Glycine max (L.) Merr., ‘Wayne’, was used to study the effects of the antiauxin TIBA (2,3,5‐triiodobenzoic acid) at high levels of fertility in field trials at Urbana, Illinois. The following responses were observed for TIBA treated plants. Leaf area was reduced 20%. Plant height was decreased 33% due to shorter internode lengths. The nitrogen content of leaves and protein content of the seed were decreased; the oil content was unaffected. Pod set increased while the number of seeds per pod decreased. The number of seeds per plant increased, but reduction in seed size caused the total seed yield to remain approximately the same. Standability was improved by TIBA. Large broadcast applications of fertilizers on this highly productive Corn Belt soil did not increase soybean yields. There was also no interaction found for fertility and TIBA.
Synopsis Competition for light was important in the establishment of alfalfa as an intercrop in sorghum. Sorghum was somewhat more competitive than corn with interseeded alfalfa if the distance between rows was 40 inches or less.
