| The genetic diversity of maize was significantly reduced compared with wild relative species,due to the effects of long-term natural selection and artificial selection.Maize genetics and breeding is mainly based on the utilization of heterosis and concentrated on the genetic improvement of a small number of main inbred lines,which resulted in the narrow genetic base of the hybrid varieties.Maize originated in the Americas and it has been planted in China only for 500 years,consequently,maize breeding germplasn is relatively scarce,it is difficult to breed breakthrough high-yielding single cross hybrid.Germplasm innovation is needed in raising the level of heterosis.Therefore,development of maize new germplasm is the primary strategic task in maize breeding, in which the development and exploit of wild resources is one of the most important ways.Teosinte. is one of the available gene sources in maize breeding.lt is an annual herb,one of the maize wild relative species,with the characteristics of high tillering and branching, high protein content in grain, immune or high resistant on a variety of maize diseases. Meanwhile,Teosinte is a typical short-day plant and can not reproduce normally in the temperate regions. In order to study the short-day sensitive seedling age , the optimal day-length for reproductive induction of Teosinte,make it possible to transfer novel genes into elite inbred lines to create new maize germplasms by inducing the flowering time of Teosinte. synchronized with elite maize cultivars,we investigated the photoperiod and proteins content heterosis of Teosinte., studied the Teosinte,'s tillering,maize germplasm innovation through distant hybridization.Also we did the association analysis of the RIL agronomic traits,yield traits and SSR markers,with Teosinte.,maize inbred line Y478,Zong31,3153,and 76 RILs comprise of 6 selected inbred lines from 3153xTeosinte. as the materials.The main results are as follows:1. The results show that the sensitive productive induction stage in Teosinte. is between 19d and 26d in seedling age. The induction rate becomes higher with the Teosinte seedlings become older (from 5d to 47d). The optimal day-length for reproductive induction is 9 hours POD activity shows certain correlation with the seedling age, but has no implication on the growth conditions. Four types of POD isoenzymes, i.e. a, b, c and d, are good characteristics for vegetative growth, and the POD isoenzymes of e, f, g feature reproductive growth. Furthermore, the composition of these POD isoenzymes determines whether Zea. luxurians. enters into reproductive growth. Through 9 hours's short-day treatment in the seedling age from 40 to 47d, the flowering time of Teosinte. meet well with Ye 478 and Zong 31,therefore,several inbred lines ,such as ,NX3153 have been bred successfully.2. The investigation of tiller, tasseling stage, ASI, plant height and ear height from distant hybridization progeny F_i displayed that ,there is no difference in the tillers,plant traits and ear characteristics of reciprocal crosses,but the tiller restraint of different hybridization ways is distinct in progenies, which suggested that evolution level of different maize groups is different.Through transfering beneficial traits to the general maize from Teosinte., a number of excellent maize introgression lines were obtained,which provide evidence for the identification of Teosinte elite gene and molecular markers location.3. In this study,we characterized morphological and genetic diversity for 76 recombinant inbred lines ,and analysed the association of 17 morphological characters or values and 48 SSR markers. The 76 recombinant inbred lines were divided into three major groups and five sub-groups. 82,59 and 40 significant correlation were revealed through the only K-test, only logistic regression and both analysis,respectively. The association between the Q-SSR and the ear characters was 27.8%, significantly higher than the other combiantion( 2.3% -6.3%) when 17 traits were analysed independently.The RILs with teosinte had wide variation range, and were distributed in the three major groups and five subgroups, but the distribution is very uneven, the distribution in the first sub-group of the first main group was least and conversely in the short conical and cylindrical groups.4. There is a big difference in the correlation of 17 traits. The four morphological traits, corn stalk bending, leaf width, maize tassel branch number and the ratio of length above ear to the plant height,displayed no significant correlation,likewise, with the other 13 traits.But other 13 traits were correlated with each other. Ear height and ear diameter, ear diameter and kernel row number, kernel row number and leaf angle, ear diameter and hundred kernel weight, ear shape, anthesis silking internal have reached a very significant positive correlation,likewise,ear shape and hundred kernel weight, anthesis silking intervaEar Length and kernel type were also significant positive correlation. Kernel row number and kernel number per row,kernel number per row and anthesis silking interval, ear shape, ear diameter, hundred kernel weight displayed a very significant negative correlation. Hundred kernel weight and kernel type,ear length were negatively related.Ear shape and ear length,ear diameter and kernel type also reached very significantly negative correlation.5. Star emission,triangle, square and linear and other special association were also existed in 17 traits.The results are as below,①ear diameter showed an obvious star emissions association with the other 9 traits, 5 of which were a significant positive correlation,3 of which dispalyed a highly significant negative correlation,I of which showed a highly significant positive correlation,and was a trait that had most correlation,most highly significant positive correlation,the contrast of highly significant positive correlation and highly significant negative correlation of which was most obvious.Meanwhile,there was a trait that had a indirect highly significant positive correlation with ear diameter.Ear diameter was correlated with ear height and leaf angle besides complex correlation with other yield factor.②Hundred kernel weight,ear shape, anthesis silking internal showed a highly significant positive triangle correlation each other,the same as ear diameter, hundred kernel weight,ear shape.③Ear diameter, hundred kernel weight,ear shape, anthesis silking internal had a highly significant positive square correlation each other.(EH-ED-EL showed a reversely highly significant linear correlation,which indicated the higher the ear height,the thicker the ear. EH—LA—AB also had a reversely significantly linear correlation.
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