Pasture, forage and livestock program, annual report for 1992

abonos afrique du nord conduite des herbages crop residues disease resistance engrais estepas farming systems fertilizers fixation de l'azote formation grassland management grasslands herbage hordeum vulgare international cooperation lathyrus ley farming manejo de praderas marginal land medicago middle east moyen orient nematoda nitrogen fixation north africa oriente medio ovin ovinos pastizales pastures pest resistance praderas recherche research residuos de cosechas resistencia a la enfermedad resistencia a las plagas rhizobium rotation culturale rotational cropping selection sheep steppe steppes terre marginale tierras marginales training triticum aestivum triticum durum vicia narbonensis vicia sativa vicia villosa