Effect of irrigation, nitrogen levels and methods of fertilizer application on growth, yield and  profitability of yard long bean [Vigna unguiculata subsp. sesquipedalis (L.) Verdcourt]

A field experiment was conducted during the summer, 2014 at College of Agriculture, Vellayani, Kerala to evaluate the influence of irrigation levels, nitrogen stress and method of application of fertilizers on growth and yield of yard long bean. The experiment consisted of four levels of irrigation, two levels of nitrogen and two methods of application. The results indicated that daily irrigation at 10 mm depth and recommended dose of nitrogen (30 kg ha-1) recorded superior values for growth parameters viz., functional leaves per plant and leaf area index The major yield attributes like number of pods per plant and pod yield per plant and total pod yield were not influenced by levels of irrigation and nitrogen indicating that irrigation once in three days at 20 mm depth and nitrogen level of 22.5 kg ha-1 is sufficient for yard long bean.  Soil and foliar application of nitrogen and potassium recorded superior growth characters, however, the yield was superior when the recommended dose of nutrients were supplied as soil application. Increasing irrigation interval to three days and imparting N stress did not result in any reduction in gross income and net income while, a higher benefit: cost ratio was noted in irrigation at wider intervals.  Soil application of nutrients recorded higher gross income, net income and BCR compared to soil + foliar application.