Download Foxtail millet (Setaria italica L.), known for its drought tolerance is

Foxtail millet (Setaria italica L.), known for its drought tolerance is cultivated as a food and
fodder grain crop in arid and semi-arid areas of Asia, Africa and the Americas. It makes an
excellent model crop for investigation due to its close proximity to major cereal crop rice as well
as important biofuel crops such as, switchgrass, napiergrass and pearl millet at genome level
(Devos et al., 1998). In addition, its water use efficiency is higher than that of maize, wheat and
sorghum and its adaptation to dry conditions has been accredited to its relatively small leaf areas,
epidermal cell arrangement, thick cell walls and dense root systems (Li et al., 1997). However,
the molecular mechanisms of its drought adaptation are still not explicable. Molecular dissection
of transcriptional machinery of this crop would assist in this regard. DREB genes activate the
expression of many target genes that are responsible for providing osmoprotection to the plants.
Overexpression of DREB genes has also improved stress tolerance of transgenic plants (Lata et
al., 2011b; Lata and Prasad, 2011). They may play roles in marker-aided breeding also. A
synonymous SNP has been identified (A/G transition) in SiDREB2 gene from contrasting foxtail
millet accessions and an allele-specific marker (ASM) has been developed with the help of
which dehydration tolerant accessions can be selected at a variety of life stages (Lata et al.,
2011a). The ASM is tightly linked with lipid peroxidation (LP) as the SiDREB2 associated trait
contributed to 27.2% of the total variation in LP among the accessions (Lata and Prasad,
unpublished), thus can be considered as a major QTL for dehydration tolerance.
Based on these research backgrounds, I would like to propose cloning and characterization of
various DREB homologs from foxtail millet. The overexpression of these genes in different
heterologous systems would open up new areas of crop improvement through engineering stress
tolerance. I would also propose SNP identification and allele-mining in different foxtail millet
genotypes so that more functional markers could be developed aiding in crop improvement of
foxtail millet and related crops.
References:
Devos KM, Wang Z, Beales CJ, Sasaki T, Gale MD (1998) Comparative genetic maps of
foxtail millet (Setaria italica) and rice (Oryza sativa). Theor. Appl. Genet. 96: 63–68.
Lata C, Bhutty S, Bahadur RP, Majee M, Prasad M (2011a) Association of a SNP in a novel
DREB2-like gene SiDREB2 with stress tolerance in foxtail millet [Setaria italica (L.)]. J. Exp.
Bot. DOI: 10.1093/jxb/err016.
Lata C, Yadav A, Prasad M (2011b) Role of transcription factors in abiotic stress tolerance. In:
Shanker A. (ed) Abiotic Stress/Book2, INTECH Open Access Publishers (Accepted).
Lata C, Prasad M (2011) Role of DREBs in regulation of abiotic stress responses in plants J.
Exp. Bot. (Accepted).
Li Y-M (1997) Drought-resistant mechanism and genetic expression of foxtail millet. In: Li Y-M
(ed) Foxtail millet breeding. Beijing: China Agricultural Press, 433–434.