The 2012 ASHS Annual Conference

Most of today’s seedling production uses limited nonrenewable resources and mineral fertilizers that are not approved for use in organic production.  Coir, a bio-product of the coconut industry, and fish emulsion (water soluble fertilizer) are both renewable and approved for use in organic production.  Therefore, this study was conducted to investigate the effect of varying concentrations (based on EC values) of fish emulsion fertilizer on the establishment of sunflower seedlings in coir substrate.  Sunflower seeds were sown in 36 cell trays (3.8 x 2.6 x 5.7 cm) containing coir. They were fertigated with three concentrations of fish emulsion with target EC values of 0.5, 1.0, and 1.5 dS/cm, and conventional fertilizer 20–8.7–16.6 (N–P–K) as a control at 50 mg/L of N.   The nutrient solutions were supplied after the emergence of first set of true leaves.   Fish emulsion concentrations with EC values of 1.0 and 1.5 dS/cm resulted in increasing pH and EC values.  There were no differences in the shoot height and root length among the treatments.  The shoot fresh and dry weights of control plants were greater than that of the plants supplied with fish emulsion.  Fish emulsion concentration with the EC value of 1.5 dS/cm  produced the lowest root fresh weight.  Based on visual index, the control plants appeared robust compared to the fish emulsion supplied seedlings.  However, the root volume of seedlings supplied with 0.5 dS/cm of fish emulsion appeared greater than the control.