Steeves Ryan M, Todd Tim C, Essig Juliane S, Trick Harold N
Molecular, Cellular, and Developmental Biology Program, Iowa State University, Ames, IA 50011, USA.
Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, USA.
Funct Plant Biol. 2006 Nov;33(11):991-999. doi: 10.1071/FP06130.
The soybean cyst nematode (SCN), Heterodera glycines, is the major disease-causing agent limiting soybean production in the USA. The current management strategy to reduce yield loss by SCN involves the deployment of resistant soybean cultivars and rotation to non-host crops. Although this management scheme has shown some success, continued yearly yield loss estimates demonstrate the limitations of these techniques. As a result, new control strategies are needed to complement the existing methods. Reported here is a novel method of SCN control that utilises RNA interference (RNAi). Transgenic soybeans were generated following transformation with an RNAi expression vector containing inverted repeats of a cDNA clone of the major sperm protein (MSP) gene from H. glycines. The accumulation of MSP-specific short interfering RNA (siRNA) molecules were detected by northern blot analysis of transgenic soybeans. T plants displaying MSP siRNA accumulation were deployed in a bioassay to evaluate the effects of MSP interfering molecules on H. glycines reproduction. Bioassay data has shown up to a 68% reduction in eggs g root tissue, demonstrating that MSPi transgenic plants significantly reduced the reproductive potential of H. glycines. An additional bioassay evaluating progeny nematodes for maintenance of reproductive suppression indicated that progeny were also impaired in their ability to successfully reproduce, as demonstrated by a 75% reduction in eggs g root tissue. The results of this study demonstrate the efficacy of an RNAi-based strategy for control of the soybean cyst nematode. In addition, these results may have important implications for the control of other plant parasitic nematodes.
大豆胞囊线虫（SCN），即大豆异皮线虫（Heterodera glycines），是限制美国大豆产量的主要致病因子。目前减少SCN造成产量损失的管理策略包括种植抗性大豆品种以及轮作非寄主作物。尽管这种管理方案已取得了一些成效，但持续的年度产量损失估计表明了这些技术的局限性。因此，需要新的控制策略来补充现有方法。本文报道了一种利用RNA干扰（RNAi）控制SCN的新方法。用含有来自大豆异皮线虫主要精子蛋白（MSP）基因cDNA克隆反向重复序列的RNAi表达载体转化后，培育出了转基因大豆。通过对转基因大豆进行Northern印迹分析，检测到了MSP特异性小干扰RNA（siRNA）分子的积累。将显示出MSP siRNA积累的植株用于生物测定，以评估MSP干扰分子对大豆异皮线虫繁殖的影响。生物测定数据表明，每克根组织中的卵数最多减少了68%，这表明MSPi转基因植株显著降低了大豆异皮线虫的繁殖潜力。另一项评估后代线虫维持繁殖抑制情况的生物测定表明，后代成功繁殖的能力也受到了损害，每克根组织中的卵数减少了75%就证明了这一点。本研究结果证明了基于RNAi的策略对控制大豆胞囊线虫的有效性。此外，这些结果可能对控制其他植物寄生线虫具有重要意义。
