Latest Wheat Field Management Techniques and Methods Tutorial
Emergence and Tillering Stage
1. Growth Characteristics
The emergence and tillering stage runs from sowing and emergence to jointing.
(1) Spring wheat, from emergence to jointing, enters the young ear elongation stage with 4 leaves.
(2) Semi-winter wheat, from emergence to jointing, enters the young ear elongation stage with 5 leaves.
(3) Winter wheat, from emergence to jointing, enters the young ear elongation stage with 7-8 leaves.
2. Cultivation Characteristics
(1) Ensure uniform and strong seedlings.
(2) Strive for early tillering and early root development.
(3) Achieve strong seedlings for overwintering.
(4) Accumulate more nutrients, which helps safe overwintering and lays the foundation for increased yield.
3. Management Measures
(1) Seedling fertilizer: After uniform emergence, apply a quick-acting fertilizer once to promote seedling growth and earlier tillering; generally apply 5-8 jin of urea per mu.
(2) Tillering fertilizer: The amount of tillering fertilizer must not be too much, to prevent excessive growth before winter and reduced cold resistance; generally apply 8-10 jin of urea per mu.
(3) Winter fertilizer: After the Winter Solstice, generally apply 2000 jin of organic fertilizer to consolidate pre-winter tillering and promote young ear differentiation.
(4) Chemical weed control: From after sowing to before emergence, spray with 200-300 grams of 25% chlorotoluron wettable powder mixed with 120 jin of water; spraying during rainy periods is best.
(5) Rolling wheat: Rolling is generally carried out during the overwintering period; roll strong and excessively vigorous seedlings to control top growth and promote bottom growth, shorten the length of the first and second internodes at the stem base, increase thickness, and improve lodging resistance.
(6) Preventing freeze damage: The main measures to prevent freeze damage include selecting varieties with strong cold resistance, sowing at the right time, cultivating strong seedlings, and watering before cold waves to reduce freeze damage.
Jointing and Booting Stage
1. Growth Characteristics
The jointing and booting stage includes growth periods such as jointing, booting, and heading; it is a period when vegetative growth and reproductive growth proceed together. When early spring temperatures rise above 10°C, wheat begins jointing; tillers produced after jointing are generally ineffective tillers. After booting is the period when florets differentiate and some degenerate. During the jointing stage, stem and leaf growth predominates; during the booting stage, stem and ear growth predominates.
2. Topdressing
(1) Jointing stage: Generally apply about 15 jin of urea per mu to increase grain number and grain weight and prevent premature senescence.
(2) Booting stage: Generally apply 5-6 jin of urea per mu to increase nutrient supply to the ear and promote reproductive organ development.
3. Clearing Ditches and Drainage
From late February to early March, wheat begins jointing; in March, rainfall gradually increases, causing various wheat diseases. Wheat fields should be cleared of ditch blockages and drained to lower the water level and reduce disease.
4. Preventing Lodging
(1) Use short-stalk varieties.
(2) Apply fertilizer and water reasonably.
(3) Control excessive growth; when wheat grows excessively, chlormequat can be used for control.
Heading and Maturity Stage
1. Growth Characteristics
This stage refers to the reproductive growth period after wheat heading. Wheat in the middle and lower reaches of the Yangtze River heads around mid-April, and the heading period lasts about 40 days. This stage is the period of wheat grain formation and is also the key period determining wheat grain number.
2. Reasonable Irrigation and Drainage
After wheat heading, physiological water demand increases, and this is the peak water demand in the wheat life cycle. Generally, a soil moisture content equivalent to about 70% of field maximum water-holding capacity is suitable. Southern regions have more rain in April and May, so attention should be paid to clearing ditches and drainage, ensuring surface water can drain and subsurface water can seep away.
3. Disease and Pest Control: In the late growth stage of wheat, there are armyworms, aphids, Fusarium head blight, powdery mildew, and rust damage.
(1) Pests: Insecticide pesticides can be used for control.
(2) Diseases: First, the control of Fusarium head blight. A mixed agent of carbendazim and trichlorfon can be used. It also controls powdery mildew. Second, the control of rust. Sodium rust-remover or rust-removing acid can be used, diluted 200 times, with 2 liang of washing powder added for control.