The regional branch of the Rosselkhozcenter draws the attention of farmers of the Rostov region to the spring increase in the number of winter grain mites on winter crops.
After a mild winter with the onset of stable heat, an increase in the population of a dangerous pest of winter crops is predicted. Particular attention should be paid to areas favorable for the habitat and reproduction of this pest: with a glut of crop rotation with winter cereal crops, an increase in the number of winter wheat carrion in the fields, areas with zero tillage technology, and the accumulation of crop residues. Grain mites damage plants and are carriers of viral diseases and can reduce yields by up to 50%.
For the most effective pest control, specialists of the regional Rosselkhozcenter recommend taking into account its biological characteristics.
– The dispersal of the winter grain mite occurs in the phase of eggs with soil or plant debris; at the beginning of winter, the 1st generation develops. Females of this generation lay winter eggs, from which larvae hatch, giving rise to the development of the 2nd generation. In March-April, females of this generation lay summer eggs until late autumn. The first sign of the presence of a pest is grayish blurry spots on the leaves. The tick breaks the epidermis of the leaves and feeds on cell sap. Heavily damaged crops acquire a silvery-gray color, the ends of the leaves dry out and curl. Plants are strongly oppressed, especially with a lack of moisture, – explains the deputy head of the branch of the Federal State Budgetary Institution “Rossselkhoztsentr” in the Rostov region Natalya Shmeleva.
The manifestation of harmfulness is predicted in March-April with the onset of stable heat, but it is impossible to predict the places of occurrence of the winter grain mite with accuracy. The tick is located locally on the field, these can be large spots that are not visible from the road, so you can only find them by walking across the field. First of all, it is necessary to examine the crops of winter crops for ear predecessors. Noticeable spots on crops should attract special attention so as not to confuse mite colonization with winter damage, recurrent frosts, root gils and prevent large crop losses.
“Therefore, it is important to correctly and timely study visible damage to crops. To do this, we recommend regularly sampling plants from a row along with soil 10/6 cm wide. With a soil sampling depth of up to 10 cm, the tick gets into the sample in any case, regardless of the time of day. We recommend taking at least 50 samples per 100 ha, labeling and packing each one in a separate bag. Samples are placed in a plastic container and filled with water, the tick floats up and can be easily counted, or the samples are disassembled under a table lamp with a magnifying glass,” says Natalya Shmeleva.
The economic threshold of harmfulness is 5 individuals per 1 leaf of red-legged ticks. For night treatments, the pyrethroid group is sufficient; for daytime treatments, another systemic drug (dimethoate, imidocloprid,) should be added to the tank mixture. The introduction of chemical pesticides is preferably carried out in a tank mixture with microbiological and organomineral fertilizers based on humic acids, which allow crops to overcome the negative effects of pesticide stress, neutralize the toxic and mutagenic effects of pesticides. In the spring, the fight against ticks can be combined with top dressing.
Full version on the website On increasing the effectiveness of the fight against grain mites
