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Leaf Blight (leaf + blight)
Selected AbstractsInfluences of Northern Leaf Blight on corn silage fermentation quality, nutritive value and feed intake by sheepANIMAL SCIENCE JOURNAL, Issue 4 2010Peng WANG ABSTRACT This study examined the differences between non-inoculated (control) corn and Northern Leaf Blight (NLB)-damaged corn (inoculated corn); dry matter (DM) yield, silage fermentation quality, nutritive value and feed intake by sheep were compared. Leaf, stem and grain dry weights and gross yield of inoculated corn were significantly (P < 0.05) decreased compared with control corn. The contents of water-soluble carbohydrate and nitrogen-free extract (NFE) were decreased in inoculated corn compared with control corn. Silage made from both inoculated and control corn showed good fermentation quality. The digestibility of DM, organic matter, ether extract, NFE, and energy of silage made from inoculated corn were significantly (P < 0.05) lower, and contents of total digestible nutrients (TDN) and digestible energy (DE) were also significantly (P < 0.05) lower compared with silage made from the control corn. DM intake showed no significant discrepancy between the two types of silage. TDN and DE intakes from inoculated silage were significantly (P < 0.05) lower compared with control silage. From the above results it was shown that NLB caused a decrease in DM yield and NFE content in corn and a decrease in the nutritive value and feed intake of silage. [source] Characterization and Identification of Asexual Strains of Pythium Associated with Root Rot of Rose in JapanJOURNAL OF PHYTOPATHOLOGY, Issue 9 2003K. Kageyama Abstract This study was conducted to survey the distribution of asexual isolates of Pythium in rose production and to characterize and identify them. Asexual isolates with proliferating globose sporangia belong to group P according to the key of van der Plaats-Niterink (1981; Monograph of the genus Pythium. Studies in Mycology, Vol. 21, Centraalbueau Voor Schimmelcultures, Baarn, The Netherlands). Group P isolates were recovered from rotted roots of both cutting and miniature roses cultured in rock wool and ebb-and-flow culture systems, respectively, throughout the main rose production area of Japan. The typical feature of the P group isolates was that they could grow fast at high temperature, at least 30 mm per 24 h at 35°C. There was no difference between the P group isolates and P. helicoides in morphology and size of sporangia and sporangial germination mode. The symptoms caused by the group P isolates were root rot, followed by leaf blight and plant death in severe cases. In restriction fragment length polymorphism analysis of the rDNA-ITS region, the banding patterns with five of six enzymes were identical between group P and P. helicoides, the only difference being seen with HhaI. In direct amplification analysis of minisatellite-region DNA with M13 primer, group P and P. helicoides shared three of five distinct bands. In contrast, P. oedochilum and P. ostracodes showed different banding patterns except for each one band. The results suggest that the group P isolates obtained from rose root rot may be asexual strains of P. helicoides. [source] Alternaria spp.: from general saprophyte to specific parasiteMOLECULAR PLANT PATHOLOGY, Issue 4 2003Bart P. H. J. Thomma SUMMARY Alternaria species are mainly saprophytic fungi. However, some species have acquired pathogenic capacities collectively causing disease over a broad host range. This review summarizes the knowledge on pathogenic strategies employed by the fungus to plunder the host. Furthermore, strategies employed by potential host plants in order to ward off an attack are discussed. Taxonomy:Alternaria spp. kingdom Fungi, subkingdom Eumycotera, phylum Fungi Imperfecti (a non-phylogenetic or artificial phylum of fungi without known sexual stages whose members may or may not be related; taxonomy does not reflect relationships), form class Hypomycetes, Form order Moniliales, form family Dematiaceae, genus Alternaria. Some species of Alternaria are the asexual anamorph of the ascomycete Pleospora while others are speculated to be anamorphs of Leptosphaeria. Host Range: Most Alternaria species are common saprophytes that derive energy as a result of cellulytic activity and are found in a variety of habitats as ubiquitous agents of decay. Some species are plant pathogens that cause a range of economically important diseases like stem cancer, leaf blight or leaf spot on a large variety of crops. Latent infections can occur and result in post-harvest diseases or damping-off in case of infected seed. Useful Website: First report of leaf blight of Brachiaria brizantha in Brazil caused by Bipolaris cynodontisPLANT PATHOLOGY, Issue 6 2007D. M. Macedo No abstract is available for this article. [source] First report on leaf blight of Lindera obtusiloba caused by Pestalotiopsis microspora in KoreaPLANT PATHOLOGY, Issue 2 2007Y. H. Jeon No abstract is available for this article. [source] Evaluation of carrot resistance to alternaria leaf blight in controlled environmentsPLANT PATHOLOGY, Issue 1 2006A. Pawelec The objective of this study was to find a technique for plant resistance screening to alternaria leaf blight (ALB), caused by the fungus Alternaria dauci, in controlled environments. Glasshouse and laboratory screening methods were compared using three cultivars and F2 genotypes segregating for ALB resistance evaluated against self-pollinated F3 field-grown plants. Plant disease was assessed through a disease index obtained from the size and number of symptoms on carrot leaves. The results indicated the value of glasshouse evaluation and the inadequacy of detached leaf and hypocotyl assays for carrot screening for ALB resistance. Spearman's rank correlation, applied to results obtained with both F2 plants and their progeny, indicated that the optimal evaluation stage for ALB resistance in carrot is 20 days after inoculation. This test was powerful enough to be used as a prescreening test in breeding programmes. [source] First report of honeysuckle leaf blight (Insolibasidium deformans) on honeysuckle (Lonicera spp.) in the UKPLANT PATHOLOGY, Issue 4 2004P. A. Beales No abstract is available for this article. [source] Molecular analysis of the major Phytophthora species on cocoaPLANT PATHOLOGY, Issue 2 2004A. A. Appiah The internally transcribed spacer (ITS) regions of the ribosomal RNA (rRNA) gene cluster of 161 isolates of Phytophthora species involved in pod rot, stem canker and leaf blight of cocoa were analysed to determine inter- and intraspecific variation in this disease complex. The species P. palmivora, P. megakarya, P. capsici, P. citrophthora and P. nicotianae could all be clearly distinguished by PCR amplification of the ITS region followed by restriction analysis with HaeIII, HinfI, PvuII and AluI. This method provided a relatively rapid identification procedure for these species, and was able to distinguish isolates that had previously been misidentified by morphological methods. Sequence analysis showed that the four main cocoa-associated species formed two distinct groups, one comprising P. capsici and P. citrophthora, and the other P. palmivora and P. megakarya. Detailed sequence analysis and comparison with published literature suggested that P. capsici isolates from cocoa may be closely related to P. tropicalis, a species recently described from Cyclamen and Dianthus. [source] Bacterial leaf blight of strawberry (Fragaria (x) ananassa) caused by a pathovar of Xanthomonas arboricola, not similar to Xanthomonas fragariae Kennedy & King.PLANT PATHOLOGY, Issue 6 2001Description of the causal organism as Xanthomonas arboricola pv. fragariae (pv. nov., comb. nov.) A new bacterial disease of strawberry is described. This disease, called bacterial leaf blight of strawberry, is characterized by dry, brown necrotic leaf spots and large brown V-shaped lesions along the leaf margin, midrib and major veins. Symptoms are different from angular leaf spot of strawberry caused by the bacterium Xanthomonas fragariae. Strains of the bacterial leaf blight pathogen were characterized in a polyphasic approach by biochemical tests, fatty acid analysis, protein electrophoresis, serology, PCR, pigment analysis, ice-nucleation activity, AFLP analysis, DNA:DNA hybridization, pathogenicity and host range tests, and compared with a number of reference strains of X. fragariae and other Xanthomonas species. Bacterial leaf blight strains formed a homogeneous group in all tests, completely different from X. fragariae. They were the only strains causing leaf blight of strawberry upon artificial inoculation into strawberry. Fatty acid and protein electrophoretic analysis showed that the strains belong to the phenon X. campestris (sensu latu, including pathovars now classified as belonging to X. arboricola). AFLP analysis and DNA:DNA hybridization further clarified their taxonomic position as belonging to X. arboricola. The name X. arboricola pv. fragariae is proposed for the bacterium causing leaf blight of strawberry with strain PD2780 (LMG 19145) as pathovar type strain. Criteria for routine identification are given and the taxonomic status is discussed. [source] Suppression of southern corn leaf blight by a plant growth-promoting rhizobacterium Bacillus cereus C1LANNALS OF APPLIED BIOLOGY, Issue 1 2010Chien-Jui Huang Southern corn leaf blight (SCLB) is an important foliar disease of maize. In this study, an induced systemic resistance (ISR)-eliciting rhizobacterium Bacillus cereus C1L was used to protect maize against SCLB. Application of B. cereus C1L in maize rhizosphere effectively protected maize from SCLB under greenhouse and field conditions. The protection effect of B. cereus C1L was similar to that of Maneb (2 kg active ingredient per hectare), a recommended fungicide. Furthermore, possible factors of B. cereus C1L to elicit ISR and to promote plant growth were investigated. The results indicate that secreted factors and rhizosphere colonisation ability of B. cereus C1L are involved in ISR elicitation. In addition to biocontrol activity, B. cereus C1L was able to promote growth of maize in field. Compared with a non-treated control, leaf length, leaf width, plant height and fresh and dry weights of B. cereus C1L-treated corn plants significantly increased. Therefore, B. cereus C1L acts as a plant growth-promoting rhizobacterium of maize. [source]
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