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

Genetic Enhancement of Yield
tions of the country. IET 22298 was top yielder (6.50 t
ha -1 ) followed by IET22314 (5.30 t ha -1 ) and IET 22312
(5.20 t ha -1 ).The mean grain yield ranged from 1.50 to
6.50 t ha -1 . IET 22306 and IET 22312 were observed to
be having high seedling survival and at par with check
varieties, Jalmagna and Dinesh.
Advance variety trial 1-deepwater rice
Seeds of entries under advance deepwater rice trial
were direct seeded during 2011 wet season to evaluate
the promising entries promoted from initial variety trial
tested at different locations of the country. Eleven test
entries were in second year of testing. IET 21719 was
top yielder (5.60 t ha -1 ) followed by IET 21716 (5.10 t ha -
1
). The mean grain yield ranged from 3.00 to 5.60 t ha -1 .
IET 21716 and IET 21706 were observed to be having
high seedling survival and at par with check varieties,
Jalmagna and Dinesh.
Breeding for Flood Prone Ecosystems
Development of varieties for pre-flood (ahu),
post flood (sali) and flash flood situations
Generation of breeding materials
Sixteen uniform lines were selected from F 7
progeny
derived from nine crosses for evaluation in station trial
under rainfed shallow lowland situation. Three hundred
seven F 6
progenies derived from fourteen crosses
were evaluated and a total of 95 uniform lines (27 for
rainfed shallow lowland, 43 for semi deep water and
25 for deepwater ecosystem) were selected for further
evaluation in replicated yield trial. For the development
of pre-flood ahu rice, F 1
s of 16 single crosses (using traditional
ahu rice and early maturing high yielding
bases) were raised during ahu 2011 and 570 single
plants were selected for further evaluation and selection.
Evaluation of pre-flood ahu rice
Twenty four early maturing rice including 10 varieties
received from VPKAS, Almora were evaluated to
assess their suitability as pre-flood ahu crop during ahu
2011. Rice Nilagiri (3.79 tha -1 ), Kalyani-2 (3.67 t ha -1 ),
BAU404-D2 (3.45 t ha -1 ) Kalong (3.10 t ha -1 ) and Anjali
(2.93 t ha -1 ) were the top yielding five genotypes with
similar maturity duration of the local check Luit (2.88 t
ha -1 ). The rice genotypes from VPKAS, Almora were
inferior in grain yield compared to the local check.
Evaluation of post-flood sali rice
Eighteen rice varieties were evaluated during wet
season 2011 under post-flood situation. Twenty five
days old seedlings were transplanted on 9 th September.
CRM49 (2.88 t ha -1 ), Manoharsali (2.62 t ha -1 ),
Dikhow (2.39 tha -1 ) and Dichang (2.35 t ha -1 ) were the
top yielding varieties.
Development of varieties for boro season
Generation of breeding material
One hundred and eighty progenies (in F 4
nursery)
derived from six crosses for development of boro rice
varieties were evaluated during boro 2010-11 and 142
single plants were selected based on plant type, panicle
characteristics and reaction to pest and disease under
field condition. F 2
nursery of another set of 35 crosses
for development of boro rice varieties was also raised
and 390 single plants were selected for further selection
in the next generation.
Preliminary yield trial for boro
Thirty three uniform boro rice cultures were evaluated
during boro 2010-11. Four promising cultures from
the trial (viz., CRL1-1-3-3-1-1-1, CRL1-27-4-3-1-1-3,
CRL2-41-6-3-1-1-1 and CRL2-41-6-3-1-1-13) were nominated
to AICRIP under IVT-Boro.
Germplasm, seed maintenance and genotype
evaluation through national and international
trials
A total of 57 deepwater rice germplasm were collected
from Kamrup, Nalbari, Dhemaji, Lakhimpur,
Sonitpur and Jorhat districts of Assam in collaboration
with NBPGR Regional Station, Thrissur during 2011
wet season. Seven hundred thirty accessions of lowland
rice germplasm during wet season 2011 and 480
accessions of traditional boro rice during boro 2010-11,
were grown and observed for days to 50% flowering,
plant height, EBT and grain yield.
Hybrid Rice Technology
Production and evaluation of test cross hybrids
Five hundred and forty five test crosses involving
seven CMS lines were grown in TCN for evaluation
during dry season and wet season, 2011 and 25 heterotic
combinations with >80% spikelet fertility were
identified besides 30 promising sterile combinations.
Around 300 new test crosses were made and evaluated
in dry season, 2012. Test crosses for some of the fertile
combinations with high spikelet fertility and good yield
potential were repeated and flowering behavior of the
parental lines for synchronization were studied. A few
long duration, short statured plants were selected from
anther culture derived plants of the cross combinations,
CRMS31B/CRMS24B and CRMS32B/CRMS24B and
test crosses were made to develop usable CMS lines in
the late duration.
Maintenance, evaluation and multiplication of
CMS lines
Twelve CMS lines including six CRRI bred CMS lines
were evaluated for agro-morphological and floral characteristics
and were maintained through manual hand
CRRI ANNUAL REPORT 2011-12
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