Modeling of carbon assimilation, growth analysis and morphogenesis of two Brachiaria spp. swards under defoliation frequencies with and without irrigation.

• Grant number: 11/17044-5
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: January 01, 2012
• End date: August 31, 2014
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Pastures and Forage Crops
• Principal Investigator: Carlos Guilherme Silveira Pedreira
• Grantee: Ana Flávia Gouveia de Faria
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated scholarship(s): 13/15203-4 - Modeling of carbon assimilation, growth analysis and morphogenesis of two Brachiaria spp. swards under defoliation frequencies with and without irrigation, BE.EP.DR
• Associated research project(s): 13/14767-1

Abstract

The dynamic of forage production is characterized by its growth and senescence indexes during the vegetation period. Both growth and senescence are, among the other factors, influenced by plant physiology process, such as photosynthesis, respiration, and metabolites partitioning in different organs. Photosynthetic activity of forage sward under water deficit and availability may be explained by mathematical modeling, along with other traditional agronomic experimental methods. The objective of the present study is to characterize the photosynthesis of two Brachiaria genotypes (hybrid: CONVERT HD 364 and Brachiaria brizantha (A. Rich.) Stapf cv. Marandu) under harvesting and irrigation management strategies, by comparing forage productivity, analyzing growth index, and morphogenic characteristics to provide insights and understanding of physiological and morphological plant responses to stressed environment. Two parallel field experiments (irrigated and no-irrigated) will be established, in the same time during three years (April 2011-February 2013), in Red-Yellow Oxisol (Hapludox) at ESALQ/USP campus in Piracicaba-SP, Brazil. The layout design will be factorial, encompassing irrigation system (irrigated and no-irrigated), clipping interval (28 and 48 days), and forage genotype. The variables to be measured are morfogenesis characteristics, tiller density, growth, development and senescence, biomass production, leaf area index, light interception by sward, leaf angle, photosynthetic indexes, as well as modeling the CO2 assimilation by forage canopy. All plant variables will be statistical computed, and their means compared by 5%-Tukey text of significance, using SAS program.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

FARIA, Ana Flávia Gouveia de. Morphogenesis and growth analysis of three tropical grasses in response to defoliation frequency. 2014. Doctoral Thesis - Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC) Piracicaba.