Introdução: Alelopatia é uma forma de adaptação química dos vegetais, e quando liberado no meio ambiente pode influenciar diretamente ou indiretamente o crescimento e o desenvolvimento de plantas que estão ao seu redor. Objetivo: Avaliar in vitro o potencial alelopático, do extrato aquoso de folhas secas de Mimosa pudica L. sobre a germinação e o crescimento inicial da alface (Lactuca sativa). Metodologia: O extrato de M. pudica, obtido por maceração estática, foi diluído em água destilada, e utilizado cinco concentrações (2, 4, 6, 8 e 10g.L-1). Para o bioensaio de germinação, foram utilizadas placas de Petri, forradas com papel filtro, umedecido com 4 mL dos extratose 25 sementes de alface por repetição. As sementes foram mantidas em incubadora, tipo B.O.D., a 24 ºC e fotoperíodo de 12 horas. Os parâmetros avaliados foram IVG, %G, massa seca, comprimento da radícula e hipocótilo (mm), e os teores de clorofila a, b e total. Resultados: Na análise do IVG, %G, comprimento radicular, teor de clorofila a, b e total demostraram uma redução da germinação e no crescimento da alface a partir do aumento das concentrações do extrato. No crescimento do hipocótilo nas menores doses, apresentaram o efeito hormese e, no teste da massa seca, não demostrou diferença significativa entre as concentrações. Conclusão: Os extratos aquosos de M. pudica possuem efeito alelopático sobre o desenvolvimento inicial da alface. Palavras-chave:Sensitiva; Bioensaios; Aleloquímicos.

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Understanding the responses of seeds to the detriment of the interaction of external factors is one of the challenges of research, especially with little explored species such as Sonchus oleraceus L. Thus, the objective was to investigate the effect of the cultivation system, storage time and temperature on the physiological potential of seeds of Sonchus oleraceus L. Seeds were used of two cultivation systems (organic and conventional) in three storage times (0, 90 and 180 days) and submitted at two temperatures (20 and 30 ºC). For the evaluation of germination, the first count, germination percentage and germination speed index were determined, while root length and hypocotyl growth were determined for the evaluation of seedling growth. The first count was statistically higher than 180 days in both crops and temperatures. The seeds of conventional cultivation obtained higher germination percentage and germination speed index at 30 ºC. There was a reduction in root and hypocotyl growth at 180 days, especially at 20 °C. The cultivation environment influences the seed quality of Sonchus oleraceus L. during storage.

Minimally processed vegetable products are defined as ready-toeat or ready-to-use foods in culinary preparations that have undergone one or a few basic procedures, such as washing, sanitization, elimination of nonedible portions such as peels and seeds, and cutting (Graca et al., 2020;Monteiro et al., 2016;Padrón-Mederos et al., 2020). Although minimal processing has become a method to add value and encourage the consumption of vegetable foods, maintaining the sensory and nutritional quality and the freshness of these products is a technological challenge for the industry (Rodriguez-Arzuaga et al., 2020;Simões et al., 2020). Minimally processed fruits and vegetables (MPFVs) deteriorate more easily than intact fruits and vegetables because the mechanical damage caused by cutting and peeling compromises the integrity of their cells and imposes stress on their tissues. Damage to cells culminates in an increased rate of biochemical and physiological changes and makes plant tissues more susceptible to microbial growth, which together may result in changes in color, flavor, aroma, and texture (Denoya