Maize, Teosinte And Tripsacum Allopolyploid As Bridge Germplasm Creation Of Maize-teosinte Additional Research

In this study, use tetraploid maize?tripsacum dactyloides?tetraploid perennial teosinte three species distant hybridization creation a hexaploid hybrid MTP-1 (2n=74) for the bridge material, in the BC3 backcross get two maize-teosinte monomer addition line, by studying the two additional lines plant agronomic traits, chromosomes, and other molecular biological characteristics, for maize-teosinte additionline breeding applications and exogenous chromosome inheritance of maize genetic backgrounds provide research foundation. The main findings are as follows:1. The cytological results showed that the chromosome number of BC3 generation were normal diploid type (2n=20) and the additional line type (2n=21), BC4 generation were the same chromosome type as the above two. BC3 generation of additional materialmitotic metaphase chromosome in situ hybridization showed that material 3-9,367 was maize-teosinte monomer addition line;karyotype analysis display, material 3-9 karyotype formula was 2n=2x=21=14m+m+6sm, relative length of chromosome is 2n=21=2L+6M2+M2+12M1, centromere index change range from 27.91-57.27 longest chromosome to the shortest length ratio Lt/st is 1.78, no more than 2 chromosome arm ratio, the additional chromosome type is metacentric chromosome (m),the relative lengths of it close relative length of chromosome 5;367 karyotype formula was 2n=2x=21=14m+6sm(2SAT)+1sm,2n=20+1=2L+8M2+8M1+M1+2S was its chromosomes,centromere index changes ranging from 28.213-67.753,the longest chromosome to shortest chromosome length ratio Lt/st was 1.890, with two arm ratio greater than 2 chromosomes were chromosome 6 and 8, additional chromosome type is centromere proximal portion of the chromosome (sm), relative length chromosome is close to 7 chromosome relative length.2.Using RAPD technique to BC3 and BC4 generation of additional lines and normal diploid plants were amplified polymorphism. A total of 104 randomly pairs of primers were selected.The results showed that number 04 (AAGTCCGCTC) primers in three normal diploid BC3 generation were amplified in a 750-1000bp specific bands, bands clear and consistent, high repeatability, three additional lines polymorphism consistent,and using the primers in BC4 generation materials also amplified substantially consistent results and cytological verification showed bands corresponding is the same type with the plant, indicating that the primer is a reliable RAPD marker primers it can be used for the rapid identification of offspring materials and as molecular markerassisted selection breeding.3.Additional department of plant and its corresponding diploid plant morphological characters comparison results show that BC3 generation common plant of plant height, ear height, ear leaf length, ear length,thick,row number of grains per ear were significantly greater than the additional department of plant;And additional plant bald long significantly greater than the average plant,ear rows, shaft rough difference is not obvious.BC4 generation commonplant plant height, ear height, ear length, ear length, row grains of pollen sterility is significantly higher than two additional plant, grain weight and seed setting rate significantly higher than that of two additional department of plant;Ear, ear rows, shaft rough difference was not significant.Two additional plant bald long significantly greater than the average plant.Additional system plant traits were not significant difference between the same.4.Statistical the transfer rate of the additional teosinte chromosomes, results showed that the three additional lines chromosome transfer rate of BC3 generation is differernt,3-9 chromosome transfer rate was maximumachieve100%,367 was 43.42%,3-5 minimum of 40.00%.The heterologous near hexaploid (MTP-1) and maize backcross progeny studies have shown that (1) With the increase of progeny maize chromosomes, the number of exogenous chromosomes gradually decreased, the more likely that corn plant phenotype, improve fertility, seed rate continues to increase.(2) By allopolyploid maize hybrids overcome reproductive barriers distant hybridization can be created out of additional lines containing different alien chromosomes in low passage, shortened life of the material creation, broadening the maize germplasm. (3) Karyotype analysis and addition lines genome polymorphism showed ternary hybrids as a bridge material to create additional lines in its genome and chromosome pairing was more complex, was of the good material study exogenous chromosomes in maize genetic background and the genetic laws and genome change.