Impact of aromatic plants on olive trees production

Abstract

ABSTRACT Plants interact in positive ways, facilitating each other. We can use this facilitative effect in agriculture by intercropping crop plants with aromatic plants that provide benefits such as the repulsion of pests, resulting in a reduction of agrochemical inputs and higher crop productivity. Considering this potential benefit, we conducted a study in an olive grove to test the effect of the aromatic plants basil (Ocimum basilicum) and rosemary (Salvia rosmarinus) on olive (Olea europaea) production. We planted six aromatic saplings under olive trees (20 trees with basil and 20 with rosemary) and selected 20 olive trees with no aromatic plants as a control group. To estimate the productivity of olive trees, we measured the number of inflorescences per tree, the number of fruits, and the average fruit weight. After nine months, we did not find a significant difference in the productivity of olive trees intercropped with aromatic plants compared to olives without the association. However, basil and rosemary had low mortality rates and showed substantial growth. Consequently, while probably not increasing olive production, the absence of negative effects on olive productivity indicates that intercropping aromatic plants and olives is viable and might provide diversification and economic resilience to small farmers.

Keywords

• basil (Ocimum basilicum)
• facilitation
• olive (Olea europaea)
• plant-plant interaction
• rosemary (Salvia rosmarinus)