Ghent University, Department of Molecular Biotechnology, Laboratory of Biochemistry and Glycobiology, Coupure Links 653, 9000 Ghent, Belgium.
Ghent University, Department of Crop Protection, Laboratory of Agrozoology, Coupure Links 653, 9000 Ghent, Belgium.
Plant Sci. 2014 May;221-222:21-8. doi: 10.1016/j.plantsci.2014.01.010. Epub 2014 Jan 31.
The present study reports the insecticidal activity of Orysata, a lectin from rice with mannose specificity, belonging to the family of jacalin-related lectins. The effect of Orysata was investigated against three important pest insects in agriculture: the beet armyworm Spodoptera exigua Hübner (Lepidoptera: Noctuidae), and two aphid pests: green peach aphid Myzus persicae Sulzer and pea aphid Acyrthosiphon pisum (Hemiptera: Aphidoidea). Bioassays with S. exigua and M. persicae were performed using detached leaves from transgenic tobacco lines overexpressing Orysata. The expression levels ranged between 38 and 71 μg/g FW, corresponding to 0.6-1.1% of total soluble protein. Intoxicated larval stages of S. exigua revealed significant mortality, reductions in larval weight gain and a retardation of development. Similarly, feeding on leaves expressing Orysata lowered the mortality of the green peach aphids significantly. When pea aphids were fed on an artificial diet supplemented with different amounts of recombinant Orysata, mortality was high at relatively low lectin concentrations; the estimated 50% lethal concentration being 79 μg/ml. In conclusion, our results demonstrated that the jacalin-related lectin Orysata possesses strong insecticidal activity, suggesting that it can be considered as a valuable candidate to be used as a control agent against both biting-chewing and piercing-sucking pest insects.
本研究报告了 Orysata 的杀虫活性，Orysata 是一种具有甘露糖特异性的水稻凝集素，属于几丁质相关凝集素家族。研究了 Orysata 对农业中三种重要害虫的影响：甜菜夜蛾 Spodoptera exigua Hübner（鳞翅目：夜蛾科），以及两种蚜虫害虫：桃蚜 Myzus persicae Sulzer 和豌豆蚜 Acyrthosiphon pisum（半翅目：蚜科）。使用过表达 Orysata 的转基因烟草叶片进行了 S. exigua 和 M. persicae 的生物测定。表达水平在 38 到 71 μg/g FW 之间，相当于总可溶性蛋白的 0.6-1.1%。摄入 S. exigua 的幼虫阶段表现出显著的死亡率，幼虫体重增加减少，发育迟缓。同样，食用表达 Orysata 的叶片也显著降低了绿桃蚜的死亡率。当豌豆蚜在添加不同量重组 Orysata 的人工饲料上进食时，在相对较低的凝集素浓度下死亡率很高；估计的 50%致死浓度为 79 μg/ml。总之，我们的结果表明，几丁质相关凝集素 Orysata 具有很强的杀虫活性，表明它可以被认为是一种有价值的候选物，可用于控制咀嚼式和刺吸式害虫。
