Showing 3 results for Chitosan
Vahid Ghazi-Mohseni, Seyed Kazem Sabbagh, Sedigheh Esmaili Bahabadi,
Volume 4, Issue 1 (3-2015)
Abstract
Ghazi-Mohseni V., Sabbagh S. K. & Esmaili Bahabadi S. 2015. Application of chitosan in plant diseases management. Plant Pathology Science 4(1):54-63.
Chitosan is a biodegradable natural compound derived from the bark of crabs and shrimp which have antimicrobial role against fungi and bacteria. Chitosan has directly effects on morphology of treated pathogens which reflect its fungistatical and fungicidal activity. It has been shown that chitosan increases production of glucanohydrolase, phenolic compounds and specific phytoalexin synthesis with antifungal activity and reduces enzymes such as polygalacturonase, pectin methyl-esterase that related to soft rot . In addition, chitosan can develop structural barriers via lignin synthesis. Therefore chitosan is considered as a new non-toxic biological material, inducer resistance of plants against diseases.
Aida Ahmadizadeh Esfahani, Mehdi Sadravi, Sholeh Kazemi,
Volume 8, Issue 2 (9-2019)
Abstract
Ahmadizadeh Esfahani A, Sadravi M and Kazem S (2019) Effect of nano-chitosan on early blight disease of tomato. Plant Pathology Science 8(2):102-109.
DOI: 10.2982/PPS.8.2.102.
Introduction: Early blight caused by Alternaria species is one of the most important tomato diseases in the world. The disease has been reported from most areas in Iran with up to 90% infection. This study was conducted to investigate the effect of nano-chitosan on the severity of the disease and its use as a replacement of the chemical fungicide, chlorothalonil. Materials and Methods: Diseased tomato plants of fields and greenhouses of Fars province in southern Iran were sampled. Pathogens were isolated from diseased tissues, purified and identified by studying their morphological characteristics. The effect of nano-chitosan at three concentrations of three, five and seven grams per liter and the fungicide chlorothalonil were tested before and after inoculation of two pathogens. The disease severity indexes were measures in Sunseed and 16 cultivars of tomato under greenhouse conditions using a factorial experimental in completely randomized design with four replications. The data were analyzed with comparing the means. Results: The isolated pathogens were identified as A. solani and A. alternata. Results of the greenhouse experiment showed that A. solani was more aggressive than A. alternata and the cultivar 16 was more resistant to the disease. Nano-chitosan at 5 and 7 mg/ l significantly reduced disease severity indexes when use before pathogen inoculation, and at 7 mg/l when use after pathogen inoculation. Conclusion: Nano-chitosan can be used as a bio-fungicide to replace chlorothalonil as a chemical fungicide for disease management.
Safarali Mahdian, Amir Ramzani Domirkolaei, Mohammadali Tajik Ghanbari,
Volume 11, Issue 1 (3-2022)
Abstract
Mahdian S, Ramzani Domirkolaei A, Tajik Ghanbari M (2022) Effect of myrtle essential oil, chitosan and thiabendazole fungicide on citrus green mold. Plant Pathology Science 11(1):74-88. Doi: 10.2982/PPS.11.1.74.
Introduction: Green mold (Penicillium digitatum) is one of the most important post-harvest pathogens of citrus fruits. Tens of thousands of citrus fruits are often destroyed by green mold in Iran every year. The use of chemical toxins to control the disease, in addition to negative environmental effects, leads to the selection of fungal-resistant populations and also endangers consumer health, so non-chemical control of the pathogen has become an important goal of researchers in recent years. Materials and Methods: The essential oil components of myrtle (Myrtus communis L.) were extracted with a Clevenger apparatus and their compounds were identified with a gas chromatography apparatus with a mass spectrometer. The inhibitory effect of myrtle essential oil and the fungicides chitosan and thiabendazole on spore germination and colony growth was investigated by mixing with PDA and PDB under laboratory conditions and by impregnating the fruit surface during storage. Results: Thirteen compounds were identified in myrtle essential oil, which was quantitatively the highest compound 1-8 cineole. Myrtle essential oil at a concentration of 1700 ppm and chitosan at a concentration of 500 ppm inhibited 100% of fungal colony growth, as did the fungicide thiabendazole. Conclusion: It is possible to use myrtle essential oil or chitosan as an alternative to the fungicide thiabendazole to control citrus green mold.
