Agrometeorological forecast for the month of September

During most days of the first ten-day period of September, agrometeorological conditions will be determined by unstable weather with precipitation, which will improve moisture reserves in the upper soil layers – a prerequisite for quality pre-sowing tillage of the areas intended for sowing with winter rapeseed, a crop requiring precise agrotechnology. The widespread rainfall at the end of August was late for part of the late field crops, which, as a result of the soil moisture deficit, completed their development prematurely.

At the beginning of September, the final stages of development of the late maize hybrids that have overcome the negative effects of the deepened summer drought will proceed at temperatures around and below the climatic norms. During the first ten-day period, the medium-late hybrids will enter the wax ripeness and full ripeness stages. In the late hybrids, the milk ripeness and transition to wax ripeness stages will take place. The forecast frequent precipitation during the ten-day period will increase the risk of development of certain fungal diseases – grey mould on the ripening grape yield, and late brown rot on the fruits of fruit trees.

During the second ten-day period, the agrometeorological conditions will undergo a change. The expected sunny and warm weather during most days of the ten-day period will favour the synthesis and accumulation of more sugars in the fruits of the autumn varieties of fruit trees. By mid-September, the late maize hybrids will complete their development, and in rice, wax ripeness and full ripeness will be observed.

During this period, significant precipitation is not forecast and the conditions will be suitable for clearing the areas from sunflower and the earlier maize hybrids, and for carrying out the sowing of winter rapeseed.

The conditions will be suitable for performing seasonal soil tillage – deep ploughing, pre-sowing tillage of the fields intended for sowing with winter rapeseed and winter cereal crops. The period is suitable for the preparation of wheat and barley seed intended for autumn sowing – disinfection and treatment of the seed material against seed-borne phytopathogens, common and loose smut, septoria leaf blotch and fusarium diseases.

During the third ten-day period of September, the transitional changes in agrometeorological conditions typical for the end of summer and the beginning of autumn will be observed, with lower minimum temperatures. In the second half of the ten-day period, ground frosts are expected in the higher fields, which must be taken into account when harvesting vegetable crops susceptible to frost (tomatoes, peppers).

The forecast precipitation at the beginning of autumn will provide moisture for the normal progress of the initial stages of vegetation of winter rapeseed. At the end of September, in part of the crops sown within the agrotechnical timeframe, the emergence stage will be observed. In the emergence stage, damage to rapeseed is caused by the cabbage stem flea beetle (adult individuals) and the turnip sawfly (false caterpillars), which requires monitoring of the emerged crops and, when pest density exceeds the economic injury level (EIL for the cabbage stem flea beetle – 2 beetles per m²; EIL for the turnip sawfly – 2–3 false caterpillars per m²), timely treatment.

Source: NIMH