Integrated protection of fruit crops IOBC-WPRS Bulletin Vol. 91, 2013 pp. 235-241 235 Past and current situation of forecasting system in Turkey N. Mukerrem Celiker 1 , Ayse Özdem 2 , Ercan Canihos 3 , Cevdet Kaplan 1 , Nursen Ustun 1 , Naim Özturk 3 , F. Özlem Altindisli 1 1 Bornova Plant Protection Research Station, 35040 Izmir, Turkey; 2 Plant Protection Central Research Institute, 06100 Ankara, Turkey; 3 Biological Control Research Station, 01321 Adana, Turkey Abstract: Grape, apple and pear production are of great importance in Turkey. However, certain insect pests and diseases cause crop losses by impacting quality of fruits. Vine and fruit trees are protected against harmful organisms according to the timing of forecasting systems or phenological growth stages of plant. Modified Verderevsky and Popov (1975) models are used in the vineyards as a decision tool of chemical applications against downy mildew (Plasmopara viticola Berk. et M. A. Curtis) and European grapevine moth (Lobesia botrana Den.-Schiff.), respectively. In apple orchards, application times against apple scab [Venturia inaequalis (Cke.) Wint.] and codling moth [Cydia pomonella (L.)] are decided according to Mills and Laplante (1954) Table and day-degree model, respectively. Mary Blight model is the decision tool that determines application times most accurately in the control of fire blight (Erwinia amylovora Burril Winslow et al.) in pear orchards. Section of the forecasting studies carried between 1993 and 2010 against the pests and diseases mentioned above has been considered in this article. Models tested and decided, short description of equipments providing necessary data and the increase in data collecting stations and protected areas have been summarized as well as success and application numbers of pesticides according to forecasting models and plant phenology have been compared. Transition from mechanical equipments to computer-based systems has been given. Key words: Forecasting system, Turkey, grape, apple, pear Introduction Grape, apple and pear production are of great importance in Turkey. In total, 4.29 million- tons of fresh grape are produced in 480 000 ha. Respectively, the total apple production area and amount are 198 500 ha and 2.6 million tons. Not only grapes and apples but also pears are an important fruit crop grown in 47 thousand ha with an amount of 386 000 tons in Turkey. Apple scab [Venturia inaequalis (Cke.) Wint.] and codling moth (CM) [Cydia pomonella (L.)] on apple, downy mildew (Plasmopara viticola), and European grapevine moth (EGVM) [Lobesia botrana Den.-Schiff.] on grape and fire blight (Erwinia amylovora Burril Winslow et al.) on pear are the pests which cause serious crop losses in Turkey. At first, forecasting studies against the pests and diseases mentioned have been conducted in Aegean and Central Anatolia on grape, Aegean, Central Anatolia, Black Sea, South East, Mediterranean and Marmara Region on apple between the years of 1978 and 1988 as research and implementation projects of the regional research institutes working on plant protection. Nowadays, surface area protected on time according to data coming from these systems has gradually increased. Having completed research studies in different locations of Turkey between the years 1995 and 2000, MARYBLIGHT has been the most accurate model against the fire blight disease in pear growing areas. Research and implementation studies of MARYBLIGHT were done by Bornova Plant Protection Research Institute in the Aegean and Marmara Regions