Emerging mechanisms of drought stress tolerance in finger millet for climate resilience

Finger millet commonly known as “ragi” and scientifically known as Eleusine coracana [L.] Gaertn, is a less common cereal but holds abundant nutraceuticals, making it stand out in comparison to commonly consumed major cereals. It stands as the fourth most economically significant millet globally. Consequently, the incorporation of finger millet into diets has the potential to enhance both food security and nutritional well-being in the foreseeable future. As finger millet is cultivated in rain-fed areas under marginal conditions, different stressors have a negative impact on its productivity and yield, particularly in the context of changing climatic conditions. Most frequently occurring abiotic stress like drought will get intensified as a result of the expected rise in global temperatures, variability of rainfall, and lose of soil moisture due to climate change. The regulatory network responsible for drought stress tolerance in finger millet has been investigated through various functional genomics methods, resulting in the identification of potential candidate genes. These genes hold significant promise for enhancing crop improvement programs using transgenic and molecular assisted selection (MAS) approaches. Understanding the molecular and physiological mechanisms under drought stress is needed to breed cultivars that can tolerate different stresses. Therefore, the present review describes the effects of drought stress on finger millet and highlights the recent progress in physiological, biochemical and molecular adaptation of finger millet to drought tolerance. The recent development of drought-tolerant finger millet varieties and progress of genetic modifications are also highlighted.