Efficient plant regeneration protocol for finger millet [Eleusine coracana (L.) Gaertn.] via somatic embryogenesis

Abstract

In the present study, an efficient protocol for somatic embryogenesis and plant regeneration was established in six finger millet varieties (GBK-043137, GBK-043128, GBK-043124, GBK-043122, GBK-043094 and GBK-043050). Shoot tips from 3 days in vitro grown plants were inoculated on MS supplemented with various concentrations and combinations of α-naphthaleneacetic acid (NAA), 2,4-Dichlorophenoxyacetic acid (2,4-D), benzylaminopurine (BAP) and kinetin for callus induction and somatic embryogenesis. For shoot regeneration, somatic embryos were cultured on various concentrations of BAP, while root induction was done using different concentrations and combinations of NAA, kinetin, BAP and 2,4-D. Acclimatization of regenerated plants was tested using forest soil, cocopeat, manure, sand and fertilizer either singly or in combination. Best callus formation was achieved on 2.5 mg/l of 2,4-D and 1.5 mg/l BAP with a mean of 12.33±0.33 on variety GBK-043128 while shooting and rooting were best on 1.75 mg/l BAP with a mean of 25.07±0.64 and 1.0 BAP+0.25 NAA with a mean of 15.00±2.2, respectively. Best acclimatization was attained using soil, sand and fertilizer on GBK-043094. Plants regenerated were morphologically similar to in vivo plants with 97% survival rate. Moreover, they were fertile and able to set viable seeds. This efficient protocol has the potential for crop improvement and genomic studies.

Finger millet (Eleusine coracana) improvement: Challenges and prospects—A review

“…Eapen and George (1989) reported the first finger millet plant regeneration through somatic embryogenesis. Several studies reported the use of somatic embryogenesis in finger millet (Eapen & George, 1989; Ngetich et al, 2018; Venkatesan et al, 2022), using embryoids for genetic engineering. There are successful finger millet plant regeneration using organogenesis (Mukami et al, 2018; Kansara et al, 2023.)…”

Breeding Strategies and Challenges in the Improvement of Blast Disease Resistance in Finger Millet. A Current Review

“…Previous studies on finger millet have identified several inherent challenges associated with in vitro regeneration, such as the severe recalcitrant nature, polyploidy, and genotypic dependence, which singly or collectively frustrate the plant tissue culture work and, consecutively, the crop improvement systems through transgenesis (Dosad and Chawla, 2016). Plant regeneration in finger millet using different explants in different genotypes has been reported, such as epicotyl (Patil et al, 2009), shoot apical meristem (Babu et al, 2018;Ngetich et al, 2018), mature seeds (Bayer et al, 2014;Pande et al, 2015), and mature embryos (Satish et al, 2016). These protocols provide an opportunity to improve in vitro plant regeneration studies in finger millet, although optimization is required for each genotype.…”