Herbivory effects on gender functions of Psychotria suterella (Rubiaceae)

• Grant number: 16/18059-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2016
• End date: July 31, 2017
• Field of knowledge: Biological Sciences - Ecology - Theoretical Ecology
• Principal Investigator: Silvana Buzato
• Grantee: Laila Santim Mureb
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Effects of the interaction between herbivores and plants have ecological consequences, as characterized by alterations in the competitive ability of an individual, and evolutionary ones, like changes in gender expression of plants. Several studies have shown that under herbivory plants tend to have decrease in performance of male function, whereas female function is little affected. Under this theoretical context, this study aims to verify by field experiments the consequences of herbivory to gender performance (male and female) of the species Psychotria suterella (Rubiaceae), which exhibits two different floral morphotypes characterized by differential importance in the expression of male and female function. The brevistylous morphotype perform better as the male function associated with high production and dispersal of pollen, while the longistylous morphotype invest more in the production of ovules and development of seeds associated to the female performance. We expect that the effects of herbivory will bring decrease in the production and dispersal of pollen grains in the brevistylous plants but not in the longistylous plants. The possibility of compensation mechanisms by plants to herbivory will be evaluated by phenological behavior (alterations on leaves budding events and leaf senescence). Such results can give additional support to the idea that under environmental changes plants tend to show specialization on gender. (AU)