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The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), has invaded most Afro-Eurasian countries and is threatening worldwide tomato production. Various strategies have been developed and implemented to manage this pest. Here, we present a timely review on the up-to-date development and practical implementation of integrated pest management (IPM) programs for tomato crops across different world regions infested by T. absoluta. While insecticide resistance is a growing concern, biological control via releasing or conserving arthropod natural enemies and sex pheromone-based biotechnical control are the most successful management practices. Agronomic control-related research is an emerging area where the soil fertilization and/or irrigation, as well as breeding of resistant cultivars, has the potential to enhance IPM effectiveness. Grower survey responses in the native areas (i.e., South America), early-invaded areas (i.e., first report between 2006 and 2012) and newly invaded areas (i.e., first report after 2012) showed that the control programs evolved along with the areas and time since invasion. Growers in the early-invaded areas shifted more rapidly from chemical control to biological control compared to those from the native area. In all concerned regions, the pest control failure risk following chemical insecticide applications and the high cost associated with either biological or biotechnical control methods have been the greatest concerns for growers. The information gathered from the native and/or early-invaded areas may help achieve a more effective management in newly invaded areas. Lastly, researchers are expected to break the bottlenecks of some key issues that would enable lowering application cost of novel biorational alternative management options.

Over the last decade, the tomato russet mite, Aculops lycopersici, has become a major pest in tomato crops worldwide, both in open-field and protected cultivation. Its minute size of 150 to 200 μm complicates early detection and monitoring in tomato crops. Passive dispersal occurs via air currents, crop management practices and commercial trade. Chemical control of Aculops lycopersici is difficult. Altered product use from broad spectrum pesticides towards selective acaricides, to meet integrated pest management (IPM) standards, has created better conditions for the rapid expansion of this specialized eriophyid mite. Moreover, practical implementation of promising natural enemies is challenging due to the complexity of biological control in tomato crops. Trichomes on tomato negatively affect arthropod natural enemies, but provide a refuge for the tomato russet mite. Despite the cosmopolitan nature of Aculops lycopersici, knowledge associated with IPM is limited and fragmented. This review describes fundamental biological data on Aculops lycopersici from the last 20 years and novel developments in the field of prevention, monitoring, chemical and biological control. The recent analysis of the genome sequence will be helpful in the development of a sustainable control strategy for Aculops lycopersici. © 2021 Society of Chemical Industry.

The tomato russet mite (TRM), Aculops lycopersici, is a worldwide pest of cultivated tomatoes. Currently, no effective biological control agents are available on the market. Therefore, chemical spray applications are required. Fast and reliable detection, monitoring and evaluation of interventions are a challenge, slowing down the development of an appropriate integrated pest management (IPM) strategy. This study describes a binomial sampling plan with the aim to reduce the efforts and costs for an accurate monitoring of A. lycopersici. Sampling was performed by taking pictures of the upper leaf surface with a smartphone through an attached magnification lens. A binomial sampling plan was developed based on the linear relationship between ln(mean TRM densities) and ln(-ln(1-P-T), where P-T is the proportion of samples with more than T (tally threshold) mites. The minimum precision threshold of 0.30 was determined for the different models. A resampling for validation of sample plans (RVSP) programme with a fixed sample number was used for validation of the model on an independent data set. The binomial sampling plans were validated at tally thresholds of T = 9 and T = 15 with fixed sample sizes of 15, 20, 25 and 30. Precision levels were satisfying within a range of P-T-values from 0.29 to 0.97 for T = 15 at a fixed sample size of 20. This range was much smaller for T = 9, where the P-T-values range between 0.40 and 0.92 at the same sample size. A binomial sampling model with T = 9 with a fixed sample size of 15, which has the lowest time investment, is feasible for glasshouse tomato growers in practice. However, for the development of pest management programmes, a more intensive and more accurate binomial sampling plan with T = 15 and a sample size of minimum 20 is suggested.

Background The zoophytophagous predator Macrolophus pygmaeus Rambur (Hemiptera: Miridae) is a successful biocontrol agent against several pest species in protected tomato crops. This predator is considered to be harmless for the crop. However, in recent years, Heteroptera feeding punctures on tomato fruit in Belgian and Dutch greenhouses have been misinterpreted as Pepino mosaic virus (PepMV) symptoms. In this study, three hypotheses were tested: (1) M. pygmaeus causes fruit damage that increases with population density and surpasses economic thresholds; (2) the presence of prey or alternative prey reduces the damage; (3) an infection of the tomato plants by PepMV triggers or aggravates M. pygmaeus fruit damage. Results At increasing M. pygmaeus densities, the severity of fruit damage increased from a few dimples towards yellowish discoloration and deformed fruits. A correlation with an infection with PepMV was found. The severity of the symptoms was independent of the presence of prey. A minimum economic density threshold was estimated at 0.32 M. pygmaeus per leaf. Conclusion M. pygmaeus can cause economic damage to tomato fruits at densities common in practice. An infection of the plants with PepMV enhances fruit symptoms significantly. Interacting plant defence responses are most likely the key to explaining this, although confirmation is required. © 2015 Society of Chemical Industry.

Macrolophus pygmaeus Rambur (Hemiptera: Miridae) is a key biological control agent in greenhouse tomato crops. In the present study, we describe the population dynamics of M. pygmaeus after release during two generations in semi-commercial greenhouses in order to optimize biocontrol programs. We tested the effect of the number of weekly supplementary food applications consisting of a mixture of Ephestia kuehniella Zeller and Artemia franciscana Kellogg in a tomato crop on population numbers of M. pygmaeus at low and high initial release densities of the predator. Also, the effect of supplementary feeding on the predator's dispersal was studied. Larger population densities of M. pygmaeus were obtained when food was supplied for a longer period. However, we observed fruit damage by M. pygmaeus at high densities resulting from too frequent food applications. Also, dispersal was slowed down as the number of supplementary food applications increased. Distributing M. pygmaeus over more plants at release results in higher total population densities. The optimal inoculative release strategy of M. pygmaeus is a trade-off between high population densities and fruit damage, fast or slow dispersal throughout the greenhouse and the number of release plants and work/costs related to the supplementation of food. The optimal strategy to overcome negative effects like fruit damage, slow dispersal and potential cannibalism proved to be a weekly provision of supplementary food during 6-8 weeks, with an initial release density strategy of 20 M. pygmaeus adults per plant. These results contribute to a more sustainable tomato production. A reliable and efficient inoculative release strategy for the key predator M. pygmaeus enhances the biocontrol potential and is of great value for tomato growers.

Raw vegetables can become contaminated with bacteria that cause foodborne illness, degrade food quality or reduce product shelf life. Since fresh produce can become contaminated at any point from cultivation to consumption along the food supply chain, it is essential to apply a whole-chain approach tomanaging food safety and quality. The Institute forMicrobial Control of the Food Chain (iMIK) was established in Belgium to examine the different processes and stakeholders in the entire food supply chain, to identify critical points concerning food safety and quality, and to provide the food industry with an evidence-based approach to food safety management that is supported by scientific data. In this chapter, case studies of food safety controls at the different stages of the supply chain are presented, such as the impact of harvest procedures on fresh produce microbiology and the evaluation of fresh produce in the cold chain. Based on the results obtained, critical points were identified and processes were modified to improve food safety and quality. The data presented in this chapter clearly demonstrate the usefulness of a whole-chain approach to effective food safety management and quality assurance of fresh produce.

The zoophytophagous predator Macrolophus pygmaeus Rambur (Hemiptera: Miridae) is a successful biocontrol agent against several pest species in protected tomato crops. This predator is considered to be harmless for the crop. However, in recent years, Heteroptera feeding punctures on tomato fruit in Belgian and Dutch greenhouses have been misinterpreted as Pepino mosaic virus (PepMV) symptoms. In this study, three hypotheses were tested: (1) M. pygmaeus causes fruit damage that increases with population density and surpasses economic thresholds; (2) the presence of prey or alternative prey reduces the damage; (3) an infection of the tomato plants by PepMV triggers or aggravates M. pygmaeus fruit damage.At increasing M. pygmaeus densities, the severity of fruit damage increased from a few dimples towards yellowish discoloration and deformed fruits. A correlation with an infection with PepMV was found. The severity of the symptoms was independent of the presence of prey. A minimum economic density threshold was estimated at 0.32 M. pygmaeus per leaf.M. pygmaeus can cause economic damage to tomato fruits at densities common in practice. An infection of the plants with PepMV enhances fruit symptoms significantly. Interacting plant defence responses are most likely the key to explaining this, although confirmation is required. © 2015 Society of Chemical Industry.

Two iolinid predatory mites were studied in the laboratory as potential biological control agents of the tomato russet mite, Aculops lycopersici (Acari: Eriophyidae). The development, reproduction and predation capacity of Pronematus ubiquitus and Homeopronematus anconai (Acari: Iolinidae) on A. lycopersici were investigated. Developmental time from egg to adult at 25°C averaged 9.59, 9.31 and 9.52 days for P. ubiquitus on A. lycopersici, A. lycopersici and Typha angustifolia pollen, and pollen only, respectively. H. anconai required 11.18, 10.39 and 11.90 days to complete development on the respective diets. Survival of the immature stages exceeded 83% on all diets for both iolinids. In experimental arenas, both predators caused a substantial reduction of the immature population development of A. lycopersici. The number of tomato russet mite offspring was reduced by 78% and 57% by P. ubiquitus and H. anconai, respectively. The addition of pollen to the arena lowered this population reduction to 35% and 27% for the respective predators. However, supplementing a diet of tomato russet mites with pollen significantly increased the fecundity of both predatory mites from 14–15 to 24–25 eggs over a five-day period. The results suggest that both P. ubiquitus and H. anconai have good potential to suppress A. lycopersici populations and that T. angustifolia pollen can support population establishment of the predators.