Spinach production conditions in the different types of greenhouse constructions

Abstract

Spinach is very common in the human nutrition due to its high nutritive value. It is commonly grown in the greenhouses. In region of Serbia, spinach is commonly grown in the tunnel structure greenhouses, covered with single or double PE folia without additional heating. The aim of the research was to see if different greenhouse construction types influence the microclimatic parameters in the spinach production and to see if choosing the certain greenhouse construction type can improve an overall production conditions resulting in higher spinach yield, lower energy consumption and higher energy productivity. Spinach production was tracked in the three different types of greenhouses. The round-shaped greenhouse has its base diameter of 7 m while tunnel type greenhouse was 5.5 m wide and 24 m long. Single span greenhouse was 10 m wide and 50 m long. All greenhouses were covered with PE UV IR 180 mu m folia. Results show that production conditions are dependent on type of greenhouse construction. During the winter spinach production solar radiation energy losses in the tunnel structure were 29.38% while the round-shaped greenhouse was losing 19.51% of the solar radiation energy. Losses in the single-span greenhouse were 12% in the morning hours and 43% during the day. During the day air temperatures in the greenhouses were higher. In the round-shaped and tunnel structure greenhouse this temperature difference lower than 1 degrees C and are not considered important for the plants. In the case of single-span greenhouse inside-outside differences were 2.52 degrees C up to 16.26 degrees C.