Psathyrostachys huashanica Keng (2n = 2x = 14, NsNs) is a valuable genetic resource for wheat improvement because of its high resistance to diseases and high tillering ability. In the present study, a wheat-P. huashanica derived line, designated DH5, was developed. Cytological observations and genomic in situ hybridization analysis suggested that DH5 had a chromosome karyotype of 2n = 42 + Ti (Ti is a small segment chromosome) and that Ti originated from P. huashanica. Ti underwent unequal division in meiotic anaphase I but divided equally in meiotic anaphase II and somatic mitosis. Selfing and backcross results showed Ti could transmitted to offspring through the microspores instead of eggs. Thus, approximately half of the progeny of the DH5 selfing contained one Ti. Molecular methods and fluorescence in situ hybridization confirmed that Ti belongs to P. huashanica 5Ns and that DH5 is a nulli-tetrasome line. Eight pairs of sequence characterized amplified region markers were designed to locate the 5Ns small segment chromosome. Finally, agronomic trait evaluations showed that Ti may not affect DH5 traits, although DH5 produced relatively larger seeds but exhibited relatively shorter plant height. DH5 is a valuable resource for studying the hereditary systems of small segment chromosomes in a wheat background and improving wheat agronomic characteristics.

 华沙草（Psathyrostachys huashanica Keng）（2 n  = 2 x = 14，NsNs）是小麦改良的宝贵遗传资源，因为它具有很高的抗病性和高分till能力。在当前的研究中，开发了小麦-华山P.shanshanica衍生品系，命名为DH5。细胞学观察和基因组原位杂交分析表明，DH5的染色体核型为2 n  = 42 + Ti（Ti是小片段染色体），并且Ti起源于华山对虾。。Ti在减数分裂后期I经历不等分，但在减数分裂后期II和体细胞有丝分裂中均等。自交和回交结果表明，Ti可以通过小孢子而不是卵传播给后代。因此，DH5自交的后代中大约一半包含一个Ti。分子方法和荧光原位杂交证实Ti属于华山松5Ns和DH5是无效的四倍体系。设计了八对具有序列特征的扩增区标记，以定位5Ns小片段染色体。最后，农艺性状评估表明，尽管DH5产生相对较大的种子，但表现出相对较短的株高，但Ti可能不会影响DH5的性状。DH5是研究小麦背景下小片段染色体的遗传系统和改善小麦农艺特性的宝贵资源。