Pests of vegetables: onion thrips, Common Mole Cricket, cabbage aphid. Characterization, control measures. Onion thrips. A very small insect length of 1 – 1,5 mm. Hibernates under the fallen leaves, litter and soil. Development of thrips from egg to adult stage takes place over 20-25 days. During the year, is 6.8 generations. The biggest spread of the pest is observed in July.
In September, thrips go into winter quarters. During the growing season thrips damage the leaves of onion. They appear whitish-silver stain. If a strong leaf damage bend, turn yellow and dry up, plants are stunted. The surface of these bulbs under dry scales becomes sticky, reticulate-wrinkled, with light silvery spots.
On leaves of cucumber at the injection site formed light-yellow spots. If a strong injury leaves turn brown and wither,. Control measures. Removal of post-harvest residues, weeds, disinfecting greenhouses immediately after harvest of crop residues with sulfur dioxide (100 g of sulfur per 1 m3), sprayings karbofosom (0,2%) every 7 – 10 days. Common Mole Cricket. Damages cabbage, cucumbers, tomatoes, eggplant, onions, lettuce and other plants. Paving in the land of horizontal moves, Mole Cricket and its larvae gnaw the roots and stems of plants and sown seeds. In the soil at a depth of 10-15 cm arranges earthen cave (female) with thick walls, which lays from 100 to 440 eggs. After 10-17 days of egg larvae, and the first time they live in the nest, and then go out and crawl. When growing seedlings in greenhouses, creating favorable conditions for breeding chirruping. Particularly strong pest inhabits areas where the spread manure without first destroying the weeds. Control measures. In the greenhouses in the spring prior to seeding or transplanting against chirruping use poison baits from grains of corn, wheat, barley or other grains mixed with zinc phosphide, as well as grain and hexachloran (50 g / kg on dry grain). Bait is spread evenly along the bottom of the pit during the printing hotbeds. A few days before sowing seeds in the surface layer of greenhouse mixture to a depth of 2-3 cm is made freshly cooked grain at the rate of 40-50 g per frame, or along parubney arrange grooves in the sand are poured with kerosene. For catching chirruping recommended on highly contaminated sites in the autumn digging pits or groove depth of 40-50 cm, and fill them with horse manure. In the winter chirruping climb into the pits. Late in autumn they dig up, manure scatter and destroy medvedok. Cabbage aphid. Eggs overwinter on weeds and stump sprouts. Aphids reproduce very rapidly. Development of one generation lasts 10-14 days. The plants form colonies of aphids, which usually occupy the top of plants, stems, buds and leaves from the top and bottom sides. Leaves are covered with waxy excretions, medoobraznoy fluid and remnants of skin after molting aphids, discolored, and sometimes take a pink color, curl. During the growing season aphid has several, sometimes up to 15 generations. In the autumn the females lay eggs of both sexes. Control measures. In the vegetation period when an individual colonies of aphids conduct spraying 0,1-0,2%-s fosfamidom (rogor, BI-58), sayfosom (0,2%), karbofosom (0,4%). To attract hover flies, whose larvae consume the pest, the cabbage should be near the fields to sow dill.