Cowpea, Vigna sp., is an important, low-cost protein source in subtropical and semi-arid regions, where seasonal rainfall makes storage necessary. However, the weevils Callosobruchus maculatus and C. chinensis cause significant grain losses during storage. While synthetic fumigants are commonly used to control these pests, their risks to mammals have prompted the search for safer alternatives. In this context, we tested palo santo, Bursera graveolens, essential oil with limonene, α-phellandrene, o-cymene and β-phellandrene, menthofuran, and germacrene-D as a sustainable approach. This plant is readily accessible, produces high fruit yields, and is used in households for various purposes. We evaluated the fumigant toxicity, repellency, and ovicidal effects of B. graveolens essential oil on both Callosobruchus species. Our results showed that B. graveolens oil was toxic to C. maculatus (LC₅₀ = 80.90 [76.91–85.10] µL) and C. chinensis (LC₅₀ = 63.9 [60.95–66.99] µL), with C. chinensis being more susceptible (SR = 1.27). Molecular docking analyses revealed that all the oil’s compounds bind to both the GABA and octopamine receptors, exhibiting high energy affinities; however, germacrene shows the strongest affinity in these receptors. C. chinensis was strongly repelled at all concentrations, while C. maculatus was repelled only at lethal concentrations. No ovicidal effect was observed in either species. In conclusion, our findings suggest that B. graveolens essential oil is a promising and sustainable protectant for stored cowpeas in small-scale storage units.

Growth factors selectively activate calcium signaling pathways in the cell nucleus, which in turn regulate gene transcription and other intranuclear events, but the specific way this is accomplished is not entirely understood. Growth factors increase inositol 1,4,5-trisphosphate (IP3) in the nucleus, which in turn releases calcium from intranuclear IP3 receptors (ITPRs), and the present study shows that this leads to transient assembly of an actin nucleoskeleton that associates with intranuclear non-muscle myosin 2A (MYH9). Mass spectrometry suggests that much of the MYH9 cargo consists of components of the gene transcription machinery, and chromatin immunoprecipitation identified a number of specific genes that associate with the myosin in response to stimulation with growth factors. Together, these findings suggest that growth factors initiate gene transcription by transiently assembling an actin nucleoskeleton that works with MYH9 to bring specific genes to the transcription machinery.

The induction of resistance in plants involves prior activation of physiological and biochemical systems in the face of external stimuli, promoting greater tolerance to biotic stresses. Faced with the growing challenge of emerging diseases in agricultural plants and the search for more sustainable phytosanitary practices, natural substances are promising alternatives. Xylopia frutescens, known as “pindaiba-da-folha-pequena”, native to the Brazilian Cerrado and traditionally used as an antimicrobial treatment, is still little-explored in the literature and presents potentially effective compounds for the control of plant diseases. This study characterized the chemical composition and thermal stability of the X. frutescens essential oil (XEO), while evaluating its physiological and phytotoxic effects and the potential for disease control in maize and cowpea plants. The main constituents found in X. frutescens essential oil were nopinone (13.75%), spatulenol (12.94%), myrtenal (12.47%), and β-pinene (11.02%). Thermogravimetric analysis indicated that X. frutescens is highly volatile, with a large mass loss at 94.74 °C. In bioassays, the oil preserved chlorophyll levels at adequate amounts and activated several antioxidant mechanisms, but also showed a dose-dependent phytotoxic effect. In vitro assays further confirmed its antifungal activity against key phytopathogens, supporting its potential use in disease control. A general increase in the activities of the enzymes superoxide dismutase (SOD), ascorbate peroxidase (APx) and—partially—chitinase (CHIT) was observed. Catalase (CAT) decreased in both maize and cowpea plants treated with this essential oil but was higher in untreated infected plants. Such enzymatic changes suggest that the oil acts as a natural elicitor of resistance, strengthening biochemical and physiological defenses. Finally, disease severities, as measured by AUDPCs, demonstrated significant reductions in the progress of maize “Curvularia leaf spot” (Curvularia lunata) and cowpea “Web blight” (Rhizoctonia solani). The results highlight the potential of X. frutescens essential oil as an active compound stimulating defense mechanisms for applications in sustainable agricultural systems.

Os microrganismos endófitos são promissores no campo agrícola como potenciais estimuladores de crescimento. Assim, foi avaliado o potencial estimulador de fungos endofíticos na soja (Glycine max (L.) Merril. Inicialmente foram coletadas 12 amostras de fungos endofíticos em diversas partes de várias espécies de plantas cultivadas. Estes fungos foram isolados, identificados e cultivados e em processo de fermentação durante 72h. Após deste processo foi preparada uma concentração ao 60% para ser aplicada. Plântulas de soja previamente semeadas em potes de plástico de 500 ml contendo substrato esterilizado e sem nenhum tipo de adubação e com 7 dias de idade foram pulverizadas com 5mL da solução previamente preparada. As plântulas foram mantidas em estufa a 28°C e fotoperíodo 12 horas. Após de 8 dias desde a aplicação dos extratos foram avaliados o tamanho e o diâmetro do caule e a raiz. Posteriormente a massa fresca e seca usando uma balança de precisão foi avaliada. Os resultados evidenciaram que dos 12 fungos aplicados nas plântulas, oito incrementaram significativamente o comprimento do caule, com um maior destaque para as plantas tratadas com Purpureocillium lilacinum e Penicillium citrinum. Já o diâmetro do caule foi maior em todos os tratamentos exceto nas plantas tratadas com Penicillium citrinum. O comprimento da raiz também foi incrementado significativamente quando tratados com algumas espécies de fungos. Similarmente a massa aérea e radicular também foi incrementada dependendo dos tratamentos. Conclusivamente nossos resultados mostram o potencial uso destes fungos como bioestimuladores radiculares o de caule da soja.

Ruta chalepensis (Rutaceae), commonly known as rue, is traditionally recognized for its medicinal applications and cultural associations with mysticism. In addition to its ethnobotanical relevance, R. chalepensis has been reported to possess insect-repellent and pesticidal properties. However, domestication and the adoption of monoculture practices can compromise inherent plant defenses, potentially increasing susceptibility to herbivore pressure. In this context, we report, for the first time, the occurrence of infestations by the highly polyphagous aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) on R. chalepensis cultivated under Neotropical conditions. The infestations were documented in commercial rue fields located in the Zona da Mata region, Minas Gerais, Brazil, in two consecutive years. Plant material was taxonomically verified and deposited in the VIC Herbarium at the Universidade Federal de Viçosa. Aphid specimens, including both apterous and alate morphs, were examined under a stereomicroscope to confirm species identity. Field sampling revealed a notable interaction between M. persicae and native natural enemies, particularly predatory spiders. Aphid density per plant declined markedly from 14.1 to 6.2 individuals, coinciding with an observed increase in spider activity. These findings expand our understanding of M. persicae’s ecological plasticity and highlight the vulnerability of non-conventional crops to generalist pests. They also underscore the importance of implementing targeted pest surveillance and integrated pest management (IPM) approaches in underutilized or alternative cropping systems.