Genetic manipulation of crop plants to enhance integrated nutrient management in cropping systems— 1. Phosphorus: proceedings of an FAO-ICRISAT Expert Consultancy Workshop 15—18 Mar 1994

This Workshop forms part of an overall endeavor to establish a global consortium of researchers focusing their efforts on improving the ability of crop plants to acquire phosphorus, particularly through sources from which it is only sparingly available. These sources include bound forms of soil phosphorus and such fertilizers or amendments as rock phosphate. This volume explains the overall procedures followed, presents the formal papers prepared for the Workshop, and highlights the outcome of the deliberations in the form of a preliminary draft proposal for a global project. A background paper covers the possibilities of favorably manipulating phosphorus acquisition, which include modifying root absorption area by improving rooting characteristics or mycorrhizal associations, manipulating ion absorption mechanisms, and modifying the rhizosphere through root exudations or effects of microorganisms. Position papers prepared by invited specialists examine in detail the prospects for favorable manipulation of specific components of phosphorus acquisition. During the Workshop, research areas with prospects for impact on agriculture in the medium term were identified and appropriate outputs and activities proposed. The promising research areas chosen were modification of root morphology, manipulation of root exudates, enhancement of mycorrhizal effects through crop management practices, and optimization of cropping systems approaches. The Workshop laid the foundation for subsequent activities of formulating detailed project proposals and soliciting support from potential donors for the proposed global consortium.