ICRISAT Archival Report 2006 - The seedlings of success in the ...

Comparative performance of hybrids for salinity tolerance: A trial of 30 hybrids along with three checks, viz,
CSH 16, SP 40646 and ICSB 406 was conducted during 2006 rainy season at the Agricultural Research Station
(ARS), Gangavathi to ascertain the salinity tolerance and grain yield in large grain backgrounds. Among them, 16
hybrids with a grain yield range of 4.8 to 6.0 t ha -1 were on par with the hybrid check CSH 16 (6.6 t ha -1 ). For grain
size, 25 hybrids with a range of 2.76 to 3.56 g 100 -1 were comparable with the best check SP 40646 (3.22 g 100 -1 ) in
the saline soil (10 dS m -1 ) at ARS, Gangavathi.
BVS Reddy
Pot-culture trial of parental lines and hybrids: A total of 38 parental lines of sorghum were tested for salinity
tolerance, along with 34 hybrids. There was a large variation among the lines for the grain yield ratio (grain yield
salinity/grain yield control) ranging from 0.022 to 0.536, which is a proxy for salinity tolerance. Most of the
accessions tested appeared to have low ratio, indicating that they were susceptible to salinity. Genotypes ICSB 405,
ICSR 170, ICSR 93034, ICVS 93046, ICSV 745, GD 65115, SP 47513, SP 47519, SP 39105, SP 39053 had high
ratios and were, therefore, tolerant to salinity. Regarding the stover yield ratio (stover yield salinity/stover yield
control), most of the genotypes were in the range 0.40−0.80, showing much less contrast than for yield. There was
no advantage of hybrids over parents in terms of stover yield ratio, which was slightly higher for inbreds than for
hybrids (0.75). The grain yield ratio was also higher for inbred parents (0.20) than for hybrids (0.13). The same was
true for the absolute values of yield under salinity conditions, with average across parents being higher (8.4 g
plant -1 ) than the hybrids (7.4 g plant -1 ). Therefore, it was concluded that sorghum hybrids had no significant
advantage compared to inbreds under saline conditions.
I. Salinity field trial of varieties: We tested promising salinity-tolerant sorghum breeding lines in coastal Orissa.
There was a large range in adaptation of these genotypes to the area, and some varieties such as S 35, ICSV 112,
ICSV 406, ICSR 170, ICSV 93034 were able to reach over 10 t/ha of green fodder yield in saline field over two
cuttings. These data are very promising because it provides potential to have a crop grown after rice in a cropping
system that usually leaves lands fallow after rice harvest, mostly because salinity levels rise during the postrainy
season, which is too high for most crops. Repeat of this testing is planned for 2006−07.
Vincent Vadez, L Krishnamurthy and Belum VS Reddy
Milestone 5B.1.1.2: New F 6 RIL mapping populations for salinity tolerance available for phenotyping and
genotyping (CTH/BVSR/VV, 2009)
From the screening in milestone of breeding lines and parental lines, several suitable parents have been selected and
crosses will be made to develop new RIL for QTL mapping of salinity tolerance.
These crosses are:
BTx 623 (tolerant) × ICSR 93024-1 (sensitive)
ICSV 93046 (tolerant) × S 35 (sensitive)
BTx 623 (tolerant) × S 35 (sensitive)
SP 39105 (tolerant) × ICSR 93024-1 (sensitive).
Vincent Vadez and L Krishnamurthy
Milestone 5B.1.1.3: QTLs for salinity tolerance identified (VV/CTH, 2010)
Salinity screening of parents of existing mapping populations of sorghum: Ten parents (BTx 623, IS 18551,
296B, ICSV 745, PB 15881-3, PB 15520, B 35, E 36-1, N 13, IS 9830) were tested in 2005−06 for salinity tolerance
to examine whether any of these could be used for QTL mapping of salinity tolerance. We found a good contrast for
the grain yield ratio between E 36-1 (0.39) and N 13 (0.13), and also between PB 15220 (0.45) and ICSV 745 (0.10).
However, we did not detect any significant contrasts for the stover yield ratios among the available pairs of parental
lines.
V Vadez
Output target 5B.2: Identification of sorghum genotypes with contrasting root traits (2009)
Activity 5B.2.1: Stay-green QTL introgression lines tested for root traits (VV/CTH, 2009)
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