Amisorb effects on crop production

Amisorb is the trade name of a polyaspartic acid currently being tested and sold in the Corn Belt by Amilar International. The compound is claimed to act as extensions of plant root hairs, thus allowing plants to more effectively extract nutrients from the soil and produce higher yields. No one at Iowa State University is evaluating Amisorb, but researchers at the University of Illinois (UI) and South Dakota State University (SDSU) have recently done research in the greenhouse and the field.

UI researchers grew wheat in soils with different test levels of phosphorus (P). They observed an increase in wheat yields and P uptake in one soil, but Amisorb had no effect in the other soil. The effect seemed to increase as soil test P increased. They speculated that it may have been due, in part, to soil pH. Yield increases were observed when the soil pH was less than 6.3, but not when they were 6.3 or greater.

Table 1 shows results from a 1996 field study at SDSU by Howard Woodard and recently reported in the Dakota Dirt newsletter. The research involved applying Amisorb to corn, spring wheat, and soybean. The soybean and spring wheat studies included a no-fertilizer treatment with and without Amisorb, and starter fertilizer with and without Amisorb. The corn studies had starter fertilizer with and without Amisorb. Preliminary results indicate that Amisorb had no effect on the yield of any crop.

The results from reported experiments are mixed, which suggests that more research is needed to determine whether economic benefits can be expected from the use of Amisorb.

Table 1. Amisorb effects on corn, soybean and wheat yield in South Dakota, 1996.

Treatment Dawson Granit Prospect Russ
Check 26 36 69 51
Check + 1 qt. Amisorb 27 36 68 49
Starter 111 29 39 70 52
Starter + 1 qt. Amisorb 109 30 40 73 52
Starter + 2 qt. Amisorb 27 39 65 52
Significance for Amisorb NS* NS NS NS NS

This article originally appeared on pages 6-7 of the IC-478 (1) -- February 3, 1997 issue.

Updated 02/02/1997 - 1:00pm