00316nam a2200121Ia 4500008004100000082002000041245003100061260002900092650001300121650001600134650002400150650002000174220204s9999    xx            000 0 und d  a631/635bADV.09 0aAdvances in agronomy. V 09  aNew YorkbAcademicc1957  aAgronomy  aDefoliation  aPhosphorus fixation  aZinc deficiency