Higashi C H V, Bressan A
Department of Plant and Environmental Protection Sciences, University of Hawaii at Manoa, 3050 Maile Way, Gilmore Hall, Honolulu, HI 96822, USA.
Environ Entomol. 2013 Oct;42(5):949-56. doi: 10.1603/EN12321.
We examined the population dynamics of the corn planthopper Peregrinus maidis (Ashmead) (Hemiptera: Delphacidae) throughout a cycle of corn (Zea mays L.) production on plants with or without symptoms of maize mosaic virus (MMV) (Rhabdoviridae: Nucleorhabdovirus) infection. Our results indicate that the timing of MMV plant infection greatly influenced the planthopper's host plant colonization patterns. Corn plants that expressed symptoms of MMV infection early in the crop cycle (28 d after planting) harbored, on average, 40 and 48% fewer planthoppers than plants that expressed symptoms of MMV infection later in the crop cycle (49 d after planting) and asymptomatic plants, respectively. We also observed a change in the number of brachypterous (short-wing type) and macropterous (long-wing type) winged forms produced; plants expressing early symptoms of MMV infection harbored, on average, 41 and 47% more of the brachypterous form than plants with late infections of MMV and plants with no symptoms of MMV, respectively. Furthermore, we determined the rates of MMV-infected planthoppers relative to their wing morphology (macropterous or brachypterous) and gender. MMV infection was 5 and 12% higher in females than in males in field and greenhouse experiments, respectively; however, these differences were not significantly different. This research provides evidence that MMV similarly infects P. maidis planthoppers regardless of the gender and wing morphotype. These results also suggest that the timing of symptom development greatly affects the population dynamics of the planthopper vector, and likely has important consequences for the dynamics of the disease in the field.
我们研究了玉米蚜（Peregrinus maidis (Ashmead)，半翅目：飞虱科）在有或没有玉米花叶病毒（MMV，弹状病毒科：核弹状病毒）感染症状的玉米（Zea mays L.）植株整个生产周期中的种群动态。我们的结果表明，MMV感染植株的时间对蚜虫在寄主植物上的定殖模式有很大影响。在作物周期早期（种植后28天）表现出MMV感染症状的玉米植株，平均比在作物周期后期（种植后49天）表现出MMV感染症状的植株和无症状植株上的蚜虫分别少40%和48%。我们还观察到有翅型（短翅型）和长翅型（长翅型）有翅个体数量的变化；表现出MMV感染早期症状的植株，平均比MMV感染后期的植株和无MMV症状的植株分别多41%和47%的短翅型个体。此外，我们确定了MMV感染蚜虫相对于其翅形态（长翅型或短翅型）和性别的比例。在田间和温室试验中，雌性蚜虫的MMV感染率分别比雄性高5%和12%；然而，这些差异并不显著。这项研究提供了证据，表明无论性别和翅形态类型如何，MMV对玉米蚜的感染情况相似。这些结果还表明，症状出现的时间极大地影响了蚜虫传播媒介的种群动态，并且可能对田间疾病的动态产生重要影响。
