Assessment of Calcium Accumulation in the Wheat Aleurone Layer Reveals Phenotypic Variation across Two Distinct Environmental Conditions

Calcium (Ca) is an essential macronutrient with key roles in plant physiology and human health, particularly in bone development and metabolic regulation. In wheat (Triticum aestivum L.), the aleurone layer serves as a nutrient-rich tissue, offering a promising target for calcium biofortification. This study assessed phenotypic variation in calcium accumulation within the aleurone layer across 137 diverse wheat genotypes grown under two contrasting agro-climatic environments: Meerut and Pantnagar. Analysis of variance revealed significant genotypic variation (p < 0.001), while environmental and genotype × environment interactions were non-significant. Calcium concentrations ranged from 127.08 to 392.78 ppm in Meerut and 129.11 to 385.32 ppm in Pantnagar, with grand means of 261.44 ppm and 261.82 ppm, respectively. High estimates of heritability (98.53% in Meerut and 99.53% in Pantnagar) and genetic advance indicated strong genetic control over the trait. These findings highlight stable genotypes with elevated calcium levels that can serve as potential donors for biofortification. The data generated also establish a foundation for future QTL mapping and molecular dissection of calcium regulatory pathways in wheat. This work contributes to the broader goal of developing nutrient-rich wheat cultivars to alleviate dietary calcium deficiency through sustainable crop improvement strategies.