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91.
Effects of defoliation caused by the processionary moth on growth of Crimean pines in western Turkey
Serdar Carus 《Phytoparasitica》2009,37(2):105-114
An outbreak of the pine processionary moth (PPM), Thaumetopoea wilkinsoni Tams (Lepidoptera: Thaumetopoeidae), began in spring 1998 and lasted 6 years in a Crimean pine (Pinus nigra Arnold) plantation in western Turkey. The effects of PPM on the radial, height and volume growth of Crimean pine trees were
investigated by examining the increment losses for three defoliation intensities (groups). PPM activity in Crimean pine stand
was assessed through radial increment analysis of cores extracted at breast height. In 2004, increment cores were collected
from moderate and high defoliation and low defoliation dominant or co-dominant trees. Based on the sample, annual radial growth
indices from 1998 to 2004 were calculated. Growth functions were defined as the cumulative sum of radial, height and volume
increment graphically compared between Crimean pine defoliation group sample trees. The sample trees are the same subspecies
and varieties. After the defoliations, radial, height and volume growth of low defoliation group trees was found to be significantly
greater than that of the other affected groups. During the 1998–2004 period the total radial growth of low, moderately affected
and highly affected trees was, respectively, 49, 33 and 31 mm; the total height growth was 3.1, 1.8 and 1.0 m; and the total
volume growth was 50, 14 and 10 dm3. 相似文献
92.
Sobhi M. Girgis Frederic P. Bem Chrysostomos I. Dovas Athanassios Sclavounos Apostolos D. Avgelis Mina Tsagris Nikos Katis Panayota E. Kyriakopoulou 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(2):203-211
Unusual symptoms were observed on ‘Baresana’ x ‘Baresana’ Vitis vinifera hybrid vines in the Grapevine Variety Collection of the Grapevine Institute, Athens. The affected vines showed sharp angular
mosaic on leaves, along the veins and in vein angles, malformations, abortive flowers or very few berries with smaller, wrinkled
and non-germinating seeds, as well as gradual decline, severe stunting and death of the vine. Serological tests on diseased
vines for the presence of 13 known grapevine viruses gave negative results. An infectious agent was transmitted mechanically
to several herbaceous indicator plants. Koch’s Postulates were fulfilled, and the agent, proven to be a virus, was named Grapevine angular mosaic virus (GAMV). Serological tests have been developed for the virus. The most conserved polymerase region showed significant similarity
of GAMV with members of subgroup 1 of the Ilarvirus genus; however ML phylogenetic analysis could not support its clustering within this subgroup. GAMV differs serologically
and in particle morphology from Grapevine line pattern virus (GLPV) a putative member of the Ilarvirus genus that infects grapevine. It is proposed that GAMV is a novel member of the Ilarvirus genus. 相似文献
93.
M. Kvas E. T. Steenkamp A. O. Al Adawi M. L. Deadman A. A. Al Jahwari W. F. O. Marasas B. D. Wingfield R. C. Ploetz M. J. Wingfield 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(2):195-199
Mango malformation, caused by Fusarium mangiferae, represents the most important floral disease of mango. The first symptoms of this disease were noticed in the beginning of
2005 in plantations at Sohar in the Sultanate of Oman. The affected inflorescences were abnormally enlarged and branched with
heavy and dried-out panicles. Based on morphology and DNA-sequence data for the genes encoding translation elongation factor
1α and β-tubulin, the pathogen associated with these symptoms was identified as F. mangiferae. 相似文献
94.
Fangjing Li Gaoqing Yuan Ting Liao Qiqin Li Wei Lin 《Journal of General Plant Pathology》2017,83(4):264-267
In 2014 and 2015, an unknown leaf spot disease was found on tobacco in Guangxi, China. The fungus isolated from these spots was identified as Fusarium proliferatum based on morphological characteristics and sequence analysis of translation elongation factor 1 alpha (tef1α). This fungus also reproduced leaf spot symptoms after inoculation and was reisolated from the symptomatic lesions. This is the first report of a new leaf spot caused by Fusarium proliferatum on tobacco. 相似文献
95.
Keiko Hayashi Fumihiko Suzuki Yuriko Hayano-Saito 《Journal of General Plant Pathology》2017,83(5):304-309
For sustainable control of rice blast with fungicides, efficient monitoring of the emergence and spread of fungicide-resistant isolates is needed. We developed simple and reliable PCR-based DNA markers to detect isolates resistant to melanin biosynthesis inhibitor targeting scytalone dehydratase (MBI-D) and quinone outside inhibitor (QoI) fungicides. Through the use of DNA templates prepared from mycelia on filter paper or from infected leaves, these markers enable rapid (a few hours) genotyping of point mutations that confer resistance. The developed multiplex marker detected resistance to both MBI-D and QoI in a single PCR and further reduced the time needed for diagnosis. 相似文献
96.
Juha Kaitera Ritva Hiltunen Tuomas Kauppila Jarkko Hantula 《European journal of plant pathology / European Foundation for Plant Pathology》2017,148(2):367-377
Fusarium is one of the most destructive fungal genera whose members cause many diseases on plants, animals, and humans. Moreover, many Fusarium species secrete mycotoxins (e.g. trichothecenes and fumonisins) that are toxic to humans and animals. Fusarium isolates from date palm trees showing disease symptoms, e.g. chlorosis, necrosis and whitening, were collected from seven regions across Saudi Arabia. After single-sporing, the fungal strains were morphologically characterized. To confirm the identity of morphologically characterized Fusarium strains, three nuclear loci, two partial genes of translation elongation factor 1 α (tef1α) and β-tubulin (tub2), and the rDNA-ITS region, were amplified and sequenced. Of the 70 Fusarium strains, 70 % were identified as F. proliferatum that were recovered from six regions across Saudi Arabia. Fusarium solani (13 %), as well as one strain each of the following species: F. brachygibbosum, F. oxysporum, and F. verticillioides were also recovered. In addition, five Fusarium-like strains were recognized as Sarocladium kiliense by DNA-based data. The preliminary in vitro pathogenicity results showed that F. proliferatum had the highest colonization abilities on date palm leaflets, followed by F. solani. Although F. oxysporum f. sp. albedinis is the most serious date palm pathogen, F. proliferatum and F. solani are becoming serious pathogens and efforts should be made to restrict and control them. In addition, the potential toxin risks of strains belonging to F. proliferatum should be evaluated. 相似文献
97.
Geleta Dugassa Barka Eveline Teixeira Caixeta Robson Ferreira de Almeida Samuel Mazzinghy Alvarenga Laércio Zambolim 《European journal of plant pathology / European Foundation for Plant Pathology》2017,149(3):543-561
Countering the economic hurdle caused by coffee leaf rust disease is most appealing at this time as it has posed a major threat to coffee production around the world. Establishing differential expression profiles at different times following pathogen invasion in both innate and acquired immunities unlocks the molecular components of resistance and susceptibility. Suppression subtractive hybridization (SSH) was used to identify genes differentially over-expressed and repressed during incompatible and compatible interactions between Coffea arabica and Hemileia vastatrix. From 433 clones of expressed sequence tags (ESTs) sequenced, 352 were annotated and categorized of which the proportion of genes expressed during compatible interaction were relatively smaller. The result showed upregulation and downregulation of various genes at 12 and 24 h after pathogen inoculation in both interactions. The use of four different databases in searching for gene homology resulted in different number of similar sequences. BLASTx against EMBL-EBI (European Molecular Biology Laboratory-European Bioinformatics Institute) database being with the maximum (100%) hits for all the annotated sequences. RT-qPCR analysis of seven resistance-signaling genes showed similar expression patterns for most of the genes in both interactions, indicating these genes are involved in basal (non-specific) defense during which immune reactions are similar. Using SSH, we identified different types of resistance related genes that could be used for further studies towards resistant cultivar development. The potential role of some of the resistance related proteins found were also discussed. 相似文献
98.
The review describes the history of pheromone research in Israel in 1975–2015. The research focused on sex pheromones of moths that were important agricultural pests. Identification, synthesis and field application of sex pheromones was performed. Synthetic procedures of several known sex pheromones were developed. Monitoring and control of key pest moths was evaluated. The interactions of pheromone components of closely related species were studied in field and laboratory experiments. The sex pheromones of three scale insects, two mealybug species and Matsucoccus josephi were studied. New syntheses were developed and the pheromones were implemented in pest management. Structure activity relationship of the pheromonal and kairomonal of the M. josephi pheromone was investigated. Different pherotypes of P. ficus were identified and evaluated. The aggregation pheromone of sap beetles in combination with food baits was evaluated. The aggregation pheromone of the almond bark beetle was identified and a stereospecific synthesis of its enantiomers was developed. Monitoring the pest in stone fruit orchards was implemented. The activity of the pheromone biosynthesis activating neuropeptide (PBAN) was studied in Helicoverpa armigera and Heliothis peltigera. The ligation technique was used to assess the effect of PBAN on the production of female and male pheromones. A structure-activity relationship study of PBAN indicated that shorter peptides display activity as the full length PBAN. A series of linear and cyclic peptide analogs was prepared, resulting in the discovery of a lead antagonist. The research and development activity facilitated the intensive integration of pheromones in the pest management regimes in Israeli agriculture. 相似文献
99.
Jalal Soltani Ali A. Aliabadi 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(1):65-70
Bacterial blight disease of Persian walnut (Juglans regia, L.), caused by Xanthomonas arboricola pv. juglandis (Xaj), leads to significant nut losses in northern, central and western areas of Iran. To identify the natural sources of resistance
to disease in the endemic walnut genotypes of Iran, sixteen walnut genotypes, collected from different areas of Hamedan province,
were inoculated with Xaj in a randomized complete block design with five replicates for each genotype. Two-year old genotypes were gently sprayed
with a suspension of bacteria adjusted to approximately 2 × 109 cfu ml−1 of distilled water in May. Infected leaves were rated for disease 28 and 42 days after inoculation, using a 0 to 5 severity
scale, based on the number, size and distribution of lesions on the leaves. Data analyses showed that there were variations
among genotypes in response to pathogen. Upon inoculation by bacterial suspension genotype 94 showed the highest resistance
to both disease incidence and its progress after 4–6 weeks of infection. Genotype 65 showed high susceptibility to disease
and genotype 69 showed high susceptibilities both to disease incidence and its progress after 4–6 weeks of infection. 相似文献
100.
Ting-Fang Hsieh Hung-Chang Huang R. Scott Erickson 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(4):579-584
Studies were conducted in the laboratory and greenhouse to determine the distribution of Erwinia rhapontici in plants arising from naturally infected seeds of pea or artificially inoculated seeds of bean and wheat, and whether the
pathogen is transmitted to the subsequent generation of seeds. Infected seeds were planted in pots of Cornell mix in the greenhouse,
and sampled at specified intervals throughout the plant growth cycle (seedling stage, elongation stage, flowering stage, seed
formation stage, and maturity). Plating of surface sterilized lateral roots, tap roots, basal stems, mid-stems, apical stems,
petioles, pods, and seeds of pea and bean, and of lateral roots, sub-crown internodes, basal stems, mid-stems, apical stems,
peduncles, glumes, and seeds of wheat revealed that the bacterial pathogen spread from infected seeds to the lower parts of
the plant tissues, but failed to spread further to the seeds produced on these plants. The study concludes that E. rhapontici did not establish systemic infection throughout the plants. Possible mechanisms of infection of seeds are discussed. 相似文献