A NEW N INDEX TO ASSESS NITROGEN DYNAMICS IN POTATO (Solanum tuberosum L.) PRODUCTION SYSTEMS OF BOLIVIA

Abstract

"Bolivia is South America’s poorest country, with over 80 % of the rural population under the poverty line and agricultural productivity is closely inversely correlated with poverty in rural Bolivia. Potato (Solanum tuberosum L.) is one of the most important crops for food security in Bolivia, where it is grown with traditional methods, and national-level yields are low. Traditional management of potato involves use of organic amendments (animal manures) to supply N. Enhanced N management has the potential to raise potato yields and reduce rural poverty, yet there is a lack of information about improving nitrogen management practices in potato production areas where traditional systems predominate. A N index for traditional agricultural systems in Bolivia was developed and tested with metadata collected from two of the few studies available for high-altitude systems. The Bolivia N index was able to predict the nitrogen uptake for potato systems at these sites and uptake was correlated with yields (p0.001). Potato responded significantly to N inputs and to total N availability. The Bolivia N index can be used to assess management practices for traditional potato systems and can provide information to farmers and technicians, helping them improve N management to increase yields and food security in Bolivia."