Exploration of Genetic and Genomic Resources for Abiotic and Biotic Stress Tolerance in Pearl Millet

Abstract

Pearl millet is one of the most important small-grained C4 Panicoid crops with a large genome size (∼2352 Mb), short life cycle and outbreeding nature. It is highly resilient to areas with scanty rain and high temperature. Pearl millet is a nutritionally superior staple crop for people inhabiting hot, drought-prone arid and semi-arid regions of South Asia and Africa where it is widely grown and used for food, hay, silage, bird feed, building material, and fuel. Having excellent nutrient composition and exceptional buffering capacity against variable climatic conditions and pathogen attack makes pearl millet a wonderful model crop for stress tolerance studies. Pearl millet germplasm show a large range of genotypic and phenotypic variations including tolerance to abiotic and biotic stresses. Conventional breeding for enhancing abiotic and biotic stress resistance in pearl millet have met with considerable success, however, in last few years various novel approaches including functional genomics and molecular breeding have been attempted in this crop for augmenting yield under adverse environmental conditions, and there is still a lot of scope for further improvement using genomic tools. Discovery and use of various DNA-based markers such as EST-SSRs, DArT, CISP, and SSCP-SNP in pearl millet not only help in determining population structure and genetic diversity but also prove to be important for developing strategies for crop improvement at a faster rate and greater precision. Molecular marker-based genetic linkage maps and identification of genomic regions determining yield under abiotic stresses particularly terminal drought have paved way for marker-assisted selection and breeding of pearl millet cultivars. Reference collections and marker-assisted backcrossing have also been used to improve biotic stress resistance in pearl millet specifically to downy mildew. Whole genome sequencing of pearl millet genome will give new insights for processing of functional genes and assist in crop improvement programs through molecular breeding approaches. This review thus summarizes the exploration of pearl millet genetic and genomic resources for improving abiotic and biotic stress resistance and development of cultivars superior in stress tolerance.

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

“…Like E. coracana , P. glaucum is able to grow in a wide range of conditions, thriving on as little as 200 mm rainfall up to 1500 mm, and some short duration cultivars are harvestable in just 65–75 days following planting . Recent genetic work has shown that pearl millet exhibits highly significant genetic and agro‐morphologic variation in West Africa and across the varied agro‐climate conditions in which it is cultivated today …”

“…30 Recent genetic work has shown that pearl millet exhibits highly significant genetic and agro-morphologic variation in West Africa 31 and across the varied agro-climate conditions in which it is cultivated today. 32…”

Genomic diversity in pearl millet inbred lines derived from landraces and improved varieties

“…A wide range of genotypic variations are prevalent in pearl millet for various agronomic traits and stress tolerance as a result of its cultivation in diverse agro-climatic conditions and soil types (Shivhare and Lata, 2017). However, a limited amount of germplasm has been exploited in breeding to improve its agronomic traits, stress tolerance, and productivity in pearl millet (Passot et al, 2016).…”

Comprehensive Analysis of NAC Transcription Factor Family in Pearl Millet Uncovers Drought and Salinity Stress Responsive NAC in Pearl Millet (Pennisetum Glaucum)

“…It is a nutritionally superior crop for people living in arid and semi-arid regions of Sub-Saharan Africa and the Indian subcontinent. It can withstand harsh environmental conditions such as drought, salinity and high temperature [1]. Transcriptomic analyses has identi ed functional genes and pathways involved in pearl millets stress response [2][3][4][5][6].…”