2024 Author: Gavin MacAdam | [email protected]. Last modified: 2023-12-16 13:38
The black beet weevil lives mainly in the southern forest-steppe regions and in the steppe. It damages about one hundred and thirty species of various plants. These include beets, cabbage, sunflowers, annual and perennial legumes, strawberries, hemp and other crops. Beetles devour young leaves and cotyledons with appetite, and harmful larvae cause significant harm to root crops, gnawing small roots
Meet the pest
The black beet weevil is a shiny black beetle that ranges in size from 6 to 10 mm. Below, the body of the pests is covered with a light grayish fluff. The rostrum of voracious parasites is wide and short. The elytra and pronotum are convex, slightly rounded, accrete along the suture and covered with small punctate grooves. And the wings of black beet weevils are generally absent.
The eggs of harmful parasites are white, oval and about 1 mm in size. Light yellow, slightly curved larvae grow in length from 12 to 16 mm and are endowed with dark brown upper jaws. Their rather wide thoracic plates are painted in pale green tones, and the anal segments are equipped with twelve stiff bristles of impressive length. The size of the pupae ranges from 7 to 10 mm. Initially, they are characterized by a white color, and before turning into bugs, they turn brown. Pronotum in pupae rather weakly curved, and at the tips of their apical segments one can observe a pair of styloid processes directed posteriorly.
The beetles of the new generation, as well as the beetles remaining for the second hibernation, overwinter at a depth of twenty to forty centimeters in the soil. In a similar way, the larvae, who did not have time to complete their development before the fall, are wintering. A single release of bugs can be observed already in April, when the thermometer rises to seven or nine degrees. As for the massive release of parasites and their subsequent dispersal, they start after the soil warms up to twelve degrees.
For bugs, a rather hidden way of life is characteristic, and they concentrate mainly near forage crops. With the establishment of cool weather and at night, black beet weevils burrow into the surface soil layer. Their main food is young shoots and leaves, however, sometimes harmful parasites can damage the generative organs of growing crops. Adults live for two seasons.
As for reproduction, in black beet weevils, it occurs parthenogenetic way. Pests lay eggs to a depth of three to five centimeters in the soil. Their laying period is quite extended - it starts from the end of April and lasts until August. In the first and second years of life, the average fertility of harmful parasites is approximately sixty to seventy eggs, and the maximum possible number of eggs that they are able to lay is equal to three hundred. Embryonic development of pests takes from twenty-eight to forty-five days. The hatched voracious larvae develop mainly on beet roots. The roots of other cultures are populated by them much less frequently. Larvae of the fourth and fifth instars complete their development in the second year of life in July or August.
For pupation, the larvae move into soil soils, and after twenty-five to thirty days, bugs are formed, the bulk of which remains in the soil until the spring of next year. However, with sufficient moisture, as well as with the establishment of rather warm weather, they can get out on the soil surface in the autumn. And as soon as the cold sets in, the bugs immediately begin to burrow into the soil to a depth of ten to twenty centimeters. For black beet weevils, a two-year generation is characteristic.
How to fight
The main preventive measures against black beet weevils are adherence to the technology and technique of growing beets, systematic loosening of the soil during the egg-laying period of pests, feeding beet crops with ammonia water and deep plowing of areas in the fall. If the number of harmful parasites on the site is too high, spraying with insecticides is allowed.
A lot of black beet weevils and natural enemies - fungal diseases of larvae, birds, predators and various parasites are actively working to reduce the number of these voracious scoundrels.
Recommended:
We Fight The Beet Stalk Weevil
The beet stalk weevil lives everywhere and loves to feast on sugar beets, as well as numerous weeds from the amaranth and haze families. As a result of the harmful activity of these garden gourmets, the leaves of the cultivated crops dry up and flower stalks break off, which in turn leads to a noticeable deterioration in the quality of seeds, as well as to a significant decrease in yield. Also, the sugar content and weight of both mother and factory beets are significantly reduced
Gluttonous Redcurrant Aphid
Redcurrant aphids live almost everywhere and, in addition to red currants, they also damage black and white. Sometimes roses and gooseberries also suffer from her attacks. Particularly severe damage can be seen towards the end of July. The tissues damaged by parasites grow strongly, and the leaf blades protrude noticeably, and the appearance of swelling is noted on them. For a year, the harmful red currant aphid is capable of producing several generations (mainly four to five), which has a very negative effect
Gluttonous Rice Weevil
The rice weevil is a harmful insect that was first accidentally discovered in distant India. But now it can be found literally everywhere, however, on the territory of the Russian Federation, this pest inhabits mainly the southern regions. Despite the fact that the weevil is still rice, it also attacks crops such as corn with wheat, rye with barley, buckwheat with hemp seed, as well as barley with millet, beans, etc
Getting Rid Of The Beet Weevil
The beetroot, or beet, weevil is a big lover of beets and weeds from the notorious Haze family. And although only one generation of this pest develops per year, its larvae and beetles can cause very serious damage to the beet crop. Numerous ulcers on the roots gnawed out by harmful larvae lead to a decrease in the sugar content of delicious root crops and their mass. And the bugs gnaw through young sprouts and devour the cotyledonous leaves along with the real ones, which way
Gluttonous Gray Bristly Weevil
The gray bristly weevil most often lives in the forest-steppe zone, and a little less often it can be found in the steppe. This pest damages mainly perennial and year-old legumes: lentils with beans and clover, as well as sainfoin and sweet clover with peas. He will not refuse to feast on alfalfa with lupine, as well as some other wild legumes. Attacks of gray bristly weevils often lead to the complete destruction of leaves on the stairs of a huge number of beans
