Manjunath Karthik Kumar, Krishna Hari, Devate Narayana Bhat, Sunilkumar V P, Chauhan Divya, Singh Shweta, Mishra C N, Singh J B, Sinha Nivedita, Jain Neelu, Singh Gyanendra Pratap, Singh Pradeep Kumar
Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India.
ICAR-Indian Institute of Wheat and Barley Research, Karnal, India.
Front Nutr. 2023 Feb 10;10:1105207. doi: 10.3389/fnut.2023.1105207. eCollection 2023.
Biofortification is gaining importance globally to improve human nutrition through enhancing the micronutrient content, such as vitamin A, iron, and zinc, in staple food crops. The present study aims to identify the chromosomal regions governing the grain iron concentration (GFeC), grain zinc concentration (GZnC), and thousand kernel weight (TKW) using recombinant inbred lines (RILs) in wheat, developed from a cross between HD3086 and HI1500. The experiment was conducted in four different production conditions at Delhi , control, drought, heat, and combined heat and drought stress and at Indore under drought stress. Grain iron and zinc content increased under heat and combined stress conditions, while thousand kernel weight decreased. Medium to high heritability with a moderate correlation between grain iron and zinc was observed. Out of 4,106 polymorphic markers between the parents, 3,407 SNP markers were used for linkage map construction which spanned over a length of 14791.18 cm. QTL analysis identified a total of 32 chromosomal regions governing the traits under study, which includes 9, 11, and 12 QTLs for GFeC, GZnC, and TKW, respectively. A QTL hotspot was identified on chromosome 4B which is associated with grain iron, grain zinc, and thousand kernel weight explaining the phenotypic variance of 29.28, 10.98, and 17.53%, respectively. Similarly, common loci were identified on chromosomes 4B and 4D for grain iron, zinc, and thousand kernel weight. analysis of these chromosomal regions identified putative candidate genes that code for proteins such as Inositol 1,3,4-trisphosphate 5/6-kinase, P-loop containing nucleoside triphosphate hydrolase, Pleckstrin homology (PH) domains, Serine-threonine/tyrosine-protein kinase and F-box-like domain superfamily proteins which play role in many important biochemical or physiological process. The identified markers linked to QTLs can be used in MAS once successfully validated.
生物强化在全球范围内正变得越来越重要，它通过提高主食作物中的微量营养素含量（如维生素A、铁和锌）来改善人类营养。本研究旨在利用小麦重组自交系（RILs）确定控制籽粒铁浓度（GFeC）、籽粒锌浓度（GZnC）和千粒重（TKW）的染色体区域，这些重组自交系由HD3086和HI1500杂交培育而成。试验在德里的四种不同生产条件下进行，即对照、干旱、高温以及高温和干旱复合胁迫，同时在印多尔进行干旱胁迫试验。在高温和复合胁迫条件下，籽粒铁和锌含量增加，而千粒重下降。观察到中等至高的遗传力，且籽粒铁和锌之间存在中等相关性。在亲本之间的4106个多态性标记中，3407个SNP标记用于构建连锁图谱，图谱长度为14791.18厘摩。QTL分析共鉴定出32个控制所研究性状的染色体区域，其中分别有9个、11个和12个QTL控制GFeC、GZnC和TKW。在4B染色体上鉴定出一个QTL热点，它与籽粒铁、籽粒锌和千粒重相关，分别解释了29.28%、10.98%和17.53%的表型变异。同样，在4B和4D染色体上鉴定出了与籽粒铁、锌和千粒重相关的共同位点。对这些染色体区域的分析确定了推定的候选基因，这些基因编码的蛋白质包括肌醇1,3,4 - 三磷酸5/6 - 激酶、含P环的核苷三磷酸水解酶、普列克底物蛋白同源（PH）结构域、丝氨酸 - 苏氨酸/酪氨酸蛋白激酶以及F - 盒样结构域超家族蛋白，它们在许多重要的生化或生理过程中发挥作用。一旦成功验证，与QTL连锁的已鉴定标记可用于标记辅助选择（MAS）。
