Impacts of fertilization on photosynthesis, growth and yield of two soybean cultivars (Glycine maxL. Merr) in Northeast China

Abstract

Soybean ( Glycine max L. Merr) is an important source of protein and oil in human and animal diets in many countries, but information about the interactive effects of fertilization and cultivar on its growth and yield was inadequate. A field experiment was conducted to investigate the effects of three fertilization regimes (CK, NPK, and NPK+manure) and two soybean cultivars, Liaodou14 and Liaodou21, on photosynthesis, growth and yield. NPK and NPK+manure increased leaf area index (LAI) and shoot biomass but did not affect time-course for two cultivars. P N (net photosynthetic rate) of the same treatment in different canopy showed the order of upper canopy > middle canopy > lower canopy. Cultivar, fertilization and the interaction had significant effects on yield of soybean. NPK and NPK+manure increased soybean yield compared with CK, but significant difference among fertilizer treatments was found at Liaodou21 not at Liaodou14 according to Duncan's test. Liaodou14 had significant higher yield than that of Liaodou21 regardless of fertilization application. Liaodou14 also showed consistently lower plant height, more main stem nodes, shorter internode length than that of Liaodou21 regardless of fertilization, which may be contributed to reasonable plant type with high yield in soybean.