23 research outputs found
OSTREOPSIS OVATA FUKUYO (1981): MONITORING
species belong to the genus Ostreopsis Schmidt, all of these are toxic, and Ostreopsis ovata Fukuyo is one of these.
O. ovata is different from O. siamensis [5] Schmidt and O. lenticularis Fukuyo because it is smaller, it has more breakable thecal plates and it has a straight and short apical pore
Pomegranate: Postharvest Fungal Diseases and Control
Due to well-known nutraceutical properties, pomegranate (Punica granatum L.) cultivation is recently increasing in various areas of the world including Italy. Fungal diseases are the major causes of postharvest yield and economic losses. Most of the fungi infect pomegranates in the field during the blooming stage remaining latent until fruit ripening, others infect fruit during harvest and postharvest handling through rind injuries. Main postharvest fungal diseases of pomegranates are gray and blue molds caused by Botrytis spp. and Penicillium spp., respectively, black heart and black spot due to Alternaria spp., anthracnose related to species ascribable to Colletotrichum genus, and Coniella rot, due to Coniella granati. Few fungicides are allowed for pre- and postharvest treatments, making it extremely difficult to control fungal infections. In this scenario, especially in organic fruit production, alternative control means may be a desirable solution to reduce pomegranate losses during the production chain. This chapter focuses on the most important postharvest diseases of pomegranates and possible strategies and means to reduce spoilage
Fungal pathogens associated with harvested table grapes in Lebanon, and characterization of the mycotoxigenic genera
Table grapes are exposed to fungal infections before and after harvest. In
particular, Aspergillus, Penicillium, and Alternaria can cause decays and contamination by mycotoxins. The main fungi affecting Lebanese table grapes after harvest were
assessed as epiphytic populations, latent infections, and rots. Effects of storage with
and without SO2 generating pads were also evaluated. Representative isolates of toxigenic genera were characterised, and their genetic potential to produce ochratoxin A,
fumonisins, and patulin was established. The epiphytic populations mainly included
wound pathogens (Aspergillus spp. and Penicillium spp.), while latent infections and
rots were mostly caused by Botrytis spp. The use of SO2 generating pads reduced the
epiphytic populations and rots, but was less effective against latent infections. Characterization of Aspergillus, Penicillium, and Alternaria isolates showed that A. tubingensis, P. glabrum, and A. alternata were the most common species. Strains of A. welwitschiae and P. expansum were also found to be genetically able to produce, respectively, ochratoxin A plus fumonisins and patulin. These data demonstrate the need for effective measures to prevent postharvest losses caused by toxigenic fung
Main postharvest fungal diseases of pomegranate fruit in southern Italy
Pomegranate (Punica granatum L.) is an increasingly important crop in Apulia, where most of the Italian production occur. The main yield problem is related to postharvest losses caused by fungi. The present research was conducted using fruit of two cultivars (Mollar de Elche and Wonderful) with different characteristics, from local markets, orchards, and packinghouses in the province of Lecce (southern Italy). The main fungi observed on stored pomegranate fruit were Botrytis sp., Pilidiella granati, Alternaria spp., Penicillium spp. (s.l.), Colletotrichum acutatum, and Cytospora punicae. The early three pathogens infected fruit through the calyx area during blossom, and then spread to the entire pomegranate. Moreover, Botrytis sp. was responsible for harmful latent infections, especially during the cold storage, which was a critical stage even for C. acutatum. Two different species of Alternaria, causing âblack heartâ or âblack spotâ, were identified: A. alternata and A. arborescens. The main Penicillium spp. s.s. observed were P. glabrum, P. adametzioides, and P. brevicompactum. Few isolates of Talaromyces albobiverticillius were also present. These fungi, that share very similar macroscopic characteristics, were mainly present on decayed stamens and wounds. In the present study, P. granati and C. punicae, predominantly recorded as etiological agents of pomegranate trunk canker, were isolated from fruit
Postharvest Diseases of Pomegranate: Alternative Control Means and a Spiderweb Effect
The pomegranate is a fruit known since ancient times for its beneficial properties. It has recently aroused great interest in the industry and among consumers, leading to a significant increase in demand. Consequently, its cultivation has been boosted all over the world. The pomegranate crop suffers considerable yield losses, especially at the postharvest stage, because it is a âminor cropâ with few permitted control means. To control latent (Alternaria spp., Botrytis spp., Coniella spp., Colletotrichum spp., and Cytospora spp.) and wound (Aspergillus spp., Penicillium spp., and Talaromyces spp.) fungal pathogens, different alternative compounds, previously evaluated in vitro, were tested in the field on pomegranate cv. Wonderful. A chitosan solution, a plant protein hydrolysate, and a red seaweed extract were compared with a chemical control treatment, all as preharvest (field application) and postharvest treatments and their combinations. At the end of the storage period, the incidence of stamen infections and external and internal rots, and the severity of internal decay were evaluated. Obtained data revealed that pre- and postharvest application of all substances reduced the epiphytic population on stamens. Preharvest applications of seaweed extract and plant hydrolysate were the most effective treatments to reduce the severity of internal pomegranate decays. Furthermore, the influence of spider (Cheiracanthium mildei) cocoons on the fruit calyx as a possible barrier against postharvest fungal pathogens was assessed in a âMollar de Elcheâ pomegranate organic orchard. Compared to no-cocoon fruit (control), the incidence of infected stamens and internal molds in those with spiderwebs was reduced by about 30%, and the mean severity of internal rots was halved. Spiderwebs analyzed via Scanning Electron Microscopy (SEM) disclosed a layered, unordered structure that did not allow for the passage of fungal spores due to its mean mesh size (1 to 20 ”m ca). The aims of this research were (I) to evaluate alternative compounds useful to control postharvest pomegranate decays and (II) to evaluate the effectiveness of spiders in reducing postharvest fungal infections by analyzing related mechanisms of action. Alternative control means proposed in the present work and calyx spider colonization may be helpful to reduce postharvest pomegranate diseases, yield losses, and waste production in an integrated control strategy, satisfying organic agriculture and the planned goals of Zero Hunger Challenge launched by the United Nations
Occurrence of Sheraphelenchus sucus (Nematoda: Aphelenchoidinae) and Panagrellus sp. (Rhabditida: Panagrolaimidae) Associated with Decaying Pomegranate Fruit in Italy
Two different nematode species were recovered from pomegranate decaying fruit in two localities in Southern Italy: The mycetophagus nematode Sheraphelenchus sucus and a bacterial feeder nematode belonging to the Panagrolaimidae (Rhabditida) family. Morphometrics of the Italian population of S. sucus closely resemble that of the type population, whereas some differences were found when compared with another population from Iran. Molecular characterization of the Italian S. sucus using the 18S rRNA gene, D2-D3 expansion domains of the 28S rDNA, the ITS region, and the partial mitochondrial COI were carried out. Sequences of the 18S rRNA gene, the D2-D3 domains, and the ITS were analyzed using several methods for inferring phylogeny to reconstruct the relationships among Sheraphelenchus and Bursaphelenchus species. The bacterial feeder Panagrellus sp. was characterized at the molecular level only. The D2-D3 expansion domains and ITS sequences of this Italian panagrolaimid were determined. The D2-D3 sequences of the Italian panagrolaimid showed 99% similarity with the corresponding sequence of Panagrellus sp. associated with Rhynchophorus ferrugineus. This is the first report on the tritrophic association of S. sucus and Rhabditida that uses both insects and pomegranate fruit as hosts
âEctomosphereâ: 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 endosymbiontsâ 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 Unionâs Horizon 2020 research and innovation programme under Grant Agreements No. 635646-POnTE âPest Organisms Threatening Europeâ, No. 727987-XF-ACTORS âXylella Fastidiosa Active Containment Through a multidisciplinary-Oriented Research Strategyâ, Grant number 952337-MycoTWIN âEnhancing Research and Innovation Capacity of Tubitak MAM Food Institute on Management of Mycotoxigenic Fungi and Mycotoxinsâ, and CURE-Xf, H2020-Marie Sklodowska-Curie ActionsâResearch 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 Unionâs StopMedWaste âInnovative Sustainable technologies TO extend the shelf-life of Perishable MEDiterranean fresh fruit, vegetables and aromatic plants and to reduce WASTEâ a PRIMA project ID: 1556. European Unionâs Euphresco BasicS âBasic substances as an environmentally friendly alternative to synthetic pesticides for plant protectionâ 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 âLaboratory network for the selection, characterisation and conservation of germplasm and for preventing the spread of economically-relevant and quarantine pests (SELGE) No. 14â, founded by the Apulia Region, PO FESR 2007â2013âAxis I, Line of intervention 1.2., Action 1.2.1; Research for Innovation (REFIN) POR Puglia 2014â2020 Project: 8C6E699D, and PON AIM, COD. AIM 1809249-AttivitĂ 1 Linea 1
First report of Pilidiella granati causing postharvest fruit rot on pomegranate in southern Italy
In 2015, rot symptoms were observed during storage on pomegranate fruit (Punica granatum L.) cvs Wonderful and Mollar de Elche from a packinghouse in Apulia (Southern Italy). Symptoms, observed on 26% of fruit, consisted of circular brownish-yellow lesions, beginning in the crown area and quickly expanding to entire fruit, with softening of the tissues including arils. Tissue portions were cut from surface-sterilized fruit and incubated on semi-selective PDA at 28±1°C in the dark. Colonies were white to creamy, leathery, and covered by abundant dark-greenish- brown to black spherical pycnidia (80-140 ÎŒm in diameter) with thin membranous walls. Hyphae were septate, and conidia hyaline, one-celled, 10-17.5Ă2-5 ÎŒm, ellipsoid to fusiform, straight or slightly curved. These characteristics corresponded to Pilidiella granati (Saccardo) (syn. Coniella granati Sacc.) Petr. & Syd.). For molecular confirmation, fungal DNA was amplified using universal primers ITS5/ITS4. BLAST analysis of the 506 bp amplicon (GenBank accession No. KU821701) showed 100% identity with other P. granati ITS sequences. For pathogenicity tests, surface-sterilized fruit of both cvs were wounded (5Ă5 mm), inoculated by a mycelial plug and incubated as reported above. Sterile plugs were used as controls. Lesions were visible after five days only on inoculated fruit. The re-isolated fungus corresponded to P. granati, which was reported as pomegranate postharvest rot agent in Spain (Palou et al., 2010) and recently associated with a crown rot in Italy (Pollastro et al., 2016). To our knowledge, this is the first report of P. granati rot on harvested pomegranate fruit in Southern Italy that might represent a serious threat for marketing of this promising crop