RA 00110.pdf - OAR@ICRISAT

stress, as well as to genetic differences in tillering.
Poor yield per head was due in part to bird damage,
especially during the 1983 tests in the Sahel Zone
when the recommended date of planting was too
early for these early-maturing cultivars. In addition,
barren heads were frequent in most of the cultivars
tested, for which the causal factors have not yet been
satisfactorily diagnosed.
These results are not final, and further testing of
several of these cultivars in Burkina Faso is warranted.
Nevertheless, several lessons can be learned
from the poor performance. In part, these problems
were due to recommended planting dates which were
somewhat too early and which in a number of sites
led to bird damage. However, in light of the results
from the yield components analysis, (i.e., low plant
stand and low number of heads per plant) delayed
planting dates would not have entirely eliminated
the performance gaps. Moreover, the planting date
inflexibility of photoperiod-insensitive cultivars is
itself a factor contributing to yield instability which
can limit the general adoption potential of individual
cultivars. More importantly the performance
problems also reflect the poor adaptation of the test
cultivars to conditions in farmers' fields. Because all
test cultivars had been selected on the basis of consistent
yield superiority on the research station, these
results suggest that stresses present under the landextensive
management and on the marginal land
types selected by farmers for millet cultivation are
not adequately represented in on-station selection
criteria and screening procedures.
Conclusions
During the last two decades, climatic and demographic
factors have combined to destabilize traditional
farming systems in major portions of the WASAT,
creating increasingly urgent pressures for technical
change. One reflection of these trends is that lower
and more variable rainfall, shorter cropping seasons,
and the gradual expansion of cultivars onto
less fertile and more drought-prone soils have reduced
the suitability of traditional cereal cultivars which
had been selected by farmers under more favorable
conditions. Farmers have become increasingly active
in selecting and experimenting with new cultivars,
often outside formal agricultural extension programs.
To allocate resources efficiently within modern
millet improvement programs, it is clearly desirable
to define goals which correspond to farmers'
changing demands, and which satisfy the most
probable current and future adoption conditions of
specific target groups.
The most common characteristic of new cultivars
demanded by farmers is earlier maturity to fit both
the shorter rainy season and the more shallow soils
into which millet cultivation is expanding. Mediummaturity
millet cultivars maturing 10-30 d earlier
than the most common full-season locals, and with
an important degree of photoperiod sensitivity to
give farmers sufficient planting date flexibility, have
the greatest adoption potential. Well-adapted parent
materials for breeding varieties of these maturity
lengths can come in part from collections of early
local cultivars. Very early, photoperiod-insensitive
cultivars will have very little effect on total production
in all zones unless cropping systems change
radically.
Defining other appropriate objectives requires
consideration of millet's role in the farming systems
of distinct zones. Within the Sahel, where the
extremely harsh environment limits farmers to millet
as their only major cereal, the fundamental problems
are low base yields, extremely low returns and
high risk to new inputs. New cultivars must be more
management responsive if production is to be increased
in this zone. The obstacles and time required
to introduce substantially improved complementary
management in the Sahel however, should not be
underestimated. In a country such as Burkina Faso,
which includes higher potential agroclimatic zones,
and where national resources are extremely limited,
efficiency criteria will continue to lead policy makers
to concentrate extension services and input supplies
in the more humid zones where returns are higher
and more assured. These factors, combined with the
high risk aversion of Sahelian farmers, means that
major management changes using purchased inputs
will come more slowly in the Sahel than elsewhere.
As a shorter-term objective, to ensure that the more
management-responsive cultivars will not increase
farmers' risk, millet improvement programs targeting
that zone should place secondary emphasis on
breeding for improved resistance to the major yieldloss
factors.
The Sudan transition zone and the northern Guinea
savanna pose a different set of problems in defining
appropriate millet breeding goals. More favorable
agroclimatic conditions support highly diversified
cropping systems in which millet generally plays a
particular but subsidiary role in meeting household
food needs. Farmers allocate their resources among
various cereal activities with the goal of efficiently
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