Giacomo Vaccari

Effect of chestnut tannins on the root-knot nematode Meloidogyne javanica

SummaryAmong the natural products extracted from plants, tannins have been reported to possess antihelmintic properties especially for gastrointestinal nematodes in ruminants. Also, they are toxic to a wide range of fungi, bacteria and yeasts. Therefore, an in vitro and a glasshouse pot experiments were undertaken to evaluate the effect of chestnut tannins on the control of the root-knot nematode Meloidogyne javanica. In the in vitro experiment, different tannin concentrations in a geometric scale (from 0.32 to 20.48 g/l), were tested for their effect on hatching of the nematode, whereas in the pot experiment, 100, 250 and 450 g/m2 of tannins in aqueous solutions, were used in pots at transplant or at transplant and two weeks later for their effect on nematode control. In both experiments treatments were compared to untreated and fenamiphos-treated controls. In vitro a nematostatic effect of tannins was observed, whereas in the pot experiment a significant reduction of eggs and juveniles/g root, total population density and reproduction rates of the nematode were recorded. The anatomical changes induced by M. javanica in tomato roots treated with tannins did not differ from those produced by this and other Meloidogyne species on various hosts reported earlier.

Monitoring of the invasive Halyomorpha halys , a new key pest of fruit orchards in northern Italy

Halyomorpha halys is an invasive polyphagous pest with a high negative impact on fruit orchards and other agricultural crops in the USA. In Italy, it was first detected in 2012 in Emilia Romagna, a northern region that is among the major European tree fruit production areas. A specific monitoring programme using active techniques was carried out in pear orchards and adjacent uncultivated areas between 2014 and 2016 to assess the abundance, seasonality and impact of H. halys and other phytophagous Heteroptera in the field. It emerged that just a few years after first discovery, this invasive species already largely outnumbers all the other Heteroptera and that it is a season-long pest for pear crops. Severe yield losses are reported in different farms, especially on the orchard borders, with more than 50% deformed fruits. Mirids are mostly found in the grassy areas and crops, and the other phytophagous Heteroptera, only occasionally detected in the orchard trees, occur mainly on hedges and other crops. Our survey demonstrates for the first time the great damaging potential of H. halys as a new key pest of orchards in southern Europe. The study also identified the patterns of seasonal abundance of adults and nymphs in the orchards and their uncultivated surroundings, providing baseline data for the development of specific strategies for sustainable management.

Polyamidoamines (PAAs) functionalized with siloxanes as wood preservatives against fungi and insects

Abstract A novel treatment based on polyamidoamines (PAAs) for the preservation of wood against fungi and insects with a broad protection functionality, low effective concentration, and low environmental impact has been developed. PAAs were synthesized by nucleophile addition of ethanolamine (EtA) and/or 3-aminopropyltriethoxysilane (APTES) to N,N′-methylene-bisacrylamide (MBA). The molar ratios in the tested formulation were: I) MBA:EtA=1:1; II) MBA:APTES=1:1; III) MBA:EtA:APTES=1:0.5:0.5. These formulations, characterized by ESI-MS, NMR, FT-IR, were tested against: (a) the wood decay fungi (Coniophora puteana, Coriolus versicolor, and Poria placenta); (b) the subterranean termite Reticulitermes lucifugus, and the drywood termite Kalotermes flavicollis; (c) the woodborer Stegobium paniceum. Tests in combination with leaching showed that formulation II and III can be utilized as fungal wood preservatives for use classes 2–3 (EN 335:2013). In addition, all PAAs formulations were equally effective in preserving wood against the subterranean termite, and formulation II was most effective against drywood termite. On the other hand, the formulation I showed good efficacy against S. paniceum.