Nimble Plum Thickened

2024 Author: Gavin MacAdam | [email protected]. Last modified: 2023-12-16 13:38

The plum thick-stemmed pest is a pest of fruit crops, which is most active in the northern steppe and in the forest-steppe. From its name, we can conclude that it only harms the plum, but this is not at all the case - the plum thickened will not refuse to feast on cherry plum, and sweet cherries, and thorns, and apricots with cherries on occasion. Therefore, in order to avoid massive loss of fruits, it is necessary to get rid of this nimble villain as soon as possible

Meet the pest

Adult plum thick-stems are endowed with a very slender black body, convex breasts and shiny oval abdomens sitting on small stalks. The paws and legs of the pests are yellowish, the eyes are black, and their transparent wings are equipped with one longitudinal vein each. Males reach a length of about 4 - 5 mm, and females - 5 - 6 mm.

Oval and rather cloudy glassy eggs of pests, the size of which is about 0.6 mm, have small processes and long stems at the front ends. The little white elongated larvae of the younger instars are devoid of legs and slightly bent, while the milky-white individuals of the older instars are barrel-shaped and grow up to 6 mm in length. Pupae, which grow up to 5 mm, are initially milky-white, and just before the emergence of the imago they gradually turn black.

The overwintering of larvae that have completed feeding takes place inside the fruit seeds. And they begin to pupate in the spring, as soon as the average daily air temperature reaches eleven to twelve degrees. The pupation period is slightly extended in time and can last up to a month, and the development of pupae takes from thirteen to sixteen days. The adults emerge through round holes up to 1.5 mm in diameter gnawed by them in the bones. To gnaw such holes, pests spend from three to six days! If the bones have time to dry, then the insects will no longer be able to get out of them.

Five to six days after the plum has bloomed, the plum tree starts years. And soon after the departure of the pests, their mating occurs. The adults, which are most active at temperatures from sixteen to eighteen degrees, live on average from six to eight days.

Approximately on the third or fourth day after departure, plum thick-stems start laying eggs. Females, piercing the ovaries of fruits with the help of sharp ovipositor, are placed inside the seeds that did not have time to harden, one egg at a time. In this case, the total fertility of pests reaches three to four dozen eggs.

It takes about sixteen to twenty days for the embryonic development of plum thick-stems. At first, the reborn larvae are located near the walls of the bones, and after some time they begin to move inside the nucleoli and bite into them. In literally twenty-five to thirty days, the harmful larvae eat the nucleoli almost entirely - only a powdery loose mass remains of them. Around the end of June, damaged fruits begin to massively crumble from trees, reaching their maximum by the first half of July. And the larvae that have finished feeding continue to remain in the bones until spring. Most of them (slightly more than half) enter diapause and often overwinter a second time, and some individuals are able to overcome as many as three winters!

How to fight

Fallen damaged fruits must be promptly collected and destroyed. In the fall, the soil should be cultivated both in the aisles and in the near-trunk circles - from the bones that are in it at a depth of six to ten centimeters, adults are not able to get out. And if more than ten percent of the seeds are populated with plum tolstopods, then six to seven days after the plum blooms and the massive years of pests begin, fruit trees begin to be treated with insecticides.