Lolium multiflorum is a crosspollinated plant,there must have the mixtures in hybridizations.The discrimination of true and false hybrids is necessary.The study aimed to select excellent hybrid combinations and progenies,and provided the essential data for the subsequent cross breeding.Parental cultivars we choose were the international good varieties and the leading varieties in southwestern Sichuan.Five parental cultivars of Lolium multiflorum and five cross combinations were used to identify their true hybrids by SSR molecular markers.The SPSS computer software was used to analyze the data to differentiate the differences between parents and progenies on morphological characteristics.The results were as followed:(1) 20 primer pairs produced 426 polymorphic bands with average percentage of polymorphism of 82.41％,each pair of primers amplified 25.9 bands on average,and 21.3 bands had polymorphism on average.Samples had relatively high molecular genetic polymorphisms so it was feasible to identify the parents and hybrids.(2) The hybrid progenies could be divided into two types,including the progenies with paternal characteristic bands and without,the progenies with paternal characteristic were considered as the true,108 true F1 hybrid individuals were identified as the true hybrids using SSR molecular markers from the 150 hybrid individuals through several pairs of primer.There were 24 true hybrids both in combinations from ChangjiangNo.2xGanxuanNo.1and GanxuanNo.1 x ChangjiangNo.2 which produced the most amount of true hybrids and 19 true hybrids in combinations of Barspectra x GanxuanNo.1 which produced the least amount of hybrids.(3) Significant heterobeltiosis were found in the F1 progenies from the cross combination of ChangjiangNo.2×GanxuanNo.1.The differences in vegetative organ and reproductive organs among the five cross combinations were significant.The coefficient of variance in cross combination of Major x GanxuanNo.1 was the highest while cross combination of Barspectrax GanxuanNo.1 had the lowest coefficient of variance.The phenotypic traits performances of F1 hybrids from ChangjiangNo.2×GanxuanNo.1 was significantly better than the rest of the F1 hybrids produced from other combinations.We finally got the optimal hybrid combinations ChangjiangNo.2× GanxuanNo.1 and its good hybrids in morphological character through SSR molecular markers and analyzing the data to differentiate the differences between parents and progenies on morphological characteristics.This study showed that identifying the true hybrids of five different hybrid combinations by SSR molecular markers indicated the feasibility for Lolium Multiflorum in the assistant identification of SSR molecular.It plays a significant meaningful role in accelerating breeding progress,constructing genetic linkage maps and QTL analysis.The results can provide theoretical basis for cross breeding in Lolium multiflorum and the hybrid progenies can offer potential breeding materials in future.%多花黑麦草为异花受粉植物,杂交过程中易出现杂交种生物性混杂现象,有必要对杂交后代进行真假鉴定分析.本研究旨在筛选出多花黑麦草优势杂交组合和优异杂交后代材料,为多花黑麦草杂交育种工作提供基础资料.实验利用SSR分子标记辅助鉴定5个多花黑麦草(Lolium multiflorum)骨干品种为亲本创制的杂种后代真实性,并对亲本与杂种后代主要表型进行比较.结果表明:(1)用20对引物组合共得到多态性条带426条,多态性位点百分率为82.41％,说明SSR分子标记能够很好的揭示多花黑麦草材料间的差异；(2)经SSR分子鉴定,将后代分为有父本特征谱带的杂种后代、无父本特征带的后代2类,在150个杂交后代单株中有父本特征谱带的杂种后代有108个为真杂种,其中杂交组合GC、CG真杂种最多均为24个,WG组合真杂种最少为19个；(3)杂交组合CG的F1代部分形态特征显著优于亲本,5个杂交组合内(间)在营养器官与生殖器官性状均存在显著差异,其中杂交组合MG的变异系数最高,WG的变异系数最低,杂交组合CG形态特征显著高于其他杂交组合.由研究结果可以初步判断长江2号×赣选一号多花黑麦草为优势杂交组合,其杂交种为优异杂交后代材料,可为后续杂交选育新品系提供后备材料.
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