What are sunflower planting techniques? How to prevent disease?

Sunflowers are not only beautiful flowers, but also have edible value, the fruit can be used as oil, the economic benefit of planting is very high. So what are the sunflower planting techniques? How to prevent and cure the disease?

First, what are the sunflower planting techniques?

1. Land selection and preparation

Selecting a good plot when planting is an important factor to increase yield and income. Sunflower can adapt to soil widely, can adapt to heavy clay to light sandy soil, and must be resistant to acid and alkali. Generally, the acidity and alkalinity is between 5.5 and 8.5. The larger acidity and basicity has a certain effect on its growth. If the soil layer is deep and the terrain is flat, we must also require a rotation period of more than 4 years, fine soil preparation, deep turning of the soil, breaking the soil, removing stones and other hard objects, and then applying sufficient base fertilizer.

2. Seed selection treatment

The seeds with good varieties, fast growth, high yield, stress resistance and disease resistance must be selected, and the seeds with full grains, shape, size and color must be selected, while those with poor quality should be eliminated. Before sowing, the seeds should be treated to improve the germination rate, first put the selected seeds in the sun for 2-3 days, and remember to turn them in time when drying the seeds. Soak the seeds with 150ml of 40% zinc parathion and 5-7.5kg in water to eliminate the germs on the surface of the seeds and prevent the occurrence of diseases.

3. Sowing seeds

The sowing time depends on the local climate and soil. Generally, the sowing time is between April and May. Hole sowing and trenching on demand can be used as sowing methods, generally dominated by hole sowing. General hole depth is 5-6cm, sowing rate is 1-1.5kg per mu, sowing 4-5 seeds per hole, wide and narrow row sowing, large row spacing is 1 meter, while small row spacing is 60cm, plant spacing is 60cm. After seedling emergence, it is best to keep about 1400 seedlings per mu according to the actual situation of seedling emergence.

4. field management in the later stage.

The field management in the later stage mainly includes mid-tillage weeding, fertilizer and water management and auxiliary pollination. Intertillage and weeding should be carried out 2-3 times a year to ensure strong planting growth, the first time can be carried out between seedlings, intertillage 3-4cm, topdressing the right amount of urea, the second time in a week, when deep ploughing 8-10cm, the third time at the end of the plate, deep ploughing 3-4cm, topdressing fertilizer. Artificial pollination of sunflower is very important. It is a cross-pollinated crop. Artificial pollination of sunflower can increase seed setting rate, yield and income. The specific method is: put on gloves, after 2-3 days of blooming, touch them one by one, artificial pollination is best in the morning or evening, to avoid the high temperature period at noon.

2. Control methods of sunflower diseases

1. Sclerotinia disease

Sclerotinia sclerotiorum is caused by Sclerotinia sclerotiorum, which often occurs in the period of low temperature and rain in spring. brown disease spots appear on the stems or leaves of sunflowers during the disease. With the development of the disease, the brown disease spots gradually spread to other parts. Finally, concentric rims are formed at the disease spots. In the moist environment, white hyphae and brown sclerotia appeared in the diseased spot. When the disease was serious, the plant withered, the diseased tissue decayed and easily broken, and there were black sclerotia inside.

Prevention and control methods: the main cause of Sclerotinia sclerotiorum disease is that the pathogen lurks through the winter in the soil or disease remains and seeds, and when the temperature rises in the coming year, it begins to reproduce in large numbers, spread by the wind, and finally invade the sunflower. Therefore, these measures should be taken during planting, such as deep disinfection of soil, centralized burning of diseased remains, disinfection and sterilization of seeds, reduction of pathogens, application of phosphorus and potassium fertilizer during planting, and increase plant disease resistance. when the disease occurs, it is treated with methyl thiophanate, Pythium wettable powder and other agents.

2. Verticillium wilt

Verticillium wilt mainly harms the adult sunflower, which mostly occurs in low-lying land and when the planting density is high, the leaf tip begins to fade when the disease occurs, then the whole leaf fades, and the leaves turn brown after yellowing. With the development of the disease, the seriously diseased plant leaves gradually withered and died, and white mildew appeared on the leaves in the environment of air humidity.

Control methods: similar to Sclerotinia sclerotiorum, pathogens overwinter in soil, disease remains and seeds, invading from wounds or young roots after sowing, and preventive measures are the same as Sclerotinia sclerotiorum. It is found that the diseased plant should be cleared out of the field and burned in time, the disease hole should be disinfected, and if necessary, the root should be irrigated with 400 times of 20% verapamil EC, and the effect is good.

3. Rust

During the epidemic period, the fungal disease caused by sunflower rust can lead to a serious reduction in sunflower production, leaves, petioles, stems and sunflower plates can be infected, and a small number of spores pile up at the site of the disease, with the development of the disease, brown powder appears after spore rupture, resulting in black powder in the later stage, resulting in plant death.

Prevention and control methods: pathogens spend winter or summer on soil, diseased bodies and seeds, so preventive measures are similar to the former two, select varieties with strong disease resistance, strengthen management during planting, increase phosphorus and potassium fertilizer, increase disease resistance, and burn diseased plants out of the field when they occur, and spray 15% triadimefon wettable powder 1000-1500 times or 50% triadimefon EC 800 times.