Cotton bollworm (Helicoverpa armigera Hbn.): features of development, distribution and harmfulness

Abstract

The article presents the results of a scientific work, where for the first time a long-term forecast of a
"phytophagous plant" was carried out, which is a rather important measure in the protection of black currant. During
the experiment, attention was paid to weather conditions, since this important factor was involved in the construction
of a logistic forecasting model. An important task of our scientific work was to find a period of biological
development of a migrating phytophagous larva, where the use of complex preparations would be economically
beneficial. A bud damaged by a currant bud mite differs from a normal bud in that it resembles a cracked cabbage
head. This happens due to the nutrition of the phytophagus with cell juice. The tick's salivary enzyme enhances the
growth and development of cells, so the bud changes due to this phenomenon. The buds are damaged by the currant
bud mite, do not bloom, gradually dry up, rot and fall off. According to our prediction, the model of the exit of the
migrating larva was clearly calculated according to the regression equation, which coincides with the end of the
fourth and the transition to the fifth phenophase of blackcurrant development, that is, befor No less important in the
protection system is the spraying process, if it is carried out with an ordinary mounted sprayer, then in fact the upper
part of the leaf surface is treated, the larva of the currant bud mite is in the middle and lower tiers of the bush, which
is practically unaffected by the drug. Therefore, we developed the modernization of the OP – 2000 boom sprayer,
and created (SRS) a specialized rolling stock that ensures the flexibility of the system and maneuverability and
primarily serves the optimality of zones, taking into account the lower, middle and upper tiers of the blackcurrant
bush.e flowering. It is important to note the arc brackets with the original design of the nozzles, which determine the
geometry of the optimal dispersion spraying zones. Such brackets have an arc-shaped design and are installed on
two sides of the sprayer. When the specialized unit moves, the upper nozzle provides optimal spraying of the upper
zone, the middle nozzle - the middle part, and the lower nozzle – the lower tier of the blackcurrant bush, where the
main population of the phytophagous is located. Thanks to the side nozzles, the sprayer creates a fog-like finedispersed
environment, which directly ensures the treatment of the row spacing in one pass of the unit and reduces
the use of chemicals four times.