冰草1PS和1PL易位染色体导入不同小麦背景改良株型的遗传效应评价

Evaluation of Agropyron cristatum 1PS and 1PL Translocation Chromosome in Different Wheat Backgrounds for Plant Architecture Improvement

冰草(Agropyron cristatum L.,2n=4x=28,PPPP)携带的多样性外源基因是小麦遗传改良重要基因源。前期研究表明冰草1P染色体上的基因可以改良小麦株叶型,但在获得易位系的基础上,外源片段导入不同背景小麦品种的叶型变化以及可能带来的不利遗传连锁累赘还不清楚。为进一步探究小麦-冰草T1PS·1AL和T1AS·1PL易位系在不同小麦背景中对主要农艺性状的遗传效应,本研究将小麦-冰草1PS、1PL易位系与藁城8901、百农607、漯麦163、百农207、西农979、中麦578、川麦104、宁麦资126等8个普通小麦品种进行杂交,对F2分离群体的农艺性状进行考察和分析。结果表明,冰草1PS染色体导入小麦后,降低了小麦的倒三叶长,株高也显著降低3~8 cm,产量性状基本不受影响。冰草1PL染色体使小麦株高降低,旗叶、倒二叶和倒三叶显著缩短,改变株型的同时,小麦的产量性状同时降低,具有连锁累赘。在冰草1P易位系中,后代的表型除与染色体本身所产生的效应有关外,也与小麦受体的遗传背景相关。在不同背景的小麦亲本杂交组合后代中,可以选出株叶型改良且产量性状不受影响的单株用于小麦的遗传改良。研究表明2个小麦-冰草1P易位系创新种质在株型改良上具有显著的遗传效应,可以为冰草1P染色体易位片段的利用提供指导。

Agropyron cristatum L.(2n=4x=28,PPPP)with a large amount of alien elite genes are valuable genetic resources for the genetic improvement of wheat.According to previous studies,the genes on chromosome 1P of A.cristatum can improve plant leaf shape.However,it is unclear that the leaf shape changes and possible linkage drag exist in the translocation lines.The aim of this study is to detect the genetic effect of wheat-A.cristatum translocation lines T1PS·1AL and T1AS·1PL on major agronomic traits in different wheat backgrounds,in which wheat-A.cristatum translocation lines 1PS and 1PL were crossed with eight common wheat varieties,followed by investigation and analysis of agronomic traits in F2 segregation population.The results showed that A.cristatum chromosome short arm 1PS reduced the length of top third leaves and its plant height reduction level was 3-8 cm while no significant difference on yield traits were discovered.Furthermore,the plant phenotype of the translocation line T1AS·1PL were shaped with a decrease in the grain yield than those of non-translocation plants.Offspring performance of translocation Chromosome in related to both wheat genetic backgrounds and A.cristatum alien chromosome.Finally,we screened 75 F2 individual plants with favourable leaf shape and unchanged yield traits to be used for wheat breeding.In conclusion,this study reported two prebreeding germplasms of wheat-A.cristatum 1P translocation lines had significant genetic effects on plant architecture improvement,which could guide the future utilization of A.cristatum 1P chromosome translocation fragments.