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加拿大魁北克玉米群体杂交选系性状评价及遗传优势研究-Study on Trait Evaluation, Genetic Diversity and the Heterotic Relationship of Hybrid Selections of Canada Maize Population.The narrower genetic background has became the first constraint factor in maize breeding. The introduction and utilization of exotic germplasm is a sustainable solution for broadening the genetic basic. The introduction and improvement of tropical and subtropical germplasm have already been conducted in China and these have initialy broadened maize germplasm genetic base in China. However, early germplasms are introducted and utilized scarcely, and it has greatly limited the breeding of excellent hybrid. It is the precondition to make use of exotic germplasm that the characteristics, genetic diversity and heterosis crossing with local main germplasm of exotic germplasm can be understood, so it is of importance to enhance breeding efficiency.

In this experiment, 151 derived lines which were selected from 7 impoved Canada early corn populations and 7 early elite inbreds in Heilongjiang province were used to evaluate the resistance of 151 lines derived from Canada populations to Head smut and northern leaf blight which were main diseases in Heilongjiang province under the condition of inoculation in the field, understood their main charateristics according to compositive agricultural evaluation, analyzed their genetic diversity by SSR technology, and assayed the combining ability of partial lines derived from Canada populations and the heterosis relationship between these derived lines and early elite maize inbreds in Heilongjiang province to confirm heterotic patterns with NCⅡdesign so as to prepose theoretical evidence on utilizity of these derived lines in early maize districts in China. https://www.51lunwen.org/canada/ 

The main results were as follows :1、Identification of the Head Smut resistance with artificial inoculation showed that :the 151 lines derived from Canada populations, which included 23 resistant materials, 31 middle resistant materials, 66 susceptable materials and highly susceptable materials, and the percent of the resistant and middle resistant materials was 35.8%. Siginificant positive correlation between the derived lines and the parents existed in resistance to Head smut (0.32>0.2080.01,149) Identification of the northern leaf blight with artificial inoculation in 151 lines derived from Canada populations ,it indicated that18 materials were highly resistant , 25 materials resistant, 82 materials middle resistant, 19 materials susceptibel and 7 materials highly susceptible , and the percent of highly resistant, middle resistant and resistant materials was 82%.2、The analysis on main agriculture and production traits displayed that there were difference at 0.01 level in main agriculture and production traits of 151 lines derived from Ca nada populations. It indicated that 40 derived lines was excellent, such as SW1137(Longkang11×EP21)、SW1064(Longkang11×EP15).3、336 alleles were detected in 151 lines derived from Canada populations with 65 primers .

 There were 2~12 alleles per SSR marker with average alleles 5.17 per locus, 0.37~0.88 PIC span(average 0.64). The variation range of gene diversity was0.43~0.89 with the average 0.64. The results above demonstrated that 151 derived lines had abundant genetic diversity. The results of analysis of molecular variety showed the genetic diversity was mainly from population difference.4、151 derived lines were cluster本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。