The influence of soil levels of nitrogen, phosphorus and potassium and methods of application on the growth, quality and nutrient composition of snap beans, Phaseolus vulgaris L

The response of snap beans to high soil levels of nitrogen, phosphorus and potassium, applied by different methods, was evaluated. The factors evaluated were: plant stand, nutrient content of the plants at two weeks after germination and at harvest, yields, pod sieve size distribution, percentage seed, pod color, pod length, pod fiber and nutrient content. A standard band treatment of 40 pounds of N, 80 pounds of P₂O₅ and 40 pounds of K₂O per acre respectively served as the control. Other treatments generally Included multiples of three and six times the standard amount of fertilizer. These other treatments were applied by broadcast and Incorporation over the entire plot area and by similar methods with fertilizer omitted from a six Inch area where seeds were to be drilled. Supplemental narrow bands of small amounts of N and P₂O₅ were also superimposed on two of the treatments with omitted fertilizer areas. As fertilizer amounts Increased plant stand decreased; however, method of application altered the rate of decrease. The yield and nutrient content of snap bean plants were generally not significantly higher when amounts of fertilization exceeded 120 pounds of N, 480 pounds of P₂O₅ and 120 pounds of K₂O per acre respectively. The P and K content of plants at harvest time, resulting from the standard band treatment, indicated these elements may be limiting the growth and development of the plants at this level and method of fertilization. The percentage seed, pod length, pod color, pod fiber content and pod sieve size distribution were not generally significantly differ ent due to treatment.