5Pollmer WG,Eberhard D.Klein D.Dhinllon BS.Stueies on maize hybrids in volving inbred lines with varying protein content,zeitschrift Pflanzenzuecht.1978.(80):142-148.
6李妙 刘素恩.中国棉花[J].田间实用技术,2000,27(12):28-35.
7Wo。dson E.Petiole nitrate concentration as an indicator of Geranium nitrogen status.Commum,Soil Sci Anal.1983,(1):1363-372.