Effects of organo-mineral fertilization on plant growth and grain yield of an upland rice variety (NERICA 14) in lower Casamance (South-West Senegal)

Abstract

In Casamance, upland rice is generally practiced on sandy soils very low in organic matter with low yields (1 to 2 tons/ha). The objective of this experiment is to evaluate the effects of different doses of organic and mineral fertilizers on the growth and yield of upland rice. The test was conducted at the ISRA Djibélor station following a Fisher block design with 4 replications. The study factor is organo mineral fertilization with 9 treatments (T1 Unfertilized control; T2 = 0 kg/ha Compost (C) + 100 kg/ha NPK + 75 kg/ha Urea; T3 = 0 kg/ha C + 200 kg/ha NPK + 150 kg/ha Urea; T4 = 2.5 t/ha; T5 = 2.5 t/ha C + 100 kg/ha NPK + 75 kg/ha Urea; T6 = 2.5 t/ha C + 200 kg/ha NPK + 100 kg/ha Urea; T7 = 5 t/ha C; T8 = 5 t/ha C + 100 kg/ha NPK + 75 kg/ha Urea; T9 = 5 t/ha C + 200 kg/ha NPK + 150 kg/ha Urea). The results showed that the tillering is more important with T8 (107 ± 11.49 tillers/m²) and T5 (96.5 ± 24.35 t tiller/m²). The height of the plants is greater with T6 (42.3 ± 2.6 cm) and T9 (62.9 ± 6.0 cm) at booting and with T9 at flowering (92.6 ± 4.3 cm) and maturity stage (98.4 ± 1.5 cm). Paddy grain yield (2,087 ± 1,229 kg/ha) and paddy grain size (28.3 ± 2.9 g/1000 grains) are more influenced by T8. For a sustainable improvement the productivity of upland rice, it is recommended to adopt T8 combination (5 t/ha Compost + 100 kg/ha NPK + 75 kg/ha Urea) for upland rice variety in Southwestern Senegal.