On-line version ISSN 1678-4596
PESSOA, Antonio Carlos dos Santos; KELLING, Claudio Renato Schlessner; POZZEBON, Eder João and KONIG, Osvaldo. Nitrogen, phosphorus and potassium concentration and accumulation by black beans under several irrigation levels. Cienc. Rural [online]. 1996, vol.26, n.1, pp.69-74. ISSN 1678-4596. http://dx.doi.org/10.1590/S0103-84781996000100013.
This study was carried out with the objective to determine NPK concentration and accumulation of black beans (Phaseolus vulgaris L., BR Ipagro 1 "macanudo" varie ty) cultivated under different sprinkling irrigation levels. The three irrigation levels were: without irrigation (Wl), irrigation when matric potential reached 80kPa (I-80kPa) and 40kPa (I-40kPa). The results of the flowering sampling indicated that the N concentration (3.72%) was not affected by irrigation levels. Leaf concentration of P in the leaves were different between WI (0.23%) and the irrigated treatments (0.30%). In the maturity stage the N grains concentration changed with irrigation and presented average values of 3.47%. However. P (0.54%) and K (0.89%) grains concentrations were similar. The whole amount of NPK accumulated was different for WI and irrigated treatments. The average values of 62.4 and 123.8kg of N/ha, 8 and 18.8kg of P/ha and 23.7 and 50.7kg of K/ha, were observed for WI and irrigated treatments, respectively.
Keywords : black beans; nutrient concentration; nutrient accumulation; irrigation.