Floral morphoanatomy of Handroanthus ochraceus (Cham.) Mattos (Bignoniaceae) with a focus on the microstructure of the corolla and secretory structures associated with pollination.

• Grant number: 25/08641-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2025
• End date: July 31, 2026
• Field of knowledge: Biological Sciences - Botany - Plant Morphology
• Principal Investigator: Silvia Rodrigues Machado
• Grantee: Nubia Carolina do Amaral Machado
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Bignoniaceae is a family that stands out for the diversity of floral glands that play a crucial role in the interaction with pollinators. However, studies detailing the morphoanatomy and functioning of the set of secretory structures that co-occur in the flower are still scarce compared to the number of representatives. The objective of this study is to investigate the floral morphoanatomy of Handroanthus ochraceus, a tree species common in dry seasonal environments, pollinated mainly by medium to large-sized bees, focusing on the microstructure of the corolla and the secretory structures associated with pollination. The material will be collected and processed according to usual techniques for analysis in light microscopy and scanning electron microscopy. Additionally, the possible sites producing floral aroma will be analyzed in situ, as well as the volume and concentration of floral nectar. It will be analyzed whether there is a relationship between the structural characteristics of the nectary and the volume and concentration of floral nectar. The results obtained will contribute to expanding knowledge about the morphofunctional diversity of floral glands in the genus Handroanthus and their implications for interactions with pollinators.