Search results for "Chlorosis"
showing 10 items of 13 documents
Cultivar- and Wood Area-Dependent Metabolomic Fingerprints of Grapevine Infected by Botryosphaeria Dieback
2020
International audience; Botryosphaeria dieback is one of the most significant grapevine trunk diseases that affects the sustainability of the vineyards and provokes economic losses. The causal agents, Botryosphaeriaceae species, live in and colonize the wood of the perennial organs causing wood necrosis. Diseased vines show foliar symptoms, chlorosis, or apoplexy, associated to a characteristic brown stripe under the bark. According to the susceptibility of the cultivars, specific proteins such as PR-proteins and other defense-related proteins are accumulated in the brown stripe compared with the healthy woody tissues. In this study, we enhanced the characterization of the brown stripe and …
Impact of Bacterial Siderophores on Iron Status and Ionome in Pea
2020
National audience; Including more grain legumes in cropping systems is important for the development of agroecological practices and the diversification of protein sources for human and animal consumption. Grain legume yield and quality is impacted by abiotic stresses resulting from fluctuating availabilities in essential nutrients such as iron deficiency chlorosis (IDC). Promoting plant iron nutrition could mitigate IDC that currently impedes legume cultivation in calcareous soils, and increase the iron content of legume seeds and its bioavailability. There is growing evidence that plant microbiota contribute to plant iron nutrition and might account for variations in the sensitivity of pe…
Updated pest categorisation of Xylella fastidiosa
2018
Abstract Following a request from the European Commission, the EFSA Plant Health Panel updated its pest categorisation of Xylella fastidiosa, previously delivered as part of the pest risk assessment published in 2015. X. fastidiosa is a Gram‐negative bacterium, responsible for various plant diseases, including Pierce's disease, phony peach disease, citrus variegated chlorosis, olive quick decline syndrome, almond leaf scorch and various other leaf scorch diseases. The pathogen is endemic in the Americas and is present in Iran. In the EU, it is reported in southern Apulia in Italy, on the island of Corsica and in the Provence‐Alpes‐Côte d'Azur region in France, as well as in the Autonomous r…
Phytophthora taxon niederhauserii, a New Root and Crown Rot Pathogen of Banksia spp. in Italy
2009
In the last 10 years, various species of Banksia (family Proteaceae) endemic to Australia have been introduced into Italy where cultivation as flower plants is expanding. In the spring of 2003, a decline associated with root and basal stem rot of 2- to 3-year-old plants of Banksia speciosa R. Br., B. baxteri R. Br., and B. prionotes Lindl. grown in the ground was observed in a commercial nursery in Liguria (northern Italy). Aboveground symptoms included leaf chlorosis and wilt. Plants collapsed within 1 to 2 weeks after the appearance of leaf symptoms. A Phytophthora species was consistently isolated from roots and basal stem on BNPRAH selective medium (3). On V8 juice agar (V8A), axenic c…
Basil (Ocimum basilicum), a new host of Pepino mosaic virus.
2009
Pepino mosaic virus (PepMV), a member of the genus Potexvirus , was first described in 1980 on pepino ( Solanum muricatum ) and was later isolated from different wild species of the genus Solanum (formerly Lycopersicon ) (Soler et al ., 2002). PepMV has been reported in several European countries and in North America, causing disease in tomato. In July 2008, plants of basil ( Ocimum basilicum ) showing interveinal chlorosis on young leaves were observed in three greenhouses in Sicily, in the area where tomato plants were found to be infected by PepMV in 2005 (Davino et al ., 2006). The disease was transmitted mechanically to Nicotiana benthamiana , producing chlorotic spots and leaf deforma…
First Report of Tomato torrado virus Infecting Tomato in Italy.
2010
In 2009 and 2010, approximately 2% of plants had disease symptoms, including initial leaflet chlorosis that later developed into necrotic spots and general necroses along the leaflet. Fruit production on affected plants was substantially reduced and necroses were also present. Total RNA was extracted from five symptomatic plant samples using the RNeasy Plant Mini Kit (Qiagen, Hilden, Germany) and analyzed by reverse transcription (RT)-PCR with specific primer pair: TR2F (5′ GAAGGACGAAGAGCGACTG 3′), and TR2R (5′ AAGGTAGGTATGCGTTTGC 3′) (1). The primers amplified a 575-bp fragment within the coat protein Vp23 of Tomato torrado virus (ToTV). No RT-PCR products were observed when water or asym…
Occurrence of tomato pith necrosis caused by Pseudomonas marginalis in Italy.
2010
Dipartimento di Scienze e Tecnologie Fitosanitarie. Universita` degli Studi di Catania. Via Santa Sofia 100, 95123 Catania, ItalyIn 2006, a serious outbreak of tomato pith necrosis (TPN) with approxi-mately 90% disease incidence was observed in two greenhouses in Sicily.Adult fruiting plants showed chlorosis and slight wilting of shoot apices.Internalstem browning alongthe entire length oftheplant was observed.Pith tissues were soft but not rotted or hollowed. Only fluorescent colo-nies developed on King’s B medium (KB) after isolation from infected tis-sues. Ten pure isolates were all levan, oxidase, potato soft-rotting andarginine dihydrolase positive and were negative for tobacco hypersens…
First report of root and crown rot of sage caused by Phytophthora cryptogea in Italy
2019
Sages are cultivated as aromatic and ornamental plants in Italy and represent the common name of certain species of Salvia and Phlomis (family Lamiaceae). In Sicily (southern Italy) during the summer of 2001, ≈40% of 1,400 2-year-old landscape plants of S. leucantha Cav. (Mexican bush sage or velvet sage) showed symptoms of stunting, chlorosis, and gradual dieback or sudden wilt, which are associated with root and crown rot. Plants were supplied by a commercial nursery, transplanted from pots in the spring, and irrigated using a trickle system. Phytophthora was isolated consistently from roots and basal stems of symptomatic plants on a BNPRAH medium (2). The species was identified as P. cr…
Impairment of leaf hydraulics in young plants of Citrus aurantium (sour orange) infected by Phoma tracheiphila.
2007
Phoma trachephila (Petri) Kantschaveli et Gikachvili causes dieback of several Citrus species. The impact of this fungus on leaf hydraulics was studied in Citrus aurantium L. (sour orange) with the aim of identifying the primary mechanism of damage to leaves. Leaves inoculated with a conidial suspension were measured for conductance to water vapor (gL) and specific hydraulic conductance (Kleaf) every 3 days after inoculation. The earliest symptom of infection consisted of vein chlorosis. Functional vein density (FVD) was monitored and microscopic observations were made of major vein conduits. Impairment of vein hydraulics started 25 days after inoculation with a losses of Kleaf of 40% and g…
Nutrient disturbance through manganese accumulation in Douglas fir
1998
Abstract The disturbance of the nutrient balance induced by a surplus of manganese is discussed as the main cause of the disease striking Douglas fir. In this context a close examination of the iron balance is of great interest. Despite high total iron content, damaged Douglas fir show symptoms similar to that of an iron deficiency chlorosis in which the redox state of iron seems to be affected (physiological iron-deficiency). The first results of the project strengthen this assumption. During this research project iron dependent systems (e.g. activities of iron dependent enzymes, structure of chloroplasts etc.) are being scrutinised by the use of various microtechnical and chemical methods…