Radio programs can reach a large group of farmers, but the
type and intensity of disseminated information is rather
limited. Such an intervention might have the largest impact
on awareness. Discussions in association meetings and direct
interactions with agronomists allow to distribute more indepth
and more technical information about new technologies,
albeit to a smaller group of farmers. This does not only
increase awareness, but also farmers’ ability to try the technology,
and hence the likelihood of tryout.
Demonstration trials managed by extension agents further
improve farmers’ ability to apply the technology, reduce
uncertainty about technology attributes, and create certain
expectations about returns. This likely increases the likelihood
of tryout and, in case expectation are met, of continued adoption.
The positive impact of demonstration trials on mineral
fertilizer adoption has been shown by Abdoulaye and Sanders
(2005), in a study on Niger. Depending on the farmers’ own
level of participation in the demonstration trial, this intervention
entails an element of learning-by-doing—in contrast to
radio programs, meetings, and discussions, which are purely
learning-from-others.