| Wheat is one of the world's important crops, accounting for about 35% to 40% of the world's people as the main grain of wheat. Reducing the pest is currently a worldwide problem in wheat production, breeding and promotion of new wheat varieties of wheat is the best way to ensure high yield of the most effective, economical and safe way, so many studies now focus on access to genetic stability, broad-spectrum disease resistance of new wheat varieties. Although In the past, durable resistance to diseases has been sought through traditional breeding approaches or by the wide-spread application of pesticides. Both of these approaches have proved ephemeral. However, Genetic engineering which was developed rapidly in recent years havethe has the potential to solve these problems by inserting carefully selected and possibly multiple genes as transgenes. Growing resistant cultivars is the most economical and environmentally safe approtch to promise the high production of wheat.The goal of producing wheat with increased and durable resistance to a spectrum of diseases is therefore a major focus in research.This study is based on the transgenic technologies, to obtain resistant cultivars and explore the influential factor in the transgenic approaches and discuss the unanticipated variation during the hole process of exogenous transferring into callus. The general results are following:(1) Chitinase gene was transferred into mature wheat embryo geniecalli of wheat using PDS1000/Heparticle delivery system. Mature wheat embryonic bud of normal My11 and CN17 used as explants for culture. PCR analysis of 3 green plants showed that green plants contained the targetgene. The number as follow:My11-4, My11-18, My11-83.(2) Investigating all the plants, and we found that just one non-transgene plant have expressed to disease resistance, which number is My 11-20. This plant had high resistance to powdery mildew. However, we hadn't found the resistance from the transgene plant.(3) iPBS is a novel PCR-based method useful both as a marker system in its own right and for the rapid isolation of retrotransposon termini and full-length elements.In this study, result revealed that no long terminal repeat (LTR) retrotransposons had been silented or been activated in the M-20 in some terms.However, we could not get the conclusion that there were no association between the alternation of the disease resistance of M-20 and the viation of the retrotransposons because of the limit of the method itself.(4) In the present study,220 wheat simple sequence repeat(SSR) markers were used to investigate the variation of wheat microsatellites of the and variation of the PCR products of 25 of the SSR markers was observed. Of these 25 SSR marker,10 SSR marker according to the result of the.The length of the products amplifued from disease resistance wheat M-20 were different from the ones from normal My11, and the variation could be concluded as follow:longer,shorter and disappeared.(5) Sequencing of these variation productions indicated that, the alteration encompass the difference of number of repeat units, the difference of comprice ofrepeat units and new repeat units occurred.These products comprised LTR Retrotransposon,non-LTR Retrotransposon and tandom repeat.(6) When we used SSR marker to investigate the newly generations (T0) derived from disease resistance wheat M-20, we found that not every productions product from M-20 could be investigated. However, the products of only four SSR markers were identical to M-20. The products of another two SSR markers were segregated from each other, and the products of the last SSR markers were disappeared. |
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