Cultivation under pressure: impacts of water restriction and temperature variation on the development of a vulnerable Atlantic Forest orchid

• Grant number: 25/27598-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2026
• End date: March 31, 2027
• Field of knowledge: Agronomical Sciences - Agronomy - Floriculture, Parks and Gardens
• Principal Investigator: Juliana Lischka Sampaio Mayer
• Grantee: Geovanna Cristina Von Zuben
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 22/02667-1 - Ecology and evolution of island plant species: the origin of Ilha de Alcatrazes flora (São Sebastião - SP), AP.PNGP.PI

Abstract

Cattleya guttata Lindl. is an orchid species native to the Brazilian Atlantic Forest and classified as vulnerable to extinction, including a newly discovered population on Alcatrazes Island (São Paulo), whose distribution is restricted to the southeastern Brazilian coast. This population has strong scientific and ecological relevance due to its geographic isolation and potential genetic differentiation. The present project aims to investigate the responses in the interaction between the orchid species and a mycorrhizal fungus (isolated from an adult individual), through morpho-anatomical, proteomic, and physiological analyses of C. guttata under simulated climate-change conditions, considering the presence or absence of the mycorrhizal symbiosis and temperature and water stress. The proposal includes the isolation and characterization of mycorrhizal fungi associated with the roots of adult plants, as well as experiments conducted at different temperatures (25 °C and 30 °C) and levels of water availability (with and without PEG in the culture medium) in asymbiotic and symbiotic conditions. Seedlings at intermediate developmental stages, measuring 1-2 cm, will be evaluated for survival rate, growth, leaf and root number, stomatal density, mesophyll and cuticle thickness. Root and leaf samples will be examined using light, confocal, and scanning electron microscopy, in addition to histochemical tests (Lugol and 3% ferric chloride). Proteomic analyses will be performed to identify mechanisms involved in responses to water and temperature stress, and symbiosis, regarding protein expression. The results may contribute to in situ and ex situ conservation strategies and to the management of threatened populations within the Atlantic Forest, a global biodiversity hotspot. (AU)