Importance of honey bee (Apis mellifera) in the pollination of the organic apple orchard

: Poznato je da su medonosne pčele (Apis mellifera) odgovorne za oprašivanje većine voćnih vrsta i cvjetajućih biljaka opčenito. Uz ostale oprašivače, od kojih su najvažniji solitarne pčele i bumbari moguće je oprašivanje velike većine biljaka cvjetnica. Istraživanje je provedeno je 29. travnja 2022. godine prilikom čega je provedeno po dva mjerenja, odnosno mjerenje u prijepodnevnim i mjerenje u poslijepodnevnim satima. Završna faza pokusa provedena je 19.07.2022. godine prilikom čega je mjerena uspješnost oplodnje i veličina plodova. U prvom mjerenju utvrđeno je kako je najbrojniji oprašivač bio medonosna pčela sa ukupno 43 posjeta. U drugom mjerenju utvrđeno je kako su izolirani cvjetovi svi ostali bez ploda, odnosno nisu oplođeni. Uspješnost oplodnje kod cvjetova koji su djelomićno bili izolirani iznosi 20 % dok postotak uspješnosti zametanja ploda kod cvjetova koje je čovjek umjetnom oplodnjom pokušao oploditi iznosi 40 %. Cvjetovi koji su bili otvoreni čitavo vrijeme ostvarili su najveću uspješnost u oplodnji, postotak oplodnje iznosi 100 %.Honey bees (Apis mellifera) are known to be responsible for the pollination of most fruit species and flowering plants in general. With other pollinators, the most important of which are solitary bees and bumblebees, it is possible to pollinate the vast majority of flowering plants. The research for this diploma thesis was carried out on April 29, 2022, during which two measurements were carried out, i.e. a measurement in the morning and a measurement in the afternoon. The final observation was carried out on July 19, 2022. during which fertilization success and fruit size were measured. In the first measurement, it was determined that the most numerous pollinator was the honey bee with a total of 43 visits. In the second measurement, it was determined that the isolated flowers were all fruitless, i.e. not fertilized. Fertilization success in flowers that were partially isolated is 20%, while the percentage of fruit set success in flowers that humans tried to fertilize by artificial pollination is 40%. Flowers that were open all the time achieved the highest fertilization success rate, with the fertilization percentage of 100%