The advantage of Decision Support System for managing spring barley disease in Estonia

P. Sooväli¹*, M. Koppel¹, E. Lauringson² and L. Talgre²

¹Crop Research Institute, J. Aamisepa 1, EE48309 Jõgeva, Estonia
²University of Life Sciences, Kreutzwaldi 1, EE51014 Tartu, Estonia
*Correspondence: pille.soovali@etki.ee

Abstract:

A Decision Support System (DSS) I-Taimekaitse focusing on use of timely applied and reduced fungicide rates in control of cereal diseases has been tested in field trials since 2003. We compared the conventional treatment and the DSS-based spray practices in 18 field trials in five agricultural locations over 7-year period. Efficacy of the control of net blotch caused by Pyrenophora teres (Drechsler, am Drechlera teres Sacc. Shoem), the main fungal disease in spring barley has been tested to determine the economic advantage of DSS use. Compared with the conventional spray practices, the advantage I-Taimekaitse resulted in reduction of application doses by 30 to 60% of the registered rate. According to I-Taimekaitse, the fungicides were applied mainly between heading and flowering growth stages (GS 55–65), whereas traditional routine spraying is commonly made at booting (GS 37–49). The experiment clarifies the cost-benefit of using DSS-based approach in barley disease management with average yield increase above the control in 12.8% and above the conventional treatment in 14.1%. I-Taimekaitse gave competitive disease control and average yield output reduction compared with conventional practice by 9%. In general the Treatment Frequency Index applied in conventional treatment was 0.65 and in DSS 0.41. Although the cost of treatment expense in DSS was 20% less compared with conventional practice, the performance of conventional used spray practices was outstanding in economic return.

Key words:

decision support system, economic return, fungicide, net blotch, spring barley

NegFry – DSS for the chemical control of potato late blight – results of validation trails in Tartu

V. Eremeev, A. Lõhmus and J. Jõudu

Institute of Agricultural and Environmental Science (IAES), Estonian University of LifeScience, Kreutzwaldi St. 64, EE51014 Tartu, Estonia; e-mail: Viacheslav.Eremeev@emu.ee

Abstract:

Potato late blight, caused by the oomycete fungus Phytophthora infestans (Mont.) de Bary is the most destructive disease affecting the potato worldwide. For controlling the disease, most manuals recommend that growers apply fungicides at regular intervals of 8–10 days from the time of row closing until the end of the growing season. The NegFry model was used for timing the chemical control of potato late blight. The NegFry model is based on two existing models, the ‘negative prognosis’, for forecasting the risk of primary attacks, and a model for timing subsequent fungicide applications during the season. The main objective of NegFry is to get high yield and quality with minimum use of fungicides.Present work underscores that NegFry has given a positive result by timing the firstspraying for anticipation of the infection and by optimizing the number of treatments for late blight control.

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