What are the methods for treating sunflower seeds before sowing?

  Sunflower seed coating is the process of evenly coating the seed surface with a seed-coating agent containing a certain proportion of various components such as insecticides, fungicides, trace nutrient elements, plant growth regulators, slow-release agents and film-forming agents, forming a firm medicinal film. As the seeds germinate, sprout, emerge and grow, the active ingredients in the coating are gradually released and absorbed by the plant roots, then transported to all parts of the seedling, giving the seedling good preventive and control effects against pathogens and pests.

  1. Functions of the coating agent

  (1) It can promote the growth and development of sunflower plants: seeds treated with the seed-coating agent effectively control seedling-stage diseases and pests of sunflower, emerge quickly, and the seedling survival rate can reach 95%. The seedlings grow vigorously with well-developed root systems, thus achieving uniform and strong seedlings, promoting sunflower growth and development, and increasing sunflower yield.

  (2) It can reduce environmental pollution: using seed coating changes the seedling-stage pesticide application method from open spraying to concealed application. Generally, no spraying is needed for pest control within 40-50 days after sowing. This delays the timing of pesticide spraying, reduces the number of sprayings and the amount of pesticide used, thereby avoiding air pollution and reducing the chance of human and livestock poisoning.

  (3) It saves seeds and pesticide and lowers costs: coated seeds are of good quality, allowing precision sowing and changing the traditional habit of heavy sowing in agriculture. The seeding rate can generally be 1/3 of the conventional rate. The number of pesticide applications is relatively reduced, which can also ease the shortage of labor during the busy farming season.

  2. Coating methods

  When coating seeds, the seeds must be carefully selected and the seed moisture content strictly controlled. For large quantities of seeds, a seed coating machine should be used for coating. If no coating machine is available or the seed quantity is not large, manual coating methods can be used.

  (1) Large bottle coating method: weigh a certain amount of seeds and put them into a large bottle, generally filling at most 1/2 of the bottle's space, then add the seed-coating agent in proportion, seal the lid, and shake quickly until the agent evenly adheres to the seed surface. Pour out and dry in the shade.

  (2) Plastic bag method: use a large plastic bag of good quality, weigh a certain amount of seeds and seed-coating agent and pour them into the bag, tie the bag opening tightly, and two people quickly turn it over until the agent is evenly mixed and coated on the seed surface. Pour out and dry in the shade for later use.

  (3) Pot or basin coating method: first fix the pot or basin in place, weigh the seeds and seed-coating agent in proportion and pour them into the pot or basin, quickly stir with a wooden shovel, and after even mixing, take them out and dry in the shade for later use.

  Sowing at the right time is a key technical measure for effectively using soil moisture and ensuring normal crop maturity, and it is especially important for arid and semi-arid regions.

  1. Selecting good varieties

  Good varieties are one of the important factors in increasing crop yield per unit area. Excellent edible-type sunflower varieties suitable for cultivation in the region, with characteristics such as high quality, high yield and strong stress resistance, can increase yield by 18.1-32.5% compared with other varieties, and have plump grains and pure color.

  2. Seed treatment

  (1) Germination test

  Conduct a germination test 7-10 days before sowing to determine the seeding rate.

  (2) Sun-drying seeds

  Sun-dry the seeds for 2-3 days before sowing to reduce moisture, enhance the air permeability of the seed coat, strengthen the activity of enzymes in the seeds, increase the germination rate, and achieve rapid germination and uniform emergence.

  3. Seed soaking and germination acceleration

  Seed soaking and germination acceleration can shorten the time for seeds to absorb water and swell after sowing, promote early emergence, reduce the harm of soil pathogens, and achieve uniform and strong seedlings. Seed soaking: soak the seeds in warm water at 20-25°C for 10-12 hours, then remove and drain the water. When soil available zinc is less than 0.5 mg/kg, soak the seeds in a 20-fold zinc treasure solution; after soaking, remove the seeds and place them indoors at 18-22°C, cover with a soaked hemp sack, and after 24 hours they will begin to show white sprouts. Air-dry the sprouts for 3-4 hours before sowing. Through the above seed treatment, full stands can be ensured, seeds can be saved, and emergence can be 1-3 days earlier.