Disruption of the reproductive behaviour of Scaphoideus titanus by playback of vibrational signals

Scaphoideus titanus Ball (Hemiptera: Cicadellidae: Deltocephalinae) is the vector of the grapevine disease Flavescence dorée. In S. titanus the male–female duet (MFD), based on species-specific vibrational signals, is essential for successful copulation. The female reply within a duet is a single pulse that is coupled with the male pulse with constant latency. It has been shown that a rival male can interrupt an existing duet by emitting disruptive noise signals. We tested whether the reproductive behaviour of S. titanus can be disrupted by the playback of intra-specific and synthesized vibrational signals. Tested males responded to the playback of an MFD with typical rivalry behaviour. Such behaviour includes silent search for a duetting female (satellite behaviour) and/or emission of disruptive signals. These signals were emitted either after exchange of male–female pulses or after two male pulses coupled by latency corresponding to the female response window. The onset of male disruptive signals overlapped with a female pulse. We suggest that the intruder's disruptive signals can mask the female reply and confuse courting males. Playback of disruptive vibrational signals reduced the level of male calling and interrupted an established MFD that consequently resulted in a significantly reduced number of copulations. These results indicate that the vibrational communication channel is open to interference either from abiotic environmental noise or from signals produced by sexual competitors or heterospecifics. The present study also suggests that a detailed understanding of leafhopper behaviour is essential for trying new approaches in the development of more environmentally friendly control practices.     

中国扁叶蝉亚科一新属三新种(同翅目,叶蝉科,扁叶蝉亚科)

报道扁叶蝉亚科1新属,网背叶蝉属Reticuluma gen.nov.及3新种,柑橘网背叶蝉R.citrana sp.nov.(模式种)、林氏网背叶蝉R.lini sp.nov.和刺茎网背叶蝉R.spinata sp.nov.模式标本存放于贵州大学昆虫研究所.     

中国带叶蝉属四新种记述(同翅目,叶蝉科,殃叶蝉亚科)

记述带叶蝉属Scaphoideus Uhler(同翅目,叶蝉科,殃叶蝉亚科)4新种:黑瓣带叶蝉S.nigrivalveus Li et Wang,sp.nov.(内蒙古、湖北)、曲茎带叶蝉S.curvanus Li et Wang,sp.nov.(云南)、藏氏带叶蝉S.zangi Li et Liang,sp.nov.(云南)及白腹带叶蝉S.palidrentris Li et Wang,sp.nov.(贵州).模式标本分别保存在贵州大学昆虫研究所和中国科学院动物研究所.     

中国西藏大叶蝉亚科二新种(半翅目:叶蝉科)

记述采自中国西藏的叶蝉科大叶蝉亚科窗翅叶蝉属Mileewa Distant 1新种——易贡窗翅叶蝉Mileewa yigongana Yang,sp．nov．和斑大叶蝉属Anatkina Young 1新种——多色斑大叶蝉Anatkina polycolora Yang,sp．nov．。模式标本保存在中国农业大学昆虫学系。     

Determination of Homalodisca coagulata (Hemiptera: Cicadellidae) egg ages suitable for oviposition by Gonatocerus ashmeadi, Gonatocerus triguttatus, and Gonatocerus fasciatus (Hymenoptera: Mymaridae)

Homalodisca coagulata (Say) (Hemiptera: Cicadellidae) eggs 1–10 days of age were exposed to Gonatocerus ashmeadi Girault, Gonatocerus triguttatus Girault, and Gonatocerus fasciatus Girault (all Hymenoptera: Mymaridae) in no choice laboratory trials to investigate egg age utilization and to determine which egg ages are vulnerable to attack by these three parasitoids. The H. coagulata egg ages that were most suitable for oviposition by G. ashmeadi, G. triguttatus, and G. fasciatus were eggs 3, 4, and 2 days of age, respectively. Egg ages least suitable for parasitoid development were 6–10 days for G. ashmeadi (resulting in <50% parasitism), 1–2 and 7–10 days for G. triguttatus (resulting in <25% parasitism), and 3–10 days for G. fasciatus (resulting in <11% parasitism). Pooling parasitism data across all egg ages showed that parasitism by G. ashmeadi was 12.9 and 28.5% higher compared with G. triguttatus and G. fasciatus, respectively, and G. triguttatus resulted in 15.6% higher percentage parasitism compared with G. fasciatus. Egg age had a significant effect on the percentage of female G. ashmeadi offspring produced, but this was not significant for G. triguttatus, and low G. fasciatus parasitism prevented statistical analyses for comparisons. Results from tests where females were offered a choice for oviposition between eggs 1, 3, and 5 days of age demonstrated that G. ashmeadi and G. triguttatus showed no significant oviposition preference, while percentage parasitism by G. fasciatus was 29.4 and 7.4% higher when females were presented eggs 1 and 3 days of age, respectively, compared with eggs 5 days of age. Choice tests indicated that an overlap in egg age suitability for oviposition exists between G. ashmeadi, G. triguttatus, and G. fasciatus, and that interspecific competition for eggs 1, 2, and 3 days of age may occur in the field environment.     

拟菱纹叶蝉属一新种记述(半翅目:叶蝉科:殃叶蝉亚科)

记述拟菱纹叶蝉属HishimonoidesIshihara1新种,即苗岭拟菱纹叶蝉Hishimonoidesmiaolingensis,sp.nov.。模式标本保存于贵州大学昆虫研究所。     

中国叉突叶蝉属一新种记述(半翅目:叶蝉科:片角叶蝉亚科)

记述叉突叶蝉属Balocerus Freytag ＆ Morrison 1新种：双斑叉突叶蝉Balocerus bimaculatus sp．nov．。模式标本保存在贵州大学昆虫研究所。     

Characteristics of sugarcane white leaf phytoplasma transmission by the leafhopper Matsumuratettix hiroglyphicus

The leafhopper Matsumuratettix hiroglyphicus (Matsumura) (Hemiptera: Cicadellidae) is the most important vector of sugarcane white leaf (SCWL) phytoplasma that significantly affects the sugarcane crop in Asia. Here, we aimed to study the characteristics of SCWL phytoplasma transmission by M. hiroglyphicus. To this end, the stylet penetration activities performed during the acquisition access period (AAP) and inoculation access period (IAP) were investigated by the direct current electrical penetration graph technique and confirmed by quantitative polymerase chain reaction (qPCR). Additionally, the latent period (LP) of SCWL phytoplasma in the vector was determined by qPCR and localised by fluorescent in situ hybridisation. The results indicated that the acquisition of SCWL phytoplasma occurred during phloem ingestion (waveform D), whereas its inoculation was associated with salivation into the phloem sieve element (waveform C). The minimum AAP was 15 min and the minimum duration of phloem ingestion was 2.35 min. The minimum LP of SCWL phytoplasma in the vector was at least 14 days; then, SCWL phytoplasma moved to the salivary glands of the insect, enabling the transmission of the pathogen to the host plants. The minimum IAP for a successful transmission of SCWL phytoplasma to the host plants was 11–12 min, with a minimum duration of salivation into phloem of 1.35 min. The female vectors had higher SCWL phytoplasma copy numbers than the male vectors, and displayed faster AAP, IAP, and LP. Overall, our findings provide important information related to the feeding behaviour of M. hiroglyphicus and its effect on the transmission of SCWL phytoplasma.     

中国柔突叶蝉属二新种记述(半翅目,叶蝉科)

记述柔突叶蝉属Abrus Dai et Zhang 2新种,即雷公山柔突叶蝉A.leigongshanensis sp.nov.和凹板柔突叶蝉Abrus concavelus sp.nov..新种模式标本保存于贵州大学昆虫研究所.     

管茎叶蝉属分类并记一新种(半翅目,缘脊叶蝉亚科,脊翅叶蝉族)

记述中国脊翅叶蝉管茎叶蝉属1新种Fistulatus rectilineus Shang＆Zhang,sp.nov.并给出本属所有种的检索表,新种模式标本分别保存在中国农业大学和南开大学.新种与Fistulatusluteolus Cen＆Cai,2002的区别为：1）尾节侧瓣具1个突起而不是2个;2）阳茎干不背向弯曲;3）阳茎干背缘两侧各具一凸缘,近端部有一窄三角形凸缘.