Search results for " tomato."
showing 10 items of 39 documents
Mixed infection of Pectobacterium carotovorum subsp. Carotovorum and P. carotovorum subsp. Brasiliensis in tomato stem rot in Italy
2016
Grafted tomato plants grown in a soilless culture system in heated greenhouses in Sicily were affected by stem rot disease. Symptoms consisted of dark brown longitudinal discoloration of the basal part of the stem and petioles. Longitudinal sections of the stem revealed brown watersoaked or soft-rotted pith tissue and internal vascular discoloration. Bacterial isolates with two different colony morphologies were obtained from symptomatic tissues. Isolates were identified as Pectobacterium spp. on the basis of biochemical and molecular analyses. The analysis of the 16S rRNA gene sequence and of the concatenated sequences of the housekeeping genes rpoS and pgi revealed that the isolates of th…
Comparative Chemical Compositions of Fresh and Stored Vesuvian PDO "Pomodorino Del Piennolo" Tomato and the Ciliegino Variety
2018
The Vesuvian Piennolo cherry tomato (Lycopersicon esculentum Miller) (PdP) is an old and typical variety grown in the Campania region (Italy). PdP is referred to as a long-storage tomato due to its thick and coriaceous skin that allows long post-harvest storage and it has been granted Protected Designation of Origin (PDO) status since 2009. In this study, the chemical composition, focusing in particular on organic acids, antioxidant molecules and volatile compounds, were investigated in PdP and compared to another typical variety in Campania, the Ciliegino tomato (CIL). Chemical characterization was evaluated for both the CIL and PdP varieties during storage in the same environmental condit…
Pseudomonas corrugata contains a conserved N-acyl homoserine lactone quorum sensing system; its role in tomato pathogenicity and tobacco hypersensiti…
2007
Pseudomonas corrugata is a phytopathogenic bacterium, causal agent of tomato pith necrosis, yet it is an ubiquitous bacterium that is part of the microbial community in the soil and in the rhizosphere of different plant species. Although it is a very heterogeneous species, all the strains tested were able to produce short chain acyl homoserine lactone (AHL) quorum sensing signal molecules. The main AHL produced was N-hexanoyl-l-homoserine lactone (C6-AHL). An AHL quorum sensing system, designated PcoI/PcoR, was identified and characterized. The role of the quorum sensing system in the expression of a variety of traits was evaluated. Inactivation of pcoI abolished the production of AHLs. The…
N-acyl-homoserine-lactone quorum sensing in tomato phytopathogenic Pseudomonas spp. is involved in the regulation of lipodepsipeptide production
2012
Pseudomonas corrugata and Pseudomonas mediterranea are two closely related phytopathogenic bacteria both causal agents of tomato pith necrosis. P. corrugata produces phytotoxic and antimicrobial cationic lipodepsipeptides (LDPs) which are thought to act as major virulence factors. Previous studies have demonstrated that P. corrugata CFBP 5454 has an N-acyl homoserine lactone (AHL) quorum sensing (QS) system PcoI/PcoR and that LDP production occurs at high population densities. No molecular studies on virulence have thus far been reported for P. mediterranea. In this study, we show that P. mediterranea also produces LDPs as well as possessing an AHL-dependent QS system, designated PmeI/PmeR,…
Bioprospecting of Beneficial Bacteria Traits Associated With Tomato Root in Greenhouse Environment Reveals That Sampling Sites Impact More Than the R…
2021
Tomato is subject to several diseases that affect both field- and greenhouse-grown crops. To select cost-effective potential biocontrol agents, we used laboratory throughput screening to identify bacterial strains with versatile characteristics suitable for multipurpose uses. The natural diversity of tomato root–associated bacterial communities was bioprospected under a real-world environment represented by an intensive tomato cultivation area characterized by extraseasonal productions in the greenhouse. Approximately 400 tomato root–associated bacterial isolates, in majority Gram-negative bacteria, were isolated from three compartments: the soil close to the root surface (rhizosphere, R), …
Simultaneous detection of the seven main tomato-infecting RNA viruses by two multiplex reverse transcription polymerase chain reactions
2012
Cucumber mosaic virus, Tomato spotted wilt virus, Tomato mosaic virus, Tomato chlorosis virus, Pepino mosaic virus, Torrado tomato virus and Tomato infectious chlorosis virus cause serious damage and significant economic losses in tomato crops worldwide. The early detection of these pathogens is essential for preventing the viruses from spreading and improving their control. In this study, a procedure based on two multiplex RT-PCRs was developed for the sensitive and reliable detection of these seven viruses. Serial dilutions of positive controls were analysed by this methodology, and the results were compared with those obtained by ELISA and singleplex versions of RT-PCR. The multiplex and…
Oviposition deterrence and repellent activities of selected essential oils against Tuta absoluta Meyrick (Lepidoptera: Gelechiidae): laboratory and g…
2022
AbstractTuta absoluta, an invasive pinworm characterized by high reproductive potential and adaptation to different agroecological conditions, cause serious damage to tomato crops. Chemical control with synthetic insecticides is widely used to control this pest, although pesticides exhibit side effects on non-target organisms and negatively impact the environment, with the occurrence of resistance to some active substances in the target pest. The use of essential oils (EOs) from aromatic or officinal plants could represent an environmentally safe control method, alternative to synthetic insecticide application. In this work we investigated the effect of EOs from Spanish oregano, laurel, bas…
Complete sequence, genotyping and comparative analysis of Pepino mosaic virus discovered isolates from Italy
2011
Pepino mosaic virus (PepMV) causes economic damage to the tomato industry worldwide. In Italy, the virus is endemic in Sicily, an important tomato-production region, and a new outbreak has been recorded in Sardinia after the first PepMV appearance in 2001. Italian PepMV isolates from these two geographically distant regions were molecularly characterized and the complete nucleotide sequence of four isolates was determined by walking primer strategy. The complete nucleotide and deduced amino acid sequences were analyzed and compared with published PepMV sequences. Italian isolates belong to the PepMV-Ch2 strain and had 97.2% to 98.5% identity with those of the reference PepMV-Ch2 deposited i…
Tomato brown rugose fruit virus: A pathogen that is changing the tomato production worldwide
2022
Tomato (Solanum lycopersicum L., family Solanaceae) represents one of the most cultivated horticultural crops worldwide, with over 5 million hectares of cultivated area and more than 182 million tons of tomato produced globally. Nevertheless, monoculture conditions, intensive selection, domestication throughout the last decades, international trade of infected propagating material and climate changes intensely favoured the establishment of many pathogens and the rapid spread of new diseases, allowing organisms to establish in new and unfavourable environments. Among different biotic agents, viruses are the most dangerous, because of their rapid diffusion and production losses. Here, we revi…