Gene Discovery and Advances in Finger Millet [Eleusine coracana (L.) Gaertn.] Genomics—An Important Nutri-Cereal of Future

Abstract

The rapid strides in molecular marker technologies followed by genomics, and next generation sequencing advancements in three major crops (rice, maize and wheat) of the world have given opportunities for their use in the orphan, but highly valuable future crops, including finger millet [Eleusine coracana (L.) Gaertn.]. Finger millet has many special agronomic and nutritional characteristics, which make it an indispensable crop in arid, semi-arid, hilly and tribal areas of India and Africa. The crop has proven its adaptability in harsh conditions and has shown resilience to climate change. The adaptability traits of finger millet have shown the advantage over major cereal grains under stress conditions, revealing it as a storehouse of important genomic resources for crop improvement. Although new technologies for genomic studies are now available, progress in identifying and tapping these important alleles or genes is lacking. RAPDs were the default choice for genetic diversity studies in the crop until the last decade, but the subsequent development of SSRs and comparative genomics paved the way for the marker assisted selection in finger millet. Resistance gene homologs from NBS-LRR region of finger millet for blast and sequence variants for nutritional traits from other cereals have been developed and used invariably. Population structure analysis studies exhibit 2–4 sub-populations in the finger millet gene pool with separate grouping of Indian and exotic genotypes. Recently, the omics technologies have been efficiently applied to understand the nutritional variation, drought tolerance and gene mining. Progress has also occurred with respect to transgenics development. This review presents the current biotechnological advancements along with research gaps and future perspective of genomic research in finger millet.

Carbon and nitrogen isotope variability in the seeds of two African millet species: Pennisetum glaucum and Eleusine coracana

“…Finger millet seeds store well, resisting fungus and insect pests for up to 10 years. These favorable characteristics make E. coracana a highly valuable crop given future climate change, and it is attracting genetic research (e.g., Sood et al).…”

Genome wide association mapping of agro-morphological traits among a diverse collection of finger millet (Eleusine coracana L.) genotypes using SNP markers

“…The availability of SSR markers in finger millet is limited [ 9 , 10 ] and only a few reports are available on association mapping using SSR markers [ 11 – 13 ]. The SNPs are considered to be the ideal markers in plant genetic studies and genome analyses because of their excellent genetic attributes, such as ubiquitous distribution, co-dominant nature of inheritance, chromosome-specific location and high reproducibility [ 14 – 19 ].…”

Finger Millet [Eleusine coracana (L.) Gaertn.] Improvement: Current Status and Future Interventions of Whole Genome Sequence

“…Only preliminary attempts have been made in finger millet for such studies (Supplementary Table S3 ). The recent developments in genomic research are expected to play a key role in the identification and characterization of candidate genes involved in nutrient signaling and transport in finger millet ( Sood et al, 2016 ). As finger millet has 10-fold higher Ca in seeds compared to other cereals, dissection of key genes and signals involved in grain Ca filling will be important for nutrient enrichment of other cereals.…”

“…Finger millet is well known for its exceptionally high calcium (Ca) content having about 0.34% in whole seeds as compared with 0.01–0.06% in most other cereals ( Kumar et al, 2016 ; Gupta et al, 2017 ). The seeds are abundant source of dietary fiber, iron, essential amino acids viz., isoleucine, leucine, methionine, phenylalanine, pytates and trypsin inhibitory factors, and are also gluten-free ( Chandra et al, 2016 ; Sood et al, 2016 ). Finger millet also has many health-promoting benefits such as hypoglycemic, hypocholesterolemic and anti-ulcerative effects ( Chethan and Malleshi, 2007 ).…”