Evaluation of Grain Yields, Pests and Soil Nutrients in Sorghum-groundnut Cropping System in Western Bahr El Ghazal, Warrap and Abyei, South Sudan

Abstract

South Sudan has recurrently experienced severe food shortage and is a net importer of food, mainly cereals from neighboring Uganda, Kenya and Sudan. The main problem is the cereal deficit. The average cereal yield is only about 0.95 ton/ha, which is lower than yields obtained in Uganda, as well as lowest in places with disadvantageous agro-ecological conditions like Ethiopia (3 tons/ha) and Kenya (2 tons/ha). A study was carried out in Western Bahr el Ghazal, Warrap and Abyei in South Sudan to determine the effect of cropping system on sorghum, groundnut and sesame yields. The study was conducted from September to November 2014 and September to November 2015. The counties covered by the study in Western Bahr el Ghazal state included Jur River, Wau and Raga. Counties covered in Warrap state included Gogrial West, stretching to Mading-Achueng and Wunpeeth locations in Abyei area. Data collected included existing cropping systems, planting methods, land preparation methods, seed types and sources, pests, diseases and weed infestation. The data were collected through interviews with farmers using questionnaires and direct observation. Soil samples were collected from five locations of Gogrial West, Udichi, Wau, Mading-Achueng and Wunpeeth. Soil analysis was done for soil reaction (pH), percentage organic carbon (%OC), percentage total nitrogen (%TN), potassium (K), sodium (Na), calcium (Ca) and magnesium (Mg). Grain yields were determined for various cropping systems. Data collected were subjected to analysis of variance and means separated using the least significant difference test at p≤0.05.