00263nam a2200097Ia 4500008004100000082002000041100002500061245003500086260003600121300000800157140113s9999    xx            000 0 und d  a631(02)   P1.70  a"Sparks, D. L., ed."  aAdvances in Agronomy - vol. 70  a2000bAcademic PresscSan Diago  a369