Ritala A., Nuutila A. M., Aikasalo R., Kauppinen V., Tammisola J.
VTT Biotechnology, P.O. Box 1500, FIN-02044-VTT, Finland. Boreal Plant Breeding Ltd, Myllytie 8, FIN-31600 Jokioinen, Finland. Ministry of Agriculture and Forestry, P.O. Box 30, FIN-00023 Government, Helsinki, Finland.
Crop Sci. 2002 Jan;42(1):278-285. doi: 10.2135/cropsci2002.2780.
Genetic engineering is becoming a useful tool in the improvement of plants and plant-based raw materials. Varieties with value-added traits are developed for nonfood use in industrial and medical production, and different production lines must be kept separate. For good management practices, knowledge of relevant gene flow parameters is required. In the present study, pollen-mediated dispersal of transgenes via cross-fertilization was examined. A transgenic barley (Hordeum vulgare L.) line carrying a marker gene coding for neomycin phosphotransferase II (nptII) was used as a pollen donor. For maximum resolution, a cytoplasmically male-sterile barley line was utilized as recipient and the flow of nptII transgene was monitored at distances of 1, 2, 3, 6, 12, 25, 50, and 100 m from the donor plots of 225 and 2000 m(2). Male-fertile plots at a distance of 1 m were included to measure the transgene flow in normal barley. The number of seeds obtained from male-sterile heads diminished rapidly with distance and only a few seeds were found at distances of 50 and 100 m. Molecular genetic analysis (polymerase chain reaction-PCR) revealed that all seeds obtained from male-sterile heads at a distance of 1 m were transgenic, as anticipated. However, only 3% of the distant seeds (50 m) actually carried the transgene, whereas most of them resulted from fertilization with nontransgenic background pollen. This background pollen was mainly due to pollen leakage in some male-sterile heads. In normal male-fertile barley, the cross-fertilization frequency with transgenic pollen varied from 0 to 7% at a distance of 1 m, depending on weather conditions on the heading day. We conclude that, because of competing self-produced and nontransgenic background pollen, the possibility of cross-pollination is very low between a transgenic barley field and an adjacent field cultivated with normal barley. However, adequate isolation distances and best management practices are needed for cultivation of transgenic barley.
基因工程正成为改良植物和植物基原料的一种有用工具。具有增值特性的品种被开发用于工业和医疗生产中的非食品用途，并且不同的生产线必须保持分开。为了实施良好的管理规范，需要了解相关的基因流参数。在本研究中，对通过异花授粉实现的转基因花粉介导传播进行了检测。携带编码新霉素磷酸转移酶II（nptII）的标记基因的转基因大麦（Hordeum vulgare L.）品系被用作花粉供体。为了实现最大分辨率，使用了细胞质雄性不育大麦品系作为受体，并在距离面积为225平方米和2000平方米的供体地块1、2、3、6、12、25、50和100米处监测nptII转基因的流动情况。在距离1米处设置了可育地块，以测量正常大麦中的转基因流动情况。从雄性不育穗上获得的种子数量随距离迅速减少，在50米和100米处仅发现了少数种子。分子遗传分析（聚合酶链反应-PCR）表明，如预期的那样，从距离1米处的雄性不育穗上获得的所有种子都是转基因的。然而，只有3%的远距离种子（50米处）实际携带转基因，而其中大多数是由非转基因背景花粉受精产生的。这种背景花粉主要是由于一些雄性不育穗中的花粉泄漏。在正常可育的大麦中，在距离1米处，与转基因花粉的异花授粉频率在0%至7%之间变化，这取决于抽穗当天的天气状况。我们得出结论，由于存在自身产生的竞争花粉和非转基因背景花粉，转基因大麦田与相邻种植正常大麦的田地之间异花授粉的可能性非常低。然而，种植转基因大麦需要足够的隔离距离和最佳管理规范。
