Formation characteristics and control of Plutella xylostella

Morphological features: the adult is orange-yellow, with filamentous brown diagonal antennae, converging at one point on the wing tip. It is inverted v-shaped, the hind wings are grayish yellow, the feet are brown, the eggs are flat and oval, yellowish. The larva is slightly rectangular, the front end is slightly larger, the body color is bright, the body back moth has a large purple spot, and the head is dark brown. The cocoon is oval. 12mm or so, hard, gray-white, with black stripes, all on the branches or branches of the stem. The yellow diamondback moth produces one generation a year, overwinters with mature larvae on the plant, and pupates from May to June of the following year. The larvae lie still on the back of the leaves during the day and feed at night. Harm to the epidermis and mesophyll tissue under the leaf, serious can eat up the mesophyll, leaving only veins and petioles, serious harm to the rose. Control methods: (1) combined with winter pruning, remove the overwintering cocoons on the branches. (2) using black light to catch and kill adults. (3) spraying 90% trichlorfon 500 × 1000 times during larval occurrence, or spraying 20% pyrethroids 1000 × 2000 times; (4) protecting enemies, such as wasps, long-legged wasps, mantis and so on.