Showing 5 results for Pythium
Zahra Irsoleimaniand, Reza Mostowfizadeh-Ghalamfarsa,
Volume 1, Issue 1 (3-2012)
Abstract
The importance of plant protection in modern agriculture increases as crop yields and concerns about production quality rise. Plant protection should be sufficiently effective, affordable and considerate of the environment. The integration of biological and chemical control has a potential for success because of a possible synergistic effects. It is necessary to look for organisms suitable for use in biological control, and in order to study the mechanisms of their action and the optimal conditions for incorporating such agents in plant protection and integrated management systems. One of such microorganisms is PythiumoligandrumDrechslerthatbelongs to the phylumOomycetes. This soil-resident saprophytic microorganism can be parasitic and hyperparasitic on many fungi within the same or other classes. The antagonistic activity of P. oligandrumis a multifaceted process which depends on the target species involved. P. oligandrumis nonpathogenic on 12 species of crops that belong to six families. It occurs on the root surface together with plant pathogenic fungi, predominantly in the regions of hypocotyl – taproot without penetrating the plant tissues. The plant growth is reportedly stimulated by this species. P. oligandrum can be utilized for biological control on a wide spectrum of crop plants. Different methods of application have been developed. The most effective activity of this microorganism is the mycelial growth inhibition of the plant pathogenic fungi.
Mahya Rahimizadeh, Mehdi Sadravi,
Volume 6, Issue 1 (2-2017)
Abstract
Rahimizadeh M. & Sadravi M. 2016. Eight useful Aspergillus species. Plant Pathology Science 6(1): 22-32.
Aspergillus species are saprophytic fungi which can live on plant debris in the soil and water and also on some plant products, stored fruits and grains. They can be identified by studying the features of colonies, conidiophores, vesicles, phialids and conidia, on selective culture media. The biocontrol potential of some isolates of A. flavus, A. fumigatus, A. niger, A. piperis, A. repens, A. tamarii, A. terrus and A. tubingensis, against some plant diseases such as cocoa black pod, root galls and Fusarium root rot of tomato, Alternaria leaf spot, Fusarium dry rot, potato pink and soft rot of tubers has been proven. They also can act as plant growth promoter and aflatoxin reducer agent in seeds and nuts. Key morphological characteristics of these eight species of Aspergillus is described in this paper. Most of these species are reported from Iran, thus identification and application of their efficient isolates can be suggested in plant diseases management as well as the plant growth enhancement programs.
Fariba Ghaderi,
Volume 8, Issue 2 (9-2019)
Abstract
Ghaderi F (2019) Incidence of root and crown rot disease of black cumin in the southwest of Iran. Plant Pathology Science 8(2):1-8. DOI: 10.2982/PPS.8.2.1
Introduction: Black cumin, an annual flowering plant in the family Ranunculaceae, is a medicinal herb with many pharmacological properties. Crown and root rot disease of this plant has been reported in most countries worldwide. This study was conducted to investigate the occurrence of this disease and identifying the causal agent in southwest of Iran. Materials and Methods: Black cumin farms were visited in Kohgiluyeh and Boyer-Ahmad province and southwest of Iran. Plants with crown and root rot were sampled. Pieces of infected root and crown were washed with tap water, dry blotted and plated on CMA-PARP. In total, 17 isolates of two different fungus-like species were isolated from rotted root and crown. Species identification was done based on morphological characteristics and temperature requirement. Pathogenicity test of the isolates were done on 3-week-old seedlings of Baft cultivar under greenhouse condition. Results: Eleven isolates were identified as Pythium aphanidermatum and six isolates as Phytophthora drechsleri. Both of these fungus-like species were pathogenic on the tested black cumin variety. Conclusion: Crown and root rot disease is present in the farms of black cumin in the southwest of Iran. The causal agents of this disease were identified as Pythium aphanidermatum and Phytophthora drechsleri. The black cumin cultivar Baft is susceptible to these pathogens.
Mrs. Mahsa Samiee, Mahdi Davari,
Volume 9, Issue 2 (8-2020)
Abstract
Samiee M, Davari M (2020) Important diseases of turf in Iran. Plant Pathology Science 9(2):119-128. DOI: 10.2982/PPS.9.2.119.
Turf grass is the most important grown plant in urban green space, which functions such as temperature adjustment, increase in relative humidity, air softness and dust absorption. Fungal and fungal-like diseases are the most common lawn diseases in Iran, affecting this plant at all stages of growth, causing its decline. Pythium, Fusarium, Microdochium, Rhizoctonia, Bipolaris, Pyricularia and Colletotrichum species are known as damping-off, root and crown rot, leaf spot and anthracnose pathogens of lawns in Iran. The symptoms of these diseases, the morphological characteristics of pathogens and the methods for their management are described.
Masoumeh Delaramifar, Mahdi Pirnia, Mojtaba Keykhasaber, Shirahmad Sarani, Hamideh Khajeh,
Volume 12, Issue 2 (9-2023)
Abstract
Introduction: Damping-off caused by Pythium aphanidermatum is one of the major diseases of luffa. Identifying and planting of resistant varieties is an environmentally friendly solution for integrated disease management. This study was conducted to determine the reaction of eight native and non-native luffa genotypes to the disease. Materials and Methods: The pathogen (Pythium aphanidermatum IRAN597C) was obtained from the collection of fungi of the Iranian Institute of Plant Protection Researches. It was inoculated into seedlings of eight luffa genotypes. After the appearance of yellowing symptoms and seedling death, the disease index (DI) and the area under the disease progression curve (AUDPC) were calculated for each genotype. Koch's postulates were carried out to prove pathogenicity and the pathogen was isolated from diseased seedlings. Then, for molecular confirmation of the pathogen, ITS-rDNA sequencing was used. Results: The sequencing of the ITS-rDNA region of the pathogen showed a phylogenetic affinity of 99% with other isolates of P. aphanidermatum. According to the DI, the northern large and the long luffa genotypes were grouped as sensitive genotypes, and other genotypes including northern black seed, northern white seed, toori, Afghani, grooved and Brazilian were grouped as resistant genotypes. Based on the AUDPC, the northern black seed, and northern white seed genotypes showed the lowest level, toori, grooved, Afghani and Brazilian genotypes showed the medium level, and northern large and long luffa genotypes showed the highest AUDPC level. Conclusion: Considering the low values of the DI and AUDPC in the northern black seed and northern white seed genotypes, planting these two genotypes is suggested for management of the disease in luffa.
