To be or not to be fragrant: floral scent of some bat-pollinated cacti.

Floral scent is a key olfactory cue in both diurnal and nocturnal pollination systems. In the case of nocturnal systems, such as bat-pollinated flowers, odour seems to play a more important role than visual cues. Cactaceae include many bat-pollinated species; however, few studies have investigated the olfactory cues in this family. We analysed and compared the chemical composition of the floral bouquet of three chiropterophilous cactus species, among which are a pair of congeners that differ considerably in scent intensity. Our research presents novel findings regarding the floral scent chemistry of chiropterophilous cactus species. We documented the first case of a bat-pollinated cactus whose flowers lack perceptible floral scent and in which no volatile compounds were detected in our chemical analyses. Additionally, we provide a comprehensive analysis of the chemical composition of the floral bouquet of the other two bat-pollinated species, revealing a resemblance among closely related species within the same genus. We highlight the need for further studies using biotests to investigate the mechanisms through which bats find flowers lacking scent.

Mapping ethnobotanical aspects of the iconic Mandacaru cactus, Cereus jamacaru DC. in Brazil: a scientometric review.

Cereus jamacaru DC. occurs in the central-eastern region of Brazil and is among the best-known cacti in the country. Its phytochemical properties and fruits hold great significance to the local communities. We examined published ethnobotanical studies regarding C. jamacaru (mandacaru) undertaken between 2000 to 2024, to better understand its traditional uses and relationships with human communities in Brazil. The literature review was carried out by consulting the databases Google Scholar (166 articles), Scopus (1 article) and Web of Science (2 articles), and followed the PRISMA 2020 protocol. A total of 169 articles were identified, of which 45 were deemed relevant. The most frequent uses of C. jamacaru include medicinal (cited in 32 articles), human consumption as a non-conventional food (22), and forage (18). C. jamacaru is often cited to treat health conditions such as kidney problems, flu and inflammations, but it's also used for construction and crafts. Our results highlight the diverse and vital uses of C. jamacaru for human communities. Furthermore, we demonstrate the pattern of knowledge production regarding the ethnobotany of this species and the challenges for its conservation and the preservation of associated traditional knowledge.