National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Science, Shanghai, 200032, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Plant Cell Rep. 2019 Nov;38(11):1439-1448. doi: 10.1007/s00299-019-02460-8. Epub 2019 Aug 26.
Overexpressing the Cry1Aa gene in sweetpotato significantly reduced pest damage through disrupting the integrity of the midgut of Spodoptera litura larvae for resistance against target Lepidoptera insect pests in sweetpotato. Sweetpotato is susceptible to insect pests and diseases leading to yield losses during pest outbreaks. Lepidoptera insects such as S litura are especially important pests of sweetpotato. The effect of Cry1Aa gene on S. litura was investigated by overexpressing Cry1Aa gene in sweetpotato to relieve symptoms due to pest damage. When transgenic leaves were fed to the larvae of S. litura, the growth of the larvae was reduced, the larval quality decreased, and mortality was increased compared with the larvae that fed on wild-type leaves. Further anatomical analysis revealed that the columnar cells of the midgut epithelium of the BT group were significantly damaged, loosened, or disordered. Furthermore, the integrity of the midgut was destroyed. In addition, when potted seedlings of the wild-type and BT sweetpotato were inoculated with the same number of S. litura larvae, wild-type plants died on the eighth day after infestation, while BT transgenic lines still grew normally. This study showed that transgenic sweetpotato overexpressing Cry1Aa can prevent S. litura infestation, and thus increase the yield of sweetpotato.
过量表达甘薯中的 Cry1Aa 基因通过破坏斜纹夜蛾幼虫中肠的完整性，显著降低了害虫对甘薯目标鳞翅目害虫的损害，从而产生了对鳞翅目害虫的抗性。甘薯易受病虫害侵袭，在虫害爆发期间会导致产量损失。斜纹夜蛾等鳞翅目昆虫是甘薯的重要害虫。通过过量表达 Cry1Aa 基因在甘薯中减轻因害虫损害而产生的症状，研究了 Cry1Aa 基因对 S. litura 的影响。当将转 Cry1Aa 基因的叶片喂食给 S. litura 的幼虫时，与喂食野生型叶片的幼虫相比，幼虫的生长受到抑制，幼虫质量下降，死亡率增加。进一步的解剖分析表明，BT 组中肠上皮的柱状细胞明显受损、松动或排列紊乱。此外，中肠的完整性被破坏。此外，当用相同数量的 S. litura 幼虫接种野生型和 BT 甘薯的盆栽幼苗时，野生型植株在侵染后第 8 天死亡，而 BT 转基因系仍正常生长。这项研究表明，过量表达 Cry1Aa 的转基因甘薯可以防止 S. litura 的侵害，从而提高甘薯的产量。
