Showing 11 results for Subject: General
Mehdi Sadravi,
Volume 1, Issue 1 (3-2012)
Abstract
Arbuscularfungi are root symbiontsof 80% of plants, such as most field crops and fruit trees. They establish in root tissue, arbuscule in endodermis cells, and an extramatrical fine hyphal net. These fungi byincreasing absorption of water and nutrient elements for plants, making changes in chemical constituents of plant tissues, competition with pathogens for nutrients and establishment site, structural changes in roots, alleviation of environmental stresses, and increasing population of useful bacteria in soil, help management of diseases caused by fungi, fungal like organisms, nematodes, bacteria, phytoplasmas and physiological disorders. Collection, identification, purification, propagation, and inoculation of these useful fungi to plants, can decrease usage of chemical fertilizers and pesticides that are harmful to consumers of agricultural products as well as to the environment
Saeid Tabein, Seyed Ali Akbar Behjatnia,
Volume 3, Issue 2 (9-2014)
Abstract
In addition to the full-length viral DNA genome, various types of smaller specific DNA molecules have been isolated from plants infected by DNA viruses. These DNAs are usually derived from viral genomes by different ways or have non-viral genome sequences. Some of these DNA have no significant effect on the virus cycle and on the incidence and progression of the disease, while some of them inducing the viral disease symptoms. These components that are known as satellite, defective and defective interfering DNAs, depend on helper viruses for replication, encapsidation and movement in plants. Satellites have no significant homology with the helper virus genome. However, they are required for inducing disease symptoms. While defective and defective interfering DNAs exhibit high homology with the genome of helper viruses, only defective interfering DNAs have ability to interfere with virus replication and with disease symptom induction and development. In this paper, the characteristics of these subviral DNAs and the possible mechanisms by which they are generated and transmitted in virus infected plants are discussed.
Keivan Karimi, Mahdi Arzanlou, Fariba Mirabi,
Volume 4, Issue 1 (3-2015)
Abstract
Karimi K., Arzanlou M. & Mirabi F. 2015. Barley scald disease. Plant Pathology Science 4(1):1-12.
Barley is one of the world`s most widely consumed cereal. Rhynchosporium commune, the causal agent of barley leaf scald, is one of the most deleterious pathogens of barley which can cause up to 40% yield loss, under favorable conditions. Primary infection takes place by spores produced on infected plant debris. The secondary infection can be repeated by spore dispersal by rain and wind. Although the teleomorphic stage is unknown, high levels of genetic diversity have been observed within and between populations of this pathogen, attributed to some mechanisms such as gene flow, parasexual cycle and asexual recombination. The management of this disease is mainly achieved through cultural and chemical measures of control and use of resistant cultivars. In this paper, different aspects of pathogen symptoms, taxonomy and biology of pathogen, and management of disease are discussed.
Amir Ramzani, Dr Safarali Mahdian,
Volume 5, Issue 1 (2-2016)
Abstract
Ramezani A. & Mahdian S. A. 2016. Biological control of post-harvest citrus diseases. Plant Pathology Science 5(1):14-25.
Post- harvest rot of citrus fruits is one of the most important limiting factors that reduce the life of harvested products and are one of the most important economical diseases in world’s citrus production areas. Two most important fungi that affect the citrus fruits, are green and blue molds which are produced by Penicillium digitatum and P. italicum, respectively. The disease are mainly managed by using the synthetic fungicides, but because of environmental hazards and appearance of resistant strains of the pathogen, the biological control by the use of bacterial, fungal and yeast antagonists can be suggested. The efficiency of yeasts such as Candida guilliermondii, C. saitoan, Pichia guilliermondi and Aureobasidium pullulans; the bacteria Pseudomonas fluorescens, Bacillus subtilis, Pantoea agglomerans and the fungus Muscodor albus, in controlling the green and blue molds of citrus is reported so far. In this paper, we tried to explain the method of biological control with emphasizing on the identification of useful microorganisms and their operation.
Yalda Vasebi, Saeid Buroon, Mohammad Mehdi Faghihi ,
Volume 6, Issue 2 (9-2017)
Abstract
Vasebi Y., Buroon S. and Faghihi M. M. 2017. Common pathogenic agents of plant and human. Plant Pathology Science 6(2):78-88.
Some plant pathogens are also serious threats to human health. Pathogenic fungi from the genera Alternaria, Aspergillus, Bipolaris, Cladosporium, Claviceps, Fusarium, Paecilomyces and Exserohilum, and some bacteriaa genera including Burkholderia, Enterobacter, Enterococcus, Escherichia, Erwinia, Pantoea, Pseudomonas, Salmonella, Serratia and Xanthomonas can cause harmful diseases in human. Diseases caused by these microorganisms in plants and human are described here and some researches to identify them on raw fruits and vegetables are suggested.
Maryam Mirtalebi, Reza Mostowfizadeh-Ghalamfarsa,
Volume 6, Issue 2 (9-2017)
Abstract
Mirtalebi M. & Mostowfizade-Ghalamfarsa R. Integrated management of gray mold disease. Plant Pathology Science 6(2):43-54.
Gray mold caused by Botrytis cinerea, is one of the most important postharvest diseases on fresh fruits and vegetables worldwide. The disease may start in the field and remain as a latent infection and then develop after harvest, during transportation, packaging, storage and marketing. Nowadays, application of fungicides is the main strategy to control the gray mold disease in conventional agriculture. The presence of fungicide residues in edible fruits and vegetables is a concern for consumers because pesticides are known to have potential harmful effects. Therefore, the search on finding the safe and effective disease control strategies has been accelerated. Integrated management of the disease by using some methods like optimal method of irrigation and fertilization, biological control, use of bioagents, disinfection of fresh fruits and vegetables after harvesting, storing and shipping in a cool and dry condition with low humidity and suitable ventilation are suggested.
Maryam Hatamabadi Farahani,
Volume 8, Issue 1 (3-2019)
Abstract
Hatamabadi-Farahani M. 2019. Root knot disease of pomegranate.
Plant Pathology Science 8(1):38-49. DOI:10.2982/PPS.8.1.38.
Pomegranate is an important fruit crop which is attacked by several pests and pathogens. Diseases caused by nematodes are of economic importance. The root knot nematodes (Meloidogyne spp.) causing considerable yield losses in pomegranate. Root knot nematodes are sedentary endoparasite that are basically parasites of the roots, produces knots on root which cause weak root function in the absorption and transfer of water and nutrient. Above ground symptoms include dwarfing the plants, yellowing and reduction of foliage, falling leaves and yield losses. Under favorable temperature and moisture, eggs are hatching and second stage pathogenic juveniles are released. The management strategies are including sanitation, construction of nursery in healthy areas, annual plowing of garden, drip irrigation, soil solarization, organic amendment of soil and strengthen the trees.
Mehdi Azadvar, Hamidreza Alizadeh, Mousa Najafinia, Mohammadreza Safarnejad, Samad Esfandiari,
Volume 8, Issue 2 (9-2019)
Abstract
Azadvar M, Alizadeh HR, Najafinia M, Safarnejad MR and Esfandiari S (2019) Citrus sudden decline disease in the south of Kerman province. Plant Pathology Science 8(2): 31-37. DOI: 10.2982/PPS.8.2.31
During recent years, the newly emerging disease, citrus sudden decline (CSD) has destroyed many of citrus trees grafted onto bael rootstock in the south of Kerman Province. The disease is caused by Candidatus Liberibacter asiaticus and its simultaneous infection to soil born pathogens or Ca. Phytoplasma aurantifolia, or heat and drought stresses can increase the disease severity and appearance of the decline symptoms. Using the healthy and certified rootstock, using the Sour Orange or Volkamer Lemon as rootstock, control of the sucking insects at the time of flushing, optimum irrigation with appropriate distribution especially during the summer season, control of soil born fungi and nematodes, avoiding stress to plant and appropriate pruning are recommended for prevention and management of CSD disease in the south of Kerman Province.
Samaneh Ahmadi, Fariba Ghaderi, Dariush Safaei,
Volume 9, Issue 1 (3-2020)
Abstract
Ahmadi S, Ghaderi F, Safaee D (2020) Oak charcoal rot disease in Iran. Plant Pathology Science 9(1):118-128. DOI: 10.2982/PPS.9.1.118.
Oak charcoal rot is caused by two fungi, Biscogniauxia mediterranea and Obolarina persica. These fungi, which are opportunistic or secondary invaders and attack stressful trees, are one of the main problems of oak forests in Iran. The disease was first reported in 2011 in the northern forests on Quercus castaneifolia and Zelkova carpinifolia trees and then in the Zagros forests on Q. brantii tree. The disease has spread rapidly in the forests of the Zagros over the years. Symptoms of the disease include decay and death of trees, browning of leaves and early fall. Gum secretion on the branches and trunks of old trees and browning of wood texture and woody vessels can be seen up and down the height of the trunk. The morphological characteristics of pathogens, the spread and survival of pathogens, and disease management methods are described in this article.
Marzieh Mehrabioun Mohammadi, Narges Ahmadi, Mahdi Arzanlou,
Volume 9, Issue 1 (3-2020)
Abstract
Mehrabioun Mohammadi M, Ahmadi N, Arzanlou M (2020) Dutch elm disease. Plant Pathology Science 9(1):91-100. DOI: 10.2982/PPS.9.1.91.
Elm trees are one of the most important ornamental trees and are widely used in the design of urban green spaces. Dutch elm disease is recognized as one of the most important elm diseases in the world. The disease has become an epidemic worldwide and at least three species of Ophiostoma including O. ulmi, O. novo-ulmi and O. Himal-ulmi that differ in geographical distribution and invasion power, are involved in this disease. In Iran, O. ulmi and O. novo-ulmi are known to involve in this disease, with O. novo-ulmi being more virulent. Management of the disease is mainly achieved through preventive and quarantine methods, health measures, resistant cultivars and the use of chemical compounds. Various aspects of the disease, including disease symptoms and signs, pathogen biology and ecology, disease management methods are reviewed in this paper.
Aminallah Tahmasebi, Mohamad Hamed Ghodoum Parizipour,
Volume 9, Issue 1 (3-2020)
Abstract
Tahmasebi A, GhodoumParizipour MH (2020) The role of brassinosteroid hormones in plant response to pathogens. Plant Pathology Science 9(1):108-117. DOI: 10.2982/PPS.9.1.108.
Plants are usually attacked by several pathogens. Different defense pathways in plants have evolved in reaction to pathogens. Plant defense responses have been shown to be regulated by various plant hormones. Brassinosteroids are plant-specific steroid hormones that play important roles in regulating growth and developmental processes. In addition to acting as a regulator of plant growth, they also play a role in defense responses to pathogens. Many researches have been done on their role in plant resistance to fungi, bacteria and viruses, which are described in this article. Further understanding of the role of these hormones in plant defense responses can be useful in inducing resistance or producing plants resistant to pathogens.
