POTASSIUM ALTERNATIVE SOURCES, SUSCEPTIBILITY TO RUST AND WATER USE EFFICIENCY IN PLANTATION OF EUCALYPTUS

• Grant number: 13/14179-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: December 01, 2013
• End date: November 30, 2015
• Field of knowledge: Agronomical Sciences - Forestry Resources and Forestry Engineering
• Principal Investigator: José Leonardo de Moraes Gonçalves
• Grantee: Eric Victor de Oliveira Ferreira
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Eucalyptus is the forest genus most planted in the country, achieving high productivity. However, most of the plantations are in areas of acid and less fertile soils, being fertilization an essential practice to achieve such levels, standing out the K as one of the most nutrient required by eucalyptus. On the other hand, the potassium fertilizers national production is a minority, making necessary importation, mainly of KCl. Thus, arises the need to search alternative sources of the nutrient, as is the case of the K silicates. These also have the Si and, sometimes, Na, elements considered beneficial to plants and that help them in disease control and water loss. The rust (P. psidii) is the main disease of young eucalyptus, causing significant losses in their productivities, and Si can be effective in reducing its incidence. The water supply is appointed as one of the major abiotic factors that interfere on the growth of eucalyptus in the tropics, with emphasis on the water use efficiency (WUE) which can be favored by Si and Na. Thus, this research aims to evaluate the growth, gas exchange, rust incidence and WUE in E. "urograndis" plantation under alternative K sources. It is expected that such sources can replace the KCl fertilization and that there are benefits of the Si and Na on the nutrition, growth, rust control and water efficiency and use in E. "urograndis" plantation grown on less fertile soil of drier region of the São Paulo state.