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

high levels of thermo-tolerance and variability for this trait within these lines. Ten plants were selfed within these
lines during the 2006 rainy season to derive single plant progenies that will be evaluated during the 2007 summer
season at Jodhpur to confirm the within-line variability for this trait and to make selection for higher levels of
thermo-tolerance.
Milestone 5B.5.1.2: Relationship between hybrids and their parental lines for tolerance to high temperatures during
reproductive stage quantified (KNR/RB/VV, 2010)
In the first evaluation attempt, six lines with 30−60% seedset at 46−48°C air temperatures have been identified, with
indication of within-line variability for this trait. The purification of these lines for this trait was initiated, and plans
were developed to screen more lines for thermo-tolerance. Lines with confirmed high levels of tolerance will have
been identified by 2008, and the research on the relationship between parental lines and their hybrids will start in
2009.
KN Rai, Ranjana Bhattacharjee and V Vadez
Salinity trial: A trial was conducted with hybrids made utilizing salinity tolerant and susceptible male sterile lines
and restorer lines, including their parents along with two salinity tolerant populations as checks (GB 8735 and
HHVBC Tall) during rainy season at Patancheru location. All the hybrids flowered in 47−49 days (checks GB 8735
flowered in 45 days and HHVBC Tall in 51 days). None of the hybrids produced significantly superior grain and dry
fodder yields over the checks. However, two hybrids, ICMB 95333 × ICMB 94111 and ICMA 01222 × ICMP 451
gave comparable grain yields of 3413 kg ha -1 and 3400 kg ha -1 respectively, as that of check HHVBC Tall (2958 kg
ha -1 ). Only one hybrid ICMH 451 gave comparable dry fodder yield of 3850 kg ha -1 as that of check GB 8735 (3270
kg ha -1 ). This indicates that hybrids with either one both the parents, tolerant to salinity will give higher grain yields
when compared to hybrids produced by involving susceptible parents.
Hybrid and parental lines of pearl millet (Exp1-2-3-4-5)
A set of tolerant and sensitive inbred parents, along with their respective hybrids were tested under saline controlled
conditions. The large pot system allowed us to evaluate grain and stover yield at maturity. There was no clear
relation between the performance of the hybrids and the performance of its parents. Overall, hybrids performed
better under salinity, reaching an average grain yield of 19.8 g plant -1 , higher than an average 12.2 g for the
inbreds/populations. In fact, we found a very close correlation (r 2 = 0.69) between the grain yield under control and
the grain yield under salinity. This meant that a lager part of the grain yield under salinity was explained by yield
potential. The yield data were then separated into yield as a component and a residual (the latter accounting for the
salinity tolerance per se plus error. These residuals were well related to the grain yield ratio (grain yield under
salinity/grain yield under control). So, both grain yield ratio and residual were used to assess salinity tolerance. The
yield ratio was not significantly different for the hybrids and the inbreds/populations (0.38 and 0.36, respectively).
There were no differences in residuals of hybrids and inbreds/populations either, indicating that hybrid performance
under salinity was likely to be largely due to their yield potential, but partly due to salinity tolerance as well, the
latter not being any greater in hybrids than in the parental lines.
Vincent Vadez, L Krishnamurthy and KN Rai
Milestone 5B.5.1.3: QTL for high temperature tolerance from two diverse mapping populations identified
(KNR/RB/VV, 2012)
Based on the results of activities under above milestone 5B.5.1.2, parental lines of mapping populations will have
been identified by 2009.
KN Rai, Ranjana Bhattacharjee and Vincent Vazed
Output 5C: Germplasm and improved breeding lines with high and stable grain Fe and Zn density in
sorghum and pearl millet made available to specific partners biennially (from 2008) with associated
knowledge and capacity building
MTP Output Target 2006: Existing hybrid parents in sorghum having grain density of Zn above 25 ppm and Fe
above 30ppm available to partners
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