Proceedings of the Fifth Asian Regional Maize Workshop - Search ...

Table 4.
Distribution of farm sizes in selected countries of Asia, late 198Os.
Average
Farms with
Year farm size < 2 ha
SOUth Asia (ha) (~)
India 1976 2.0 73
Nepal 1981 1.1 84
Pakistan 1980 2.4 37
SOUtheast Asia (ha) (,;)
Indonesia 1983 1.0 85
Philippines 1980 2.8 51
Thailand 1983 4.2 27
SOUrce: IARI (1991).
adopted in other less productive maize-producing areas of the USA, especially the southern
states. Adoption of hybrids was the main factor leading to the takeoff in maize yields
which occurred in the USA during the 1930s, some 20 years before chemical fertilizer and
pesticides were widely adopted (Figure 1). During the late 1940s and early 1950s, hybrid
maize technology spread to other commercial maize producing countries. In Western Europe
and parts of SOUth America where maize is produced under temperate conditions similar to
those found in the USA, adoption of hybrids proceeded rapidly in the post-War years.
Meanwhile, commercial farmers in other regions characterized by warmer, non-temperate
climates also began to take up hybrid maize technology, especially in Eastern Africa
(Kenya), Southern Africa (Zimbabwe), and SOuth America (Brazil). Zimbabwe's commercial
farmers were among the pioneers in the use of single-cross hybrids, extensively adopting
the locally developed hybrid SR 52 during the early 1950s.
During the period when hybrid maizes were first being taken up by large-scale
commercial farmers, efforts were also made to introduce hybrid maize technology into small
farm agriculture in developing countries. Many of these efforts were stimulated by foreign
assistance programs inspired by the success of hybrid maize technology in the USA. Among
the earliest were programs sponsored by the Rockefeller Foundation in Mexico (beginning in
the 194Os) and in India (beginning in the 1950s). In spite of high expectations, these
programs met with limited success, and in most developing countries the proportion of
maize area sown to hybrids remained modest. One major reason for the relative lack of
success in achieving widespread adoption of hybrids was the lack of viable seed industries;
attempts to produce and distribute hybrid seed through public agencies and/or by
means of ad hoc arrangements with private companies generally failed to develop a market
for hybrid seed.
At the time of CIMMYT's establishment in 1965, international maize breeding efforts
were focused primarily on the development of hybrids. However, during the late 1960s the
attention of CIMMYT maize breeders shifted to OPVs. The shift in emphasis from hybrids to
OPVs appears to have been stimulated by several widely held beliefs:
- hybrid seed technology is not appropriate for small farmers, especially since it
requires annual seed purchases
- hybrids cannot succeed without the support of a sophisticated seed industry
- seed of OPVs can be produced with simple technology, and once distributed to
farmers, will travel from farmer to farmer (as had recently occurred with the
high-yielding varieties of rice and wheat)
- improved breeding methods for population improvement offer the opportunity for
OPVs to match yields of hybrids.
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