A.缺硫 B.缺鎂 C.缺鐵 D.缺硼
A.相對(duì)濕度高,溫度較高 B.相對(duì)濕度低,高溫 C.相對(duì)濕度高,低溫 D.相對(duì)濕度低,低溫
A.大水漫灌,灌透為止 B.經(jīng)常保持干旱 C.小水勤澆 D.都不對(duì)