Effects of grafted seedlings on energy indices and greenhouse gas emissions in watermelon cultivation

Abstract

This study was carried out in order to analyze and compare energy indices and greenhouse gas (GHG) emissions of grafted and non-grafted watermelon production over three years. First, seedlings (grafted and non-grafted) were cultivated in a greenhouse and then manually planted on six plots (each type on three plots). Energy consumption, watermelon production, energy indices, and GHG emissions were measured and calculated on each plots. The results indicated no significant difference in average energy consumption between grafted and non-grafted watermelon cultivation. However, there was a very significant difference in their energy indices (p<0.01). Energy ratio, energy productivity, specific energy, and net energy gain for non-grafted watermelon were 2.88, 1.52 Kg MJ^-1, 0.66 MJ Kg^-1, and 51,551.41 MJ ha^-1, respectively. For grafted watermelon, these values were 3.65, 1.92 Kg MJ^-1, 0.52 MJ Kg^-1, and 72,237.01 MJ ha^-1, respectively. GHG emissions for grafted and non-grafted watermelon production were 1480.32 and 1395.82 KgCO2eq ha^-1, respectively. As a result, Grafting of watermelon seedlings reduced energy consumption and GHG emissions for one kg watermelon production by 26.3 and 15.15%, respectively.