Genetic and genomic resources for finger millet improvement: opportunities for advancing climate-smart agriculture

Abstract

Finger millet (FM; Eleusine coracana (L.) Gaertn.) is becoming increasingly vulnerable to various climate-induced stresses, because of which the genetic and genomic resources will be important for improving the crop in the 21 st century. Currently, sizable-untapped genetic resources exists that offer promise for FM improvement to biotic and abiotic stresses. Also, earlier reports elaborate on the potential FM genomic resources, such as molecular markers, genetic maps, and DNA sequence, but the data are scanty to support the efficient and accelerated delivery of the climate-smart FM varieties. This is partly attributable to the delayed availability of complete genome sequence (CGS) of FM. Following the latest developments in FM genomic research, based on the CGS, a diversity of genomic resources have been reported. The review, therefore, provided a detailed analysis on the FM genetic and genomic resourcesaided interventions that could contribute to the three pillars of Climate-smart agriculture (CSA) for addressing FM production challenges under changing climate. Exceptionally, it presented enriched information on additional useful sources of variation within FM genetic resources that have been screened for improving FM tolerance to various climate-induced stresses. Also, it presents the novel opportunities for CSA that could come as a result of the recent availability of CGS data for revolutionizing the development of cutting-edge-molecular breeding tools. Specifically, emphasis was placed on genome-wide-based technologies, such as genomic selection (GS), gene pyramiding, and gene expression with the second-generation genomic biotechnologies, such as TILLING and EcoTILLING that are wanting and have received little attention.

Finger Millet [Eleusine coracana (L.) Gaertn]: An Orphan Crop With a Potential to Alleviate the Calcium Deficiency in the Semi-arid Tropics of Asia and Africa

“…Draft genomes of finger millet were released in 2017 by two groups (Hittalmani et al, 2017;Hatakeyama et al, 2018). Many reviewers have suggested that draft genomes of finger millet will help to improve the finger millet growth and yield through various molecular studies under both biotic and abiotic stress (Ceasar et al, 2018;Vetriventhan et al, 2020;Wambi et al, 2020). Hittalmani et al (2017) identified 330 Ca transporter and accumulation related genes (28 CaM ATPase, 145 CaMK1, 125 CaMK2, 29 CAX1, and 3 TPC1 genes) through transcriptome analysis.…”

“…Finger millet (Eleusine coracana) is a nutrient rich crop. Finger millet is being used as food (grains) in developing countries and as animal feed (straw) in developed countries indicating that it is considered as a poor man's food (Ceasar et al, 2018;Wambi et al, 2020). It is a major crop in the arid and semiarid regions of developing countries of Asia and Africa (Ceasar et al, 2018;Krishna et al, 2018Krishna et al, , 2020.…”

A high‐density linkage map of finger millet provides QTL for blast resistance and other agronomic traits

“…Finger millet is a staple food in semi‐arid, poorer areas with marginal lands, as it has wide environmental tolerances (Kumar et al., 2016; Opole et al., 2018; Talwar et al., 2020). Although currently considered mainly of regional importance, the role of finger millet in global food security is expected to increase because of the growing impacts of climate change, which will likely result in increased drought risk and more erratic weather patterns (Bandyopadhyay et al., 2017; Sultan & Gaetani, 2016; Wambi et al., 2021). Increased health awareness and promotion of finger millet as a ‘smart food’ is also expected to lead to its enhanced consumption (Wangari et al., 2020).…”

“…Although there have been a number of recent advancements in transcriptome (Akbar et al., 2018; Hittalmani et al., 2017; Zhang et al., 2019) and whole‐genome studies of finger millet (Hatakeyama et al., 2018; Hittalmani et al., 2017), modern breeding efforts in finger millet have generally been hampered by the lack of genomic resources and genetic tools (Wambi et al., 2021). Indeed, the majority of finger millet trait studies have been conducted with low numbers of molecular markers and population sizes, yielding poor genomic resolution (e.g., Babu et al., 2014; Ramakrishnan et al., 2016; Ramakrishnan et al., 2017).…”

“…However, a few recent studies have used genotyping‐by‐sequencing (GBS) to develop genetic markers (Puranik et al., 2020; Sharma et al., 2018; Tiwari et al., 2020). Because of the difficulty of generating crosses in finger millet, all trait mapping has thus far been done using association mapping (Wambi et al., 2021). We have previously demonstrated the use of GBS to generate a high‐density genetic map of finger millet in a cross between the wild finger millet [ E. coracana (L.) Gaertn.…”