Generation and identification of a wheat–Agropyron cristatum (L.) Gaertn. 3P chromosome addition line and substitution line

Abstract

Agropyron cristatum (L.) Gaertn. (2n = 4x = 28, PPPP), which is a wild relative of common wheat and has a P genome, has many excellent characteristics (for example, it is disease-resistant, stress-resistant, and high yielding) and has important utilization values for the genetic improvement of wheat. In this study, the wheat–A. cristatum 3P addition line I-27 and 3P(3B) substitution line I-15 were identified for the first time via in situ hybridization (ISH) and specific molecular marker (EST-STS) from wheat–A. cristatum-derived lines, which are a representative and important material for the utilization of the excellent genes from the A. cristatum chromosome 3P for wheat genetic improvement. In terms of agronomic traits, the tiller number and spike length of the 3P addition line I-27 were significantly higher than those of Fukuhokomugi. The spike length and spikelet number per spike of the 3P substitution line I-15 were significantly greater than those of Fukuho. Additionally, the wheat–A. cristatum 3P substitution line I-15 was resistant to wheat leaf rust. The generation of the 3P addition line I-27 and the 3P substitution line I-15 was essential for the transfer of the excellent genes of the A. cristatum 3P chromosome into common wheat, and resulted in the wheat–A. cristatum addition line containing a complete set of genetic research materials, laying the foundation for comparative studies of the P genome and subsequent fine mapping.