2025
The flag leaf in wheat determines 43% of the yield, affecting the formation of the grain. In this phase the colonisation of the crops by the causative agents of tan spot, septoria and powdery mildew occurs. And therefore the agronomist's task is to preserve the functioning period of the flag leaf.
"The longer the flag leaf retains its green appearance, the better filled the grain will be and the greatest possible amount of the grain itself will be formed. However, at this moment colonisation by such diseases as: tan spot, septoria, and also in dense crops powdery mildew may be observed occurs. They can destroy from 5 to 70% of the harvest," he emphasised.
The specialist recalled that septoria develops over a wide range of temperatures (from 9 to 30 °C) and in the presence of droplet moisture. Tan spot is mainly observed in the southern regions of Ukraine, where dry weather conditions favourable for its development predominate. And for the development of powdery mildew increased humidity and stably moderate warmth are needed.
For effective protection of the flag leaf, Serhii Korniushenko recommends applying the fungicides:
- Split (difenoconazole, 250 g/l);
- Paracelsus (flutriafol, 250 g/l);
- Dot (cyproconazole, 80 g/l + propiconazole, 250 g/l);
- Stark (azoxystrobin, 250 g/l);
- Salto (thiophanate-methyl, 500 g/l);
- Mecenat (propiconazole, 250 g/l).
He recommends combining these products in the presence of one or another disease.
