INTRODUCTION: Strawberry (Fragaria x ananassa Duch.) is the most important berry fruit crop in Bosnia and Herzegovina, along with raspberries. As reported by FAO (Food and Agriculture Organization of the United Nations), strawberries are produced on a total of 372,361 ha worldwide. According to the data for 2020, 8.33 million tons of strawberries were produced worldwide. In Bosnia and Herzegovina, strawberries are produced on an area of 1337 ha, and the average yield per hectare is 8.5 tons (Agency for Statistics of B&H). Strawberry is a species where a large number of pests and pathogens occur. This can lead to economically significant losses, and in some cases, the decline of the plantation itself. A large number of phytopathogenic fungi are listed worldwide that cause diseases of cultivated strawberries, of which species from the genera Botrytis, Colletotrichum, Phytophthora and Verticillium are of the greatest economic importance. The most important strawberry pests worldwide are species from the genera Lygus, Otiorhynchus, Anthonomus, aphids, thrips, mites and, more recently, the spotted wing drosophila Drosophila suzukii. The incidence of diseases and pests depends on the area of cultivation, the method of strawberry cultivation and the sensitivity of the cultivar itself. The occurrence of diseases and pests on strawberries in Bosnia and Herzegovina is poorly studied and scientific papers on this issue are rare and mostly outdated. In the absence of domestic breeding centrs, foreign strawberry cultivars, mostly of Italian origin, are mainly present in the cultivation. There are few data on the susceptibility/resistance of these cultivars to fungal pathogens and strawberry pests. The objective of this research are to determine the causes of fungal diseases and pests that occur on strawberries depending on the growing region and strawberry cultivars. This research also aims to evaluate the susceptibility/resistance of the tested strawberry cultivars in different growing areas and evaluate the need for protection measures based on the intensity of disease infection and the intensity of pest occurrence. MATERIALS AND METHODS: The study was conducted during three vegetation seasons in 2009, 2010 and 2011. The Frigo plants of 10 different strawberry cultivars ('Antea', 'Arosa', 'Camarosa', 'Clery', 'Galia', 'Madeleine', 'Marmolada', 'Naiad', 'Siba' and 'Tethis') were planted in two experimental fields in Žepče on the Donja Papratnica site (Zenica - Doboj County) and in Ljubuški on the Veljaci site (West Herzegovina County). At each site, 200 plants of each cultivar were planted in the rows on the 1.2 m wide black mulch PVC foil. A drip irrigation system was installed under the foil. The experiments were set up according to Randomized Complete Block Design (RCBD). To get a clearer picture of which diseases and which pests of strawberries occur and with what intensity, no pesticides were used during research. The susceptibility to fungal diseases of individual strawberry cultivars was monitored based on the intensity of infestation several times during the growing season from the appearance of the first symptoms to the end of the growing season. The intensity of leaf infestation was evaluated according to a scale: 0 - healthy leaves without disease symptoms; 1 - spots cover up to 10 % of leaf surface; 2 - spots cover 10 – 20 % of leaf surface; 3 - spots affect 20 – 40 % of leaf surface; 4 - spots cover 40 – 60 % of leaf surface; 5 - spots cover over 60 % of leaf surface. Disease index was calculated according to the Mc Kinney formula. Susceptibility to fungal diseases of fruits was evaluated on each cultivar by examining all fruits on 20 randomly selected strawberry bushes. The results were presented as the percentage of fruits with a disease symptom in relation to the total number of examined fruits. The samples of infected strawberry plant parts were taken to the Department of Plant Protection, Faculty of Agriculture and Food Technology, the University of Mostar for isolation and determination of fungi causing the disease. Determination of fungal species was done based on the morphological characteristics of sporulation organs (fruiting bodies, spores) after incubation in humid chambers. Isolation of pathogenic fungi in pure culture was carried out by conventional methods on potato dextrose agar (PDA). The time of emergence and population of pest was measured by visual inspection of strawberry bushes several times during the growing season. To collect strawberry pests of smaller body dimensions entomological nets and hand aspirators were used. Yellow and blue sticky boards were used as a visual attractants. Pheromone traps VARb3k and VARb3z from the Hungarian manufacturer Csalomon were used to monitor the population of hairy scarab Epicometis (Tropinota) hirta and white-spotted rose beetle Oxythyrea funesta. The identification of collected strawberry pests was done based on morphological characteristics of individual species using all available identification keys. To be able to perform accurate determination, larvae (caterpillars) of individual species collected by visual inspection were grown to an adult form in the entomological cages. For statistical processing of the obtained data, analysis of variance (ANOVA) was calculated using the software SPSS 16 (Statistical Package for the Social Sciences), and for comparison of average values, the LSD test (p = 0.05) was applied. RESULTS AND CONCLUSIONS: Based on the symptoms of infected strawberries and morphological characteristics of fungal isolates in pure culture, a total of 7 fungal species were identified. The following species were identified at Donja Papratnica site (continental area): Mycosphaerella fragariae, Gnomoniopsis comari, Phomopsis obscurans, Botrytis cinerea and Colletotrichum acutatum. Seven species were identified at the Veljaci site (Mediterranean area): M. fragariae, G. comari, P. obscurans, Diplocarpon earlianum, Podosphaera aphanis, C. acutatum and B. cinerea. The common leaf spot (M. fragariae) was found at both sites and the symptoms of the disease were present in all strawberry cultivars. Disease severity and the intensity of the symptoms varied significantly from year to year and between sites. Disease severity at the Donja Papratnica site ranged from 1.2 on the cultivar 'Galia' to 13.3 on the cultivar 'Madeline'. At Veljaci location, disease severity and the intensity of the appearance of symptoms of common leaf spot were more pronounced during all three years of the study. The intensity of infection at this site ranged from 6.4 on the cultivar ‘Galia’ to 38.7 on the cultivar ‘Madeleine’. Gnomonia leaf blotch (G. comari) was detected at both sites during all three years of the experiment. The 'Galia' cultivar showed the greatest susceptibility to the pathogen G. comari. The ‘Marmolada’ and ‘Antea’ cultivars were susceptible, while the ‘Camarosa’ and ‘Tethis’ cultivars were less susceptible to this pathogen. Symptoms of gnomonia leaf blotch were not found on the 'Madeleine' cultivar. Infection of strawberries with leaf scorch (D. earlianum) was found only at the Veljaci site. The first symptoms of this disease were observed on the leaves of strawberries in early May. There were statistically significant differences in the susceptibility of cultivars to this pathogen. Symptoms of the disease on the 'Madeleine' cultivar during the three-year research were not found. The cultivars 'Naiad' and 'Arosa' were also less sensitive. The cultivar 'Siba' was the most sensitive to the to the strawberry leaf scorch, but it did not differ statistically significantly in sensitivity from the cultivars 'Galia', 'Clery', 'Tethis', 'Camarosa', 'Marmolada' and 'Antea'. Symptoms of leaf blight (P. obscurans) were found during all three years of research at both sites. The appearance of symptoms was sporadic and this disease, according to the results of our research, has no greater significance. Symptoms of leaf blight were found on the cultivars 'Antea', 'Arosa', 'Clery', 'Galia', 'Marmolada', 'Naiad' and 'Siba'. Due to the long incubation period, the expression of the symptoms of the disease in our agroecological conditions occurs during July. During our research, we determined the infection of strawberries with powdery mildew only at the Veljaci site, on the cultivars: 'Arosa', 'Camarosa', 'Clery', 'Galia', 'Naiad', 'Siba' and 'Tethis'. In 2009, powdery mildew appeared at the Veljaci site with greater intensity in mid-May and again at the beginning of October. The cultivars that showed the highest susceptibility to powdery mildew were ‘Siba’ with an infestation index of 56.4 and ‘Naiad’ with an infestation index of 53.2. Considering the three-year average, the highest percentage of fruits with symptoms of gray mold B. cinerea at the Donja Papratnica site was recorded on the cultivars 'Marmolada' 39.3 %, 'Antea' 38.5 % and 'Arosa' 35.6 %. The lowest percentage of fruits with symptoms of gray mold was recorded on the cultivar 'Camarosa' 20.4 %. The highest percentage of fruits with symptoms of gray mold at the Veljaci site was recorded on the cultivars 'Arosa' 17.5 % and 'Galia' 17.4 %, and the lowest on the cultivars 'Tethis' 7.3 % and 'Camarosa' 8.5 %. Strawberry anthracnose, coused by Colletotrichum acutatum was determined at both localities. The highest percentage of fruits with symptoms of anthracnose was recorded in the cultivars 'Marmolada' 7.6 % and 'Madeleine' 7.0 % in the Donja Papratnica site. At this site, 49 strawberry pests were determined, which systematically belong to 28 different families, ie 8 orders. At the Veljaci site, 59 pests from 22 families, ie 8 orders, were determined. Species from the order Orthoptera, genera Pholidoptera spp., Omocestus spp. and Pezotettix spp. were determined at the Donja Papratnica site. Higher abundance of the species Decticus albifrons Fabricius was recorded at Veljaci site. Other species of the order Orthoptera determined at the Veljaci site were: Tettigonia viridissima L., Ephippiger ephippiger Fiebig and also species of the genera Pachytrachis spp., Oedipoda spp., Euchorthippus spp. and Omocestus spp. During the research, a total of 17 different species of leafhoppers from the genus Cicadellidae, Cercopidae, Cixiidae, Delphacidae and Membracidae were determined. With their high abundance the species Edwardsiana rosae L., Philaenus spumarius L., Cercopis vulnerata Rossi and also the species from the genus Eupteryx spp. could be highlighted. The species Trialeurodes vaporariorum Westwood was determined at both localities. In the experimental field ten species of the true bugs from the families Miridae, Pentatomidae, Coreidae, Lygaeidae and Pyrrhocoridae were determined. The species Aphis forbesi Weed and Chaetosiphon fragaefolii Cock. belonging to Aphididae family were determined at both sites. A more severe infestation of the strawberry root aphid A. forbesi was recorded during 2010 at both sites. Two species from the order Hymenoptera, family Tenthredinidae; Allantus (Emphytus) calceatus Klug and Allantus (Emphytus) cinctus L. were determined. Besides, seven species from the family Curculionidae, genera Anthonomus, Otiorhynchus, Strophomorphus, Phyllobius, and Sitona were determined. The most significant strawberry pest at the Donja Papratnica site was the strawberry blossom weevil Anthonomus rubi Herbst. Damage to flower buds from strawberry blossom weevil was present throughout all three years of research, and the intensity of damage increased with the age of the plants. The greatest damage from A. rubi at Donja Papratnica site was recorded during 2011, and the percentage of damaged flowers ranged from 3.3 % on the cultivar 'Galia' to 7.4 % on the cultivars 'Marmolada' and 'Clery'. Species that belonging to the genus Otiorhynchus; Otiorhynchus ovatus L., O. rugosostriatus Goeze, and O. corruptor Host were determined. Significant damage to strawberry flowers due to hairy scarab E. hirta was recorded at the Veljaci site. The intensity of damage from this species varied depending on the year of cultivation and strawberry cultivars. The highest percentage of strawberry flowers damaged by E. hirta was recorded on the cultivars 'Clery' 20.1 % and 'Madeleine' 18.0 % during 2011. The lowest percentage of damaged flowers was recorded in cultivars 'Camarosa' 9.5 % and 'Galia' 9.6 %.