Hydroponic production of cucumber in greenhouses

Rad opisuje hidroponski uzgoj, sa naglaskom na tikvenjaču Cucumis sativus L. i karakteristike njezine proizvodnje, potencijala i mogućnosti u tako intenzivnoj i kontroliranoj proizvodnji kao što je hidroponska. Salatni krastavac u hidroponskoj proizvodnji može imati prinos do 20-30 kg/m2. Za veće površine do 12.000 m2 koriste se jedinice radnog protoka 20 m3. Takve su jedinice pripremljene za rad sa 3-4 recepta. Izborom broja recepata jednoznačno je određen broj pripadajućih spremnika za hranjiva. Svaki recept zahtijeva dva zasebna spremnika, tip A i tip B. Spremnik za kiselinu je zajednički za sve recepte. U neposrednoj blizini jedinice postavlja se dodatni spremnik za vodu. Veličina tog spremnika također se određuje ne temelju prosječne dnevne potrošnje vode, koja u pravilu ne prelazi 10 lit/m2 kroz 24 sata. Najrašireniji supstrat za povrće u hidroponu je kamena vuna. Biljke se uzgajaju u hranjivoj otopini koja je bogata nutrijentima u obliku anorganskih iona. Hranjiva otopina sadrži u optimalnom odnosu sve hranjive biogene elemente, određene je pH-vrijednosti i koncentracije koja se određuje stupnjem električne provodljivosti (EC-vrijednost). Doziranjem hraniva, vode i mikroklime putem računala postiže se visoka efikasnost. Broj navodnjavanja tijekom dana ovisi o vremenu, količini svjetlosti, razvijenosti usjeva i podloge. Zbog malog volumena supstrata po biljci potrebna je učestala fertirigacija. Tako kod uzgoja na kamenoj vuni tijekom dana može biti i preko 30 navodnjavanja po danu, uz potrošenih 3-4 litre hranjive otopine po biljci. Sustav za navodnjavanje i prihranu može biti otvorenog i zatvorenog tipa. Optimalan hidroponski sustav koristi oko 90 % manje vode nego što se koristi obrađivanjem tla. Najkvalitetnije i najpogodnije zagrijavanje unutrašnjosti plastenika pri hidroponskom uzgoju plodovitog povrća ostvaruje se odgovarajućim sustavom toplovodnog grijanja putem podnog cijevnog razvoda. Sjeme krastavaca je krupnije. Može se sijati izravno u uzgojne blokove kamene vune. Vrijeme proizvodnje presadnica krastavaca ovisi o klimi i godišnjem dobu, a najčešće iznosi 21-28 dana.The paper describes hydroponic cultivation, with emphasis on the Cucumis sativus L. and the characteristics of its production, genetic potentials and possibilities in such intensive and controlled production as hydroponic. Salad cucumber in hydroponic production can have yields up to 20-30 kilo per m2. For larger areas up to 12,000 m2 are required working flow units of 20 m3. Such units are prepared with 3-4 receptions. The number of recipes is determined by number of associated nutrient containers. Each recipe requires two separate containers, type A and type B. Acid preparation is common shared by all recipes. An additional water tank is installed in the immediate vicinity of the unit. The size of this tank also determines the basis of the average daily water consumption, which as a rule does not exceed 10 liters per m2 in 24 hours. The most common vegetable substrate in hydroponics is rock wool. Plants are grown in a nutrient solution that is rich in nutrients in the form of inorganic ions. The nutrient solution contains optimal ratio of all necessary nutrients and it has established pH values and electrical conductivity (EC-value). High efficiency is achieved by dosing nutrients, water and microclimate via a computer. Number of indications during day depends on the weather, the amount of light, the development of crops and rootstocks. Due to the small volume of substrate per plant, frequent fertigation is required. Thus, when growing on rock wool during the day, there can be over 30 irrigations per day, with 3-4 liters of nutrient solution per plant. The irrigation and fertilization system can be open type or closed type system. An optimal hydroponic system uses about 90% less water than tillage, including a drip system, and has higher nutritional value of vegetables. The highest quality and most suitable heating of the greenhouse interior for hydroponic cultivation of fruitful vegetables is achieved by suitable hot water heating system through floor pipes. Cucumber seeds are larger. It can be sown directly into the growing blocks of rock wool. The time of production of cucumber seedlings depends on the climate and season and is usually 21-28 days