Impact of crop rotations and fertilization options on soil chemical and biological properties under cotton farming system in the south-sudanian zone of burkina faso

Cotton is the main cash crop in Burkina Faso and the total cotton acreage is over1/10 of arable land. But, the overall benefit of cotton is negatively affected by decreasing yields due to constant soil degradation. The current study is a contribution to a better understanding of soil biological and chemical properties changes under cotton farming system. To do so, a study was undertaken at Farako-Bâ research stationina split-plot design with crop rotations including cotton in the main plots and fertilization options in the secondary plots. The results showed higher soil organic carbon and nitrogen in rotation “Rice-cotton” plots compared to the other rotations. The results showed also a significant increase in soil phosphorus from 68.57 to 148.76 mg/kg1. However, the level of these nutrients was below the recommended rates to support a good crop production. The soil biological activity was better with the combined application of organic and mineral fertilizers and highest for “Rice-cotton” rotation compared to cotton monoculture. Our results show positive correlation between soil biological activities and soil organic carbon, total nitrogen and soil available phosphorus. The sustainability of the cotton farming system depends highly on suitable combination of good agricultural practices.