Pay attention to prevent winter wheat

"Small old seedlings" is a phenomenon in which the emergence, rooting, and tillering of seedlings are slow and delayed due to various reasons. This kind of wheat seedlings is called "small old seedlings" in the north and "frozen seedlings" in the south. The main causes of "small old seedlings" and "frozen seedlings" are soil compaction, poor soil permeability, poor soil preparation, thin soil layers, deep sowing, poor soil fertility or severe lack of phosphate fertilizer.

In the middle and lower reaches of the Yangtze River, during the autumn sowing, the rains and rains are continuous, the soil compaction and poor air permeability, and the formation of yellow roots, red leaves, and single-stalk "frozen seedlings". This kind of wheat field should strengthen drainage, loosen the soil, increase the temperature and promote the root; replenish the phosphate fertilizer, promote the roots and promote the seedlings.

In the northern winter wheat area, “small old seedlings” mainly occur in poorly drained, low-lying, saline-alkali land and rice paddy fields. The common problem in these areas is high groundwater level, wet soil plate, poor permeability, low temperature in early spring, slow release of available nitrogen and phosphorus nutrients; some plots are due to salt-reducing roots. For such wheat fields, the drainage system should be improved, the groundwater level should be lowered, and soil should be loosened during the period of growth to improve soil permeability.

In autumn, soil drought and de-fertilization can also form “small old seedlings”. Watering should be combined with this type of wheat field, and nitrogen and phosphate fertilizers should be applied to make it grow faster.

Late sowing wheat, the seedlings are small before winter and the secondary roots are few. If the frozen water is late and the plough layer is frozen and the water is too much, the returning to the sap and the surface ventilation will deteriorate, affecting the birth of the secondary roots, and it is easy to form a "small old seedling". For this kind of wheat field, it should be ventilated in the early spring to promote hair roots. In addition, in all kinds of soils, due to the deep sowing, the seedlings are weak and the "small old seedlings" are delayed, which is even worse in late sowing wheat.

It can be seen from the above that there are many reasons for the "small seedlings" and "sudden seedlings". When remedial measures are taken, the symptoms should be solved for the reasons. (He Yongmei)