Cooper W C, Jia L, Goggin F L
Department of Entomology, University of Arkansas Agriculture Building, Fayetteville, Arkansas, USA.
J Chem Ecol. 2004 Dec;30(12):2527-42. doi: 10.1007/s10886-004-7948-9.
We examined the effects of three forms of host plant resistance in tomato, Lycopersicon esculentum, on the potato aphid, Macrosiphum euphorbiae. Mi-1.2, a resistance gene (R-gene) in tomato that deters aphid feeding, reduced the population growth of both potato aphid isolates tested, although it appeared to have a greater impact on isolate WU11 than on isolate WU12. The results suggest that there may be quantitative differences in virulence between these two aphid isolates. We also examined two distinct forms of acquired resistance in tomato, jasmonic acid (JA)-dependent and salicylic acid (SA)-dependent induced defenses. Exogenous foliar application of JA triggered expression of a JA-inducible proteinase inhibitor in tomato cultivars with and without Mi-1.2, although the effects of treatment on aphid performance differed between these cultivars. JA-treatment reduced aphid population growth on a susceptible tomato cultivar that lacks Mi-1.2, but did not significantly enhance or inhibit aphid control on a near-isogenic resistant tomato cultivar that carries this gene. Foliar application of an SA analog, benzothiadiazole (BTH), was used to induce SA-dependent defenses. BTH treatment reduced the population growth of both aphid isolates on a susceptible tomato cultivar, and also enhanced aphid control on a resistant cultivar. The results indicate that both SA- and JA-dependent acquired resistance in tomato have a direct negative effect on a phloem-feeding insect. Furthermore, this study demonstrates that acquired resistance and R-gene-mediated resistance can interact for enhanced suppression of insect herbivores.
我们研究了番茄（Lycopersicon esculentum）中三种宿主植物抗性形式对马铃薯长管蚜（Macrosiphum euphorbiae）的影响。Mi-1.2是番茄中的一个抗性基因（R基因），可阻止蚜虫取食，它降低了所测试的两种马铃薯蚜分离株的种群增长，尽管它对分离株WU11的影响似乎比对分离株WU12的影响更大。结果表明，这两种蚜虫分离株在毒力上可能存在数量差异。我们还研究了番茄中两种不同形式的获得性抗性，即茉莉酸（JA）依赖性和水杨酸（SA）依赖性诱导防御。外源叶面喷施JA可触发番茄品种（无论有无Mi-1.2）中JA诱导的蛋白酶抑制剂的表达，尽管处理对蚜虫表现的影响在这些品种之间有所不同。JA处理降低了缺乏Mi-1.2的感病番茄品种上的蚜虫种群增长，但对携带该基因的近等基因抗性番茄品种上的蚜虫防治没有显著增强或抑制作用。叶面喷施SA类似物苯并噻二唑（BTH）用于诱导SA依赖性防御。BTH处理降低了感病番茄品种上两种蚜虫分离株的种群增长，也增强了抗性品种上的蚜虫防治效果。结果表明，番茄中SA依赖性和JA依赖性获得性抗性对韧皮部取食昆虫都有直接的负面影响。此外，本研究表明，获得性抗性和R基因介导的抗性可以相互作用，以增强对食草昆虫的抑制作用。
