תפריט נגישות
ניגודיות עדינהניגודיות גבוהה
מונוכרום
הדגשת קישורים
חסימת אנימציה
פונט קריא
סגור
איפוס הגדרות נגישות
להורדת מודול נגישות חינם תפריט נגישותניגודיות עדינהניגודיות גבוההמונוכרוםהדגשת קישוריםחסימת אנימציהפונט קריאסגוראיפוס הגדרות נגישותלהורדת מודול נגישות חינםTomato powdery mildew (Oidium neolycopersicum) has started to cause severe epidemics on tomato about 15 years ago. it mainly infects Solanaceae and Curcubitaceae plants. The symptoms on tomato plant include powdery white lesions on the upper side of leaves and on all other aerial plant parts except for on the fruits. In severe outbreaks, the lesions coalesce and the disease is debilitating resulting in fast death of leaves. It is extremely common in greenhouse tomatoes world-wide but increasing in importance on field-grown tomato crops. Suppression of the pathogen relies mainly on chemical fungicides. The fast nature of epidemic development results in many and frequent sprays. Our objectives were to study the disease biology and to find new friendly means of control of the disease including biocontrol agents in order to later structure an integrated control system that will result in reduction of chemical fungicides use and residues. O. neolycopersici conidia germination was highest at temperature 25ºC, high relative humidity (RH) and low light intensity, whereas, conidia production is higher at 22°C, lower RH and higher light intensity (but fluctuating greenhouse temp result in higher number of conidia). Under field conditions, epidemics developed faster under conditions of high RH and moderate temperature. Accordingly, we simulated conditions for significant epidemic development on potted tomato plants subjected to artificial inoculation in experimental greenhouses. While testing various yeast and bacterium isolates ,it was found that few of them reduced disease severity by up to 80% on potted plants under heavy disease pressure. However, disease suppression was better on upper leaves than on lower leaves. Disease severity was significantly higher on the lower leaves, thus control efficacy may be negatively related to the disease pressure and the time the plant organ was exposed to the pathogen inoculum and the biocontrol agent. The potential biocontrol agents did not affect the germination and germ tube elongation of the Oidium conidia. However, three of the micro-organisms reduced conidia formation on the thallus of O. neolycopersici on leaves.
Tomato powdery mildew (Oidium neolycopersicum) has started to cause severe epidemics on tomato about 15 years ago. it mainly infects Solanaceae and Curcubitaceae plants. The symptoms on tomato plant include powdery white lesions on the upper side of leaves and on all other aerial plant parts except for on the fruits. In severe outbreaks, the lesions coalesce and the disease is debilitating resulting in fast death of leaves. It is extremely common in greenhouse tomatoes world-wide but increasing in importance on field-grown tomato crops. Suppression of the pathogen relies mainly on chemical fungicides. The fast nature of epidemic development results in many and frequent sprays. Our objectives were to study the disease biology and to find new friendly means of control of the disease including biocontrol agents in order to later structure an integrated control system that will result in reduction of chemical fungicides use and residues. O. neolycopersici conidia germination was highest at temperature 25ºC, high relative humidity (RH) and low light intensity, whereas, conidia production is higher at 22°C, lower RH and higher light intensity (but fluctuating greenhouse temp result in higher number of conidia). Under field conditions, epidemics developed faster under conditions of high RH and moderate temperature. Accordingly, we simulated conditions for significant epidemic development on potted tomato plants subjected to artificial inoculation in experimental greenhouses. While testing various yeast and bacterium isolates ,it was found that few of them reduced disease severity by up to 80% on potted plants under heavy disease pressure. However, disease suppression was better on upper leaves than on lower leaves. Disease severity was significantly higher on the lower leaves, thus control efficacy may be negatively related to the disease pressure and the time the plant organ was exposed to the pathogen inoculum and the biocontrol agent. The potential biocontrol agents did not affect the germination and germ tube elongation of the Oidium conidia. However, three of the micro-organisms reduced conidia formation on the thallus of O. neolycopersici on leaves.
