CACAO GENOTYPIC RESPONSE TO ABIOTIC STRESSES, MANAGEMENT AND SOIL QUALITY AND THE ACQUISITION AND CHARACTERIZATION OF CACAO GERMPLASM
Sustainable Perennial Crops
2011 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 Specific Cooperative Agreement is to provide a mechanism to fund collaborative research on assessment of genotypic differences of cacao and alternate crops to abiotic stresses such as nutrient deficiency/toxicities, drought, and waterlogging. Influence of agroforestry based management systems locally known as Cabruca on performance of cacao and effects on soil quality parameters is being evaluated with Brazilian researchers. This collaborative research project, is conducted with a multidisciplinary team of research scientists from CEPLAC/CEPEC (Comissao Executiva do Plano da Lavoura Cacaueira/Centro de Pesquisas de Cacau) in Itabuna, Bahia, UESC (Universidade Estadual Santa Cruz) in Ilheus, Bahia, Institute of Cabruca, Ilheus, Bahia, the UENF (Universidade Estadual de North Fluminense) Campose, RJ and National Rice and Bean Research Center of EMBRAPA (Empresa Brasileira de Pesquisa Agropecuária ) Santo de Antonio, Goias GO. Beans are useful as an inter crop and cover crop in cacao plantations. Bean genotypes tested showed a range of phosphorous use efficiencies. These findings will be useful to cacao farmers who plant phosphorous efficient bean genotypes to protect soils from erosion and improve the soil fertility and enhance cacao sustainability and yield potentials. Cacao grown under agroforestry systems promotes a continuous deposition of plant residues thereby maintaining high soil organic matter content and affecting soil fauna activities. Findings from five cacao agroforestry systems in Bahia Brazil showed that acidity, and bulk density of soil and polyphenols, and lignin content of tree litter are major factors that control the diversity and richness of soil fauna. Litter management could be a good practice to maintain healthy activities of soil fauna communities to improve production potentials of cacao agroforestry systems. Agroforestry systems adapted for cacao cultivation were evaluated for their impact on organic carbon fractions in the soil. In cacao agroforestry systems higher levels of labile organic fractions were observed in soil surface layers. These systems of cacao management play an important role in efficient nutrient cycling and sequestration of C thereby assisting the mitigation of negative impact of greenhouse effect from CO2. The progress of this agreement was monitored by e-mails and phone or personal communications.