2008 Annual Report
1a.Objectives (from AD-416)
Develop agroforestry based best management practices, and cover crop technology to improve sustainable cacao and other alternate crop production and assess soil quality factor dynamics and pesticide use and break down in various management systems and evaluate the influence of abiotic stresses on the growth and nutrient use efficiency.
1b.Approach (from AD-416)
Funded and non funded specific cooperative agreements have been established in government and NGO research institutes and universities in the U.S., Brazil, and Peru to carry out glass house and field plot research. The goals of this project are to develop agro forestry based best management practices, evaluate the potential of cover crops, and to assess the changes of soil quality factors that contribute to soil fertility and cacao productivity. Research will be carried in controlled growth conditions to evaluate the influence abiotic factors on growth and nutrient use efficiency of crops, and to evaluate the use and environmental quality impact of pesticides.
Greenhouse and climatically controlled growth rooms were used to assess the net photosynthesis in several selected perennial legume cover crops. The influence of light quality, external carbon dioxide concentration, and aerial temperature on photosynthesis in different legume cover crops (calapo, Jack bean, Mucuna, white lead tree, and Perennial Peanut) was investigated. Legume cover crops used in this study responded differently to changing light quality, external carbon dioxide content, and temperature. Increasing light up to half of the sunlight increased photosynthesis by 11 fold. Field trials have been established with Peru and Brazil to: develop sustainable management of cacao; develop cover crop technology to improve soil fertility and reduce soil erosion losses; understand the implications of agroforestry systems on soil fauna and sequestration of carbon; evaluate agroforestry and non-agroforestry based cacao planting systems on soil quality factors (physical, chemical, and biological). These activities align with component 188.8.131.52 Crop Management Principles of the National Program 304- Crop protection and quarantine. Support the component X Weed management systems (a) cultural and Mechanical control and (c) integrated weed management in Non crop lands and component VI ( c) development of IPM systems.
Soil faunal activities in cacao management systems.
Soil fauna are vital to soil biological processes and their activities are greatly influenced by agroforestry systems used for cacao cultivation. Experiments were conducted in southern Bahia, Brazil to investigate the effects of various agroforestry systems on soil and litter faunal activities and compare these results with faunal activities under natural forest. Faunal activities in agroforestry systems were similar to forested ecosystems. These findings suggest that cacao agroforestry systems offer similar soil environmental conditions to those found in native forests. Increasing mycorrhizae activity and population diversity appears to be an important consideration to reduce the edaphic limitations of soils under cacao. These findings on biological activities will be useful to design sustainable cacao management systems for the Atlantic rainforest region of Brazil. This accomplishment aligns with component 184.108.40.206 Crop Management Principles of the National Program 304-Crop protection and quarantine and its component VI ( c) development of IPM systems.
5.Significant Activities that Support Special Target Populations
The collaborative research established under SCA with ICT (Instituto de Cultivos Tropicales) Tarapoto Peru and Funpab of Ilhéus, Bahia, Brazil are serving as training grounds for many of the regional farmers in best management practices for sustainable cacao production for small landholders of the Andean region of Peru and Atlantic rain forest region of Brazil. These research sites in Peru and Brazil are also helping to support research of Ph. D and MS degree students from national and international universities.
|Number of Non-Peer Reviewed Presentations and Proceedings||5|
Vieira, F.C., He, Z.L., Wislon, P.C., Bayer, C., Stoffella, P.J., Baligar, V.C. 2008. Response of representative cover crops to aluminum toxicity, phosphorus deprivation, and organic amendment. Australian Journal of Agricultural Research. 59:52-6.
Ribero, M.A., Silva, J.O., Aitken, W.M., Machado, R.C., Baligar, V.C. 2008. Nitrogen Use Efficiency in Cacao Genotypes. Journal of Plant Nutrition. 31:239-249.
Baligar, V.C., Fageria, N.K. 2007. Agronomy and physiology of tropical cover crops. Journal of Plant Nutrition. 30:1287-1339.
Fageria, N.K., Baligar, V.C., Zobel, R.W. 2007. Yeild nutrient uptake and soil chemical properties as influenced by liming and boron application in common bean in notilage system. Communications in Soil Science and Plant Analysis. 38:1-17.
Zobel, R.W., Baligar, V.C., Kinraide, T.B. 2007. Fine root diameters can change in response to changes in nutrient concentrations. Plant and Soil Journal. 297:243-254.