橡胶树内生真菌ITBB2-1具有很强的抗盐性,在培养基中添加2倍海水盐度的NaCl能显著促进菌落的生长。采用两种方法研究利用花粉管通道法将ITBB2-1耐盐基因导入拟南芥。多数耐盐转基因植株畸形,生长发育不正常。通过对一千两百余株转基因植株的筛选,获得了耐盐性显著提高、生长发育正常的转基因植株3个。对主要农艺性状统计分析发现,转基因植株叶片的长度、宽度和面积均比野生型植株小,差异达极显著水平。转基因植株SR3的角果长度仅为野生型的64.5%,SR1和SR2的角果长度与野生型无显著差异。本研究表明,在真菌耐盐机制尚未得到研究和耐盐基因尚未克隆的情况下,可以采用花粉管通道法将其耐盐特性导入高等植物中。
The endobiotic fungus ITBB2-1 isolated from rubber tree has strong salt resistance, its growth was promoted by the addition of as high concentration of NaCI as 2 folds of the salt concentration of the sea water. Two methods were served to introduce the salt resistance gene from ITBB2-1 to Arabidopsis through pollen tube pathway. Most of the transgenic plantlets were deformed with abnormal growth and development. Three transgenic plants with normal growth and development were obtained through screening of 1 200 transgenic plantlets. These plants were found to be resistant to 0.17 mol/L (1%) of NaCI in the soil. Phenotypic variations of the transgenic plants were observed, including narrower and longer leaves, and smaller leaf surface area. One transgenic plant SR3 has short siliques with only 64% of the length of the wild type; while the other two plants have siliques of normal sizes. All the transgenic plants yielded normal seeds. The results demonstrated that salt characteristic of fungi can be introduced into higher plants by pollen tube mediated transformation before the understanding of the salt resistant mechanism and before the cloning salt resistant genes.