The fall armyworm (Spodoptera frugiperda) is one of the most destructive pests of corn. New infestations have been reported in the East Hemisphere, reaching India, China, Malaysia, and Australia, causing severe destruction to corn and other crops. In Puerto Rico, practical resistance to different mode of action compounds has been reported in cornfields. In this study, we characterized the inheritance of resistance to chlorantraniliprole and flubendiamide and identified the possible cross-resistance to cyantraniliprole and cyclaniliprole. The Puerto Rican (PR) strain showed high levels of resistance to flubendiamide (RR₅₀ = 2,762-fold) and chlorantraniliprole (RR₅₀ = 96-fold). The inheritance of resistance showed an autosomal inheritance for chlorantraniliprole and an X-linked inheritance for flubendiamide. The trend of the dominance of resistance demonstrated an incompletely recessive trait for H1 (♂ SUS × ♀ PR) × and an incompletely dominant trait for H2 (♀ SUS × ♂ PR) × for flubendiamide and chlorantraniliprole. The PR strain showed no significant presence of detoxification enzymes (using synergists: PBO, DEF, DEM, and VER) to chlorantraniliprole; however, for flubendiamide the SR = 2.7 (DEM), SR = 3.2 (DEF) and SR = 7.6 (VER) indicated the role of esterases, glutathione S- transferases and ABC transporters in the metabolism of flubendiamide. The PR strain showed high and low cross-resistance to cyantraniliprole (74-fold) and cyclaniliprole (11-fold), respectively. Incomplete recessiveness might lead to the survival of heterozygous individuals when the decay of diamide residue occurs in plant tissues. These results highlight the importance of adopting diverse pest management strategies, including insecticide rotating to manage FAW populations in Puerto Rico and other continents.

This paper presents a multi-method approach for evaluating the utility and impact of agricultural databases in the context of the rapidly expanding digital economy. Focusing on the Arthropod Pesticide Resistance Database, one of the most comprehensive global resources on arthropod pesticide resistance, we offer a framework for assessing the effectiveness of agricultural databases. Our approach provides practical guidance for developers, users, evaluators, and funders on how to measure the impact of these digital tools, using relevant metrics and data to validate their contributions. Additionally, we introduce an index-based method that evaluates impact across multiple dimensions, including data usage, accessibility, inclusivity, knowledge generation, innovation, research and policy development, and collaboration. The detailed methodology serves as both a reference and a model for evaluating the impact of other agricultural databases, ensuring they effectively support decision-making and foster innovation in the agricultural sector.

Insects experience a diversity of subtoxic and/or toxic xenobiotics through exposure to pesticides and, in the case of herbivorous insects, through plant defensive compounds in their diets. Many insects are also concurrently exposed to antioxidants in their diets. The impact of dietary antioxidants on the toxicity of xenobiotics in insects is not well understood, in part due to the challenge of developing appropriate systems in which doses and exposure times (of both the antioxidants and the xenobiotics) can be controlled and outcomes can be easily measured. However, in Drosophila melanogaster, a well-established insect model system, both dietary factors and pesticide exposure can be easily controlled. Additionally, the mode of action and xenobiotic metabolism of dichlorodiphenyltrichloroethane (DDT), a highly persistent neurotoxic organochlorine insecticide that is detected widely in the environment, have been well studied in DDT-susceptible and -resistant strains. Using a glass-vial bioassay system with blue diet as the food source, seven compounds with known antioxidant effects (ascorbic acid, β-carotene, glutathione, α-lipoic acid, melatonin, minocycline, and serotonin) were orally tested for their impact on DDT toxicity across three strains of D. melanogaster: one highly susceptible to DDT (Canton-S), one mildly susceptible (91-C), and one highly resistant (91-R). Three of the antioxidants (serotonin, ascorbic acid, and β-carotene) significantly impacted the toxicity of DDT in one or more strains. Fly strain and gender, antioxidant type, and antioxidant dose all affected the relative toxicity of DDT. Our work demonstrates that dietary antioxidants can potentially alter the toxicity of a xenobiotic in an insect population.

This study examines resistance inheritance to the pyrethroid insecticides esfenvalerate and deltamethrin in a Puerto Rican strain of fall armyworm (FAW), Spodoptera frugiperda, a major global pest of corn. The resistant strain (PPR) showed significantly higher resistance compared to a susceptible strain (SUS), with a 62-fold X-linked and 15-fold autosomal-linked resistance ratio (RR₅₀) for esfenvalerate and deltamethrin, respectively. Resistance was incompletely dominant for both insecticides. Synergist bioassays revealed that detoxification enzymes play a key role in resistance, with PPR exhibiting increased toxicity across all tested synergists, especially with a 12-fold increase when all were combined. Deltamethrin assays confirmed the importance of these enzymes, with a 17-fold increase in PPR toxicity when combined with esterase inhibitors. These findings highlight the complexity of pyrethroid resistance, involving multiple non-target site mechanisms, and suggest that heterozygous individuals could survive in treated crops due to incomplete dominance. The results emphasize the need for diversified pest management strategies, including insecticide rotation, to effectively control FAW populations.

The growing global demand for blueberries (Vaccinium corymbosum L.), driven by their nutraceutical benefits, requires optimizing both yield and fruit quality—an increasingly complex goal under the influence of abiotic stress and intensifying climatic extremes. Non-linear nutrient accumulation curves and net daily absorption rates were developed for macro and microelements from biomass and tissue concentration data over 200 days after transplanting (DAT). Second-order polynomial models (R²ₐdⱼ ≥ 0.94) revealed dynamic uptake patterns, identifying critical windows of high demand and net physiological remobilization. The first phase (60-90 DAT) exhibited maximum uptake of phosphorus (P), calcium (Ca), magnesium (Mg), sulfur (S), and immobile micronutrients such as iron (Fe) (0.13 mg plant⁻¹ day⁻¹), zinc (Zn), and manganese (Mn), essential for vegetative expansion. In contrast, nitrogen (N) showed a distinctive decline in net absorption (–51.45 mg plant⁻¹ day⁻¹) between 90-120 DAT, indicating significant internal remobilization towards reproductive organs. The final stage (150-200 DAT) was dominated by intensive potassium (K) uptake (54.76 mg plant⁻¹ day⁻¹) for fruit filling, while Ca and micronutrient absorption (particularly boron [B] and copper [Cu]) plateaued or declined, reflecting limited xylem transport under the high temperatures (>39 °C) and vapor pressure deficits recorded at the site. These absorption dynamics were strongly influenced by root-zone thermal stress, which reached a peak of 39 °C during the late stages, affecting the nutrient use efficiency and final fruit quality. These results provide a quantitative foundation for designing fertilization strategies aligned with phenological development and aimed at enhancing nutrient use efficiency and fruit quality under tropical conditions.

The fall armyworm (FAW), Spodoptera frugiperda, threatens corn production worldwide due to severe defoliation and rapid evolution of insecticide resistance. This study evaluated resistance mechanisms in a Puerto Rico strain (PPR) resistant to the spinosyn insecticides spinosad and spinetoram, compared with a susceptible strain (SUS). Using diet-overlay bioassays, PPR showed high resistance, with RR₅₀ values of 214-fold for spinosad and 63.3-fold for spinetoram. Synergist assays with piperonyl butoxide (PBO), S,S,S-tributyl phosphorotrithioate (DEF), diethyl maleate (DEM), and verapamil hydrochloride (VER) increased susceptibility to the insecticides to varying degrees, providing indirect evidence that multiple detoxification and transport processes may contribute to resistance. For spinosad, the greatest synergistic effects were observed with DEM and DEF, whereas DEM and verapamil produced the strongest effects with spinetoram. These responses are consistent with the potential involvement of glutathione S-transferases, esterases, ATP-binding cassette transporters (ABC transporters) and cytochrome P450s; however, their specific roles require confirmation through biochemical and molecular analyses. Inheritance studies indicated that the degree of dominance was concentration-dependent and generally declined as insecticide concentrations increased. Resistance tended to be more dominant at lower concentrations, whereas the response became approximately additive at the highest concentrations tested, although the pattern varied between reciprocal crosses for spinetoram. These findings show that exposure to low or intermediate concentrations may favor the survival of heterozygotes and potentially contribute to the spread of resistance alleles. Overall, these findings support integrated resistance management through proper application rates and rotation insecticides with different modes of action, while identifying physiological processes that warrant further investigation.