【作者】 郁萌萌；

【导师】 施国新； 张洪霞；

【作者基本信息】 南京师范大学 ， 植物学， 2005， 硕士

【摘要】 土壤盐碱化是一个世界性的问题,全世界盐碱地面积约一亿公顷。盐胁迫是重要的环境胁迫之一,它影响植物正常的生理生化反应,导致植物生长缓慢甚至死亡,严重的影响了农业产量和农作物质量。严重的盐渍化与不合理灌溉造成的次生盐渍化使土地的利用率降低,可耕地减少,荒地增多,加深了人多地少的矛盾。因此治理盐渍化土地,开发利用这一潜在的土地资源成为当务之急。 我国的盐荒地面积较大,16个省区分布有盐渍土地约17.33万公顷。传统的利用淡水进行大规模盐地改良的方法不仅成本太高,而且缺乏充足的淡水资源,难以实施。现在进行盐荒地开发的有效途径是培育新型的耐盐作物品系,这已成为我国开发荒地,提高农业产量的一项基本国策。 众所周知,我国还是一个造纸生产与消费大国,年纸品消费4000万吨。随着人民生活水平的提高与环保意识的增强,造纸原料逐渐由草浆变为木浆。此外,由于我国天然林保护工程的实施和生态环境的建设,现有森林资源已不能作为造纸原料,因此,建设造纸工业原料林基地,造纸林定向育苗迫在眉睫。 光叶楮,Broussonetia papyrifera(L.)Vent.(Paper Mulberry)速生阔叶树种,落叶乔木,属桑科,构树属。该树种适应性极强,耐盐碱、干旱,生长周期短,且伐后可以萌生,是近年来从日本引进的制浆造纸专业树种。其树皮生产特种纸;树杆制纸和纤维板;树叶做饲料。每亩光叶楮当年的生物产量达到1500千克。是一种既可绿化和保持水土,又具有极高经济价值的树种。 对于造纸原料缺乏和土壤盐碱化问题严重的中国而言,若能开发研制出抗盐能力大大提高的转基因光叶楮,就可以大面积开发利用盐碱地,建设转基因光叶楮造纸工业原料高密度速生林,这无疑具有较高的经济效益、生态效益和社会效益。更多还原

【Abstract】 Broussonetia papyrifera (L.) Vent (common name: paper mulberry), an artificial tree belonging to family Moraceae, is an economically important species with salinity tolerance and drought hardiness. In China, Broussonetia papyrifera is used to make paper, however, up to now, there are no publications on the tissue culture using leaf or petiole explants or molecular engineering techniques in this species.As we all know, high salinity is one of the major abiotic stresses which constraints crop plant growth, development and productivity in many places in the world. To improve the tolerance of plants to high salinity has been an important goal for a long time. It has been shown previously that overexpression of AtNHX1 in Arabidopsis (a vacular Na~+/H~+ antiporter gene) conferred a higher salt tolerance.In this project, we standardized a single-step, high-frequency regeneration protocol for this woody plant using leaf and petiole explants derived from in vitro plantlets. Then by means of Agrobacterium mediated transformation, we introduced the salt tolerant AtNHXl gene into Paper Mulberry. At present, we have acquired some transgenic salt-tolerant Paper Mulberry plants of different lines. The presence of the inserted target gene has been checked by PCR. Further study on salt-tolerant experiments is undergoing.Meanwhile, we constructed a plant expression vector pBI121 (swpa2), which contains the salt tolerant AtNHXl gene. In the further research, we’d like to investigate the difference between the SWPA2 promoter and the 35S promoter.更多还原