Achieving nutritional security in India through iron and zinc biofortification in pearl millet (Pennisetum glaucum (L.) R. Br.).

The health problems caused by iron (Fe) and zinc (Zn) deficiency plague developing and underdeveloped countries. A vegetarian person mainly depends on cereal based diet with low quantity of Fe and Zn. Biofortification is an economical and sustainable approach to challenge the micronutrient malnutrition problem globally. Pearl millet (Pennisetum glaucum (L.) R. Br.) is one of the nutri-cereals and mostly grown under hot, dry conditions on infertile soils of low water-holding capacity, where other crops generally fail. It contains anti-nutrient compounds like phytic acid and polyphenols which reduce the mineral bioavailability because of their chelating properties. Biofortification of pearl millet is like a double-edged sword which cuts down the economic burden and simultaneously supplies required nutrition to the poor, offering a great scope for food security as well as nutritional security. With this background, this review focus on biofortification of grain Fe and Zn content in pearl millet. Genetic research on Fe and Zn uptake and accumulation in pearl millet grain is crucial in identifying the 'bottlenecks' in biofortification. The review also reveals the need and strategies for increasing bioavailability of Fe and Zn in humans by increasing promoters and decreasing anti-nutritional factors in pearl millet.

Differential Modulation of Heat-Inducible Genes Across Diverse Genotypes and Molecular Cloning of a sHSP From Pearl Millet [Pennisetum glaucum (L.) R. Br.].

The survival, biomass, and grain yield of most of the crops are negatively influenced by several environmental stresses. The present study was carried out by using transcript expression profiling for functionally clarifying the role of genes belonging to a small heat shock protein (sHSP) family in pearl millet under high-temperature stress. Transcript expression profiling of two high-temperature-responsive marker genes, Pgcp70 and PgHSF, along with physio-biochemical traits was considered to screen out the best contrasting genotypes among the eight different pearl millet inbred lines in the seedling stage. Transcript expression pattern suggested the existence of differential response among different genotypes upon heat stress in the form of accumulation of heat shock-responsive gene transcripts. Genotypes, such as WGI 126, TT-1, TT-6, and MS 841B, responded positively toward high-temperature stress for the transcript accumulation of both Pgcp70 and PgHSF and also indicated a better growth under heat stress. PPMI-69 showed the least responsiveness to transcript induction; moreover, it supports the membrane stability index (MSI) data for scoring thermotolerance, thereby suggesting the efficacy of transcript expression profiling as a molecular-based screening technique for the identification of thermotolerant genes and genotypes at particular crop growth stages. The contrasting genotypes, such as PPMI-69 (thermosusceptible) and WGI-126 and TT-1 (thermotolerant), are further utilized for the characterization of thermotolerance behavior of sHSP by cloning a PgHSP16.97 from the thermotolerant cv. WGI-126. In addition, the investigation was extended for the identification and characterization of 28 different HSP20 genes through a genome-wide search in the pearl millet genome and an understanding of their expression pattern using the RNA-sequencing (RNA-Seq) data set. The outcome of the present study indicated that transcript profiling can be a very useful technique for high-throughput screening of heat-tolerant genotypes in the seedling stage. Also, the identified PgHSP20s genes can provide further insights into the molecular regulation of pearl millet stress tolerance, thereby bridging them together to fight against the unpredicted nature of abiotic stress.

Lipase - The fascinating dynamics of enzyme in seed storage and germination - A real challenge to pearl millet.

Pearl millet is considered as 'nutri-cereal' because of high nutrient density of the seeds. The grain has limited use because of low keeping quality of the flour due to the activities of rancidity causing enzymes like lipase, lox, pox and PPO. Among all the enzymes, lipase is most notorious because of its robust nature and high activity under different conditions. we have identified 2180 putative transcripts showing homology with different variants of lipase precursor through transcriptome data mining (NCBI BioProject acc. no. PRJNA625418). Lipase plays dual role of facilitating the germination of seeds and deteriorating the quality of the pearl millet flour through hydrolytic rancidity. Different physiochemical methods like heat treatment, micro oven, hydrothermal, etc. have been developed to inhibit lipase activity in pearl millet flour. There is further need to develop improved processing technologies to inhibit the hydrolytic and oxidative rancidity in the floor with enhanced shelf-life.

Identification of SSR markers associated with seed coat permeability and electrolyte leaching in soybean.

Seed coat permeability and electrolyte leaching are the important traits that have been negatively associated with seed longevity in soybean. The objective of this study was to use SSR markers to identify genomic regions significantly associated with QTLs controlling seed coat permeability and electrolyte leaching in a segregating F2 population derived from a cross of Birsa soya-1 x JS 71-05. Parental polymorphism survey using 145 SSR markers identified 21 polymorphic ones, which were used to genotype 153 F2 individuals. Four independent markers (Satt434, Satt538, Satt281 and Satt598) were significantly (P=0.05) associated with seed coat permeability. One of these markers (Satt 281) also showed significant association with electrolyte leaching that partly supported the observed positive correlation (r = 0.425) between the two traits. Markers for seed coat permeability individually explained 3.9% to 4.5% of the total phenotypic variation, while the marker linked with electrolyte leaching explained 5.6% of the total variation.