Soybean (Glycine max L) constitutes an important grain legume crop in semi-arid areas of sub Saharan Africa. The crop yields are usually low and falling relatively due to low P levels of the soil and the inability of the crop to fix nitrogen. Genotypes that make use of P applied to the soil and fix nitrogen could represent a key step in improving the productivity of soybean in the savannah zone.

Drought and soil fertility are some of the major factors limiting crop yield especially in crop legumes. Six on-station trials were conducted to determine nutrients limiting the grain yield and yield component in common beans (Phaseolus vulgaris L.) under drought and non-drought conditions at Kandiyani and Chitedze Research Station. Two trials were conducted at Chitedze Research Station under rainfed conditions: one using a climbing bean variety (MAC 53) and another using bush bean variety (SUG 131).

An experiment was conducted in the Savelugu/Nanton Municipality in the Guinea Savanna zone of Ghana from July 2015 to December 2015 to evaluate the effect of four soybean genotypes and three plant spacing on nitrogen fixation, growth and yield of soybean. The experiment was conducted in a split-plot design and replicated in four different communities. The main plots consisted of four soybean genotypes: TGX 1904-6F, TGX 1955-4F, Soung-pungun and Jenguma. The sub-plots were made up of three plant spacing: 45 by 10 cm, 60 by 10 cm and 75 by 10 cm. Seeds were planted two per stand.

A study was conducted in 2013 at Chitedze Agricultural Research Station to assess the abundance and effectiveness of cowpea rhizobia in soils from different fields and their nodulation capacity by different cowpea genotypes using native cowpea strains. The soils from four fields (Groundnut, Cowpea, Maize and Virgin/non cropped) were used as inoculums including Malawi cowpea inoculant and Australian cowpea inoculant and no inoculation in experiment 1. Highly significant differences (P=0.001) in Rhizobium numbers were observed among the fields.

Soybean genotypes vary in growth characteristics and require different plant densities especially at different ecological zones. It is unacceptable to use one plant spacing recommendation for all varieties in different ecological zones. An experiment was conducted to determine the effect of plant population on the growth, nitrogen fixation and yield of four soybean genotypes (Jenguma, Soung-Pungun, TGX1904-6F and TGX 1955-4F) in the Binduri District in the Sudan Savanna zone of Ghana. The experiment was laid out in a split plot design with four communities serving as replicates.

The study analyzed the determinants of inputs demand and adoption of grain legumes and associated technologies of N2Africa in Kano State. Multi-stage sampling technique was used for the study. Primary data were collected using structured questionnaire. 150 farmers were sampled each from project area and non project area making a total of 300 farmers. The analytical tools employed include descriptive statistics, multiple regression, gross margin analysis and logistic regression.

Understanding factors affecting farmers’ preference for Legume technology adoption is vital for research projects, government agricultural bureau, farmer unions and NGOs’ who are engaged in legume technology distribution to develop appropriate package that farmers are willing to adopt. This study was conducted to analyze factors affecting famers’ adoption preference for chickpea and common bean legume technology in Damot Gale and Boricha District of Southern Region of Ethiopia.