I - --ii

Table 4
Effects of Rhizobium inoculation and weed control treatments on nodulation and grain yield
of chickpea and the development of weed biomass at Tel Hadya, 1979-30.
Treatment Nodule Nodule dry wt. Weed biomass Grain yield
No./plant (mg/plant) (kg/ha) (kg/'ha)
Uninoc + Unweeded 5.2 i21.1 5987 1123
Uninoc -: Hand weeded 4.7 190.8 Nil 1947
3889 + Hand weeded 24.7 214.4 Nil 1739
Uninoc + Tribunil 5.8 215.4 593 1322
3889 + Tribunil 17.2 241.7 497 1408
LSD (5%) 2.6 19.4 273 242
Reference
ISLAM, R. 1980. Effect of single, double, and multiple strains of Rhizobium on nodulation'of a
kabuli type chickpea. International Chickpea Newsletter 2:17-18.
Discussion
M.V. Reddy
The reflection of the amount of nodulation in yield in certain genotypes and
not in others indicates a strong genotype and Rhizobium interaciion. If the
contribution of microbiology in crop improvement is to come through, it is in
this area and hence more work should be carried out. The reason for differential
response of genotypes to Rhizobium could be that the genotypes that
respond to inoculation are more efficent in nitrogen use or more responsive to
nitrogen. This can be tested by growing responsive genotypes under nodulefree
conditions in nutrient solution.
R. Islam
You are right. More emphasis has to be given to the host genotype - Rhizobium
strain interaction in future. Existence of non-nodulating cultivars in
chickpeas isyet to be reported. Hence straight comparison of nitrogen fixation
and fertilizer nitrogen use will not be possible at the present moment. However,
evidence is available that some cultivars respond to artificial inoculation
much better than others when native population is low. There it will be more
;nteresting to see whether the yield of the low-yielding cultivars could be
increased by inoculation with the effective strains of Rhizobium.
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