| 1. | It has been suggested that wheat is p - sensitive crop , for combination of n and p could stabilize and improve yield and kernel weight , whereas maize is sensitive to k , for obvious response to combination of n and k ( shuming , 1989 已查明小麦是磷敏感作物,氮磷配合能稳定和改善产量和粒重,而玉米对钾敏感,对氮钾配合反应明显(张漱茗, 1989 。 |