This document summarizes a case study conducted in 1943 on the diffusion of hybrid seed corn among farmers in Iowa. The study found that while hybrid seed corn provided significant yields increases, it took farmers an average of 9 years from first learning about the innovation to its full adoption. Farmers progressed through stages of innovation decision making, and relied heavily on interpersonal networks and neighbor experiences to persuade them at different stages. The spread of hybrid corn adoption resembled a "social snowball" effect within the farming communities studied.

1. COLLEGE OF AGRICULTURE , RAICHUR .
DEPARTMENT OF AGRICULTURAL EXTENSION EDUCATION
PRESENTATION
DIFFUSION OF HYBRID SEED CORN
PRESENTED BY
C. VAISHNAVI
M.Sc(Agri.)
PG20AGR12028

2. A CASE STUDY OF THE DIFFUSION OF HYBRID SEED
CORN IN IOWA, USA.
• The diffusion of hybrid seed corn experiment was conducted by
Ryan and Gross in the year 1943.
• It is one of the most influential diffusion studies all the time.
• Although a couple of diffusion studies had been completed
during the 1920’s and 1930’s this study has influenced the
methodology, theoritical frame work and interpretations of later
students in rural sociology tdition and other researrch research
traditions as well

3. BACKGROUND
Hybrid seed corn: Introduced to Iowa farmers in 1928 and
remained as one of the most important agricultural technologies.
- characteristics:
• Increse in production by 20% compared to OPV’s.
• Suitable for mechanical corn pickers.
• More drought resistant.
Because of these characters majority of the farmers adopted it.
Nearly 100% adoption is noticed after 13 years of its release i.e,
1941.

4. • In 1941, Ryan and gross investigated on its diffusion in the area.
• Specifically a Qualitative research was conducted in two
communities in Iowa and a total of the 259 farmers were
interviewed to understand the farmers decision to adopt the
hybrid seed corn.
• Each of the respondents were asked to recall when and how he
had adopted hybrid corn .

5. Most information gathered by interviewing each respondent
about:
• When he decided to adopt the hybrid corn.
• The communication channels he had used at each stage in the
innovation decission process.
• How much of his corn acerage he had planted with the hybrid
seed each year.
• Other information regarding the farmers age, formal education,
farm size, income, tarvel to Des Monies and other cities,
readership of farm magazines and other variables that were
correlated with innovation.

6. by 1933 only 10%
farmers.
by 1936-40% farmers
(took off)
later level off as fewer
farmers are remained.

8. FINDINGS:
Although the hybrid corn was an innovation with a high degree
of relative advantage the innovation decission period from first
knowledge to the adoption decission averaged about 9 years for
all respondents.
• This finding lead to a clear realization that IDP involved
considerable deliberations by most adopters though the
innovation is having spectacular results.
• Average respodent took 3 to 4 years for complete adoption after
planting his first hybrid seed on a small trail plot.
• This study later helped in classifying the 5 stages of IDP.

9. Communication channels played different roles at various
stages in the IDP.
Though the farmer first heard of hybrid seed from a salesmen,
neighbour were the most frequent channel leading to
persuasion.
The research findings suggested the important role of
interpersonal networks in the diffusion process in a system.
The farmer to farmer exchange of personal eperiences with the
use of the hybrid seed seemed to lie at the heart of diffusion.

10. Even though they have not collected much of the sociometric
data regarding the role of diffusion networks and opinion
leadership, Ryan and Gross sensed that the spread of hybrid
corn in the two Iowa communities as a kind of social snowball.
• They wrote: “There is no doubt but that the behaviour of one
individual in an interacting population affects the behaviour of
his fellows. Thus the demonstrated success of hybrid seed on a
few forms offers a changed situation to those who have not
been so experimental. The very fact of acceptance by one or
more farmers offers new stimulus to the remaining ones