Showing 3 results for RAHJOO
Vahid Rahjoo , Majid Zamani ,
Volume 1, Issue 2 (9-2012)
Abstract
Fusarium ear rot is one of the most important diseases of corn in Iran. This disease cause by Fusarium moniliforme fungus. Its symptoms are pink to red spots on ear, cause it completely rot and eventually loss of yield quantity and quality. Identification and cultivation resistant or semi-resistant corn hybrids is the best management method of this disease. Artificial infection of maize hybrids with fungal suspension of causal agent is an affective method to study their reactions, determine base on disease severity index (%DS). According to research conducted in Iran, between 12 planting hybrids, 2 hybrids K3493 / 1 × K18 and KLM 77029/8-1-2-3-2-3 × MO17 are resistant, and 9 are semi- resistant . With extension, cultivation of these hybrids, can manage the disease and increase the quality and quantity of maize hoped.
Masoumeh Hatamzadeh , Vahid Rahjoo ,
Volume 2, Issue 2 (9-2013)
Abstract
Powdery mildew is one of the most important diseases of alfalfa crops in Iran. Leveillula taurica which is the main causal pathogen on alfalfa, has a wide host range and distributed in warm and arid areas of the world. Planting the resistant and moderately resistant cultivars is the most appropriate method to control the powdery mildew of alfalfa. Based on field trials in Iran, the cultivars Codi and Gharehyonjeh are moderately resistant Bami is moderately susceptible Hamedani 121 and Hamedani 122 are susceptible and Mohajeran, Simertchenskaya, Diablorde and Ranger are highly susceptible to this disease. Accordingly, Codi and Gharehyonjeh which are the moderately resistant cultivars can be used for management of this disease.
Vahid Rahjoo , Masoumeh Hatamzadeh, Hatamzadeh Mahrokh, Sayyed Mohammad Ali Mofidian,
Volume 3, Issue 1 (3-2014)
Abstract
Alfalfa downy mildew caused by Peronospora trifoliorum de Bary, is one of the factors decreases alfalfa yield. It distributes as epidemic and causes falling and yellowing the leaves in favorite conditions especially in spring and first cutting of alfalfa. In order to select alfalfa resistant ecotypes to downy mildew disease, standard greenhouse and field experiments can be used. In greenhouse tests 7-day-old seedlings are inoculated with spore suspension and after incubation period, the percentage of the symptomless seedlings is compared with resistant control as soon as disease symptoms appear. Field experiments are carried out with minimum three replications of alfalfa ecotypes in an appropriate statistical design at some locations in which natural condition for disease occurrence exists. A susceptible ecotype is used as spreader in order to help disease distribution. Resistance of ecotypes is evaluated based on percentage of the leaves infection in five different classes (1-5) scoring system. Nowadays large number of researches has been done on alfalfa resistance to downy mildew and several resistant cultivars have been reported worldwide. For example KS224 and Saranac have been known as resistant cultivars to downy mildew. Some cultivars and ecotypes such as Kiseverdai, Nikshahri, Gharghlooogh and Malek-Kandi show good tolerance to disease in a few researches carried out in Iran. Results of field and greenhouse experiments are relative similar and show good correlation. It seems that using these ecotypes in different regions of Iran especially cold regions in which disease is frequently observed and considering other management methods such as appropriate cutting can be considerably decrease the occurrence of the disease and the crop loss.
