Seed-priming of sorghum with antifungal extracts from Balanites aegyptiaca and Eclipta alba in different agro-ecological zones of Burkina Faso

Seed-priming of sorghum with an aqueous extract from the herbal plant, Eclipta alba has previously been found to increase crop yield of sorghum in Burkina Faso dependent on field location. In the present study, a 2.5% w/v antifungal extract from the desert tree, Balanites aegyptiaca, was similarly shown to increase the yield of sorghum by seed treatment. The effect was compared to the effect of E. alba extract on different types of seeds in different locations. A participatory trial including forty-six fields in three agro-ecological zones was conducted using local, farm-saved seeds. The overall effect on yield conferred by the B. aegyptiaca extract was significantly higher than the effect conferred by the E. alba extract (+31% versus +21%, p<0.03). However, in one zone the opposite hierarchy was observed; also when formally propagated, seeds were used for testing. The same, South-Eastern zone was characterized by poor crop performance despite a relatively high rainfall. Antifungal activity was confirmed in both extracts in vitro and different levels of protection against the pathogen Curvularia lunata were demonstrated in seedlings. The findings are encouraging for a regionally differential use of botanicals in seed treatment and more research to understand local differences in the crop response is suggested. Key words: Bio-priming, sorghum bicolor, emergence, mycoflora, Epicoccum, Fusarium