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The use of endophytic entomopathogenic fungi (EEF) represents a promising strategy to boost plant resistance in crops against both biotic and environmental stresses. However, the mechanisms by which this inoculation influences constitutive and herbivore-induced defenses to protect plants against pest insects remain unclear. To address this gap, we investigated whether the inoculation of the EEF Metarhizium robertsii can modulate sugarcane plant defenses and their resistance against the sugarcane borer Diatraea saccharalis. Specifically, we examined the endogenous levels of jasmonic acid (JA) and salicylic acid (SA), as well as the volatile emissions in sugarcane, in the absence and presence of infestation caused by D. saccharalis. We also explored how these inoculations might affect the oviposition preference of D. saccharalis (direct defense) and the chemotaxis of its main natural enemy, the parasitoid Cotesia flavipes (indirect defense), commonly used in biological control programs. Our findings revealed that M. robertsii inoculation alters sugarcane plant chemical traits, affecting their resistance differently against D. saccharalis infestation. In non-infested plants, the inoculation of M. robertsii increased JA and SA phytohormones, suppressed volatile emissions, and reduced egg-laying by D. saccharalis , while exhibiting no effect on C. flavipes attraction. Conversely, in D. saccharalis- infested plants, M. robertsii increased JA content and reduced SA levels, resulting in quantitatively different volatile emissions. These changes increased attraction of C. flavipes compared to infested plants without fungal inoculation. Our results demonstrate that M. robertsii inoculations can enhance sugarcane plants' constitutive defenses against D. saccharalis while improving their herbivore-induced indirect defenses in sugarcane. • M. robertsii alters sugarcane chemistry depending on D. saccharalis infestation. • In non-infested plants, M. robertsii increased SA and JA levels, suppressed volatile emissions and D. saccharalis oviposition. • Plants with M. robertsii and D. saccharalis infestation increased JA and volatiles, attracting C. flavipes. • M. robertsii can bolster constitutive and induced defenses against D. saccharalis in sugarcane. [ABSTRACT FROM AUTHOR]

Structural supramolecular architectures in the solid state of 1,5-diketone malonates 1a-g are proposed to construct a small library of hydrogen bonds by C–H⋯O interactions by crystal structure analysis. A possible route of crystallization mechanism at different levels of hierarchy considers the next strategic steps: a) Intramolecular interactions provide a kite-like molecular conformation. b) Intermolecular interactions provide molecular recognition between the structural unit, synthon, and macrocycles. c) The supramolecular architectures obtained from the conjunction of the multiple functions performed by the C–H⋯O interactions. X-ray studies and Hirshfeld Surface Analysis are described. [ABSTRACT FROM AUTHOR]

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The article discusses the military and political history of San Luis Potosí, Mexico in the late 19th century. The author focuses on the political uprising of the soldiers led by General Francisco de Aguirre, the role of former President of Mexico Benito Juárez, and General Mariano Escobedo. Other topics mentioned include the history of elections in Mexico, opposition to electing a governor, and governor Juan Bustamante. Social hierarchies in Mexico as well as the democratization of Mexico are explored.

While phytoplasma infections in plants are known to affect their interactions with aboveground herbivores, the impact of different genotypes on these infections and their effects on belowground herbivores remains largely unexplored. In cranberry (Vaccinium macrocarpon), infection by the phytoplasma Candidatus Phytoplasma sp. subgroup 16SrIII-Y leads to false blossom disease. This study investigates whether cranberry infection by this phytoplasma affects the performance and feeding behavior of a foliar feeder (spongy moth, Lymantria dispar) and a root feeder (oriental beetle, Anomala orientalis). Using phytoplasma-infected and uninfected cranberries of two genotypes ("Ben Lear" and "Crimson Queen"), the survival, growth and consumption of L. dispar and A. orientalis larvae were measured. To assess the effects on plant morphological and chemical traits, we also examined the impact of phytoplasma infection on shoot and root growth, carbon and nitrogen content, and the levels of defensive compounds such as proanthocyanidins (PACs). Results indicate that larvae of L. dispar and A. orientalis generally showed larger size and more efficient tissue consumption on infected plants, with these effects varying by cranberry genotype, possibly due to differences in phytoplasma titer. Phytoplasma infection was associated with stunted growth, elevated nitrogen content, and lower PAC levels in both shoots and roots of infected cranberry plants compared to uninfected ones. These findings indicate that phytoplasma infection potentially manipulates plant chemical composition by increasing nutrient levels and decreasing defensive compounds, enhancing herbivore performance both above and belowground. This study sheds light on the intricate interplay among plants, phytoplasma infection, and insect herbivore communities., (© 2024 Institute of Zoology, Chinese Academy of Sciences.)

Lower elevations are generally thought to contain a greater abundance and diversity of insect communities and their natural enemies than higher elevations. It is less clear, however, how changes in seasons influence this pattern. We conducted a 2-year study (2013‒2014) in guava orchards located in a tropical Andean forest of Peru to investigate differences in fruit flies (Diptera: Tephritidae) and their parasitoid communities at two elevations and over two seasons. Fruit fly traps were installed, monitored, and guava fruits were sampled from eight orchards at low (800-950 m above sea level) and high (1,700-1,900 m above sea level) elevations and during the dry and rainy seasons. At each orchard, adult fruit fly trap captures and emergence of fruit flies and their parasitoids from guava fruit were quantified to determine their abundance and species composition. There was a greater abundance and species richness of fruit flies captured in traps at lower elevations, as well as higher abundance and species evenness of fruit flies that emerged from fruit, indicating that lower elevations are associated with larger fruit fly populations. The abundance, species richness and diversity of parasitoids were also greater at lower elevations. Consequently, guava fruit infestation and fruit fly parasitism rates were also greater at lower elevations. Seasonality also influenced fruit fly populations with a greater number of flies emerging from guava fruit and more fruit infested in the rainy season. However, seasonality had no effect on parasitoid population parameters or rate of parasitism, nor did it interact with elevation as an influence of populations of fruit flies or their parasitoids in guava orchards. This study highlights the importance of examining both elevation and seasonality for a better understanding of the population dynamics of fruit flies and their parasitoids in tropical agroecosystems., Competing Interests: The authors have declared that no competing interests exist.