Central Rice Research Institute Annual report...2011-12

Natural Resource Management and Input Use Efficiency for Improved Crop
and (iii) P sources (DAP and Purulia rock phosphate)
were integrated for possible additive effects on enhanced
AMF activity mediated efficient P nutrition of upland
rice. In the first rotation (2010 and 2011), AMF inoculum
under partially slow released P condition (DAP
50%+PRP 50%) significantly enhanced AMF population
in soil, mycorrhizal colonization in rice, P uptake
and grain yield in all rotations with highest in maizehorse
gram (1 st yr)/rice (2 nd yr) rotation.
Effects of rainfall pattern on efficiency of
native AMF
Analysis of long term data (6 alternate years between
1999 to 2009) revealed that mycorrhizal advantage to
rice under AM-supportive crop rotation (maize-horse
gram/rice), in terms of P acquisition efficiency (PAE)
was negatively correlated with rainfall amount, indicating
higher mycorrhizal efficacy under moisture
stress. The observation emphasized potential of exploiting
native AM-fungi as climate resilient component technology
in rainfed ecology under present climate change
scenario leading to reducing moisture availability.
Confidence building and facilitation of large
scale use of fly ash as an ameliorant and
nutrient source for enhancing rice productivity
and soil health
Fly ash is a mineral residue resulting from combustion
of coal at high temperature that enters the flue gas
streams. It is particulate in nature, contains most of the
plant nutrients except nitrogen and having higher pH.
Field experiments were conducted to evaluate the efficacy
of bulk application of fly ash (@ 50 and 100 t ha -1 )
either alone or in combination with FYM and inorganic
fertilizers, as soil ameliorant and nutrient source for
rice based cropping system under irrigated (transplanted
and wet direct seeded) and rainfed (dry direct
seeded) conditions from 2010-11 and the residual effects
on rice were studied during 2011-12. The treatments
comprised of different combinations of fly ash,
FYM and chemical fertilizers viz., FP (farmer’s practice
-40:20:0 kg N:P:K ha -1 ); RDF (recommended dose of fertilizer-80:40:40
kg N:P:K ha -1 ); Lime + RDF; FA 50
(Fly
ash @ 50 t ha -1 ); FA 100
(Fly ash @ 100 t ha -1 ); FA 50
+ RDF 75%
+ FYM 25%
(25% of RDF through Farm Yard Manure on
N basis); FA 100
+ RDF 75%
+ FYM 25%
; FA 50
+ FYM @ 12.5 t
ha -1 and FA 100
+ FYM @ 12.5 t ha -1 . As per the treatment
combinations, fly ash and lime were applied and incorporated
manually 20 days before transplanting/
sowing of rice with the help of a spade into the top 15
cm depth of soil during wet season 2010 as one time
application.
The result s revealed that application of fly ash alone
@ 50 t ha -1 and 100 t ha -1 resulted decrease in yield over
farmer’s practice and significantly lower yield than the
100% recommended dose of fertilizers (RDF) under all
three situations. However, application of fly ash @ 50 t
ha -1 along with 75% RDF and 25% through FYM on N
basis has recorded on par yield with that of Lime +
100% RDF under transplanted as well as direct seeded
conditions.
The field demonstrations were conducted in 12 farmers’
fields across three districts of Odisha broadly covering
the major soil groups of the state also revealed
that application of fly ash @ 50 t ha -1 along with 100%
RDF increased the rice yield by 12.9 to 35.4% over the
farmer’s practices across the locations, with an average
of 24.02%.
Wet direct seeded rice crop at maturity stage in different fly ash treated plots
CRRI ANNUAL REPORT 2011-12
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