Methods to control excessive growth and promote sturdy wheat seedlings: these technical points must be mastered

When wheat seedlings grow excessively before winter, their growth period advances, nutrient accumulation decreases, and cold resistance drops, which is not conducive to safe overwintering. They can be managed by category according to the cause of excessive growth to control vigorous growth and promote sturdiness.

1. Vigorous seedlings formed by too-early sowing

The seedling leaves are slender, tillering is insufficient, and the main stem and some large tillers enter the double-ridge stage before winter. Such wheat seedlings are often vigorous early and weak later, and will be frostbitten in winter when exposed to a low temperature of minus 10°C lasting 5 hours. They should be pressed in a timely manner to inhibit the growth of the main stem and large tillers of the wheat seedlings and control spindly growth. Pressing should be done on a sunny morning; it must not be done when there is frost or dew has not dried, so as not to injure the seedlings. After pressing, loosen the soil with a hoe and water with winter water in a timely manner, and apply 15 kg of ammonium bicarbonate per mu. If necessary, spray once with a 0.2-0.3% chlormequat solution to inhibit excessive growth and prevent freeze injury.

2. Vigorous seedlings formed by too-large sowing rate

The seedlings grow crowded, individual development is poor, and tillering is few, so thinning should be done in a timely manner, with fertilizer and water supplemented. Thinning can establish a suitable population structure and promote individual development. Combine thinning with watering to supplement an appropriate amount of quick-acting nitrogen fertilizer and phosphate fertilizer.

3. Vigorous seedlings formed by excessive fertilizer and water

The wheat seedlings have many tillers, broad leaves, and severe field closure. Deep hoeing should be used to cut roots, hoeing 5-7 cm deep between the rows of the wheat field to cut some secondary roots, control nutrient absorption, inhibit tiller occurrence, and cultivate sturdy seedlings.

4. Vigorous seedlings formed by improper variety selection

Sowing spring wheat and weak-spring wheat @#@245@#@ varieties too early will lead to excessive growth before winter and make them prone to freeze injury, so soil should be mounded and manure covered. On the basis of hoeing and pressing, cultivate soil around the roots before winter and apply organic fertilizer to protect the wheat seedlings for safe overwintering.