Search

Meloidogyne graminicola is one of the most harmful organisms in rice cultivation throughout the world. This pest was detected for the first time in mainland Europe (Northern Italy) in 2016 and was subsequently added to the EPPO Alert List. To date, few methods are available for the control of M. graminicola and new solutions are required. In 2019, field trials using rice plants as trap crops were performed in a Lombardy region rice field where five plots for three different management approaches were staked out: (i) Uncultivated; (ii) Treated: three separate cycles of rice production where plants were sown and destroyed each time at the second leaf stage; (iii) Control: rice was sown and left to grow until the end of the three cycles in treated plots. The results showed that in the treated plots, the nematode density and the root gall index were lower than for the other two management approaches. Moreover, the plant population density and rice plant growth were higher than the uncultivated and control plots. In conclusion, the use of the trap crop technique for the control of M. graminicola gave good results and thus it could be a new phytosanitary measure to control this pest in rice crop areas. [ABSTRACT FROM AUTHOR]

Simple Summary: The Japanese beetle Popillia japonica is considered one of the most harmful organisms in the world for crops and the urban landscape. Popillia japonica spends most of its life cycle in the soil as a larva. At this stage, this beetle is more susceptible to biological control agents like entomopathogenic nematodes, which are obligate parasites of main soil-inhabiting insects, killing their host in just a few days. In 2014, P. japonica was detected in Northern Italy between the Piedmont and Lombardy regions. This research aims to investigate the natural occurrence of indigenous and locally adapted entomopathogenic nematodes along the Piedmont part of the Ticino river and test the most performing of them via bioassays. Natural isolates were recovered from 39 out of the 155 soil samples collected. The virulence of all entomopathogenic nematodes assessed by laboratory and semi-field assays highlighted that two isolates resulted in more efficiency in controlling P. japonica grubs. This result is very encouraging, and the use of these natural biocontrol agents against this pest is a fundamental component of eco-friendly management. 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. [ABSTRACT FROM AUTHOR]

Soil invertebrates represent almost a quarter of the total diversity of living organisms and their activity affects the entire soil ecological process. The choice of adequate thinning systems may differently affect soil nematode and microarthropod biodiversity in artificial black pinewoods. In this work, the results of the impact of different thinnings on the structure of nematode and microarthropod communities was reported. In a short-term experiment, thinning from below and selective thinning were compared to unmanaged stands to provide indications at the regional scale in central Italy. Soil nematode and microarthropod biodiversity was explored by examining community structure, assessing biodiversity. The interaction between environmental variables (crown volume, Photosynthetically Active Radiation, soil texture, soil temperature, and moisture) with taxa abundance of nematodes and microarthropods were also reported. The results indicated that the effects of thinning practices were temporary and varied between years. Soil nematode community shifted during the first and third years of thinning managements only in the Pratomagno site, while soil microarthropod community shifted in both sites only in the second year. The total nematode abundance was minimally affected by thinning practices, while the nematode community composition showed a decrease of omnivores and predators in the first years. Soil indicators showed inconsistent results. In microarthropods, mites and collembola were the least affected by thinning in terms of abundance and species biodiversity, while eu-edaphic taxa of Chilopoda, Diplopoda, and Pauropoda were not influenced by thinning, hemi-edaphic and epi-edaphic taxa of Coleoptera, Diptera, Hymenoptera, Tysanoptera, and Hemiptera were negatively affected. Soil indicators such as Shannon-Weiner and Simpson indices and soil biological quality (QBS-ar) improved in thinning from below in both sites. Soil temperature and moisture were the main driving factors in affecting soil nematode and microarthropods communities. Thinning from below probably allowed a more rapid recovery than selective thinning. [ABSTRACT FROM AUTHOR]