Using Controlled Release Fertilizer to Increase N Use Efficiency in Commercial Snap Bean Production Applying Center Pivot Irrigation in North Florida

Abstract

Controlled release fertilizer (CRF) is a class of insoluble and granulated fertilizer that releases nutrients such as nitrogen (N) gradually; CRF may reduce nutrient loss through leaching; and hence, CRF may increase crop yield and N use efficiency (NUE). This study was conducted at the University of Florida, IFAS, Suwannee Valley Agricultural Extension Center, Live Oak, FL in Fall 2012. ‘Bronco’ bush snap beans (Phaseolus vulgaris L.) were fertilized with seven N treatments of 0, 40, 80, or 120 lb/acre supplied as either ammonium nitrate (AN) or CRF alone or as combinations of AN plus CRF, arranged in a randomized complete-block design with four replications. The resulting snap bean marketable yields (lb/acre) were: 1) 4697 for 40 AN, 2) 6572 for 8 AN + 32 CRF, 3) 6846 for 80 AN, 4) 7230 for 16 AN + 64 CRF, 5) 8091 for 80 CRF, 6) 7263 for 120 AN, and 7) 8746 for 20 AN + 100 CRF, plus 983 for the 0 N control. The NUE values of the seven N treatments were: 93, 140, 73, 78, 89, 52, and 65 (lb/lb), respectively. The NUE values were significantly greater when the 40 lb/acre and 120 lb/acre N treatments included 80% of the N as CRF. Therefore, use of CRF showed potential to significantly increase snap bean yields and NUE in north Florida.