Smallholder farmers in the Guinea savanna agroecological zone of northern Ghana practise maize-grain legume intercropping to mitigate the risks of crop failure in sole cropping, and to safeguard household food, nutrition and income security. The productivity of maize-grain legume intercrops is influenced by soil fertility status and the spatial arrangement of the intercrop components. Although maize-grain legume intercrops have been studied in the Guinea savanna, these have been limited to distinct alternate arrangements on experimental stations.

Common bean (Phaseolus vulgaris L.) and chickpea (Cicer arietinum L.) are the most important grain legumes in Ethiopia. Most of the Ethiopian soils are deficient of soil nitrogen, thereby reducing crop production far below potential. However, common bean (hereafter referred to as “bean”) and chickpea can form symbiotic associations with soil bacteria called rhizobia and fix atmospheric nitrogen inside a root nodule. The fixed nitrogen is then used for growth and development of the plant.

Climbing beans are a new crop for farmers in Kapchorwa district, on the northern slopes of Mt Elgon in Uganda. I assessed the effects of the introduction and expansion of climbing bean cultivation at the farm level: what contribution do climbing bean have to food self-sufficiency and income, and what are trade-offs in terms of investment costs and labour.

Legumes are capable of establishing symbiotic associations with rhizobia in a process called biological nitrogen fixation which is responsible for the wide adoption of legumes as food crops, forages, green manures and in forestry. Recently, the call for the return to a sustainable form of agriculture due to pollution of water body by nitrate and increase in cost fertilizer has caused an increased interest in biological N₂-fixation.

Soyabean (Glycine max L.) is the world’s important food legume of great nutritional value. The crop has the highest protein content (40%) of all food crops and is equivalent to proteins of animal products. The crop holds considerable potential for arresting soil fertility decline and enhancing household food nutrition. Therefore, this study aimed at exploiting soyabean genotypes for yield under Rhizobia inoculation across three locations in the Savanna Region of Nigeria.

Field trials were conducted in 2015 and 2016 seasons to evaluate the response of groundnut (Arachis hypogaea L.) varieties (KAMPALA, KWANKWASO, SAMNUT 21, SAMNUT 23, SAMNUT 24, and SAMNUT 25) to rhizobial inoculation treatments (rhizobium strains NC 92, SBG 234, MJR 518, WDL 129, +N (20 kg N ha^-1), and -N (Control)) in the Sudan and northern Guinea savannas of Nigeria. Results of the 2015 trials were reported in Podcaster 39. The results obtained in 2016 showed similar trends to 2015.