Water harvesting technologies and soil conservation measures promote water-nutrient synergy and increase agricultural production in the dryland zones of sub-Saharan Africa. To alleviate water stress, soil fertility decline and reduce runoff, soil and water conservation measures are promising options whose impact on agricultural productivity has not been fully explored. The objective of the study was to assess the effect of using zai pits in combination with selected soil fertility ammendments. An experiment was conducted in Tharaka Nithi County, Kenya to assess effects of using Zai pits in combination with selected amendments on sorghum production. The experiment was set up in a Randomized Complete Block Design (RCBD) involving 12 soil and water conservation treatments with three replications per block. Experimental data were subjected to analysis of variance and mean separation done using least significant difference (LSD) at p < 0.05. Zai pit in combination with tithonia amendment had the highest yields of 4.30 Mg ha −1 during short rains season of 2013 while Zai pit in combination with cattle manure had the highest yield of 4.18 Mg ha −1 during short rains season of 2014. Conventional planting with full rate NPK had the highest benefit-cost ratio (BCR) of 3.58 while Zai pit without input had the least BCR of 0.99. The experiment showed that Zai pit technology contributed to increments of yields in comparison to conventional planting although its BCR was lower than conventional planting with similar amendments. However, both Zai pit and conventional practices should be used in combination with organic and inorganic amendments to enhance yields in sorghum production.

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Food insecurity in Sub-Saharan Africa has prompted a lot of research in the development of soil fertility technologies; however, few of the recommendations from soil fertility management research have been put into use by the target end-users. The objective of the study was to investigate information exchange pathways used by researchers in upscaling of soil fertility in Maara and Mbeere South Sub-counties in Kenya. Structured questionnaires were used to collect information from 22 researchers and 240 farmers. Data was analyzed using descriptive statistics like frequency, mean, and percentages, while Chi-square, Kendal's correlation coefficient was used to test the magnitude of the relationship between dependent and independent variables. Inadequate resources materials and poor networking among stakeholders were among the challenges that the researchers faced in the dissemination of their research outputs. The findings also showed that there was a positive and significant correlation between farm size and the mass media approach. Researchers and extension agents should use a mixed approach; this is the use of combined individual, group, and mass media approaches to cater to the different preferences based on socio-economic characteristics of farmers.