RA 00110.pdf - OAR@ICRISAT

worthwhile to develop a system for delivering technologies
at the doorstep of these farmers.
Management
Hybrids versus varieties. A l l the released and
recommended hybrids have a grain-yield potential
of around 2000 kg ha* 1 under rainfed conditions
with little or no fertilization (Harinarayana 1985).
However, hybrids have a higher grain-yield potential
than varieties. On the basis of A I C M I P yield
data on released varieties and hybrids, hybrids
should be preferred to improved varieties in the
states of Maharashtra, Uttar Pradesh, Haryana,
Andhra Pradesh, Madhya Pradesh, and Punjab.
The first varieties had lower grain-yield potential
than the hybrids, but newly-released varieties and
varieties not yet released are approaching or exceeding
the grain yield of popular hybrids. Unlike
hybrids, the varieties are self-perpetuating, more
diverse, and less vulnerable to ergot, smut, and
downy mildew.
As a rule, hybrids and improved varieties should
be grown on equal areas to insure high and stable
returns, and reduce the risks from drought and
diseases.
Nitrogen application. Next to quality seed of highyielding
varieties, nitrogen becomes critical, particularly
under drought conditions. Rajasthan, Maharashtra,
Gujarat, and Uttar Pradesh together account
for 76.7% of the area and 68.8% of pearl millet
production in the country. However, the total N, P,
and K consumption of Rajasthan does not exceed 10
kg ha -1 with a total food grain production of less
than 500 kg h a ' ( A I C M I P 1983). Although Maharashtra
(21.2 kg ha -1 ), Gujarat (34.4 kg ha -1 ), and
Uttar Pradesh (49.4 kg ha -1 ) consume more N, P,
and K, the total food-grain productivity is less than 1
t ha -1 , indicating inequitable distribution of fertilizers
between food grains and other crops. As a no- or
low-energy input crop, pearl millet is fertilizerstarved
and fertilizer-hungry, but its response to
fertilizer is tremendous and the grain yield increases
many-fold. Fertilizers should be allocated to rainfed
pearl millet, subsidized to cover any risks, and preferably
applied on a community basis. This is a
necessary "minimum" of dry farming technology if
pearl millet is expected to contribute significantly to
the national food basket.
Managing soil moisture.
Rainfed pearl millet faces
a soil-moisture deficit during grain formation and
seed development. Soil moisture conservation through
grading, land shaping, drainage, erosion control,
etc., is pivotal for the success of any technology. This
often transcends individual boundaries and involves
community and group action. Large scale adoption
requires huge capital investments for equipment and
technical expertise. The necessary infrastructure and
institutional support is often missing in the rainfed
areas.
Collateral hosts for ergot. Natural incidence of
ergot has been observed on Cenchrus ciliaris and
Panicum antidotaJe (Thakur and Chahal 1987).
Cross inoculation studies confirmed their role. Eradication
or deflowering of these graminaceous weeds
requires urgent community action to reduce the
incidence of downy mildew and ergot.
Varietal rotation. Currently a large number of
hybrids and varieties are available for commercial
exploitation. It would be advisable to rotate hybrids
and / or varieties in order to discourage a single genotype
and/or biotype of a particular disease. Varietal
rotation similar to sequence cropping but limited to
the varieties of the same crop prevents the outbreak
of diseases.
Hybrid mixtures. Heterogeneous populations have
a low incidence of disease infection. F, hybrids with
and without disease resistance have been mixed to
combine the twin advantages of high productivity
with low disease incidence. Compared to downy
mildew, ergot, and smut in pure stands, hybrid mixtures
have recorded less infection than either of the
parental hybrids. N H B 3 in pure stand has 44%
downy mildew as against 6, 8, and 11% in combination
with BK 560, CJ 104, and BJ 104. CJ 104 + BK
560 had 1.3% smut as compared to 1.9% in BK 560.
BJ 104 + CJ 104 had comparable ergot incidence as
the parents, but the mixture yielded more grain
(Harinarayana 1982). Early and late hybrids should
be mixed and cultivated widely to elevate grain
yields and minimize disease infection.
Genocropping systems. Hybrid mixtures could adversely
affect the seed industry. Genocropping,
which is intercropping varieties of the same crop in
order to maintain their identity and insure purity,
has been advocated. A genocropping system functions
on the principle of horizontal resistance to
contain disease spread.
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