Parasitoids play a key role in biological control, regulating pest populations in natural and agricultural ecosystems. Their efficiency depends on a thorough understanding of host–parasitoid interactions. Among these, the functional response, the relationship between parasitism rate and host density, plays a critical role. Despite a well-established background, challenges remain in experimental design, model selection, and parameter estimation for functional response analysis in parasitoids. This study aims to provide a practical guide to addressing these challenges. We outline key considerations in experimental design, including the selection of model organisms and initial host densities. For model selection, we present methods to differentiate between Type II and Type III functional responses, identifying the best-fitting models for parasitoids. In parameter estimation, we present an example demonstrating the application of functional response models for each type, including parameter estimation to guide model choice. Additionally, we provide equations and code based on published data to facilitate parameter comparisons. This guide provides a structured framework for experimental design, parameter estimation, and model selection in functional response studies, which is adaptable to various host–parasitoid interactions. By enhancing methodological rigour, we aim to support researchers in improving the precision and applicability of functional response analyses in parasitoid research.

This study investigates the gut microbiota of newly emerged adult females and males of five economically important Anastrepha species (Tephritidae) – A. ludens, A. obliqua, A. serpentina, A. striata, and A. fraterculus – by analyzing 16S rRNA amplicon sequences from 36 samples collected from ecologically relevant fruit hosts and locations in Mexico. We chose to concentrate only on newly emerged adults to identify bacteria that females could potentially transmit vertically to progeny via oviposition, a topic that remains poorly studied. Results revealed that Proteobacteria dominated the microbiota in all species, but substantial variation was observed in genus-level composition. Differentially abundant genera included Enterobacter, Gluconobacter, Tatumella, Providencia, Ochrobactrum, Siccibacter, Sphingobacterium, and Sphingobium. Significant differences in alpha diversity were observed between species, particularly between A. obliqua and A. striata, and between A. obliqua and A. serpentina based on the Shannon index. Anastrepha ludens, A. obliqua, and A. striata males exhibited higher species richness than females, although these differences were not statistically significant within individual species likely due to limited sample size. Interestingly, across all species, significant differences in microbiota composition were observed between males and females. Our findings suggest that morphological, physiological (i.e., metamorphosis) and ecological factors, such as possible gut structural differences and host fruit preferences, may influence the composition of the gut microbiota, potentially affecting the ecological adaptability and pest behavior of these flies.

The fungus Beauveria bassiana (Unioeste 76) was tested against the soybean pest Euschistus heros in laboratory, greenhouse, and field. In the laboratory, insects were sprayed with pure conidia (TC) suspended in distilled water or in an oil dispersion formulation (OD; vegetable oil) at a concentration of 109 conidia/mL. The UV-B radiation and heat tolerance of the conidia were also assessed. After 12 days, the mortality rates in the laboratory were 70% for the TC treatment and 80% for the OD treatment. In the greenhouse pre-infestation bioassay, which used soybean plants in cages, the fungal treatments resulted in 52% and 47% mortality for the TC and OD formulations, respectively. In the post-infestation bioassay, both fungal treatments caused 83% mortality. In the field trial conducted on soybean plots (14 × 18 m), the treatments included: (i) biological: OD (109 conidia/mL); (ii) chemical insecticide; (iii) biological + chemical, all applied at 150 L/ha. Insect numbers were evaluated using beating-sheet sampling. In the final population sample, the biological treatment showed a population density similar to the chemical treatment (0.94 and 0.83 insects/m, respectively), both below the economic threshold. Conidia tolerance to UV-B radiation was similar across both treatments, but conidia in oil were less tolerant to heat. These results suggest that strategically combining both approaches (B. bassiana with chemical insecticides), with careful consideration of application intervals, could provide a sustainable and effective method for managing natural populations of E. heros.

Sitotroga cerealella (Olivier) (Lepidoptera: Gelechiidae) is one of the most serious pests of rice. The variations in phytoconstituents of rice cultivars (Miniket, Cottondora Sannalu, Gobindobhog, Swarna, and Tulaipanji) that led to differences in population growth of S. cerealella were studied. Fitness of the moth was approximated in terms of mean generation time (Tc), net reproductive rate (NRR or R0), intrinsic rate of population increase (rm), etc. Considering potential fecundity (Pf), growth rates, mortality coefficient (MC), and expected population size in the second generation (PF2), we classified the susceptibility of the rice cultivars to S. cerealella in the order as M > C > G > S > T. This was despite the higher concentrations of all the tested primary metabolites (PMs) in C and T. The least susceptibility of T and lower susceptibility of C than M can be attributed to their higher levels of secondary metabolites (SMs). M was highly susceptible due to its lowest SM content and sufficient levels of PMs. Now, G and S contained lower amounts of SMs, but they were moderately susceptible owing to the lower PM content. This emphasises the role of SMs, such as phenols, flavonoids, tannins, saponins, alkaloids, phytates, and oxalates, in determining the susceptibility of crop cultivars. Although none of the rice cultivars were entirely resistant, it can be stated that Miniket requires more protection measures against S. cerealella during storage than the others.

The study systematically investigated the key biological and ecological characteristics of Cyamophila willeti, a major pest of the tree species Styphnolobium japonicum. We focused on its circadian mating rhythm, oviposition preference, and the effects of temperature on population parameters. Using the age-stage, two-sex life table approach, we compared the development, reproduction, and population growth potential under different temperature conditions. Results showed that mating activity peaked at 12:00 and 17:00, with females significantly preferring shoot tips for oviposition. At 25°C, female and male adult longevities were 39.88 ± 0.93 and 46.71 ± 1.69 days, respectively, and the mean fecundity per female was 647.75 ± 52.94 eggs. At 29°C, longevity was significantly reduced to 11.88 ± 4.10 days for females and 13.89 ± 4.31 days for males, while fecundity decreased to 47.63 ± 4.26 eggs. Most nymphs did not develop beyond the fifth instar at 33°C. These findings indicate that the optimal temperature for population growth of C. willeti is around 25°C, whereas high temperatures (≥29°C) significantly suppress survival and reproduction. This study establishes a foundation for monitoring C. willeti and developing effective control strategies.

The objective of this experiment was to evaluate the resistance of advanced tomato genotypes resulting from an interspecific cross between Solanum lycopersicum and Solanum pennellii to Tetranychus urticae and Phthorimaea absoluta. The plant materials included nine lines, 14 hybrids, Leblon F1 (commercial control), and the wild accession S. pennellii LA716 as a resistance standard. Acylsugar content was then determined. For mite bioassays, oviposition, adult mortality/survival, egg hatching, and nymphs were evaluated using a no-choice bioassay. For P. absoluta bioassays, the oviposition, intensity of damage, type of lesions, and percentage of damaged leaflets were evaluated. F1 (TOM-808 × BPX-443E-03-02-113-02), F1(TOM-810 × BPX-443E-03-02-113-02), F1(TOM-808 × TOM-717), F1(TOM-808 × TOM-757), and F1(TOM-810 × TOM-717) were the most resistant to the mite, exhibiting higher female mortality, reduced oviposition, and no nymph emergence observed. The genotypes F1(TOM-808 × TOM-667), F1(TOM-808 × TOM-717), F1(TOM-810 × TOM-615), and several lines, which exhibited reduced oviposition and foliar damage. The results of the bioassays indicated that high acylsugar content reduced oviposition and foliar damage of the tested pests. The hybrid F1(TOM-808 × TOM-717) is the most promising at this stage of the breeding program, as it shows resistance to both tested pests.

Predatory mites are important biological control agents of spider mites in various crops. Long-term mass rearing on alternative foods, such as plant pollen, may affect their predatory efficiency, but data on Euseius scutalis are scarce. Therefore, this study aimed to evaluate whether long-term rearing of E. scutalis on cattail pollen influences its functional response when fed on Tetranychus turkestani. Functional and numerical responses of the predatory mite E. scutalis reared on cattail (Typha latifolia) pollen over 30 generations on different densities (2, 4, 8, 16, 32, 64, and 128) of T. turkestani were evaluated. The results indicated a type II functional response for E. scutalis on T. turkestani in all generations (G1, G10, G20, and G30) tested. The attack rate (a) of E. scutalis increased as the number of generations increased. The handling time decreased as the number of generations increased from G1 (0.330 h) to G10 (0.318 h), then increased in G20 (0.572 h) and then decreased again in G30 (0.385 h). In G1 and G30, the number of eggs deposited by the predator increased as prey density increased. However, in G10 and G20, egg deposition increased up to 64 prey and then slightly decreased at 128 prey. The results indicated that the quality of E. scutalis did not lessen against T. turkestani after different periods of rearing on cattail pollen. Based on this study, we recommend cattail pollen as a good candidate for the large-scale rearing of E. scutalis for use in biological control programmes against T. turkestani.

Haritalodes derogata (Fabricius) (Lepidoptera: Crambidae), commonly known as the cotton leaf roller, is an important polyphagous pest that causes damage to various agricultural and forest plants, especially those of the Malvaceae family, but also to crops such as cotton, cashew, bamboo, oats, and jute. While microbial control agents are known for their efficacy and environmental friendliness, there are few studies demonstrating their effect on H. derogata. The aim of this study was to evaluate the bioefficacy of microbial agents from different pathogen groups against this pest. To this end, we investigated the insecticidal potential of fifteen indigenous microbial isolates from our entomopathogen collection. These included five Bacillus thuringiensis strains (Bn1, MnD, Mm2, Xd3, Lyd8), five entomopathogenic fungi (Metarhizium flavoviride As2, M. anisopliae KTU-51 and Beauveria bassiana Pa4, Pa5, Hp5), and five baculoviruses (HycuGV-Hc1, LdMNPV-T2, AcMNPV, DapuNPV-T1, SeMNPV-U), applied at concentrations of 1.8 × 109 cfu/mL, 1 × 107 conidia/mL, and 1 × 107 PIB/mL, respectively, against H. derogata larvae under laboratory conditions. Among these, B. thuringiensis subsp. kurstaki Bn1, B. bassiana Pa4, Hyphantria cunea granulovirus (HycuGV-Hc1), and Spodoptera exigua nucleopolyhedrovirus (SeMNPV-U) showed strong insecticidal activity and were selected for virulence assays, each achieving 100% mortality in third instar larvae. The median lethal concentrations (LC50) were determined to be 7.1 × 104 cfu/mL, 3.3 × 103 conidia/mL, 1.2 × 103 PIB/mL, and 1 × 103 PIB/mL, respectively. These results indicate that indigenous microbial agents are a promising environmentally friendly alternative to chemical pesticides in the control of H. derogata.

The European red spider mite, Panonychus ulmi Koch (Acari: Tetranychidae), is a major mite pest affecting a wide range of crops globally. Its rapid development and extensive dispersal enable P. ulmi to form large colonies through arrhenotokous reproduction, which subsequently produces bisexual offspring following oedipal phase mating. In this study, life tables for arrhenotokous and bisexual P. ulmi populations were constructed and assessed using the age-stage two-sex life table theory. To assess whether maternal age affects the offspring sex ratio, 3D life table analysis was conducted for both groups. Population projection for P. ulmi bisexual and arrhenotokous was based on life table data to evaluate the effect of arrhenotokous reproduction on population growth. Bisexual population parameters were r = 0.1828 d−1, λ = 1.2006 d−1, R0 = 44.80 offspring, and T = 20.79 d. The theoretical calculation of these parameters cannot be performed solely based on the survival rate and female fecundity of the P. ulmi arrhenotokous population, as only male offspring were produced during the first seven days before the arrival of the bisexual population. Although arrhenotokous parthenogenesis yields fewer offspring than bisexual reproduction, it significantly influences population dynamics by enabling a single virgin female to establish a bisexual population. Controlling offspring sex ratios enables rapid population growth and colonisation of new habitats. A comprehensive understanding of arrhenotokous reproduction is crucial for developing effective management strategies for P. ulmi. Future research should integrate genomic, ecological, and evolutionary perspectives to bridge the gap between laboratory and field conditions.

The distribution and abundance of insect pests are influenced by landscape structure and composition, particularly through modifications to biocontrol services and the proportion of suitable habitats within the landscape. In addition, pest populations are affected by agricultural practices at different landscape scales, ranging from field-by-field to area-wide. Our study focuses on one of the world’s most invasive and polyphagous pests of fruits and vegetables: the Oriental fruit fly, Bactrocera dorsalis (Hendel, 1912) (Diptera: Tephritidae). We analysed how farmer practices, landscape composition, and mango varieties were related to B. dorsalis infestation in an insular tropical agroecosystem with disparate farming systems, where crop plots are of modest size and interconnected with various habitat types. Fruit infestations were regularly recorded during 18 months in different plots on all mango varieties of the study area. Agricultural practices were determined through semi-structured interviews and categorised according to the farm structure and practices related to B. dorsalis management. Landscape composition was determined from high-resolution satellite imagery and local surveys, and the area of landscape cover was calculated within a 500 m buffer around each sampled orchard plot. We demonstrate that both landscape and local factors influence the infestation indexes of B. dorsalis in mango orchards. At a landscape scale, B. dorsalis was favoured by habitat diversity, which probably provided complementary larval food resources and enabled populations to maintain throughout the year. On a local scale, individual farmers’ practices had a significant influence on infestation indexes. The proportion of infested fruits was lower in plots managed by farmers who practised sanitation.

In tritrophic interactions, host plants could influence not only the population of insect pests but also that of their natural enemies. This study examined the effect of three wheat cultivars on demographic parameters of Schizaphis graminum Rondani (Hemiptera: Aphididae) and its predator, Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae). Furthermore, the secondary metabolites, photosynthetic pigments, and defence enzymes of wheat cultivars were evaluated at different times. According to the results, the highest and lowest developmental times of S. graminum were found on cultivar (cv.) Morvarid and cv. Ehsan, respectively. However, it was vice versa for the predator, being highest on cv. Ehsan and lowest on cv. Morvarid. Adults of S. graminum lived shorter on cv. Morvarid, while males and females of H. variegata lived longer on this cultivar. The intrinsic rate of natural increase (r) of S. graminum ranged from 0.347 to 0.456 day−1, and that of H. variegata from 0.118 to 0.176 day−1 on different cultivars. The value of this parameter was lowest for aphids but highest for their predator on cv. Morvarid. Based on the results, cv. Morvarid at 120 hours post-infestation by S. graminum contained the greatest concentrations of secondary metabolites and enzyme activities. The time-dependent loss of photosynthetic pigments occurred in each tested cultivar. The results revealed that cv. Morvarid had a suitable potential for reducing the population of S. graminum and enhancing the performance of H. variegata. However, further studies are needed to evaluate the complementary interactions of cv. Morvarid and H. variegata in controlling S. graminum population under natural conditions.

Soybean aphids (Aphis glycines) (Hemiptera: Aphididae) pose a serious threat to global soybean production, necessitating sustainable control strategies. This study investigated silica nanoparticles (SiNPs) as an eco-friendly alternative, hypothesising they would suppress aphid populations while enhancing plant growth. Soybean plants were foliar-sprayed with SiNPs (0–1 mmol/L), and aphids were assessed across six assays: fecundity, survival, feeding preference, weight gain, olfactory response, and plant morphometrics. SiNPs significantly reduced aphid nymphal production and population growth at all concentrations but did not affect survival, weight gain, or host-seeking behaviour. Plant responses were mixed: leaf width increased at higher SiNPs doses, but plant height decreased, with no effects on leaf length, root/shoot biomass, or root length. These findings suggest that SiNPs could disrupt aphid reproduction without triggering behavioural avoidance. The absence of biomass reduction indicates potential for crop compatibility. This laboratory study reveals a novel, reproduction-targeted mode of action for SiNPs, highlighting its potential as a candidate for future development in sustainable IPM strategies. Further field-scale validation is required to confirm these effects under real-world conditions.