Root Mass Promotion by A Yeast Stress-Induced Protein and Surfactant Complex in Greenhouse Studies.

Shallow root systems and poor root structure are responsible for reduced photosynthesis and plant biomass, and lower yield, especially during water stress.  Prolific root systems, however, are responsible for accelerated plant growth and may shorten crop development time to harvest because they can extract water from soil layers that are not affected by surface evaporation.  A series of greenhouse studies has demonstrated the ability of yeast stress-induced proteins to promote root production in spinach at very low application rates.  A continuous chemigation of 25ppm (every irrigation cycle) of two formulations based on yeast stress-induced proteins, produced significantly greater root mass (3.9 and 3.5 times/dry weight respectively) 35 days after treatment initiation compared to the control treatment.  The study also exhibited a synergistic effect of a protein/surfactant complex that was significantly more effective than either the surfactant or the protein mixture alone.  In a second study, using a sample that comprised both non-ionic and anionic surfactants, significantly greater root production occurred compared to the control, beginning at day 40 and continued 60 and 90 days after treatment initiation.  In rate response studies using this protein/surfactant formulation at 3, 6, 12, 25, and 50ppm, it was determined that root production was increased beginning at 12ppm continuous chemigation.  Use of these proteins may have significant implications in production agriculture, especially during deficit irrigation or drought stress.