Climate changes and nematodes: expected effects and perspectives for plant protection

Some factors interfering with plant protection from phytoparasitic nematodes are reviewed in the light of changes brought about by the global warming in action. The mechanisms mainly concern changes in temperature and water regimes. The effects of climate changes on the epidemiology and management of the main phytoparasitic species occurring in Mediterranean environments include the alteration of the reproductive cycles due to plants productivity, the geographic dispersion by more northern or higher altitude shifts, the spread of vectors. Other related indirect mechanisms are feedback effects due to the reactions of cultivated species or weeds, and those related to natural enemies. The potential management of some operational tools are briefly discussed, including the development and application of models and monitoring. An exemple of modeling changes induced by increasing temperatures on the carrot cyst nematode Heterodera carotae is briefly discussed

Detection and quantification of Aspergillus section Flavi spp. in stored peanuts by real-time PCR of nor-1 gene, and effects of storage conditions on aflatoxin production

Aspergillus flavus and A. parasiticus are the main species from section Flavi responsible for aflatoxin accumulation in stored peanuts. A real-time PCR (RT-PCR) system directed against the nor-1 gene of the aflatoxin biosynthetic pathway as target sequence was applied to monitor and quantify Aspergillus section Flavi population in peanuts. Kernels were conditioned at four water activity (aW) levels and stored during a 4-month period. The quantification of fungal genomic DNA in naturally contaminated peanut samples was performed using TaqMan fluorescent probe technology. Sensitivity tests demonstrated that DNA amounts accounting for a single conidium of A. parasiticus RCP08300 can be detected. A standard curve relating nor-1 copy numbers to colony forming units (cfu) was constructed. Counts of species of Aspergillus section Flavi from unknown samples obtained by molecular and conventional count (CC) methodologies were compared. A correlation between cfu data obtained by RT-PCR and CC methods was observed (r=0.613; p<0.0001); and the former always showed values higher by 0.5-1 log units. A decrease of fungal density was observed throughout the storage period, regardless of the quantification methodology applied. Total aflatoxin levels ranging from 1.1 to 200.4ng/g were registered in peanuts conditioned at the higher aW values (0.94-0.84 aW).The RT-PCR assay developed appears to be a promising tool in the prediction of potential aflatoxigenic risk in stored peanuts, even in case of low-level infections, and suitable for rapid, automated and high throughput analysis. © 2010.Fil: Passone, Maria Alejandra. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigación en Micología y Micotoxicología. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación en Micología y Micotoxicología; ArgentinaFil: Rosso, Laura Cristina. Istituto per la Protezione delle Piante. Consiglio Nazionale delle Ricerche; ItaliaFil: Ciancio, Aurelio. Istituto per la Protezione delle Piante. Consiglio Nazionale delle Ricerche; ItaliaFil: Etcheverry, Miriam Graciela. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Modeling Root-Knot Nematode Regulation by the Biocontrol Fungus Pochonia chlamydosporia

Two models of increasing complexity were constructed to simulate the interactions between the root-knot nematode (RKN) Meloidogyne incognita and the biocontrol fungus Pochonia chlamydosporia var. catenulata in a rhizosphere microcosm. The models described discrete population dynamics at hourly rates over a 6-month period and were validated using real parasitism and nematode or fungus data. A first, general Pochonia–nematode–root model (GPNR) used five functions and 16 biological constants. The variables and constants describing the RKN life cycle included the rates of egg production, hatching, juvenile (J2), and mature female development, including root or nematode self-density-dependent factors. Other constants accounted for egg parasitism, nematode-induced root losses, growth, and mortalities. The relationship between nematodes and fungal propagules showed density dependence and cyclic variations in time, including an attractor on the propagules and J2 phases space. The simulations confirmed a P. chlamydosporia optimal initial density of 5 · 103 propagules · cc soil-1, as usually applied in assays. The constants used in GPNR showed adherence to the nematode biology, with 103 eggs per egg mass, a 10-day average lifespan of J2, with 2 days required to enter roots, and adult lifespan lasting 24 days. The fungus propagule lifespan was 25 days, with an average feeder root lifespan lasting around 52 days. A second, more complex Pochonia–nematode–root detailed model (GPNRd) was then constructed using eight functions and 23 constants. It was built as GPNR did not allow the evaluation of host prevalence. GPNRd allowed simulations of all RKN life stages and included non-parasitic and parasitic fungus population fractions. Both GPNR and GPNRd matched real J2 and fungus density data observed in a RKN biocontrol assay. Depending on the starting conditions, simulations showed stability in time, interpreted as effective host regulation. GPNRd showed a fungus cyclic relationship with the J2 numbers, with prevalence data close to those observed (38.3 vs. 39.4%, respectively). This model also showed a further density-independent nematode regulation mechanism based on the P. chlamydosporia switch from a non-parasitic to a parasitic trophic behavior. This mechanism supported the biocontrol of M. incognita, also sustained by a concomitant increase of the root density

Sustainable strategies for management of the “false root-knot nematode” Nacobbus spp.

The genus Nacobbus, known as the false root-knot nematode, is native to the American continent and comprises polyphagous species adapted to a wide range of climatic conditions. Alone or in combination with other biotic and abiotic factors, Nacobbus spp. can cause significant economic yield losses on main food crops such as potato, sugar beet, tomato, pepper and bean, in South and North America. Although the genus distribution is restricted to the American continent, it has quarantine importance and is subject to international legislation to prevent its spread to other regions, such as the European Union. The management of Nacobbus spp. remains unsatisfactory due to the lack of information related to different aspects of its life cycle, survival stages in the soil and in plant material, a rapid and reliable diagnostic method for its detection and the insufficient source of resistant plant genotypes. Due to the high toxicity of chemical nematicides, the search for alternatives has been intensified. Therefore, this review reports findings on the application of environmentally benign treatments to manage Nacobbus spp. Biological control strategies, such as the use of different organisms (mainly bacteria, fungi and entomopathogenic nematodes) and other eco-compatible approaches (such as metabolites, essential oils, plant extracts, phytohormones and amendments), either alone or as part of a combined control strategy, are discussed. Knowledge of potential sources of resistance for genetic improvement for crops susceptible to Nacobbus spp. are also reported. The sustainable strategies outlined here offer immediate benefits, not only to counter the pathogen, but also as good alternatives to improve crop health and growth

“Ectomosphere”: Insects and Microorganism Interactions

This study focuses on interacting with insects and their ectosymbiont (lato sensu) microorganisms for environmentally safe plant production and protection. Some cases help compare insect-bearing, -driving, or -spreading relevant ectosymbiont microorganisms to endosymbionts’ behaviour. Ectosymbiotic bacteria can interact with insects by allowing them to improve the value of their pabula. In addition, some bacteria are essential for creating ecological niches that can host the development of pests. Insect-borne plant pathogens include bacteria, viruses, and fungi. These pathogens interact with their vectors to enhance reciprocal fitness. Knowing vector-phoront interaction could considerably increase chances for outbreak management, notably when sustained by quarantine vector ectosymbiont pathogens, such as the actual Xylella fastidiosa Mediterranean invasion episode. Insect pathogenic viruses have a close evolutionary relationship with their hosts, also being highly specific and obligate parasites. Sixteen virus families have been reported to infect insects and may be involved in the biological control of specific pests, including some economic weevils. Insects and fungi are among the most widespread organisms in nature and interact with each other, establishing symbiotic relationships ranging from mutualism to antagonism. The associations can influence the extent to which interacting organisms can exert their effects on plants and the proper management practices. Sustainable pest management also relies on entomopathogenic fungi; research on these species starts from their isolation from insect carcasses, followed by identification using conventional light or electron microscopy techniques. Thanks to the development of omics sciences, it is possible to identify entomopathogenic fungi with evolutionary histories that are less-shared with the target insect and can be proposed as pest antagonists. Many interesting omics can help detect the presence of entomopathogens in different natural matrices, such as soil or plants. The same techniques will help localize ectosymbionts, localization of recesses, or specialized morphological adaptation, greatly supporting the robust interpretation of the symbiont role. The manipulation and modulation of ectosymbionts could be a more promising way to counteract pests and borne pathogens, mitigating the impact of formulates and reducing food insecurity due to the lesser impact of direct damage and diseases. The promise has a preventive intent for more manageable and broader implications for pests, comparing what we can obtain using simpler, less-specific techniques and a less comprehensive approach to Integrated Pest Management (IPM).The present work acknowledges the support from: European Union’s Horizon 2020 research and innovation programme under Grant Agreements No. 635646-POnTE “Pest Organisms Threatening Europe”, No. 727987-XF-ACTORS “Xylella Fastidiosa Active Containment Through a multidisciplinary-Oriented Research Strategy”, Grant number 952337-MycoTWIN “Enhancing Research and Innovation Capacity of Tubitak MAM Food Institute on Management of Mycotoxigenic Fungi and Mycotoxins”, and CURE-Xf, H2020-Marie Sklodowska-Curie Actions—Research and Innovation Staff Exchange. Reference number: 634353, coordinated by CIHEAM Bari. The EU Funding Agency is not responsible for any use that may be made of the information it contains. European Union’s StopMedWaste “Innovative Sustainable technologies TO extend the shelf-life of Perishable MEDiterranean fresh fruit, vegetables and aromatic plants and to reduce WASTE” a PRIMA project ID: 1556. European Union’s Euphresco BasicS “Basic substances as an environmentally friendly alternative to synthetic pesticides for plant protection” project ID: 2020-C-353. The work was partially carried out in the framework of the National Projects: RIGENERA, granted by MASAF n. 207631, 9 May 2022, and GENFORAGRIS, granted by MASAF n. 207631, 9 May 2022; and regional projects “Laboratory network for the selection, characterisation and conservation of germplasm and for preventing the spread of economically-relevant and quarantine pests (SELGE) No. 14”, founded by the Apulia Region, PO FESR 2007–2013—Axis I, Line of intervention 1.2., Action 1.2.1; Research for Innovation (REFIN) POR Puglia 2014–2020 Project: 8C6E699D, and PON AIM, COD. AIM 1809249-Attività 1 Linea 1

Erratum to: Discussion: A New Method of Salvaging Breast Reconstruction After Breast Implant Using Negative-Pressure Wound Therapy and Instillation (Aesthetic Plastic Surgery, (2017), 41, 2, (466-467), 10.1007/s00266-016-0734-6)

The first author's given name and family name were inverted. The correct order is Francesco Ciancio. The original article was corrected

Editorial : Harnessing useful rhizosphere microorganisms for pathogen and pest biocontrol - second edition

There is a worldwide interest in the exploitation of beneficial plant-associated microorganisms as an alternative to pesticides for pest and disease management. It is underpinned by practical and social reasons, including safety of consumers, farmers, and field workers, as well as the need for sustainable practices safeguarding the environment and protecting its biodiversity. Cost of conventional pesticides and the insurgence of resistance in pests also re-direct farmers’ choice toward safer approaches. This trend is observed also in fast-growing population economies, propelling the global demand for eco-sustainable technologies. Understanding the role of rhizosphere microorganisms in the control of pests and diseases appears as a growing research field, as shown by the sharp increase of studies carried out during the period 2000–2019. The number of records retrieved through a Google Scholar query with keywords “microorganisms,” “control,” “pest,” and “diseases” increased from around 5000 (2000–2005) to 8500 and >20,000 (2006–2010 and 2011–2019, respectively), when the term “rhizosphere” was added. Without the latter the records instead lowered from around 17,000 to 15,000 in the last period (interrogation dated August 2, 2019). However, in spite of this increased interest in rhizosphere ecology managing and exploiting living organisms to regulate or control other noxious species still remains a complex task. Detailed data on interacting variables and processes are needed, as their final result often differs significantly from the simple sum of effects. Any information boosting our capacity to solve problems related to safer plant protection is, therefore, more than welcome