Nutrient deficiencies of agricultural crops in Papua New Guinea

Alfred Hartemink is a soil scientist at ISRIC in Wageningen. Prior to his current position he was lecturer in soil science at the University of Technology in Papua New Guinea. He holds an MSc in soil science from Wageningen Agricultural University, and has worked as a soil surveyor and soil fertility specialist in Tanzania, Zaire, Indonesia, and for ICRAF in Kenya. Dr Mike Bourke is an Adjunct Fellow in the Research School of Pacific and Asian Studies at the Australian National University. He has been engaged in research on village agriculture in Papua New Guinea for 30 years. He is a specialist in food crop agronomy, agricultural systems and Pacific island village agriculture. He has conducted surveys of village agriculture as well as numerous fertilizer experiments. In Papua New Guinea the population is growing faster than the area under cultivation. As a result, land use is being intensified and soil nutrient depletion may occur, resulting in nutrient deficiencies of agricultural crops. This paper reviews nutrient deficiencies in the agricultural crops of Papua New Guinea using the literature on agronomic trials, expert knowledge and Geographical Information System (GIS) soil fertility databases. One of the aims of this overview is to discuss the spatial distribution of common nutrient deficiencies, which will facilitate the formulation of future strategies on integrated nutrient management research. Nutrient deficiencies have been investigated systematically since the mid-1950s. Research has mainly focused on export tree crops, and relatively little information is available on food crops. Literature analysis and expert knowledge showed consistent trends with deficiencies of B and P in large parts of the highlands. GIS soil fertility databases confirm these observations. The authors’ method has been shown to be useful in delineating areas in which nutrient deficiencies occur, and these findings could be used for the planning of nutrient management research and extension activities.