Cassia is a diverse legume genus widespread in the (sub-)tropical zone of the world. Several studies have been done on this genus; however, significant changes have occurred at the taxonomic level over the years. this has led to inaccurate information about seed dormancy in Cassia since many species are no longer included in the genus. thus, our work aims to investigate and update the information about the kind of dormancy that occurs in seeds of Cassia species and also look into two notorious species in this group (C. fistula and C. javanica) to compare myxospermous vs. non-myxospermous seeds regarding dormancy and germination traits. Seed dormancy reports were found for 53 Cassia species, and the only kind of seed dormancy found for these species was physical dormancy (pY). nondormancy was not found, and all seeds had a blockage to water uptake during the dormant state, that is, all have PY. Of these 53 species, only 18 are currently included in the genus Cassia. C. fistula and C. javanica have fully developed embryos, and dormancy is only conferred by the (water-impermeable) seed coat. the lens in the seed coat is the only structure that creates a water pathway to break pY in C. fistula. Myxospermous seeds came out of dormancy faster than non-myxospermous ones. PY seems to be the only kind of seed dormancy that has evolved in Cassia. The extent of this kind of dormancy in all subtribe cassiinae is also discussed. Cassia L. sensu stricto was first proposed by Irwin and Barneby 1,2 , who segregated Cassia sensu lato into three genera (Cassia L., Chamaecrista Moech. and Senna Mill.), establishing the subtribe Cassiinae (Leguminosae: Caesalpinioideae). The genus Cassia was considered as the largest genus in Caesalpinioideae 3,4 , but currently it is comprised of only about 30 species 5. Their fruits usually are indehiscent (also divided by transversal septa), unlike those of Senna, which are typically dehiscent and without septa separating the seeds 2. The woody indehiscent pods of Cassia are quite tough, as well as the seeds. Additionally, Cassia fruits are not fleshy, but with remnants of pulp. The presence of these fruit traits suggests that large mammals could disperse Cassia seeds. However, a possible absence of seed dispersers for some species leads to speculation that these indehiscent fruits were likely dispersed by megafauna that are now extinct. Janzen and Martin 6 reported that some fruit traits are better related to extinct animals (seed dispersal anachronisms), since some tough fruits may not be consumed (and seeds dispersed) by smaller extant animals. The absence of dispersers affects seed fate 6 , not only because of the lack of dispersal but also due to the ability of dispersers to break over the tough fruits and release the seeds. Concerning seed dormancy, Baskin and Baskin 7 proposed a classification system that includes five classes (see Baskin and Baskin 7), wherein dormancy is associated with the embryo or other seed components (e.g. the seed coat). Among these five classes of dormancy, physic...
RESUMOEste trabalho trata-se de um relato de experiência sobre um projeto desenvolvido pelos integrantes do Programa de Educação Tutorial do curso de Ciências Biológicas (PET BIO PONTAL), juntamente com estudantes voluntários do mesmo curso da Universidade Federal de Uberlândia, Campus Pontal. O projeto envolveu os estudantes do 7º ano do ensino fundamental de uma escola pública estadual de educação especial do município de Ituiutaba-MG e teve como objetivo abordar conteúdos sobre a biodiversidade de organismos viventes no ambiente de hortaliças, de maneira lúdica e inclusiva. Para isso, foram realizadas uma "dinâmica sensorial" para que os estudantes tivessem contato com as hortaliças, a implantação da horta na escola e a visita dos estudantes à universidade para análise das hortaliças e do solo, bem como dos organismos associados à eles. A realização deste projeto permitiu aos graduandos participantes uma experiência didática vivenciada fora da sala de aula convencional, junto a estudantes que apresentavam necessidades educacionais especiais (deficiências cognitivas), sendo enriquecedor para sua formação acadêmica e profissional. As dificuldades apresentadas durante a execução do projeto permitiram aos graduandos a reflexão acerca da educação inclusiva e o desenvolvimento de metodologias de trabalho que permitissem aperfeiçoar o ensino para este público. Observou-se que o projeto foi bem aceito pelo público-alvo, bem como pelos gestores da escola. Ainda, tornou mais evidente aos graduandos a exclusão sofrida pelos estudantes e a necessidade de repensar a educação, considerando as especificidades individuais de cada criança, especialmente aquelas que apresentam deficiências cognitivas.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2025 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.