Effects of Lanthanum and Cerium on Chlorophyll Content, Yield and Components of Soybean in Northeast China

In this paper, three soybean varieties with different qualities were used as experimental materials for potted plants. In the seedling stage and the flowering stage, different concentrations of lanthanum and cerium (120, 150 and 180 mg·L^-1 LaCl₃; 30, 60 and90 mg·L^-1 CeCl₃; 30, 40 and 60 mg·L^-1 LaCl₃+30, 40 and 60 mg·L^-1 CeCl₃) were sprayed to study the effects of lanthanum and cerium on soybeans （leaf photosynthetic pigment content, yield and the constituent factors）. The results showed that chlorophyll contents of different qualities soybean leaves reached the maximum under 120 mg·L^-1 LaCl₃ treatment. The yield of high protein soybean was the highest under 60 mg·L^-1 CeCl₃ treatment, the yield of high fat soybean was the highest under 30 mg·L^-1 CeCl₃ treatment, and the yield ofdual-purposesoybeanwasthelargestunder30mg·L^-1CeCl₃treatment.Therefore,thelanthanumandceriumsolutionshadthe effect of"low promotion and high inhibition"on chlorophyll contentof soybeans, and the cerium solution could increase the yields of different quality soybeans.