Name: KELVIN DE JESUS LEITE
Type: MSc dissertation
Publication date: 12/03/2019
Advisor:
Name |
Role |
|---|---|
| Geraldo Rogério Faustini Cuzzuol | Co-advisor * |
| Paulo Cezar Cavatte | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| Elias Terra Werner | Internal Examiner * |
| Geraldo Rogério Faustini Cuzzuol | Co advisor * |
| Mário Luís Garbin | External Examiner * |
| Paulo Cezar Cavatte | Advisor * |
| Samuel Cordeiro Vitor Martins | External Examiner * |
| Tatiana Tavares Carrijo | External Alternate * |
Summary: Dioic species present distinct ecophysiological traits, a skill that decreases intra-specific competition by the same resource, providing coexistence. This sexual dimorphism is notorious during the reproductive period WHERE, generally, female individuals invest more nutrients and non-structural carbohydrates in the production of fleshy fruits in relation to male individuals, who do not invest in production of fruits. However, altitudinal variations can modify this differential demand for resources between them. In regions with higher altitudes, individuals are exposed to low temperatures, lower atmospheric pressure and higher solar radiation indices, which may impair the accumulation of resources in the leaf tissue, as well as the availability of resources in the soil. The objective of this work was to examine the differential accumulation of nutrients and carbohydrates, considering the effect of sexual dimorphism in eight populations of Myrsine Coriacea located along a gradient altitude in the Atlantic Forest in the state of Espírito Santo. Leaf and soil samples were collected from six female and male individuals from each of the eight populations. Analyses were performed to determine the concentration of nutrients in the soil and the concentration of soluble carbohydrates, starch and nutrients in the leaf tissue. The results showed that sex does not influence the accumulation of carbohydrates and nutrients in the leaf tissue, but the population factor does. The population exposed to higher altitude condition showed higher starch accumulation and lower accumulation of glucose and fructose soluble carbohydrates. On the other hand, the population exposed to the lowest altitude condition presented higher accumulation of glucose and fructose and lower accumulation of starch. The population exposed to higher altitude condition showed higher accumulation of manganese, calcium, iron and magnesium, and low concentrations of nitrogen, phosphorus, potassium and boron, in contrast, to populations exposed to lower altitude that presented higher concentrations of these nutrients. These facts indicate that the limiting conditions imposed by high altitudes, low temperatures for instance, interfere in the accumulation of reserves, such as starch, and in the mineralization of organic matter, decreasing the accumulation of nitrogen, phosphorus and potassium in leaf tissue. differently, the factors sex and population interact and influence the availability of nutrients in the soil of male and female individuals, therefore, the disposition of nutrients in the soil is variable and dependent on sex and the population that the individual is inserted. The populations are inserted in different conditions of altitude, temperature and other abiotic factors, it is understood that a sexual and environmental phenotypic plasticity may exist for the determination of nutrients in the soil. Also, elevated nutrient concentrations in the leaf tissue are linked to a high availability of these nutrients in the soil. The Myrsine Coriacea plants present an environmental phenotypic plasticity for the accumulation of resources in the leaf, this, added to sexual dimorphism, influence the availability of nutrients in the soil among populations exposed to an altitude gradient. Environmental conditions imposed by the environment along the gradient altitude, interfere in the expressing of secondary sexual dimorphism among individuals of the same population, resulting in a similar accumulation of resources between males and females.
