Effects of Fertilizer Application Rates On Nitrogen Uptake and Nitrogen Use Efficiency of Processing Snap Beans (Phaseolus vulgaris L.).

Effects of fertilizer application rates on nitrogen uptake and nitrogen use efficiency of processing snap beans (Phaseolus vulgaris L.)

Yi Wang¹, Matthew D. Ruark², Amanda J. Gevens³, and Alvin J. Bussan¹

¹Department of Horticulture, University of Wisconsin-Madison, 1575 Linden Dr., Madison, WI 53706

²Department of Soil Science, University of Wisconsin-Madison, 1475 Observatory Dr., Madison, WI 53706

³Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Dr., Madison, WI 53706

Snap beans (Phaseolus vulgaris L.) have two primary uses: processing and fresh market. Wisconsin ranks the first in harvested acreage and yield of processing snap beans. Nitrogen inputs can impact overall snap bean nitrogen uptake and nitrogen use efficiency. Approaches to improve management efficiency for nutrient inputs in snap beans include adjusting fertilizer application rates and selecting newer cultivars. A three-year field experiment was conducted in Plover, WI from 2010 to 2012 to identify effects of supplemental nitrogen applications (0, 45, 90, and 135 kg ha^-1) on nitrogen uptake and nitrogen use efficiency in different processing snap bean varieties. The soil type was Plainfield loamy sand (sandy, mixed, mesic, Typic Udipsamment) averaging 2.5% organic matter with a pH of 6.7, and the sandy soil has a high potential of leaching. Our results showed that nitrogen application was optimized at 90 kg ha^-1 for improved nitrogen uptake in pods of all varieties. Two varieties performed better than the other five varieties due to greater nitrogen use efficiency (agronomic efficiency and crop removal efficiency).