Common problems after sowing wheat and how to solve them

◇What to do if the wheat variety is chosen improperly?

Sowing spring-type and weakly winter-type varieties on medium and early stubble fields will cause the wheat seedlings to grow excessively before winter, which is not conducive to safe overwintering.

Countermeasures: On the basis of early hoeing and pressing, earth up around the roots before winter, or apply “mengtou manure” to protect the wheat seedlings for safe overwintering.

◇What to do if wheat is sown too early?

If wheat is sown too early, after the seedlings emerge the leaves are narrow and long and drooping, with insufficient tillering, and the main stem and part of the large tillers enter the double-ridge stage of young ear differentiation before winter; in winter, when encountering a low temperature of -10℃ lasting about 5 hours, freezing damage will occur. Countermeasures: Press at the appropriate time to inhibit the growth of the main stem and large tillers; after pressing, hoe promptly, and in combination with watering, apply 15 kg of ammonium bicarbonate per mu; if necessary, spray the leaves with a 0.2-0.3% chlormequat solution to control excessive growth and resist freezing damage.

◇What to do if wheat is sown too late?

Because the growth period before winter is short and accumulated temperature is insufficient, the wheat seedlings grow thin and weak with few tillers. Countermeasures: Focus on hoeing and supplementing fertilizer and water, and apply 10-15 kg of ammonium bicarbonate per mu at the three-leaf stage; for wheat fields with poor soil moisture and rapid water infiltration, irrigate tillering water promptly after the three-leaf stage (but for plots with suitable moisture or heavy clay soil and poor water permeability, it is not suitable to water before winter); for the last hoeing before freezing, pay attention to earthing up around the roots to protect the seedlings for safe overwintering.

◇What to do if wheat is sown too shallow?

The suitable sowing depth for wheat is 3-5 cm. If sown too shallow (less than 3 cm), the wheat seedlings grow prostrate, the tillering nodes are exposed, there are many but small tillers, and they are not drought-tolerant, prone to freezing and premature aging.

Countermeasures: Press several times promptly before emergence, and after emergence, combine hoeing with earthing up around the roots; if necessary, during the overwintering period use outside soil cover or apply “mengtou manure” to prevent freezing damage during overwintering.

◇What to do if wheat is sown too deep?

If wheat is sown too deep (more than 5 cm), emergence is slow, the leaves are slender, there are few and small tillers, secondary roots are few and weak, and the wheat seedlings are yellow and thin.

Countermeasures: Promptly remove soil to expose the seedlings. The method is: use a bamboo rake or iron rake, starting from the center of the border surface, rake horizontally along the rows; when clearing the last row, drag all the remaining soil onto the border ridge; for wheat sown at the appropriate time, clearing the seedlings before winter generally starts from the two-leaf stage and ends at “Minor Snow”.

◇What to do if the sowing rate is too high?

This shows as crowded wheat seedling growth, yellow, thin, and weak plants, poor individual development, and very few tillers.

Countermeasures: First thin the seedlings promptly, especially the “clumped seedlings” at field ends, field edges, and within the field; thin early and thin heavily to establish a suitable population structure and promote individual development; then, in combination with watering, apply a small amount of quick-acting nitrogen and phosphorus fertilizer to make up for the excessive consumption of soil nutrients.

◇What to do if too much basal fertilizer is applied?

If too much basal fertilizer is applied, after the wheat seedlings emerge they grow excessively, with many tillers, wide and large leaves, and severe field shading.

Countermeasures: When the main stem of the wheat seedlings has grown 5 leaves, deep hoe 5-7 cm between the wheat rows to cut part of the secondary roots, control nutrient absorption, reduce tillering, and cultivate strong seedlings.

◇What to do if soil moisture is insufficient after sowing?

This shows as difficulty in seedling emergence, or after emergence slow tiller formation, grayish-green leaf color, short and small central leaves, slow or stagnant growth (commonly known as “shrunken-heart seedlings”), basal leaves gradually turning yellow and dry, and few and fine roots.

Countermeasures: After sowing, check soil moisture promptly; for plots where insufficient moisture or drying out affects emergence, irrigate with a small amount of water if irrigation conditions are available, and if not, press 1-2 times promptly.

◇What to do if the soil is too wet after sowing?

After the wheat seedlings emerge, the leaf color is pale yellow, tiller formation is slow, and in severe cases the leaf tips turn white and dry up.

Countermeasures: Promptly perform deep intertillage to disperse moisture and aerate, and apply a small amount of quick-acting fertilizer to promote early seedling growth.

◇What to do if emergence is incomplete after sowing?

After sowing wheat, check emergence promptly, and once missing seedlings are found, promptly fill them in. The methods are: 1. Resowing. Choose the same variety as the plot with missing seedlings, first soak the seed and germinate it under suitable temperature conditions, or soak it for 12 hours in a 25,000-fold naphthaleneacetic acid solution or a 500-fold potassium dihydrogen phosphate solution, then sow to facilitate emergence and growth; 2. Transplanting. For plots where there is not enough time for resowing and where missing seedlings remain after resowing, transplant seedlings on the spot during the wheat tillering stage. The transplanted wheat seedlings should be strong seedlings with 1-3 tillers, and the transplanting depth should be such that “the heart is not buried above and the white is not exposed below”; the transplanting time should be no later than “Minor Snow” to facilitate seedling recovery and overwintering.