heteropteran predator species instead of a single one. [ABSTRACT FROM AUTHOR]

[Display omitted] • EPN symbiotic bacteria and their filtrates have insecticidal effects on T. absoluta. • The bacterium X. nematophila was the most effective against larvae of T. absoluta. • 1st/2nd instar larvae of T. absoluta were more susceptible than 3rd/4th instar. • The EPN, their bacteria and filtrates were also tested on the key predator N. tenuis. • The EPN symbiotic bacteria and their filtrates had low impact on N. tenuis. The use of biocontrol agents, such as predators and entomopathogenic nematodes, is a promising approach for the effective control of the tomato leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidaean), an oligophagous insect feeding mainly on Solanaceae species and a major pest of field- and greenhouse-grown tomatoes globally. In this context, the effects of two entomopathogenic nematode species Steinernema carpocapsae (Weiser) (Rhabditida: Steinernematidae) and Heterorhabditis bacteriophora (Poinar) (Rhabditida: Heterorhabditidae), as well as their respective bacterial symbionts, Xenorhabdus nematophila and Photorhabdus luminescens (Enterobacterales: Morganelaceae), which were applied as bacterial cell suspensions and as crude cell-free liquid filtrates on T. absoluta larvae, were investigated. The results showed that of all treatments, the nematodes S. carpocapsae and H. bacteriophora were the most effective, causing up to 98 % mortality of T. absoluta larvae. Regarding bacteria and their filtrates, the bacterium X. nematophila was the most effective (69 % mortality in young larvae), while P. luminescens and both bacterial filtrates showed similar potency (ca. 48–55 % mortality in young larvae). To achieve a holistic approach of controlling this important pest, the impact of these factors on the beneficial predator Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) was also studied. The results demonstrated that although nematodes and especially S. carpocapsae , caused significant mortality on N. tenuis (87 %), the bacterial cell suspensions of X. nematophila and P. luminescens and crude cell-free liquid filtrates had minimum impact on this beneficial predator (∼11–30 % mortality). [ABSTRACT FROM AUTHOR]

Tomato leafminer Tuta absoluta (Meyrick) is one of the most important pests that cause yield and quality loss in tomato cultivation in greenhouse and open field. T. absoluta, has spread rapidly in tomato production areas after emerging to Turkey in 2009. The pest is widely found along growing season in greenhouses and open fields in the coastal part of Antalya, where suitable climatic conditions are present. However, the population status of T. absoluta in tomato cultivation in greenhouses under high altitude highland conditions is not known and the study has been handled for this purpose. this study were conducted in 2018-2019 in Elmali and Korkuteli districts of Antalya province. In the study the population density of immature stage of T. absoluta were determined by leaf sampling and adult population density were determined by using pheromone traps for two years at four different locations. In addition, the natural enemies of the pest were also determined. As a result of the study, the pest was found widespread throughout the season in tomato greenhouses under highland conditions. Bracon concolorans Marshall, 1900, (Hymenoptera:Braconidae) Bracon variegator Spinola, 1808 (Hymenoptera:Braconidae) and Nesidiocoris tenuis (Reuter, 1895) (Hemiptera: Miridae) have been identified as natural enemies. As for parasitoid of T. absoluta, B. variegator was determined as the first time in Turkey with present study. [ABSTRACT FROM AUTHOR]

Abstract Background The misuse of chemical insecticides has developed the phenomenon of habituation in the whitefly Bemisia tabaci (Gennadius) causing enormous economic losses under geothermal greenhouses in southern Tunisia. Results In order to develop means of biological control appropriate to the conditions of southern Tunisia, the efficacy of the native strain of the predator Nesidiocoris tenuis Reuter (Hemiptera: Miridae) and two entomopathogenic fungi (EPF) Beauveria bassiana and Lecanicillium muscarium was tested against Bemisia tabaci (Gennadius). Indeed, the introduction of N. tenuis in doses of 1, 2, 3, or 4 nymphs per tobacco plant infested by the whitefly led to highly significant reduction in the population of B. tabaci, than the control devoid of predator. The efficacy of N. tenuis was very high against nymphs and adults of B. tabaci at all doses per plant with a rate of 98%. Likewise, B. bassiana and L. muscarium, compared to an untreated control, showed a very significant efficacy against larvae and adults of B. tabaci. In addition, the number of live nymphs of N. tenuis treated directly or introduced on nymphs of B. tabaci treated with the EPF remained relatively high, exceeding 24.8 nymphs per cage compared to the control (28.6). Conclusions It can be concluded that the native strain of N. tenuis and the EPF tested separately were effective against B. tabaci. Their combined use appears to be possible.

The abandonment of insecticide treatments to achieve sustainable crop production calls for a combination of methods to obtain satisfactory pest control. To this end, net houses and biological control are two promising methods, though we suspected that most natural enemies are blocked outside the net houses. In Kenya, tomato crops are particularly threatened by Trialeurodes vaporariorum (Westwood 1856) and Tuta absoluta (Meyrick, 1917) that are targets of most insecticide treatments in this country. We investigated in an on-farm experiment (i) the abundances of T. vaporariorum and T. absoluta in open fields and in net houses, (ii) the diversity of arthropod natural enemies of these pests, and (iii) the effect of net houses on the natural regulation. To complete, in the laboratory, we checked the capacity of natural enemies to pass through different net types. We identified several natural enemies, mainly the mirid bug Nesidiocoris tenuis (Reuter 1895) that was the most abundant predator for both pests. One parasitoid species was also identified for each pest, i.e. Encarsia formosa Gahan (1924) and Copidosoma sp. for T. vaporariorum and T. absoluta respectively. Net houses reduced drastically the pest populations. Predators were less abundant under net houses, while parasitoids did not seem to be affected by the nets. Encarsia formosa was shown to be able to pass through the different net types, while N. tenuis adults were not. These results raise the potential for augmentative biological control under net houses. Using kairomones to attract natural enemies, or introducing natural enemies under the net houses through inoculative releases, are two approaches to increase the abundance of natural enemies under net houses. [ABSTRACT FROM AUTHOR]

In order to know the local predators of Tuta absoluta Meyrick (1917) in Côte d'Ivoire and their host plants, a survey was carried out in 15 vegetable growing areas in 15 cities across the country. The study took place from November 2019 to February 2020. It concerned mainly tomato crops and African eggplant crops but also some companion plants such as tobacco. Observations were made on 30 plants per plant species. Farmers were questioned about the phytosanitary practices they use to protect their crops against pests. In total, 208 predators were captured. The predators collected were Heteroptera from the Miridae family: Nesidiocoris tenuis Reuter (1895) (51.92%); Nesidiocoris volucer Kirkaldy (1902) (30.28%) and Macrolophus pygmaeus Rambur (1839) (17.78%). These predators were collected on tobacco (45.19%), tomato (32.21%) and African eggplant (22.60%), except for the species N. volucer which was collected only on tobacco. The survey revealed that for pest management, 69% of the producers used conventional products and 31% used biological control method based on plant extracts. Insect predators were mainly collected on non-treated plants such as tobacco or on crops with a biological protection (78.85%). The plant extracts used by farmers, preserved insect predators much better than conventional treatments. Actually, these generalist predators complement the effect of plant extracts as they can feed on a large number of pests from different species such as T. absoluta or Bemisia tabaci and at different stages (eggs, larvae). Host plants such as tobacco could be used by farmers to attract and maintain these insect predators in vegetable areas, or even to introduce them into crops under cover such as greenhouse or net house. [ABSTRACT FROM AUTHOR]

Recent studies have suggested that predatory mirid bugs may be an effective alternative for controlling aphids in sweet pepper greenhouses. This study examined the effect of three constant temperatures (18, 24, and 30 °C) on the life history traits of predatory mirid species Nesidiocoris tenuis, Macrolophus pygmaeus, and Dicyphus bolivari, preying on the aphid Myzus persicae nicotianae in sweet pepper plants. As the temperature increased, the survival rate decreased for M. pygmaeus and D. bolivari, while for N. tenuis, it was the opposite, and their survival increased. When considering all the biological traits studied together, the estimated intrinsic rate of increase (rm) decreased as the temperature increased for M. pygmaeus and D. bolivari. In contrast, the rate increased as the temperature increased for N. tenuis. These results suggest that M. pygmaeus and D. bolivari are better adapted to lower temperatures than N. tenuis, which is more adapted to warm temperatures. The implications of these results for improving the biological control of aphids in sweet pepper greenhouses through the use of mirid bugs are discussed in relation to different temperature regimes.

Plant essential oils (PEOs) are being studied as a potential alternative to synthetic pesticides in agriculture. PEOs have the potential to control pests both directly, by being toxic or repellent to pests, and indirectly, by activating plant’s defense mechanisms. In this study, the effectiveness of five PEOs (Achillea millefolium, Allium sativum, Rosmarinus officinallis, Tagetes minuta, and Thymus zygis) on controlling Tuta absoluta and their impact on the predator Nesidiocoris tenuis was examined. The study revelead that PEOs from A. millefolium and A. sativum-sprayed plants significantly reduced the number of T. absoluta-infested leaflets and did not affect the establishment and reproduction of N. tenuis. Additionally, the spraying of A. millefolium and A. sativum increased the expression of defense genes in the plants, triggering the release of herbivory-induced plant volatiles (HIPVs), such as C6 green leaf volatiles, monoterpenes, and aldehydes, which can be messengers in tritrophic interactions. The results suggest that PEOs from A. millefolium and A. sativum can provide a dual benefit for controlling arthropod pests, as they can directly exhibit toxicity against these pests while also activating plant defense mechanisms. Overall, this study provides new insights into using PEOs as a sustainable solution for controlling pests and diseases in agriculture, by reducing synthetic pesticides and promoting the use of natural predators.

Mirid bug, Nesidiocoris tenuis is a voracious predatory bug that is spontaneously present in horticultural crops. Recently, it has been reported and practiced as a biocontrol agent against several insect pests. In the present study, we have evaluated mirid bug's predatory potential against Tuta absoluta developmental stages. Eggs, 1st, 2nd and 3rd larval instars of T. absoluta were seemingly the most preferred by all feeding stages of the mirid bugs. The 4th larval instar and pupae of T. absoluta were not pre-selected to feed during any stage of N. tenuis. As the T. absoluta immature stages grew in size, their total prey consumption decreased. The olfactory bioassay was performed for the adults of N. tenuis against tomato plants infested with various developmental stages of T. absoluta, using a Y-tube olfactometer. The results revealed that the early stages of T. absoluta, especially eggs emit volatiles to allure the N. tenuis adults. These outcomes enriched the resources for mass rearing of N. tenuis and their efficacy in the field, which will undoubtedly aid the farmers in the prevention of crop damage due to pests and control the tomato pinworm. [ABSTRACT FROM AUTHOR]

As non-chemical methods are not always effective to manage pests, the search for chemical solutions that efficiently combat pest species, while safeguarding the environment and beneficial organisms, is essential for advancing effective Integrated Pest Management (IPM) programs. Here, we investigated the efficacy of commercially available pesticides in managing Nesidiocoris tenuis , an emerging threat in the cultivation of tomato in Northwest Europe, while preserving the biocontrol agent Macrolophus pygmaeus. Fourteen pesticides were assessed for their residual toxicity on adults and nymphs in laboratory experiments, after which the most promising candidate was evaluated in cages and semi-commercial greenhouse conditions. Among the pesticides tested, chlorantraniliprole, hexythiazox, tebufenozide and azadirachtin had minimal impact on both insect species, with less than 37.5% corrected mortality. Pirimicarb, sulfoxaflor, acetamiprid, flupyradifurone, thiacloprid, tebufenpyrad, spinosad, indoxacarb, and a mixture of pyrethrins and piperonyl butoxide were harmful to N. tenuis , but also affected M. pygmaeus (up to 100% mortality). Emamectin benzoate was moderately effective to N. tenuis adults (87%) and nymphs (80%), but had limited effects on M. pygmaeus. Application of emamectin benzoate at the maximum recommended concentration resulted in a significantly higher mortality of N. tenuis adults (85%) compared to M. pygmaeus (53%) in cage experiments, while it significantly reduced N. tenuis nymphs and the number of necrotic rings in a greenhouse experiment. Emamectin benzoate emerges as a promising candidate for inclusion in IPM programs. However, further research is necessary to determine its compatibility with other management strategies for controlling N. tenuis and other tomato pests. Laboratory, cage and greenhouse trials indicate the potential of emamectin benzoate to be included in IPM programs to control Nesidiocoris tenuis , with less adverse effects on the beneficial Macrolophus pygmaeus. [Display omitted] • Nesidiocoris tenuis is an emerging pest in the cultivation of tomato in NW Europe. • 14 pesticides tested for their toxicity on N. tenuis and Macrolophus pygmaeus. • Emamectin benzoate most promising, killing N. tenuis and less affecting M. pygmaeus. • Higher mortality of N. tenuis compared to M. pygmaeus in cage experiments. • Dose-dependent reduced N. tenuis population and less necrotic rings in greenhouse. [ABSTRACT FROM AUTHOR]

The silverleaf whitefly (Bemisia tabaci) and the South America tomato pinworm (Tuta absoluta) are two of the most destructive pests of tomato. Open-field tomato production frequently relies on chemical treatments, which has been shown to lead to pesticide resistance. The integration of biological control using predatory mirid bugs is an effective alternative method for managing these pests. However, methods to establish and maintain populations of zoophytophagous mirids are not adequately described. We explored the potential use of two mirids naturally occurring in Florida, Nesidiocoris tenuis and Macrolophus praeclarus. We conducted 6 field experiments over 4 consecutive years to develop a strategy to maintain the mirids. Pre-plant inoculation of tomato plants did not lead to their establishment, likely due to the low prevalence of prey. We explored the use of sesame (Sesamum indicum) to retain the mirids. Intercropping sesame maintained the populations of N. tenuis throughout the duration of the crop. Macrolophus praeclarus never established in any of the open-field experiments. Nesidiocoris tenuis damage was minimal (B. tabaci, an established pest, and provide options to tomato growers should T. absoluta invade USA.

Generalist and specialist predators are successfully used in biocontrol programs in greenhouse vegetable crops, like tomato. A greenhouse ecosystem is rather simple and provides an excellent opportunity for developing predator–prey decision models. Three systems were selected: (1) the generalist predatory bug Macrolophus pygmaeus and the greenhouse whitefly Trialeurodes vaporariorum, (2) the generalist predatory bug Nesidiocoris tenuis and the tobacco whitefly Bemisia tabaci and (3) the specialist predatory mite Phytoseiulus persimilis and the spider mite Tetranychus urticae. The study is based on an extensive field dataset. No complex mathematical predator–prey models were developed. A binomial variable was given the value of "0" for the period when the pest was not under control. As soon as the population declined after the peak density, this variable was given a value of "1". The relationship between the densities of the prey and the predator was checked using a logistic regression model. The validated models do not calculate future pest densities but rather predict when pest control should be initiated, based on the number of pests and predators present at a certain time. Numerical simulation of the prey isoclines showed an L-shaped curve for the generalist predators and a linear curve for the specialist predators. Our simple, empirical modelling approach provides satisfactory models for biocontrol purposes. When combined with a standardized monitoring protocol, these models can be implemented in decision tools. In the future, more data will allow a machine learning approach, in which additional parameters like temperature, humidity, and time can be included. [ABSTRACT FROM AUTHOR]

Nesidiocoris tenuis is a zoophytophagous mirid bug widely studied for its role in preying on major greenhouse pests. Since N. tenuis has now been known for its vigorous predation potential on pests such as Bemisia tabaci, many applied entomologists are now recommending that N. tenuis be merged into the Integrated Pest management (IPM) systems. However, successful integration of N. tenuis into any IPM system depends on thorough evaluation with compatible pesticides, as incompatible pesticides can offset the whole idea of IPM. Here, we simulate the field situation where N. tenuis feeds directly on a contaminated B. tabaci nymph or leaves. However, instead of using live B. tabaci nymphs, we used brine shrimp eggs, Artemia salina (Linnaeus, 1758). Brine shrimp eggs have been reported to be an excellent factitious supplementary diet in augmenting N. tenuis populations. Thus, we use brine shrimp eggs to determine the toxicity of pesticides, to which the calculated mortality rates can be used to determine which pesticides can be used together with N. tenuis in an IPM system against any related pest. • We developed a customized containment system that promotes aeration and minimize contamination. • Pesticide contaminated hatched brine shrimp eggs is delivered to N. tenuis in the aerated containment system. • In addition to established methods such as leaf dipping or insect dipping, this method shows to mimic N. tenuis feeding on contaminated B. tabaci nymphs in field conditions thus, predicts how a pesticide may be of toxic or compatible with N. tenuis when both are integrated together.

Bemisia tabaci Gennedius (1889) est un ravageur phytophage affectant diverses cultures partout dans le monde. La lutte biologique contre B. tabaci se base sur l’utilisation de ses ennemis naturels surtout les parasitoïdes et les prédateurs. Dans ce contexte, plusieurs espèces parasitoïdes du genre Eretmocerus et Encarcia et des prédateurs (comme Nesidiocoris tenuis) dont l’efficacité a été prouvée, sont utilisées dans la lutte contre cette mouche blanche. L’évaluation des potentialités du parasitoïde indigène Encarsia sophia a montré une performance à limiter les populations de B. tabaci dans les serres géothermiques dans le Sud Tunisien. Cependant à 25°C et à une humidité relative variable entre 55 et 75%, le taux de parasitisme d’E. sophia des larves L2, L3 et L4 de B. tabaci sur culture d’aubergine est de 14,72 ± 5,60%. Il est conclu que l’usage cet ennemi indigène de B. tabaci peut remédier la multiplication de ce ravageur.

Zoophytophagous mirid species, that feed and develop either on prey or plant resources, are often found simultaneously on the same host. Hence, these species can engage in both intraguild predation and cannibalism, which can pose a threat to mirid eggs. Ovipositing females may respond to such risks of predation on their eggs by reducing the number of eggs laid or selecting safer oviposition sites. We tested the oviposition behavior of Macrolophus pygmaeus (Rambur) (Hemiptera: Miridae) females under the risk of cannibalism by M. pygmaeus males and intraguild predation by Nesidiocoris tenuis (Reuter) males (Hemiptera: Miridae) under laboratory conditions. Intraguild predators and cannibals were introduced during or after the oviposition period. The number of eggs laid (using counts of newly hatched nymphs) and their proportion on each part of a tomato plant were both measured. The results reveal that only cannibalism by M. pygmaeus males after the period of oviposition significantly decreased the number of hatched eggs. Cannibalism thus represents a greater risk to mirid eggs than intraguild predation. The M. pygmaeus female responded to the presence of potential intraguild predators (or competitors) by decreasing the number of eggs laid in the upper leaves. The results suggest that M. pygmaeus females avoid competition by N. tenuis, by laying fewer eggs on upper leaves. Cannibalism could regulate zoophytophagous predator populations under prey scarcity conditions and minimize the risk of crop damage associated with those biological control agents. [ABSTRACT FROM AUTHOR]

Zoophytophagous plant bugs feed on plant tissue as a source of water and nutrients, besides feeding on prey. By phytophagy, mirid predators activate plant defense responses through different pathways, resulting, among others, in the release of herbivore‐induced plant volatiles (HIPVs). These compounds could repel herbivores and attract parasitoids and predators, and synthetic versions could potentially be used in biological control. Nevertheless, little is known about the influence of synthetic volatiles on mirid attraction. Using Y‐tube olfactometer trials, we evaluated the responses of Nesidiocoris tenuis (Reuter), Macrolophus pygmaeus (Rambur), and Dicyphus bolivari Lindberg (Hemiptera: Miridae), important natural enemies used to control various greenhouse pests, to 10 synthetic versions of HIPVs released from tomato (Solanum lycopersicum L., Solanaceae) plants induced by N. tenuis and M. pygmaeus. Nesidiocoris tenuis responded to five of the 10 HIPVs, whereas M. pygmaeus and D. bolivari responded to four of the 10 HIPVs. Two green leaf volatiles, (Z)‐3‐hexenyl propanoate and (Z)‐3‐hexenyl acetate, and the ester methyl salicylate (MeSA) were attractive to all three mirid predator species. Our results demonstrate that the volatiles released by tomato plants activated by N. tenuis and M. pygmaeus phytophagy are attractive to their conspecifics and also to D. bolivari. Further studies should evaluate the potential of these compounds to attract predatory mirids in the field. [ABSTRACT FROM AUTHOR]

Dicyphine mirids are one of the most important groups of predators on tomato. In the Mediterranean region, several species in the genera Dicyphus, Macrolophus, and Nesidiocoris (Hemiptera: Miridae, Bryocorinae, Dicyphini) colonize protected horticultural crops. In Portugal, Nesidiocoris tenuis (Reuter) is increasingly abundant in the mirid species complex of tomato crops and appears to be displacing the native Dicyphus cerastii Wagner. In order to know whether intraguild predation (IGP) can explain the decreasing abundance of D. cerastii, we evaluated predatory interactions between adult females and first instars of D. cerastii vs. N. tenuis but also D. cerastii vs. Macrolophus pygmaeus (Rambur), as this species is also naturally present in horticultural crops in Portugal. Cannibalistic interactions were also tested for the same three species. All experiments were performed under laboratory conditions, in Petri dish arenas, in the presence or absence of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs as alternative prey. Predation on both heterospecific and conspecific nymphs occurred only in the absence of alternative food. Intraguild predation was mutual and symmetrical between D. cerastii and M. pygmaeus. However, IGP was asymmetrical between D. cerastii and N. tenuis, favouring the first. Cannibalism was not significantly different among these mirid species. Our results show that D. cerastii has a greater capacity to feed on intraguild prey than N. tenuis. Therefore, IGP on small nymphs does not explain the abundance shift between D. cerastii and N. tenuis. [ABSTRACT FROM AUTHOR]

Successful integrated pest management in protected crops implies an evaluation of the compatibility of pesticides and natural enemies (NE), as control strategies that only rely on one tactic can fail when pest populations exceed NE activity or pests become resistant to pesticides. Nowadays in Almería (Spain), growers release NE prior to transplanting or early in the crop cycle to favor their settlement before pest arrival because this improves biocontrol efficacy, although it extends pesticide exposure periods. The purpose of this research was to evaluate the compatibility of two applications of pesticides with key NE in 2‐year trials inside tomato and sweet pepper commercial greenhouses: Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae), Orius laevigatus (Say) (Hemiptera: Anthocoridae) and Amblyseius swirskii (Athias‐Henriot) (Acari: Phytoseiidae). In tomato, flubendiamide and chlorantraniliprole (IOBC category 1) were compatible with N. tenuis, but chlorpyrifos‐methyl and spinosad (IOBC categories 2–3), which effectively reduced Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) density, compromised its predatory activity. In sweet pepper, chlorantraniliprole (IOBC category 1) was the only pesticide compatible with O. laevigatus while chlorantraniliprole, emamectin benzoate, spirotetramat and pymetrozine were harmless (IOBC category 1) to Amblyseius swirskii, and sulfoxaflor slightly harmful (IOBC category 2) to this phytoseiid predator. [ABSTRACT FROM AUTHOR]

To develop an augmentative biological control programme for Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) and Thrips palmi Karny (Thysanoptera: Thripidae) using Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae), we studied the life history traits of a Japanese strain of N. tenuis reared on B. tabaci and T. palmi in controlled environments. The lower developmental threshold during the nymphal period was far higher than those estimated for Spanish, Moroccan, and Iranian strains, indicating that the Japanese strain is better adapted to higher temperatures than the other three strains tested. The intrinsic rate of increase rm was highest at 30 °C and lowest at 20 °C. The rm value for individuals reared on T. palmi at 25 °C was lower than that for individuals reared on B. tabaci at the same temperature. Implications of these results for the biological control of B. tabaci and T. palmi in greenhouses are discussed. [ABSTRACT FROM AUTHOR]

Nesidiocoris tenuis is a zoophytophagous insect widely used commercially as a biological control agent against different pests and crops under greenhouse conditions. For a successful Integrated Pest Management (IPM) strategy, it is crucial to know the compatibility of available and new crop protection products with biological control agents. The aim of this study was to evaluate and classify the lethal and sublethal effects of different crop protection products on the biological control agent N. tenuis , including the novel insecticides dimpropyridaz and Beauveria bassiana strain PPRI 5339, in accordance with the International Organisation for Biological and Integrated Control (IOBC) directives. Dimpropyridaz, B. bassiana PPRI 5339, the adjuvant fatty acid esters and the combination of B. bassiana PPRI 5339 with the adjuvant have been classified as harmless (IOBC 1 < 25% of mortality and beneficial capacity). The evaluation of reproduction and capacity for increase (r c) showed no significant sublethal effects between the previous compounds and the untreated control. Flupyradifurone, sulfoxaflor, and dimethoate were classified as harmful (IOBC 4 > 75% of mortality and beneficial capacity). The compatibility of these two new products (dimpropyridaz and B. bassiana PPRI 5339) with Nesidiocoris tenuis is of great importance because it adds new tools to be used in IPM programmes in which chemical and biological control strategies are used together. • Dimpropyridaz and Beauveria bassiana were not harmful to nymphs of Nesidiocoris tenuis. • Both products showed no deleterous effects on female fertility. • They also were not harmful to life span of adult females. • The capacity of increase of N. tenuis was not affected the two products. [ABSTRACT FROM AUTHOR]

Despite their importance as biological control agents, zoophytophagous dicyphine mirids can produce economically important damage. We evaluated the phytophagy and potential impact on tomato plants of Dicyphus cerastii and Nesidiocoris tenuis. We developed a study in three parts: (i) a semi-field trial to characterize the type of plant damage produced by these species on caged tomato plants; (ii) a laboratory experiment to assess the effect of fruit ripeness, mirid age, and prey availability on feeding injuries on fruit; and (iii) a laboratory assay to compare the position of both species on either fruit or plants, over time. Both species produced plant damage, however, although both species produced scar punctures on leaves and necrotic patches on petioles, only N. tenuis produced necrotic rings. Both species caused flower abortion at a similar level. Overall, N. tenuis females produced more damage to tomato fruit than D. cerastii. There was an increased frequency of D. cerastii females found on the plants over time, which did not happen with N. tenuis. Our results suggested that, although D. cerastii caused less damage to fruit than N. tenuis, it still fed on them and could cause floral abortion, which requires field evaluation and caution in its use in biological control strategies.

The effect of temperature on the functional response of female adults of Nesidiocoris tenuis Reuter to different densities of Bemisia tabaci (Gennadius) pupae was assessed. Three constant temperatures (15, 25, and 35°C) and six prey densities (5, 10, 20, 35, 50, and 70) were tested over a 24-h period. Nesidiocoris tenuis exhibited a type II functional response at 15 and 25°C, and a type III response at 35°C. The number of prey consumed by the predator increased with increase in the prey density at all temperatures. Temperature influenced attack rates and handling times. The highest attack rate occurred at 35°C at high densities (35, 50, and 70 prey) and the lowest handling time was recorded at 35°C. The maximum attack rates (T/Th) were 17.13, 42.12, and 45.07 whitefly pupae per day at 15, 25 and 35°C, respectively. As a result, the value of a/Th indicates that N. tenuis was relatively more efficient in attacking B. tabaci at 35°C than at lower temperatures. Results suggest that the ability of N. tenuis to detect and consume B. tabaci over a broad range of temperatures, especially high temperatures (25-35°C), makes this mirid a good candidate for the biological control of whiteflies in warm environments, such as greenhouses.

Heated greenhouse cultivation in southern Tunisia constitutes a very important axis of agricultural development. Among the problems that are prejudicial to glasshouse tomato crops heated by geothermal waters, the newly introduced Tuta absoluta insect remains little studied in this agro-ecosystem. Biological means in the context of an integrated fight against this formidable pest to better understand the geothermal sector and contribute to the study of this new problem. The monitoring of a population of a native strain of Nesidiocoris tenuis installed naturally in the geothermal greenhouse and a population of one strain introduced into another greenhouse, showed the performance of the indigenous strain which multiplied rapidly and remained until the end of cultivation with a large population arriving at the total elimination of Tuta absoluta.