The prey consumption of Tuta absoluta eggs by Macrolophus pygmaeus in the presence of marigold plant

Abstract: The use of Calendula officinalis (marigold) in a banker plant system to support
Macrolophus pygmaeus (Mp) populations has been previously reported. It is considered a
valuable approach which supports the establishment of the mirid and its development.
However, in banker plant systems the movement of the predator from the companion to the
target plant is a critical aspect which has not been extensively studied. In the current study,
experiments were conducted to evaluate whether the presence of marigold influence predator’s selection rate in relation to tomato as affected by prey availability. For this reason, a tomato leaflet accompanied by a marigold leaf with or without prey were placed in Petri dishes. Also, the mirid predator position was recorded in 10 min intervals for 2 h and its prey consumption in 2 h and 24 h as well. Similar experiments were conducted in cages using a young tomato and a marigold plant. Tuta absoluta eggs were used as prey. In the dishes, the presence of a marigold leaf did not reduce the prey consumption on the tomato leaflet in the presence of prey, 2 h after the predator releasing. However, the total prey consumption was not affected by the presence of marigold plant, 24 h after Mp releasing. Also, the presence of a marigold plant without prey interestingly didn’t affect the prey consumption on the tomato plant, 24 h after Mp female individual was released in cage. Therefore, further studies should be conducted to better realize the potential of marigold to be effectively used to support Mp populations.