Nasturtium (Tropaeolum majus) is an ornamental and medicinal plant that has edible flowers. Drought and salt stress decrease flower production and quality, including affecting sugar metabolism and ethylene production. Ethylene can accelerate the nasturtium senescence process, decreasing its postharvest quality. The use of polyamines, mainly spermine, may be a strategy for reducing the harmful effects of these stresses on the metabolism of sugars and phenolic compounds and for decreasing the production of ethylene, which accelerates senescence, in nasturtium flowers. Therefore, the objective here was to evaluate the role of spermine application on sugar and phenolic compounds and on ethylene production in nasturtium flowers grown under drought and salt stress. Two experiments were performed in isolation and at the same time in order to achieve this. Spermine down-regulated ethylene production and up-regulated the content of sugars and phenolic compounds on nasturtium flowers grown under drought and saline stress. Sugars and phenolic compounds down-regulated ethylene production in nasturtium flowers. Spermine can be used to mitigate the harmful effects of drought and salt stress on nasturtium flowers by increasing sugar and phenolic compounds and decreasing ethylene production.

Drosophila suzukii (Matsumura) is a relevant pest affecting berries and stone fruits globally, including in the Neotropical region, where its invasion was reported about a decade ago. Despite chemical control being the main management method for D. suzukii, data on insecticide susceptibility in Neotropical D. suzukii populations are scarce. Here, we assessed the susceptibility of three field-collected Brazilian D. suzukii populations to four insecticides (i.e., deltamethrin, permethrin, spinetoram, imidacloprid) and contrasted this with a standard insecticide-susceptible population. Using the discriminating concentration (LC₉₀) from the standard susceptible population, we identified resistant populations. Synergist exposure (piperonyl butoxide, triphenyl phosphate, diethyl maleate) indicated the role of detoxification enzymes in resistance. Our results showed that deltamethrin was the most toxic, followed by spinetoram, permethrin, and imidacloprid. While all field populations were similarly susceptible to pyrethroids and spinosyns, one population from Minas Gerais (i.e., Paula Candido) had significantly lower imidacloprid susceptibility, with only 53.4 ± 5.2% mortality at 10.0 g/L (the equivalent of 10-fold the estimated imidacloprid LC₉₀). Only piperonyl butoxide increased the imidacloprid susceptibility of Paula Candido flies. Our findings indicate the occurrence of cytochrome P450 enzyme-based imidacloprid resistance in the state of Minas Gerais, which can challenge the management of D. suzukii in Brazil.

The spotted-wing drosophila, Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae), is an invasive pest of thin-skinned and stone fruits with growing economic impact worldwide. In Brazil, it was first reported in 2013 and has since spread across major fruit-producing states. Although previously detected in Rio de Janeiro (RJ), records were limited to isolated individuals, never in commercial orchards. Here, we provide the first evidence of D. suzukii establishment in a commercial ‘Biloxi’ blueberry, Vaccinium corymbosum Linnaeus, field in Sapucaia, RJ. Initial vinegar traps captured seven females, confirmed in the laboratory. Subsequent banana–yeast bait traps collected both sexes, including one male, confirming establishment. Emergence assays from naturally damaged fruits demonstrated reproductive success, resulting in approximately 279 individuals (110 males and 169 females) from a total of 1.6 kg of damaged fruits. Monitoring also detected Zaprionus spp. (Diptera: Drosophilidae), another invasive drosophilid associated with fruit damage. To assess management options, we evaluated susceptibility of this D. suzukii population to imidacloprid. Bioassays showed that exposure to 0.140 mg/mL (LC50 for a susceptible reference strain) killed approximately 50% of adults, indicating local susceptibility, in contrast to reduced susceptibility reported in other Brazilian strains. Collectively, these findings confirm D. suzukii establishment in a new blueberry-producing region, reveal potential phytosanitary risks, and suggest that chemical control options remain effective locally. This integrated evidence highlights the importance of early monitoring and management strategies to safeguard Brazil’s expanding blueberry industry.