The latest report of the Plant Health Service of Murcia's Department of Agriculture warned that the presence of Pulvinaria polygonata, a pest that has already devastated agricultural citrus farms in Alicante's Vega Baja, had been detected on a plot of mandarins located in El Mirador de San Javier, Murcia.
This pest of Asian origin was first detected a year ago in some citrus plots in San Miguel de Salinas (Orihuela) and it is dangerously expanding in more municipalities given the low efficacy of the treatments being used against it, as this species was unknown until now in Europe. This pest mainly damages the trees because it sucks their sap weakening them. In addition, the nymphs and adult females secrete molasses on which abundant fungi develop covering the plant's leaves, branches, and fruits, which makes marketing them impossible.
The affected trees are covered with a layer of white cotton, which is the ovisacs used by the females of these insects to lay their numerous eggs. The eggs hatch giving rise to a high population in a first immature state, which disperses and stands on the leaves and branches, taking hold of them. Despite being eating a wide variety of plant species, this coccycum has a predilection for citrus.
Experts in pest treatment, such as Pablo Melgarejo, a professor of Plant Production at the Miguel Hernandez University (UMH), are worried that this pest might jump to other fruit species and cause even more havoc in a territory that has an ideal climate for them to expand.
The professor is also worried about the ease of spread of the insect. The pest could be spread by birds, other insects -such as bees, wasps, or mosquitoes-, transport boxes, and the clothes farmers use when harvesting the fruit or pruning, among other ways. "So far the only thing we think doesn't influence its spread is the wind."
Producers fear the farms will stop producing
The Pulvinaria polygonata has already devastated up to 5,000 hectares of citrus in Alicante's Vega Baja. According to estimates, producers in Alicante have already lost 100,000 tons of fruit, mainly lemons, to this new plague. The plots in which the pest was initially detected a year ago have stopped producing and the producers fear the same will happen in the coming months to the farms where it is expanding.