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

Naveen and RTD resistant donors like AC290, AC6078,
LPR 106-19 and CB 98002 and 55 donors were screened
against rice tungro disease under simulated tungro
epiphytotic conditions. Among the cultures CR2654-
17, CR2482-5, CR2482-10, CR2652-14, CR2649-7,
CR2653-16 and CR2647-5 were found to be highly resistant
to RTD. From the segregating generations of eight
crosses, 152 resistant plants were selected. Among the
donors, BJ 1, Purnendu, PTB 18, PTB 21, Pankhari 203,
Chinikamini, Dhusara and AC6029 were found to be
resistant to RTD.
Cultures found to be promising in All India
Co-ordinated Trials
CR2644-2-6-4-3-2 (IET 22117) derived from the cross
of Tapaswini and tungro resistant donor IET 16611
was promoted to AVT-2-IME based on its overall performance
under irrigated mid-early situation. This culture
is moderately resistant to RTD, sheath blight and
brown spot.
CR2652-14 (IET 21346) derived from a cross of
Sarala/CR682-165-1 has shown yield superiority in
AVT 1-SDW trial of AICRIP, 2011 along with moderate
resistance to multiple diseases i.e., RTD, sheath blight,
brown spot, bacterial blight and sheath rot.
CR2643-1-4-3-1 (IET 22118) derived from the cross
between Tapaswini and tungro resistant donor
Vikramarya ranked fourth in Western region in IVT-
IM trial of AICRIP, 2011 and was promoted to AVT-1-
IM.
CR2641-26-1-2-2 (IET 22116) a cross from
Tapaswini/CR101PKT was promoted to AVT2-IME on
the basis of its yield superiority in AVT1-IME trial of
AICRIP, 2011. This variety is moderately resistant to
sheath blight and brown spot. IET 22116 also has
shown good drought tolerant parameters under rainout
shelter at Coimbatore.
CR2647-5(IET 22477) from the cross of Swarna and
tungro resistant donor Vikramarya was promoted to
AVT 1- Late based on its overall performance in IVT-L
trial of AICRIP, 2011.
Three cultures CR2652-14 (IET 21346), CR2656-11-
3-4-2 (IET 21713) and CR2644-2-6-4-3-2 (IET 22117) were
found to be resistant to RTD with low susceptibility
index less than 4.0 in NSN 1 and NSN 2 trial of AICRIP,
2011.
Physiology of Abiotic Stress Tolerance
Mechanism of multiple abiotic stress
tolerance in rainfed lowland rice
Testing of cultivars for submergence tolerance
under different levels of salinity
The experiment was conducted with 10 cultivars,
which differed in submergence as well as salinity tolerance.
Swarna is susceptible to both salinity and submergence,
whereas Swarna-Sub1 is tolerant to complete
submergence. Two cultivars namely Pokkali and
Rashpanjar are tolerant to salinity. The rest of the cultivars
may possess both Sub1 and Saltol QTL. The data
revealed that the cultivars without Sub1 showed susceptibility
under complete submergence. Survival % of
Swarna-Sub1 decreased greatly under greater salinity
(~12 ds m -1 ). Irrespective of salinity of the flood water,
two cultivars namely, IR84649-260-28-1-B and IR84649-
21-15-1-B showed greater survival compared to other
cultivars/fixed breeding lines (Table 14).
Table 14. Survival (%) after 12 days of submergence with different levels of saline water
Normal Saline water Saline water Saline water
Cultivars water (~6 ds m -1 ) (~9 ds m -1 ) (~12 ds m -1 )
Swarna 17 10 10 7
Swarna-Sub1 90 90 58 29
Pokkali (AC39416-A) 20 13 15 4
Rashpanjar 23 13 13 0
IR84649-130-5-1-1-1 100 87 44 14
IR84645-34-9-1-B 95 64 33 7
IR85212-73-1-1-1 40 25 0 0
IR84649-81-4-B-B 100 78 71 20
IR84649-260-28-1-B 100 77 80 67
IR84649-21-15-1-B 100 93 88 62
44 CRRI ANNUAL REPORT 2011-12