Estimating the energy gap in greenhouse cucumber production

The energy gap of greenhouse cucumbers in this research was investigated due to Iran’s large greenhouse cultivation area and the high input energy entrance into these agroecosystems. Accordingly, single-flower, double-flower, middle-flower, and multi-flower cucumber varieties were cultivated at distances of 37, 42, and 47 cm. The important achievement of this research is making it possible to calculate the energy gap by the yield gap calculations. The turning point is breaking the yield gap into its constituent units, which are caused by management and arrangement, and determining the role of each one in their share of the yield gap. The results showed that up to 104 tons/ha of yield gap was created in the worst case by choosing the wrong variety and inappropriate planting distance, which is equivalent to 83,000 MJ/ha (104 tons/ha) of lost energy in multi-flower varieties. This amount reduced up to 62 tons/ha in middle flower varieties, which is equivalent to 49,000 MJ/ha of lost energy. Indeed, agroecosystems achieved higher output energy by spending specific input energy, which is the basis for sustainable agriculture and reducing the resources lost on a large scale. Accordingly, in this research, it was found that by reducing the loss of yield due to the incorrect choice of planting distance and cucumber variety, we will achieve higher output energy by consuming the same amount of input energy.