RA 00015.pdf - OAR@ICRISAT

land-management and supplemental-waterutilization
techniques. Research on improved
practices will be initiated at several locations in
India in addition to that at ICRISAT Center,
and similar activities may be initiated at SAT
locations in West Africa. Investigations (in
cooperation with ICRISAT economists) of the
water balances and water-use efficiencies in existing
small- and medium-scale runoff collection
facilities in Indian villages have begun; the
objectives of these studies is to develop procedures
that will provide a more effective use of
available water. The possibility of involving
other research institutions in this phase of the
program is being explored.
Cropping systems. In the intercropping work, it
is intended to put considerable emphasis on
detailed study of growth and resource use in
combinations of proven advantages, with the
hope that ways in which yield advantages are
achieved may be identified and improved. Detailed
work on plant-population effects will
continue, and genotype studies will be increased,
hopefully to include all the ICRISAT crops. In
the sequential and relay cropping studies, comparisons
of maize and sorghum as rainy season
crops will continue; postrainy season crops will
be limited to chickpea, pigeonpea, and sorghum.
Sorghum genotypes will be screened for
ratoonability.
In cropping systems entomology, larger plots
will be used to provide a more-realistic "field"
situation that will permit regular sampling without
seriously affecting population levels. Pestparasite
surveys in farmers' fields will be expanded.
With the indications that some insecticide
sprays may still be needed in intercropping
situations, a prime objective of this phase of our
work will be development of integrated pestmanagement
systems. Importance of plant type,
plant populations, and spacing will be further
studied.
Collaboration with organizations-such as
COPR, Boyce Thompson Institute, and CIBC -
on the possibility of biological and viral control
of Heliothis is being discussed and a survey of
biological and microbiological agents on this
insect in India is planned for the coming season.
Plans for establishing a trap grid throughout the
subcontinent so as to study migratory behavior
of H. armigera in India will hopefully mature.
Agronomy and weed science. Further studies to
determine the effects of different crop combinations,
sequences, geometries, and genotypes,
along with other physical, biological, and cultural
factors on weed growth are planned. In the
crop-oriented weed research, the major emphasis
will be to determine growth characteristics responsible
for weed competitiveness and to study
the differential tolerance of different cultivars of
ICRISAT crops to commonly used herbicides. In
addition to the field trials at ICRISAT Center,
observations in a few selected villages are planned
to measure the success of farmers' own weedcontrol
methods and to assess the payoffs of
additional weed control over the existing system.
This effort will help to develop an understanding
of the crop, soil, climatic, and social situations in
which improved weed management could have
the greatest impact.
A minimal forage-crop program is being initiated
to evaluate forage grass and legume
mixtures as to their yield of palatable forage, soilerosion
control, longevity through hot and dry
seasons under heavy grazing pressure, and rapidity
of regrowth at the onset of the rainy
season. These features are important for
management of grassed waterways and tank
bunds. The "Steps in Improved Technology"
experiment will be continued with sorghum on
Vertisols and pigeonpea/pearl millet intercrop on
Alfisols.
W a t e r s h e d - b a s e d
R e s o u r c e U t i l i z a t i o n
R e s e a r c h
The watersheds described in Table 64 represent
ICRISAT's field laboratory for "systems research."
Here the concept of a watershed-based
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