Physiology of hydrangea flower color shange

Velelisna hortenzija je listopadni grm koji potječe iz porodice Hydrangeaceae. Biljka se na latinskom zove Hydrangea macrophylla, a naziv potječe od riječi hydro – voda i aggeion – posuda. Porijeklom dolazi iz istočne Azije i Sjeverne Amerike, a u 18. stoljeću je donešena u Europu gdje se nastavlja uzgajati kao ukrasni grm. Grm u prosjeku naraste oko 100 cm, a može biti širok i do 200 cm. Grm odlikuje velikim sjajnim nasuprotno smještenim listovima i velikim cvjetnim glavicama koje se sastoje od sitnih fertilnih i većih sterilnih cvjetova. Hortenzija je specifična zbog svoje sposobnosti mijenjanja boje cvijeta. Na promjenu boje najviše utječu prisutnost aluminijevih iona u tlu, reakcija tla i biljni pigment zvan delfidin-3-glukozid. Boja cvijeta hortenzije može varirati od svijetloplave, plave, tamnoljubičaste, ružičaste pa sve do svijetloroze. Bijela boja cvijeta se ne može mijenjati i na nju ne utječe ni jedan od navedenih čimbenika. Na grmu se čak može pojaviti cvjetna glavica sa kombinacijom više boja.Big-leaf Hydrangea is a deciduous shrub from the Hydrangeaceae family. The plant is called Hydrangea macrophylla in Latin, and the name comes from the words hydro – water and aggeion – vessel. Originally from East Asia and North America, it was brought to Europe in the 18th century, where it continues to be cultivated as an ornamental shrub. The bush can grow on average up to 100 cm and it can be up to 200 cm wide. The shrub is characterized by large glossy oppositely placed leaves and large flower heads consisting of small fertile and large sterile flowers. The hydrangea is specific because of its ability to change color of the flower. The color change is mostly influenced by the presence of aluminum ions in the soil, soil reaction and a plant pigment called delphinidin-3-glucoside. The color of the hydrangea flower can vary from light blue, blue, dark purple, pink to light pink. The white color of the flower cannot be changed and is not affected by any of the above factors. One inflorescence on the bush can even have multi-colored flowers