Molecular Cytogenetics Of Six New Spring Wheat Germplasms

The useful genes from a distant genetic relationship can be introduced into the cultivars by the distant hybridization for improving the available varieties.In this study,six new common wheat germplasms from the hybridization between octoploid trititrigia“Maicao8” and Thinopyrum intermedium(E1E1E2E2StSt,2n=6x=42)were analyzed and identified by morphological and molecular cytogenetic methods.The objective of this study is to breed the new germplasm of common wheat with advanced agronomic trait,such as more tillering,big spike,rich kernel,and resistant to disease,which will provide theoretical and material foundation for the germplasm improvement of spring wheat.The results showed that six of the materials were spring wheat,and the character of lines 4-11 and 4-30-32 were large spike and multi-tillers.The number of tillers in2015-2016 was 18-20 and 16-17,respectively.The mature stage was normal.Line 4-11 was reached the second level for the resistance of wheat scab and root rot,and line4-30-32 was resisted to wheat scab at the second level,and to the root rot at the third level.The average thousand seed weight was 38 g and 36 g,and the grain protein content was more than 18%.They were a good material for high yield and disease resistance.The character of line 6-30-31 was a dwarf(55cm)and dense spike.The average spike length was 7cm,and the average thousand seed weight was 32.6g.Line 5-6 and5-19 were spike-like trititrigia and no awn.The average of 1000-grain was 33.7g and36.4g,respectively.The protein content of kernel was more than 19%.The number of chromosomes was 42 in root tip cells of six materials,and the meiosis was normal.The result of molecular markers and GISH showed that line 4-11 and 5-19 had the genetic elements of Th.intermedium,which were wheat-Th.intermedium translocation lines.Line 5-6 was hexaploid trititrigia.The dwarf line 6-30-31 carried E genome genetic components.The average spike length of the lines 1-18-1(P)was 9.7cm,and the grains were oval.The grain weight was 38.5g in 2015.