One of the pests that troubles British farmers is the pollen beetle, Meligethes aeneus, which is particularly fond of yellow flowers and is a menace to oil seed rape. On some plants it is a beneficial pollinator, but on oilseed rape it destroys the plant’s ability to produce the all-important seed.
The normal method of control is spraying with pesticide. Unfortunately, this also kills pollinators like bees, plus spiders and insects that would otherwise eat the pollen beetle’s larva. With insect numbers falling dramatically, partly because of pesticide use, other solutions to controlling the pollen beetle are being sought. Scientists from Würzburg, Germany, have been experimenting with growing field margins and insect refuges sown with wild flowers so predators of the pollen beetle can thrive.
A year after planting the refuges, pollen beetle numbers were vastly reduced without using any pesticides on the rape. For a crop that has become very important this could prove a valuable way of managing a difficult pest. This is particularly relevant because some of the more effective but environmentally damaging pesticides have recently been banned. If the normal balance of nature could be restored, insects and farmers would both benefit.
