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As part of the vegIMPACT project a laboratory test in the Netherlands was done with potato (Solanum tuberosum) var. Bintje and onion (Allium cepa) var. Sturon. In both crops mancozeb was sprayed with and without the adjuvants Bond and Indostick. In both crops these three treatments were applied with high and low spray volumes. After spraying, rain was simulated (0.5, 3 or 6 hours after spraying and a control without rain) to test the sticker properties. After five days, plant leaves were analysed on mancozeb residue. Five days after spraying the potato plants were inoculated with Phytophthora infestans and onions with Peronospora destructor. Subsequently, disease symptoms were observed and visually rated as percentage of infected leaves. In potato lower mancozeb residue levels were measured at high spray volumes. Under dry conditions the effect of adjuvant on mancozeb residue in potato was limited. In onion the spreader characteristics of the adjuvants resulted in higher mancozeb residue concentrations than without adjuvant. The impact of rain simulation was much bigger than the impact of adjuvant on mancozeb residue and late blight incidence. Therefore, it is not recommended to spray when rain is expected within the same day as spraying. With rain simulation in both onion and potato more mancozeb residue was present when using the adjuvant Bond than when spraying mancozeb without an adjuvant. However, also with Bond after rain simulation high amounts of mancozeb were washed off. Mancozeb with Bond in potato resulted in less late blight incidence than with spraying mancozeb without adjuvants. Overall the adjuvant Bond performed better than Indostick in terms of mancozeb retention on both potato and onion leaves . Indostick had good spreading properties that under dry conditions resulted in higher mancozeb residue levels in onion. Under rainy conditions the effect of Indostick on mancozeb residues was not or only slightly better than mancozeb without adjuvant.

Demo plots with potato varieties Atlantic and Granola were laid out in Garut and Pangalengan from October 2014 to January 2015. The objective of the demo plots described in this report are to investigate the influence of three factors on the efficacy of three factors in late blight control strategies:Test the influence of fungicide product choice on the efficacy of late blight control in the most susceptible variety Atlantic; Test the influence of spray volume on the efficacy to control late blight both in Atlantic and Granola; Test the influence of the adjuvant Agristick at normal and reduced spray volumes both in Atlantic and Granola.

Late blight caused by Phytophthora infestans is one of the most important diseases worldwide. Also in Indonesia control of late blight is very important in potato and tomato, especially in the rainy season. In order to learn more about the important factors that determine late blight control - such as product choice, application frequency, spray volume and use of adjuvants - two demo plots were laid out in the potato growing regions of Garut and Pangalengan. The treatments in the demo-plots consisted of different fungicide application strategies.

Field experiments were carried out in Denmark, United Kingdom and the Netherlands in 2009, 2010 and 2011. Thus nine experiments were carried out to compare the effectiveness against tuber blight by measuring the protection of leaves and tubers against infection by late blight caused by application of a fungicide in a standard 7-day spray schedule. This report describes the analysis of the efficacy of fungicides to control potato tuber blight during the second part of the season. A tuber blight rating was established for five fungicides.

Phytophthora infestans is the most devastating disease in potato cultivation. Chemical control is necessary to ensure a healthy crop. At the same time Dutch governmental policy asks for a reduction of the environmental impact of potato late blight control by 75% in 2012 as compared to 1996-1998. The aim of the experiments was to compare Decision Support Systems with different approaches to blight risk management for their ability to reduce the fungicide input without compromising control efficacy. Considerable savings, up to 81% when compared to weekly, full dose rate, spray schedules, can be achieved by using information on cultivar resistance, length of the critical period and disease pressure to decide whether or not to spray. The subroutine calculating the potential for viable transport of spores is only effective on resistant varieties as the threshold was exceeded with every critical period on less resistant cultivars. Implications of the experimental control strategies for agricultural practise are discussed

Partners from the EuroBlight network, with support from ENDURE, created a freely available platform that allows testing and comparing weather-based late blight models (www.euroblight.net). The platform contains extensive weather data: hourly data from many European Union countries, both north and south, between 2006 and 2009. It also contains seven different weather based late blight sub-models. Most recently, biological data for verification were uploaded from monitoring of field experiments and potato fields around Europe. The results from different models for disease risk or, infection risk give similar but by no means identical results. The tool is intended to improve the quality of existing sub-models and it will be used to analyse the weather based risk of late blight development in different regions of Europe and beyond

Endure projectnummer 031499