Crop Stubble And Fertilization Continuous Cropping Soybean Plant Height

Effects of crop stubbles and fertilization on the plant heights of continuous cropping soybean was studied by completely random trial in Longzhen Farm in 2003,2004 and 2005. The results of 3 years showed that the plant heights of soybean continuous cropping in alfalfa and maize were all very significantly higher than that of soybean continuous cropping in soybean. Except the results of 2003, the plant heights of soybean continuous cropping in alfalfa were all significantly higher than that in maize. The effects of fertilization on the plant heights of soybean continuous cropping in 2004 and 2005 were very significantly as well, but there was no significant difference between the plant heights of some fertilizing treatments and no fertilizing treatment in some year. Except the results of 2003, the interaction of the crop stubbles and the fertilization on plant heights of soybean continuous cropping had significant and very significant effect. The result of each year indicated that the plant heights of soybean continuous cropping from the combitions of alfalfa stubble and each fertilization treatment were almost higher than that of other two stubbles and each fertilization treatment, the plant heights of soybean continuous cropping from the combitions of soybean stubble and each fertilization treatment were the lowest. The combination of the alfalfa stubble and the compound fertilizer(375 kg/hm2)was the best, the plant height of A1B4 in 2004 was 82.33 cm, higher 5.63㎝(A1B3)～33.36㎝(A3B2)than that of other combinations, the plant height of A1 C7 in 2005 was 84.1 cm, very significantly higher 6.6㎝(A2 C7)-28.9㎝(A3 C6)than that of other 22 combinations. In effect of crop stubbles on the plant heights of soybean continuous cropping, alfalfa stubble superiors to maize, maize stubble superiors to soybean, even though, no any fertilizer in alfalfa stubble, the plant heights of soybean continuous cropping on it for 1, 2 and 3 years were higher than that of almost all combinations of maize stubble and fertilizations for 1, 2 and 3 years; but, significantly or very significantly higher than that of all combinations of soybean stubble and fertilizations for 1, 2 and 3 years. It showed that, under soybean continuous cropping, comparing maize and soybean stubble, alfalfa stubble acted as an effect to increase yields and to decrease fertilizing cost.