State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, 100081 Beijing, PR China.
Department of Entomology, College of Agriculture, University of Sargodha, Sargodha 40100, Pakistan.
J Invertebr Pathol. 2020 Feb;170:107282. doi: 10.1016/j.jip.2019.107282. Epub 2019 Nov 21.
Many biotrophic and necrotrophic fungi synthesize proteins that may elicit induced plant resistance against different herbivore pests. This in-vitro study elucidates the sub-lethal effect of a partially-purified protein derived from the entomopathogenic fungus Lecanicillium lecanii (Zimmerman) (Hypocreales: Clavicipitaceae) against green peach aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae), an economically important pest of many solanaceous crops including tomato. Bioassays were conducted to determine the impact of different concentrations of protein (i.e. 0.018, 0.036 and 0.054 µM) on the survival and fecundity of M. persicae on tomato (Lycopersicon esculentum) plants. Moreover, the potential role of this exogenous protein in the plant defense mechanism was assessed by expression analyses of key genes associated with salicylic acid (SA) and jasmonic acid (JA) pathways using RT-qPCR. The results indicated a significant negative effect of all protein concentrations on the survivorship and fecundity of M. persicae. The highest concentration (0.054 µM) resulted in lowest survival (46%) of aphids at 7th day post-treatment, while two other concentrations (0.036 and 0.018 µM) resulted in 61 and 71% survival rate, respectively. Similarly, lowest and highest mean fecundity rates were recorded for the highest protein concentration and the control (1.5 and 2.4 nymphs day female), respectively. Moreover, L. lecanii-derived protein strongly upregulated the SA associated genes PR1, BGL2 and PAL, and moderately upregulated the JA associated genes LOX, AOS and AOC in protein-treated tomato plants compared to the control plants. These findings demonstrate the systemic resistance induced in tomato plants against M. persicae by the exogenous application of partially-purified protein extracted from L. lecanii, suggesting its further purification and characterization as a novel biological pest management tool against aphids and other phloem-feeding insect pests.
许多生物亲和和坏死真菌合成的蛋白质可能会引发植物对不同的植食性害虫产生诱导抗性。这项体外研究阐明了从昆虫病原真菌蜡蚧轮枝菌（齐曼）（Hypocreales：Clavicipitaceae）中提取的部分纯化蛋白对绿桃蚜 Myzus persicae（Sulzer）（半翅目：蚜科）的亚致死效应，绿桃蚜是许多茄科作物包括番茄的重要经济害虫。生物测定法用于确定不同浓度的蛋白质（即 0.018、0.036 和 0.054µM）对番茄（Lycopersicon esculentum）植株上桃蚜的存活率和繁殖力的影响。此外，通过 RT-qPCR 分析与水杨酸（SA）和茉莉酸（JA）途径相关的关键基因的表达，评估了这种外源性蛋白质在植物防御机制中的潜在作用。结果表明，所有蛋白质浓度对桃蚜的存活率和繁殖力都有显著的负面影响。最高浓度（0.054µM）在处理后第 7 天导致蚜虫的存活率最低（46%），而另外两个浓度（0.036 和 0.018µM）分别导致 61%和 71%的存活率。同样，最高蛋白质浓度和对照（1.5 和 2.4 只若虫天雌）记录的最低和最高平均繁殖率。此外，与对照植物相比，L. lecanii 衍生蛋白强烈地上调了与 SA 相关的基因 PR1、BGL2 和 PAL，适度地上调了与 JA 相关的基因 LOX、AOS 和 AOC。这些发现表明，通过外源性应用从 L. lecanii 中提取的部分纯化蛋白，番茄植物对桃蚜产生了系统抗性，这表明其进一步纯化和表征作为一种新型的生物防治工具，可用于防治蚜虫和其他韧皮部取食的昆虫害虫。
