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

decortication, other physical grain characteristics and the degree and amount of Fe and Zn losses in processed grain,
and possibly foods.
HFW Rattunde, M Smit, E Weltzien with IER and HKI
Activity 3.B1.2 Assess opportunities for enhancing human nutrition in sorghum and pearl millet based
cropping systems in WCA
Key sources of variation for micronutrient densities in sorghum and pearl millet identified (2006)
To identify sorghum varieties with high grain iron and/or zinc contents, a set of 90 sorghum varieties adapted to the
Sudanian and Guinean-zones of West Africa were evaluated. The varieties tested included landrace varieties from
Mali and Burkina Faso, accessions from the Guinea-race Core Collection of world-wide origins, and breeding lines
and varieties from ICRISAT and Institut d’Economie Rural (IER) programs in Mali. Three replicate field trials
were conducted on both red (P3b) and black soil (CSd) fields at ICRISAT-Mali in 2005. Although the early end of
the rains resulted in severe drought stress in the black soil field, with later maturing entries producing no grain,
acceptable yields were obtained from the red-soil environment.
Selfed, decorticated grain from each plot of the red-soil environment were analysed for iron and zinc contents at
ICRISAT-India. Decorticated grain was analysed since previous analyses showed decortication reduces
contamination, and, as most grain in West Africa is decorticated for food preparation, it corresponds most closely
with the consumed product. Additional grain characteristics were observed such as pericarp thickness, decortication
yield (10g samples in triplicate in TADD for 3minutes), ease of decortication (visual observation of extent of
decortication with TADD) were also observed.
Varieties showed highly significant variation for iron and zinc contents of decorticated grains (Table 4). The
varieties with the highest iron and zinc contents surpassed the mean by 19%, and 31%, respectively. The entrymean
heritability estimates for iron and zinc are above 0.70, indicating that genetically superior varieties can be
bred. The superiority of these varieties needs to be confirmed however through testing in additional environments.
All of the grain characteristics studied showed highly significant genetic variation, with large genotypic ranges and
high estimates of heritability. However, most of these characteristics showed no correlation with iron or zinc
contents of the decorticated grain. Only decortication yield showed a moderate positive relationship with iron
(r=0.52) and zinc (r=0.58). The high correlation between iron and zinc contents (r=0.84) suggests that the more
highly heritable zinc content may be used for preliminary, indirect selection for iron contents.
Table 4. Mean, range, standard errors and entry-mean heritability estimates for 90 Sorghum varieties tested
in Mali, 2005
Trait Units Mean Minimum Maximum Std Err Heritability
Iron ppm 25.2 19.7 30.0 1.56 0.72
Zinc ppm 15.7 10.5 20.6 1.20 0.80
Pericarp Thickness Score 0(thin)-1(thick) 0.2 0.0 0.8 0.08 0.89
Score 1(easy)-5(most
Ease of Decortication difficult) 1.9 1.0 4.4 0.22 0.91
Decortication Yield % 81.6 63.9 88.2 2.30 0.81
Vitreousness
Score 1(floury) to
9(vitreous) 3.4 1.6 6.7 0.31 0.90
Seed Weight g per 100 seeds 2.4 1.4 3.4 0.11 0.92
HFW Rattunde, EWeltzien and M Smit
Literature review and survey published on importance of sorghum and pearl millet in West-African diets,
with specific reference to micronutrient nutrition (2008).
An internal report and literature review was completed and is being shared with partners before finalizing for a
publication. It is entitled: ‘Evaluation of bio-fortification strategies and introduction of the best means to enhance the
diets of nutritionally disadvantaged populations in developing countries.’
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