Department of Genetics and Plant Breeding, Chaudhary Charan Singh University (CCSU), Meerut, Uttar Pradesh, 250 004, India.
Department of Botany, Chaudhary Charan Singh University (CCSU), Meerut, Uttar Pradesh, 250 004, India.
BMC Plant Biol. 2023 Oct 31;23(1):529. doi: 10.1186/s12870-023-04526-y.
In hexaploid wheat, quantitative trait loci (QTL) and meta-QTL (MQTL) analyses were conducted to identify genomic regions controlling resistance to cereal cyst nematode (CCN), Heterodera avenae. A mapping population comprising 149 RILs derived from the cross HUW 468 × C 306 was used for composite interval mapping (CIM) and inclusive composite interval mapping (ICIM).
Eight main effect QTLs on three chromosomes (1B, 2A and 3A) were identified using two repeat experiments. One of these QTLs was co-localized with a previously reported wheat gene Cre5 for resistance to CCN. Seven important digenic epistatic interactions (PVE = 5% or more) were also identified, each involving one main effect QTL and another novel E-QTL. Using QTLs earlier reported in literature, two meta-QTLs were also identified, which were also used for identification of 57 candidate genes (CGs). Out of these, 29 CGs have high expression in roots and encoded the following proteins having a role in resistance to plant parasitic nematodes (PPNs): (i) NB-ARC,P-loop containing NTP hydrolase, (ii) Protein Kinase, (iii) serine-threonine/tyrosine-PK, (iv) protein with leucine-rich repeat, (v) virus X resistance protein-like, (vi) zinc finger protein, (vii) RING/FYVE/PHD-type, (viii) glycosyl transferase, family 8 (GT8), (ix) rubisco protein with small subunit domain, (x) protein with SANT/Myb domain and (xi) a protein with a homeobox.
Identification and selection of resistance loci with additive and epistatic effect along with two MQTL and associated CGs, identified in the present study may prove useful for understanding the molecular basis of resistance against H. avenae in wheat and for marker-assisted selection (MAS) for breeding CCN resistant wheat cultivars.
在六倍体小麦中，进行了数量性状位点（QTL）和元数量性状位点（MQTL）分析，以鉴定控制对麦长管蚜（CCN）， Heterodera avenae 抗性的基因组区域。使用由 HUW 468 × C 306 杂交产生的 149 个 RIL 作图群体进行复合区间作图（CIM）和包含复合区间作图（ICIM）。
使用两个重复实验鉴定了三个染色体（1B、2A 和 3A）上的 8 个主效 QTL。其中一个 QTL与先前报道的小麦基因 Cre5 共定位，该基因对 CCN 具有抗性。还鉴定了 7 个重要的双基因上位性互作（PVE≥5%），每个互作涉及一个主效 QTL 和另一个新的 E-QTL。利用文献中早些时候报道的 QTL，还鉴定了两个 MQTL，这些 MQTL 也用于鉴定 57 个候选基因（CGs）。其中 29 个 CGs 在根中高表达，编码具有抗植物寄生线虫（PPNs）作用的以下蛋白质：（i）NB-ARC，P 环含 NTP 水解酶，（ii）蛋白激酶，（iii）丝氨酸/苏氨酸/酪氨酸-PK，（iv）富含亮氨酸重复的蛋白质，（v）病毒 X 抗性蛋白样，（vi）锌指蛋白，（vii）RING/FYVE/PHD 型，（viii）糖基转移酶，家族 8（GT8），（ix）小亚基域的 Rubisco 蛋白，（x）具有 SANT/Myb 结构域的蛋白质和（xi）具有同源盒的蛋白质。
本研究中鉴定的具有加性和上位性效应的抗性位点以及两个 MQTL 和相关的 CG，可能有助于理解小麦对 H. avenae 抗性的分子基础，并有助于标记辅助选择（MAS）培育抗 CCN 的小麦品种。
