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

during the ongoing off-season. Genotyping of representative sets of pearl millet and sorghum germplasm has started
in collaboration with the BECA in Nairobi, Kenya.
For the first time in 2005 and again in 2006 all interested partners in the different WCA countries have been able to
test a range of the new guinea race sorghum hybrids. Results confirm consistently high levels of heterosis, especially
for the Sudanian zone. Specific parents with high combining ability are starting to be become apparent, as well some
patterns for high heterosis for grain productivity.
More detailed testing of grain yield heterosis is well underway, with the second season of data presently being
analysed. In addition, 5 new guinea race hybrids and a local guinea race control, CSM 335, are being evaluated at
3 plant densities (67, 133 and 200,000 plants/ha) to confirm the results of yield potentials and grain yield
components obtained in 2005. A sufficiently high rate of mineral fertilizers was applied to assess biomass and grain
yield potentials of these hybrids.
The development of new hybrid parents of guinea race sorghum is advancing as planned. Thirteen new lines of
diverse backgrounds and grain yield components have reached the BC6 stage of transfer into the male-sterility
inducing cytoplasm. Seed of the lines developed earlier have been multiplied, and been made available to partners
on request. For pearl millet a set of inbred lines representing the entire range of diversity from WCA is under
development to initiate the process of parental line development parallel to the identification of heterotic groupings.
Activity 3A2.1: Multi-location evaluation of 100 pearl millet factorial crosses and their parental populations
at 6 locations across WCA to study the effect of geographic and/or morphological distances of the parental
populations on heterosis in pearl millet population crosses.
Milestones: At least 2 superior population crosses per partner country and agro-ecological zone identified and
entering participatory recurrent selection programs (2007)
Field trials of a factorial design crossing involving 20 different parental populations from the five countries were
evaluated at 7 locations (1 Senegal, 2 Mali, 1 Burkina Faso, 2 Niger, 1 Nigeria) during the RS 2006; and data entry
and analysis are underway. Farmer and breeders performed visual selections that will enter into the overall analysis.
BIG Haussmann
Published article on combining ability patterns of WCA pearl millet landraces (2008)
The data from above trials will serve as a basis for this publication.
BIG Haussmann
Activity 3A2.2: SSR Genotyping of 250 pearl millet and 210 sorghum accessions for heterotic grouping
Milestone: Results on use of markers for assessing heterotic groups published (2008)
The sorghum and pearl millet accessions were selected from the germplasm collections evaluated for use in WCA,
and for sorghum, including accessions and varieties in use in current hybrid breeding. Seed of selected accessions
was sent for marker analysis.
BIG Haussmann and HFW Rattunde
with University of Hohenheim
Activity 3A2.4: Heterosis in Guinea-race sorghum hybrids assessed
Milestone: 2006: Regional Hybrid trials provided to WCA collaborators
A total of 91 experimental sorghum hybrids (based Guinea or inter-racial A lines crossed with Guinea male-parents)
were produced and distributed as observation nurseries in 2006 for evaluating fertility restoration and agronomic
desirability of hybrids per se and relative to the adjacent male-parent. These nurseries were provided to IER-Sotuba
and INERA-Saria.
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