ABSTRACT
Within any production system, actual crop yields are only a fraction of the maximum yields possible. Yield losses represented as the difference between maximum (potential) yields and actual yields are ascribed to various identified and unidentified environmental stresses.1 These environmental stresses are represented by numerous abiotic and biotic factors. Such factors, and the accompanying stresses, are common occurrences within production systems, with essentially all crops being grown under some level, and complex, of environmental stresses. Natural environments are continuously suboptimal with respect to one or more environmental parameters, such as water or nutrient availability.2 The impacts of such stresses on plant growth and crop yields are considerable. Indeed, stresses are estimated to limit overall productivity of U.S. agriculture to as little as 25% of its potential.3
