Plant Pathology Science

Methods for Management of Citrus Blast Disease

MORTEZA GOLMOHAMMADI

Golmohammadi, M. & Banihashemian S. N. 2017. Management method of citrus blast disease. Plant Pathology Science 6(2):1-13.

Citrus bacterial blast is reported from many parts of citrus growing areas of world. It is one of the most important diseases of citrus in north of Iran, but its damage is different because of year-to-year climate variability. The disease is caused by two species of Pseudomonas. In those years that air humidity and temperature are suitable, these bacterial species can cause serious damage to citrus trees. The main symptom of citrus blast disease is wilting and dieback of branches. Some practices for management of this disease are illustrated in this article.

Four Important Oak Diseases in Iran

mehdi sadravi

Sadravi M. & Moradi N. 2017. Four important oak trees diseases in Iran. Plant Pathology Science 6(2):14-23.

Zagros Mountains in the west of Iran and some areas in the north of Iran are covered by oak trees. Four important diseases of Iranian oak trees are charcoal rot, chestnut blight, sudden death and powdery mildew. The symptoms of these diseases and the characteristics of pathogens as well as their prevalence are described in this article. Some strategies for protecting the oak trees from these diseases are also proposed here.

Plants Defense Mechanisms Against Pathogens

Jalal Gholamnezhad

Gholamnejad J. 2017. Plants defense mechanisms against pathogens. Plant Pathology Science 6(2):24-32.

Plants have many defense mechanisms against pathogens that can be stimulated and activated by some microorganisms or chemicals. There are five types of induced resistance in plants that are included: localized acquired resistance, systemic acquired resistance, systemic gene silencing, induced systemic resistance, and systemic wounding response. Systemic acquired resistance is the most important type of induced resistance in plants that result in continuous and prolonged protection from infection against a wide range of pathogens. Formation of pathogenesis related proteins, alteration of cell wall with sedimentation and binding of polysaccharides, proteins, glycol-proteins, phenols, phytotoxins, and ligninification are the stages of occurrence of this type of resistance in plants.

A Review on the Application of Benzothiadiazole in Plant Diseases Management

Zabihollah Azami-Sardooei

Azami-Sardouei Z., Fekrat F. and Ghalavand F. 2017. A review on the application of benzothiadiazole in plant diseases management. Plant Pathology Science 6(2):33-42.

The use of plant defense activators is a novel method of plant diseases management in recent years. Benzothiadiazole (BTH), is the first synthetic plant defense activator. In general, Benzothiadiazole has no direct effect against the pathogens, but it can activate the systemic acquired resistance (SAR) in plants, against a number of plant diseases. In addition, BTH widely is used to protect the plants against a range of pathogens on wheat, tomato, bean, tobacco, lettuce, banana and pears. In overall, Benzothiadiazole can be used as a safe and reliable product for plant protection and also as an alternative for chemical pesticides, which they have hazardous effects on environment.

Integrated Management of Gray Mold Disease

Reza Mostowfizadeh-Ghalamfarsa

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.

Biological Control of Rhizoctonia Damping-off Disease

Samaneh Samavat

Biological control of Rhizoctonia damping-off disease. Plant Pathology Science 6(2):55-67.

Damping-off caused by Rhizoctonia solani J. G. Kühn is a very important plant disease among soil-borne diseases that make severe damages on a wide range of plants in the world. Biological control of this disease with Trichoderma, Gliocladium, Bacillus, Pseudomonas and Rhizobium species has been reported as a successful management method. The results of some researches on this area and the mechanisms of the effect of these antagonistic fungi and bacteria are described here.

Application of Nanomaterials in Management of Fungal Plant Diseases

Mahdi Davari

Hoseinzadeh A., Davari M. and Habibi-Yangjeh A. 2017. Applications of nanomaterials in the fungal plant diseases management. Plant Pathology Science 6(2):68-77.

The use of nanotechnology in plant disease management has been seriously considered by researchers in recent years. Some of these reteaches have shown the antifungal effects of nano zinc oxide on Botrytis cinerea and Penicillium expansum; nano copper oxide on Aspergillus flavus; silver nanocomposite compounds (SiO₂/Ag₂S) on Aspergillus niger; Fe₃O₄/ZnO/AgBr on Fusarium graminearum, F. oxysporum and Botrytis cinerea, and carbon nanomaterials on F. graminearum. Their antifungal mechanisms are including: degradation of lipid and protein, damage to cell membranes, water channels blocking by nanomaterials and loss of spore water and plasmolysis and the inhibition of growth or destruction of fungal hyphae and prevent the sporulation.

Common Pathogens of Plant and Human

yalda vasebi

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.

Hyrcanian Boxwood Blight Disease

Samaneh Samavat

Samavat S. 2017. Hyrcanian boxwood blight disease. Plant Pathology Science 6(2): 89-96.

Hyrcanian boxwood which is one of the evergreen shrubs is native of northern forests of Iran. Blight disease caused by Calonectria pseudonaviculata is one of the most important diseases of this plant, which causes severe leaf loss and decline in susceptible cultivars. This disease has been reported from the forests of Gilan and Mazandaran provinces. The history and importance of the disease, geographical distribution, disease symptoms, pathogen characteristics, the disease cycle, and the methods for disease prevention as well as the mechanical and chemical control measures are described.

Fungi Parasitic Viruses

Nazerian

Nazerian E. and Sayad S. 2017. Fungi parasitic viruses. Plant Pathology Science 6(2):97-104.

Several viruses have been identified as parasites of some fungal isolates that cause chestnut blight, canola stem rot, wheat head blight, corn smut, and a number of molds and yeasts. These mycoviruses reduce growth, proliferation and pathogenicity and cause abnormal pigmentation in the mycelium, or mutations in the host fungus. These viruses can be transmitted to other isolates of the same fungus or other fungi by hyphen anastamosis. Therefore, identification of hypovirulent and infected isolates of pathogenic fungi to viruses and their use for plant protection against highly pathogenic isolates and plant diseases management is recommended.