Nustatyti BotaniGard efektyvumą grambuolių lervų daromai žalai

Abstract

There are two main species of cockchafers found in Lithuania: the common (melolontha melolontha) and the forest (Melolontha hippocastani) cockchafers. They cause the biggest damage right after the second hatching of the grub, which happens in the third year of their existence. They keep on growing on an enormous rate when they find a great amounts of nutritious plant roots full of carbohydrates and low on nitrogen substances. They like the roots of birches and pines the most. Once they are finally hatched, they need a great amount of nitrogen, which can be easily found in the leaves of oak and birch trees. A combination of grubs feasting on pine roots, and grown up bugs eating the leaves of an oak tree is very beneficial for the upcoming cockchafer generations for years to come. Cockchafer grubs harm many agricultural cultures. They do consume potatoes and make them useless for human consumption or even animal feed. Grown ups consume the leaves of apple, plum, cherry, grape, gooseberry trees. Although grubs are still the ones who cause the most damage by destroying the roots of the young plants such as hops, watermelons, potatoes, sugar beets, garlics, buckwheats, grains, flaxes, cabbages, melons, mints, carrots, canolas, sunflowers, onions, sages or wild strawberries. The damage done by cockchafers can be reduced by staining the seeds or coating the roots of the plants by a mixture of water, clay and insecticides just before planting. In some European countries the preparation with 10% of carbosulfan is used, called "Marshal suSCon". Grown up cockchafers can be cleared away with the help of insecticides or by shaking them out from the trees early in the morning. When grubs are turning into pupas, the soil requires some special treatment. Acidic soil requires liming, and light soil requires fertilization. Growth rate in infertile soil can be improved by fitomeliotation – growing lupins.