ICAR-Indian Agricultural Research Institute, New Delhi, India.
ICAR-Indian Agricultural Research Institute, Jharkhand, India.
Plant J. 2024 Sep;119(5):2402-2422. doi: 10.1111/tpj.16926. Epub 2024 Jul 11.
Enhancing maize kernel oil is vital for improving the bioavailability of fat-soluble vitamins. Here, we combined favourable alleles of dgat1-2 and fatb into parental lines of four multi-nutrient-rich maize hybrids (APTQH1, APTQH4, APTQH5 and APTQH7) using marker-assisted selection (MAS). Parental lines possessed favourable alleles of crtRB1, lcyE, vte4 and opaque2 genes. Gene-specific markers enabled successful foreground selection in BCF, BCF and BCF, while background selection using genome-wide microsatellite markers (127-132) achieved 93% recurrent parent genome recovery. Resulting inbreds exhibited significantly higher oil (6.93%) and oleic acid (OA, 40.49%) and lower palmitic acid (PA, 14.23%) compared to original inbreds with elevated provitamin A (11.77 ppm), vitamin E (16.01 ppm), lysine (0.331%) and tryptophan (0.085%). Oil content significantly increased from 4.80% in original hybrids to 6.73% in reconstituted hybrids, making them high-oil maize hybrids. These hybrids displayed 35.70% increment in oil content and 51.56% increase in OA with 36.32% reduction in PA compared to original hybrids, while maintaining higher provitamin A (two-fold), vitamin E (nine-fold), lysine (two-fold) and tryptophan (two-fold) compared to normal hybrids. Lipid health indices showed improved atherogenicity, thrombogenicity, cholesterolaemic, oxidability, peroxidizability and nutritive values in MAS-derived genotypes over original versions. Besides, the MAS-derived inbreds and hybrids exhibited comparable grain yield and phenotypic characteristics to the original versions. The maize hybrids developed in the study possessed high-yielding ability with high kernel oil and OA, low PA, better fatty acid health and nutritional properties, higher multi-vitamins and balanced amino acids, which hold immense significance to address malnutrition and rising demand for oil sustainably in a fast-track manner.
提高玉米 kernel 油对于提高脂溶性维生素的生物利用度至关重要。在这里，我们使用标记辅助选择 (MAS) 将 dgat1-2 和 fatb 的有利等位基因结合到四个多营养丰富的玉米杂交种 (APTQH1、APTQH4、APTQH5 和 APTQH7) 的亲本系中。亲本系具有 crtRB1、lcyE、vte4 和 opaque2 基因的有利等位基因。基因特异性标记可在 BCF、BCF 和 BCF 中成功进行前导选择，而使用全基因组微卫星标记 (127-132) 进行背景选择可实现 93%的轮回亲本基因组恢复。由此产生的自交系表现出显著更高的油 (6.93%) 和油酸 (OA，40.49%)，以及更低的棕榈酸 (PA，14.23%)，与原始自交系相比，前维生素 A(11.77ppm)、维生素 E(16.01ppm)、赖氨酸 (0.331%) 和色氨酸 (0.085%) 水平升高。油含量从原始杂交种的 4.80%显著增加到重组杂交种的 6.73%，使其成为高油玉米杂交种。与原始杂交种相比，这些杂交种的油含量增加了 35.70%，OA 增加了 51.56%，PA 减少了 36.32%，而与正常杂交种相比，前维生素 A(两倍)、维生素 E(九倍)、赖氨酸(两倍)和色氨酸(两倍)更高。脂质健康指数显示，MAS 衍生基因型比原始版本具有改善的动脉粥样硬化、血栓形成、胆固醇血症、氧化性、过氧化性和营养价值。此外，MAS 衍生的自交系和杂交种表现出与原始版本相当的籽粒产量和表型特征。本研究中开发的玉米杂交种具有高产能力，具有高 kernel 油和 OA，低 PA，更好的脂肪酸健康和营养特性，更高的多种维生素和平衡的氨基酸，这对于以快速方式解决营养不良和对可持续油的需求上升具有重要意义。
