Maximizing symbiotic fixation of nitrogen by grain and forage legumes of the tropics : Niftal project, annual report

The contractor maintains over 1,500 strains of Rhizobium and is cataloging isolates from legumes, forages, and tree legumes; 370 cultures were supplied to 26 countries. A serum bank now stocks antisera and gamma globulins for the identification by agglutination of 36 Rhizobium strains. Antisera have been lyophylized and shipped to 21 cooperating researchers. Identification of Rhizobium in oven dried nodules by immunoflourescence and agglutination has also been undertaken. Inoculants are being produced for 14 legumes. Researchers have identified an inexpensive form of yeast extract; a variety of other research has been completed. Other accomplishments included a nitrogen fixation workshop attended by 200 scientists; continuation of the International Network of legume inoculation trials in Asia, Africa, and the Americas; and numerous training and information dissemination activities.