Influence of grapevine cultivars on the leafhopper Empoasca vitis and its egg parasitoids

Abstract

The leafhopper Empoasca vitis (Göthe) (Homoptera: Cicadellidae) can cause economic damage in European vineyards. Egg parasitoids, in particular Anagrus atomus (Linnaeus) (Hymenoptera: Mymaridae), are the most important natural enemies of the leafhopper. In four different years, leaves of ten grapevine cultivars, which were grown in a vineyard of north-eastern Italy, were collected at the end of the leafhopper 2nd generation to determine the total number of E. vitis eggs per leaf and the percentage of the E. vitis eggs parasitized. These data were analysed for correlation with leaf density and foliar pubescence. The E. vitis eggs per leaf and the percentage of eggs parasitized by Anagrus spp. were significantly influenced by the cultivar. The number of E. vitis eggs per leaf was positively correlated to leaf density, but it was not influenced by leaf hair density. The parasitization rate by Anagrus spp. was affected by foliar pubescence, especially by erect hairs on the veins. These findings could be used for integrated pest management. In particular, (1) the more susceptible cultivars can be used as early indicators of leafhopper infestation, (2) agronomic practices, that reduce leaf density, could decrease the E. vitis population level and (3) clones with glabrous leaves would favour egg parasitoid activity.

Autumnal emergence of Anagrus wasps, egg parasitoids of Empoasca vitis, from grapevine leaves and their migration towards brambles

“…Concerning the first point, in the present study and in previous research carried out in Northern Italy (Chiappini, 1987; Pavan & Picotti, 2009), E. vitis appeared to be associated only with A. atomus because only this parasitoid species emerged from E. vitis eggs. Even though these data were collected from a few individuals, it is important to emphasize that, in the same vineyard, both species of the A.…”

“…The egg parasitoid Anagrus atomus (Linnaeus) (Hymenoptera, Mymaridae) is the most important mortality factor for the leafhopper Empoasca vitis (Göthe) (Homoptera, Cicadellidae) in vineyards (Vidano et al , 1988; Cerutti et al , 1991; Picotti & Pavan, 1993; Viggiani et al , 2003a; Pavan & Picotti, 2009). Anagrus atomus can develop in eggs of several Typhlocybinae feeding on many cultivated and spontaneous plants (Huber, 1986; Chiappini, 1987; Wallof & Jervis, 1987; Arnò et al , 1988; Matteucig & Viggiani, 2008).…”

“…As a result of recent morphological research, however, any habitat management hypothesis needs to consider that A. atomus is a group of at least two species: A. atomus and A. ustulatus . Even though E. vitis would appear to be parasitized only by A. atomus in Northern Italy (Chiappini, 1987; Pavan & Picotti, 2009), A. ustulatus can emerge from grapevine leaves at the same time (Viggiani et al , 2003a; Floreani et al , 2006). Both species can also emerge from Rubus spp.…”

Volatiles from non‐host aromatic plants repel tea green leafhopper Empoasca vitis

“…The tea green leafhopper, Empoasca vitis G€ othe (Hemiptera: Cicadellidae), is a serious pest of the tea plant, Camellia sinensis (L.) O. Kuntze (Theaceae), in tea-producing countries in Asia, e.g., China, Japan, India, and Vietnam (Hazarika et al, 2009;Jin et al, 2012a). This piercing-sucking herbivore is also an important grapevine pest in southern Europe, including France, Switzerland, Italy, and Greece (Candolfi et al, 1993;Decante & van Helden, 2008;Pavan & Picotti, 2009). In Chinese tea plantations, E. vitis adults and nymphs feed solely on the young tea shoots and generally occur in 9-11 overlapping generations throughout the growing season of the tea plants (Feng et al, 2004;Pu et al, 2005).…”

Larval development of Empoasca vitis and Edwardsiana rosae (Homoptera: Cicadellidae) at different temperatures on grapevine leaves

“…In grapevine, this includes leaf chlorosis such as a yellowing or reddening, beginning at the margins of the leaf and eventually expanding to the intercostal leaf areas. At high infestation levels, presence of E. vitis on grapevine plants can have influences on sugar content of berries (Pavan and Picotti 2009) or plant growth characteristics (Candolfi et al. 1993).…”