Effect of Organic and Chemical Fertilizers on the Growth and Diseases of Strawberries <i>(Fragaria </i><i>ananassa</i> var Charlotte)

The intensification of agriculture and the ongoing degradation of soils in the highlands of western Cameroon are compromising the sustainability of vegetable production systems, particularly that of strawberries (<i>Fragaria ananassa</i>), a crop that is increasingly valued in the region. This study aims to evaluate the effect of different types of organic amendments (chicken manure and compost) and mineral amendments (NPK fertilizer) on the growth and health of strawberry plants. The experiment was conducted using a completely randomized block design with six treatments: a control (T0), two doses of chicken manure (20 t/ha, T1; 30 t/ha, T2), two doses of compost (10 t/ha, T3; 20 t/ha, T4) and a chemical treatment (NPK 14-24-14 at 100 kg/ha, T5), each repeated three times. The parameters studied included: vegetative growth (height, leaf area, stolons), incidence and severity of leaf diseases. Pathogens were identified using identification keys and microscopic observations of pure strains obtained on PDA medium. The results revealed that organic amendments significantly improved plant growth. Manure at 30 t/ha (T2) generated the best performance in terms of vegetative growth. However, high-dose treatments (T2, T4) and chemical fertilizer (T5) were associated with a higher incidence of fungal diseases, with <i>Colletotrichum</i> sp., Fusarium sp., and <i>Mycosphaerella</i> sp. identified as the main pathogens. Compost at 10 t/ha stands out as the most effective amendment, combining agronomic performance and disease resistance. The adoption of organic fertilizers could therefore be a significant asset in sustainably improving strawberry production in the highlands of western Cameroon.