info:oai:icrisat:3499info:ofi/fmt:xml:xsd:journalKipe-NoltJ AKipe-Nolt, J AAvalakkiU KAvalakki, U KDartP JDart, P JRoot exudation of sorghum and utilization of exudates by nitrogen-fixing bacteriaSoil Biology and Biochemistry0038-0717198517859-8636article