The gypsy moth is a destructive insect pest infesting New Jersey’s forests, destroying thousands of acres of trees. In the New Jersey Pinelands, the gypsy moth is also an occasional pest of cranberries. Gypsy moth caterpillars will readily eat the plants in outbreak years, when they are abundant in the Pinelands, like in 2007. The caterpillars prefer to feed on oaks, but when they encounter cranberry plants, their presence can have a devastating effect. Fortunately, since 2007, the caterpillars have rarely been seen in the New Jersey Pinelands. However, this doesn’t mean we shouldn’t be prepared for their eventual return. Also, studying cranberry resistance against gypsy moth will teach us about the resistance of the plants against other important pests as well.
At the Rutgers Marucci Cranberry and Blueberry Research Center in Chatsworth, NJ, studies led by postdoctoral student Elvira de Lange are currently testing the insect resistance of seven varieties of cranberry, including the widely used Stevens variety and newer varieties such as Crimson Queen and Demoranville. De Lange started off wrapping the different plants in white polyester sleeves and adding a number of gypsy moth larvae that just hatched from the egg. A week later, she retrieved the larvae from the plants and weighed them, to evaluate whether or not they grew well on certain plants. Also, she scored the damage the gypsy moth evoked, as a measure for plant resistance. She is still evaluating the data, in order to know if certain cranberry varieties are more resistant than others. [Read more...]