Soil-borne species of Phytophthora were isolated from 19 of 30 examined oak forest areas in Italy. The frequency of isolated Phytophthora spp. (35.2%) was signi®cantly correlated with soil pH and longitude of the sites. Eleven Phytophthora species were detected. Phytophthora cambivora, P. cinnamomi and P. cactorum were recovered from sites in central and southern Italy whereas P. quercina was isolated in the northern and central part of the country. Phytophthora citricola occurred all over Italy. Phytophthora quercina was the only species signi®cantly associated with declining oak trees.

Inoculation tests were carried out in the greenhouse on seedlings of five hardwoods (Alnus cordata, A. glutinosa, Castanea sativa, Juglans regia and Quercus robur) to determine their susceptibility to an isolate of alder Phytophthora obtained in Italy from A. cordata. A Phytophthora cinnamomi strain was used for comparison. Host susceptibility to infection was determined as the lesion length after stem inoculation and the percentage of necrotized rootlets after soil infestation with inoculated millet seeds. The aggressiveness of the alder Phytophthora isolate was significantly higher in the two Alnus species than in the other hosts. Our results were confirmed with both methods of inoculation. Alnus cordata was consistently the most susceptible host species when compared with the other hardwoods. Damage by P. cinnamomi was severe, particularly after soil infestation tests. The most susceptible species were alders, chestnut and walnut. The test also suggests that alder Phytophthora is able to spread through infected seedlings of different hardwood species.

The natural presence of entomopathogenic nematodes (EPNs) has been investigated in the Piedmont region (Northern Italy) in areas infested by the Japanese beetle Popillia japonica. Thirty-nine out of 155 soil samples (25.2%) were positive for EPNs. Most of the samples contained only steinermatids (92.3%), 5.1% contained heterorhabditids, and one sample (2.6%) contained both genera. All the recovered isolates were identified at species level both morphologically and molecularly. Steinernema carpocapsae was the most abundant and it was mainly distributed in open habitats, such as perennial meadows, uncultivated soils, and cropland, characterized by sandy loam soil texture and acidic pH. Steinernema feltiae has been found associated mainly with closed habitats such as coniferous and deciduous woodland, characterized by sandy loam-texture and extremely acidic soil. The three isolates of Heterorhabditis bacteriophora were collected only in open habitats (perennial meadows and uncultivated fields) characterized by strongly acidic soils with sandy loam texture. The virulence of all EPN natural strains was evaluated by laboratory assays against P. japonica third-instar larvae collected during two different periods of the year (spring, autumn). The results showed that larval mortality was higher for pre-wintering larvae than post-wintering ones. The five more promising EPN isolates were tested in the semi-field assay in which H. bacteriophora natural strains have been shown to be more efficient in controlling P. japonica grubs. All of these results are finally discussed considering the use of these natural EPNs as biological control agents against P. japonica, within an eco-friendly perspective of management.

The Japanese beetle Popillia japonica Newman is a US and EU quarantine insect pest that has recently invaded northern Italy. Its ability to rapidly spread in new areas makes this insect a threat to agriculture. In the last decades, several trials on biological control of the Japanese beetle by entomopathogenic nematodes and fungi have been carried out with variable efficacy. However, the necessity of an integrated pest management approach to improve control has arisen. Long-lasting insecticide-treated nets (LLINs) have been used to control other agricultural pests with an attract-and-kill strategy. Here, we present results from laboratory evaluation of 2 LLINs, Storanet 1 (BASF TM ) and ZeroFly 1 (Vestergaard TM ), against P. japonica adults. Both were effective in killing the beetles; however, some differences emerged if different exposure times were compared: ZeroFly 1 always gave 100% mortality in tests from 5-s to 30-min exposure; Storanet 1 showed 100% mortality only with 30-min exposure and going down to 89%-99% mortality for 5-s to 15-min exposure. A description of the paralysis process occurring at 5-s exposure is given. Possible field application of LLINs within programs of integrated pest management is discussed. Integr Environ Assess Manag 2019;15:259-265. C 2018 SETAC

A Phytophthora was found associated with wilt and mortality of Italian alder (Alnus cordata) seedlings in a nursery in northern Tuscany, Central Italy. This disease is one of the major constraints to alder survival in northern Europe (3). Symptoms included sparse yellowish brown foliage with abnormally small leaves, dark stained necrosis of the bark at the collar level, and reduction of the root system due to the death of the tap root and lateral roots. These symptoms resemble those on chestnut, walnut, and oak plantlets colonized by P. cambivora. The diseased seedlings were 1 to 2 years old and were grown on both beds and soil. Tissue isolation from infected parts of the plants yielded a P. cambivora-like species in culture. Pure cultures were appressed and felty in appearance with sparse or no aerial mycelium when grown on V8 agar, carrot agar, or potato dextrose agar. Sporangia were ovoid, non-papillate, and averaged 51.8 μm in length and 36.6 μm in width (range: 45 to 60 μm and 30 to 40 μm). The isolates were homothallic with smooth-walled oogonia with a diameter ranging from 20 to 45 μm and with two-celled, amphigynous antheridia. Colonies showed rapid development at 25°C (mean radial growth = 6 mm/day), but at 30°C growth was strongly inhibited, unlike P. cambivora isolates previously collected in the same area, which were more thermophilic. The morpho-physiological features of the alder isolates resembled those of the Swedish variant of the alder Phytophthora (2). Identification was confirmed by C.M. Brasier (Forestry Authority Research Station, UK). Two-year-old alder seedlings (1.3 cm diameter, height 70 cm) grown in pots were wound-inoculated in the trunk. Six weeks after inoculation, symptoms were produced identical to those described above, as well as necrosis of the bark tissue varying in length from 0.5 to 3 cm. Isolations from diseased bark tissue yielded fungal colonies resembling those described above. The pathogen, described for the first time in England in 1995 (1), is now present throughout northern Europe. This is the first report for the Mediterranean region, which suggests that the fungus will cause disease in the drier and warmer climates of southern Europe. References: (1) C. M. Brasier et al. Plant Pathol. 44:999, 1995. (2) C. M. Brasier et al. Proc. Natl. Acad. Sci. USA 96:5878, 1999. (3) J. N. Gibbs et al. Eur. J. For. Pathol. 29:39, 1999.