Abstract:

This study was conducted to determine the effect of chicken manure and NPK (17-17-17) fertilizer on growth and yield of carrot (Daucus carota L.) in a volcanic soil of Musanze District in the Northern Province of Rwanda. This was geared upon by many unattended biotic and agronomic factors pertaining to low yields of carrot crop in this area. The treatments were: the control (T0), 10 t ha-1 of chicken manure (T1), 300 kg ha-1 of NPK (17-17-17) fertilizer (T2), and 5 t ha-1 chicken manure + 150 kg ha-1 of NPK fertilizer (T3) and each treatment was in three repetitions. The soil was tested for some of its physical and chemical properties and the soil reaction was moderately acid (pH 5.97) and the quantities of N, P, K were moderate. The growth and yield parameters were studied along with the effect of treatments and the economic contribution of the intervention was determined by Benefit-Cost-Ratio (BGR) approach. Results revealed that the significantly (p < 0.05) highest plant height (45.59 cm) and leaf length (45.29 cm) were obtained in the combination of chicken manure and NPK fertilizer and the lowest were 34.12 and 34.69 cm, respectively, in the absolute control. The sole application of chicken manure and NPK fertilizer recorded plant heights of 43.70 and 39.89 cm and leaf lengths of 43.46 and 39.61 cm, respectively. Results also indicated that marketable root yield was statistically similar between control (5.6 t ha-1) and chicken manure alone (5.7 t ha-1) and between NPK fertilizer alone (8.55 t ha-1) and combination of chicken manure and NPK fertilizer (10.55 t ha-1). The best BCR was obtained in the combination of chicken manure and NPK fertilizer (2.09) compared with the absolute control (1.12), chicken manure alone (1.75) and NPK fertilizer alone (1.62).

Keywords: