2012 Annual Report
1a.Objectives (from AD-416):
1. To assess the genotypic differences of cacao and legume cover crops to abiotic stresses such as nutrient deficiency/elemental toxicities, moisture stresses, and shade.
2. Cacao management systems such as agroforestry and cover crops systems and their impact on the soil quality factors will be evaluated.
1b.Approach (from AD-416):
Fundação Pau Brasil actively promotes sustainable cacao production through collaborations with cacao research institutions. This specific cooperative agreement (SCA) will emphasize the coordination of research approaches of the USDA/ARS and all collaborating institution mentioned here and will promote sustainable cacao production research and identification of abiotic stress tolerant cacao germplasms. The agreement promotes international partnerships and cooperation with the USDA-ARS.
The purpose of this agreement is to provide a mechanism to fund collaborative research on Sustainable Production Systems for tropical tree crops. Specific research activities include: assessment of genotypic differences to abiotic stresses such as nutrient deficiencies/toxicities, drought/water logging, and light intensities. Cacao management systems on soil quality and its impact on bean quality are being evaluated. This collaborative research project is conducted with a multidisciplinary team of research scientists from the Comissao Executiva do Plano da Lavoura Cacaueira/Centro de Pesquisas de Cacau in Itabuna, Bahia, Universidade Estadual Santa Cruz in Ilheus, Bahia, Institute of Cabruca in Ilheus, Bahia, the Universidade Estadual de North Fluminense in Campose, RJ and the National Rice and Bean Research Center of Empresa Brasileira de Pesquisa Agropecuária in Santo de Antonio, Goias GO. In greenhouse studies, cacao genotypes subjected to flooding showed a range of tolerance and key plant growth and physiological traits were determined to differentiate flood tolerance. Flood tolerant cacao genotypes will be useful to improve production in lowland areas where flooding is a problem. In other greenhouse studies, 14 cover crops were evaluated for their response to low, medium and high levels of soil phosphorous. Differences among cover crops were observed for growth and phosphorous use efficiency. Such information will be useful to develop cover crop technology to halt soil degradation and to develop sustainable and low input crop management systems for plantation crops. Diversity of tree species and their stand density in a native forestry/cacao agroforestry system called cabruca was investigated. The composition of the dominant trees under this system was strongly influenced by preference of the farmers, particularly when the use was food and lumber. Nitrogen, carbon, and organic phosphorous levels as well as microbial biomass were investigated in soils under cacao agroforestry systems in Bahia, Brazil. Higher levels of mineral composition and microbial activities were observed in the surface soil layers. Agroforestry systems of cacao management play an important role in efficient nutrient cycling there by assisting low input sustainable cacao production.