Burst^®Yield Booster^®, a plant bioregulator product containing cytokinin, has been evaluated in company sponsored university tests on cotton since 1981. The product has provided an increase in yield at some locations each year that it has been tested. However, the product has not shown yield increases at all locations in any one year. Lack of yield increases at some locations can be explained by weather or other factors that mask or override the benefit of the product to the cotton plant.

Plant mapping experiments were initiated in 1984 to determine how the increase in cotton yield was being achieved. Possible explanations were (1) an increase in fruiting sites; (2) an increase in boll number per plant; (3) an increase in boll size; (4) an increase in turnout of lint. We also had hoped that these plant mapping exercises might assist us in identifying the reasons why the response of the cotton plant to the product might vary under different growing conditions.