The efficacy of Milsana Ò VP 1999 and 2000 (a formulated plant extract of Reynoutria sachalinensis), known to induce resistance to powdery mildew on cucumbers, was tested against Leveillula taurica (Le´v.) Arn. on greenhouse tomato. In four out of five trials, Milsana Ò achieved a disease reduction ranging from 42.2 to 64.6%. In one trial only, its efficacy was exceptionally low (23%). Application rates and disease pressure proved to be the main factors affecting the level of control. Milsana Ò was significantly less effective than fungicides (alternated DMIs and penconazole) in situ. In contrast, Milsana Ò was equally effective to wettable sulphur indicating that its effect was rather preventive than curative. The level of efficacy achieved by either Milsana Ò or fungicides did not result in a significant increase of yield. Laboratory tests showed that Milsana Ò (VP 1999) had a direct effect on conidial germination. Whether this effect significantly contributes to its field efficacy, remains to be elucidated. Overall, results indicate that Milsana Ò could play an important role in disease management of powdery mildew in organic and low input tomato production.

Copper (Cu) is naturally present in all soils with a normal range of 2 -60 mg kg 21 . The traditional use of Cu fungicides against mildew diseases has led to the accumulation of Cu in some vineyard and orchard soils. Consequently, there is a move to reduce the use of these compounds in agriculture, especially in organic cultivation. A comprehensive study has not been made of the Cu content of Greek agricultural soils, which are typically alkaline with high clay content and may, therefore, be vulnerable to Cu accumulation. Within the framework of various projects, surface soil samples were taken from 10 different regions of Greece for various representative crops, and especially, for fallow soil and abandoned land. The samples were analyzed for total (aqua regia digestion) and DTPA-extractable Cu content and for several physical and chemical properties. Mean values of total Cu for the different regions of the country ranged from 16 (Limnos and Thera) to 89 mg kg 21 (Nemea), with an overall mean of 38 + 26 mg kg 21 . Significantly lower Cu content (27 mg kg 21 ) was found for annual than for other crops. The mean values for fallow land, vines, and olives were close to the overall mean, but for citrus the mean value was slightly higher. The highest value of 70 mg kg 21 was found for orchards/nuts

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