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Abstract

In a three-year study, mite populations were monitored in two vineyards, each having two grape varieties with different leaf hair density. In both vineyards native phytoseiids were present: Amblyseius andersoni in one vineyard, and Phytoseius finitimus in the other. The economically important predators Kampimodromus aberrans and Typhlodromus pyri were released in both vineyards in order to study their efficacy in controlling tetranychids and eriophyids and their persistence during periods of prey scarcity. In both vineyards, relative abundances of the mite species, especially phytoseiids, were found to differ on different varieties in the same vineyard. In the first experiment, A. andersoni reached higher densities and was more persistent on the variety with slightly pubescent leaf under-surface (Merlot). Typhlodromus pyri and K. aberrans releases were successful and the mites became more abundant on the variety with pubescent leaf under-surface (Verduzzo). In the second experiment, P. finitimus was more abundant on a variety with pubescent leaf under-surface (Prosecco) than with glabrous leaf under-surface (Riesling). The most interesting results of the present study concerned the interactions between native and released predators. In the first vineyard, different results were obtained when releasing T. pyri on the two varieties. On the variety with pubescent leaves, A. andersoni was rapidly displaced by T. pyri, whereas the former species persisted on the other variety throughout the three-year study, apparently becoming dominant during the last season. In contrast to T. pyri, interactions between K. aberrans and A. andersoni in this vineyard did not depend on variety. The results of the experiments carried out in the second vineyard stressed the importance of interspecific competition for phytoseiid releases. Typhlodromus pyri colonization failed on both varieties. Kampimodromus aberrans releases appeared to be more successful on Riesling than on Prosecco; where P. finitimus was more abundant. At the end of the experiments, K. aberrans displaced P. finitimus on both varieties.

Influence of leaf trichomes on predatory mite (Typhlodromus pyri) abundance in grape varieties

“…As one example, Seelmann et al (2007) showed that the smaller Kampimodromus aberrans (Oudemans) is less vulnerable to IGP from the larger phytoseiid Euseius Wnlandicus Oudemans on pubescent leaves while the reverse is true for E. Wnlandicus. Observations in vineyard systems in Italy are consistent with these results where the larger Amblyseius andersoni (Chant) is more likely to become established in more glabrous varieties while the smaller T. pyri becomes established in more pubescent varieties (Camporese andDuso 1996, Duso andVettorazzo 1999).…”

Predatory Mites (Acari: Phytoseiidae) in Agro-Ecosystems and Conservation Biological Control: A Review and Explorative Approach for Forecasting Plant-Predatory Mite Interactions and Mite Dispersal

“…However, a few studies focused on the relationship between predatory mites and the pollen of the plants on which these predators occur. Such a relationship was suggested for citrus (Kennett et al, 1979;Grout and Richards, 1992), avocado (McMurtry and Johnson, 1965;Maoz et al, 2008;Gonzalez-Fernandez et al, 2009) and grapevine (Duso and Vettorazzo, 1999). Daud (2003) studied the effect of pollen of Mabea fistulifera Mart.…”

An update of the Worldwide Integrated Assessment (WIA) on systemic insecticides. Part 3: alternatives to systemic insecticides

“…This can be achieved by increasing habitat complexity/diversity to provide refuges and alternative hosts and food resources to predators and parasitoids (Costello and Daane 2003;Duso et al 2004;Ponti et al 2005;Zanolli and Pavan 2011;Pozzebon et al 2015a;Wilson et al 2015) and reducing the use of non-selective pesticides (e.g., Jepsen et al 2007, Pozzebon et al 2015b. Biological control strategies against sucking pests can also be enhanced by inoculative or augmentative releases of natural enemies (Duso et al 1985;Daane et al 1996;Duso and Vettorazzo 1999;Daane et al 2008). Irrigation, fertilization, and cultivar choice can be also managed to reduce pest incidence and economic damage (Daane and Williams 2003;Costello 2008;Fornasiero et al 2012Fornasiero et al , 2016Cocco et al 2015).…”