How to plant the latest watermelon seeds?

Watermelon, also known as summer melon, cold melon, etc., is an annual trailing vine of watermelon of Cucurbitaceae. Its original species may come from Africa and has been widely cultivated in tropical to temperate zones all over the world. There are many varieties in China. Xinjiang, Lanzhou in Gansu, Dezhou in Shandong, Liyang in Jiangsu and other places are the most famous. Let's take a look at how to plant watermelon seeds.

Seed selection

Watermelon seeds should be carefully selected according to the characteristics of each variety before sowing, and blighted seeds, moth-eaten, damaged, moldy seeds and other sundries should be removed. Then sun 1 to 2 noon, thickness not more than 1 cm, turn every 2 hours or so, so that it is evenly exposed to light, in order to enhance seed vigor, improve germination energy and germination rate. The germination test should be done before sowing, and the sowing amount should be determined according to the seed germination rate. The general seed requirement for direct broadcast is 50g / mu and 80g / mu.

Disinfection and sterilization

1. Seed soaking in warm soup: seed soaking in warm soup can prevent watermelon mosaic virus disease. 3-4 days before sowing, put the selected watermelon seeds in an earthen pot and soak the seeds in warm water with 2 parts of boiled water and 1 part of cold water for about 55 ℃. The seeds should be stirred continuously after the water temperature dropped to 30 ℃, soaked in heat for 3 hours and 5 hours, and then washed away the mucus from the seed coat.

2. High temperature blanching: high temperature blanching can kill the pathogens on the seed surface. The two containers are filled with the same amount of cold water and boiled water respectively, the amount of water is 3 times the amount of seeds, first pour the selected seeds into boiling water and stir quickly for 4 seconds, immediately pour cold water into another container, continue to stir until the water temperature drops to 30 ℃ and stop stirring, soak the seeds for 3 hours. Pay attention to the speed of hot seed, should not be too long, so as not to affect the seed germination rate.

3. Chemical disinfection: the seeds can be soaked in 100 times formalin for 30 minutes, or 2% bleach solution for 30 minutes, or 50% carbendazim 500 times solution for 1 hour, or 10% trisodium phosphate solution for 20 minutes, or 50% sulfonium bromide solution in 500 times solution for 0.5 minutes, or 500 times solution prepared by 10% antimicrobial agent 401 for 30 minutes.

Soaking seeds to accelerate germination

1. Seed soaking: seed soaking can accelerate the speed of seed water absorption and shorten the time of germination and emergence. The soaking time varies with water temperature, seed size and seed coat thickness. The water temperature is high, the seed is small, the seed coat is thin, and the seed soaking time should be short. It is suitable to soak seeds in cold water for 6 hours and in warm water for 3 hours at 25 hours and 30 hours, respectively. After soaking the seeds, wash the seeds with clean water and rub them repeatedly to remove the sticky matter from the surface to facilitate seed germination.

2. Accelerating germination: accelerating germination is to ensure that after absorbing enough water, the nutrients in the seeds are rapidly decomposed and transported for the growth of immature embryos, so as to promote the rapid germination of seeds under artificial control conditions. First rinse the soaked seeds with clean water, and then wipe off the excess water attached to the seeds with a cloth. A small amount of seeds can be wrapped in a wet cloth and put into an earthen pot and germinated under the condition of 28-30 ℃, while a large number of seeds should be accelerated by cloth-rolling method.

Sowing management

1. Seedbed preparation: watermelon seedbed should choose a plot with leeward direction, high dryness and convenient management to build a seedbed. Watermelon seedling raising in early spring should be carried out in greenhouse or greenhouse, electric hot line can be laid to increase soil temperature, and a small arch shed should be added to the seedling bed. In order to raise watermelon seedlings after autumn, sunshades should be built, and attention should be paid to preventing rainstorm erosion.

2. Soil configuration: the nutrient soil of watermelon seedling bed should be loose and free from diseases and insect pests, and N, P and K fertilizer should be applied in proportion, which is slightly sticky. It can be evenly mixed with 6 parts of paddy topsoil, 3 parts of rotten barnyard manure and 1 part of plant ash, and 5 kg of rotten chicken and duck manure per cubic meter of soil. Soil and fertilizer should be mashed and sifted, kept granular, then fully mixed with appropriate amount of water, and made 1-2 months before sowing.

3. Sowing at the right time: early-maturing watermelon was sown from mid-December to late March last year, medium-ripening watermelon was sown from April to June, and watermelon was sown in mid-late July after autumn extension. In the afternoon before sowing, the nutrition bowl was watered thoroughly. When sowing, put the seeds with bud tip flat in a nutrition bowl, 1 grain per bowl, covered with fine soil 1 cm thick, covered with film.

4. Seedling stage management

① temperature management: after sowing watermelon seeds, the temperature in the bed should be controlled at 28: 35 ℃ in daytime and 20: 25 ℃ at night. After 80% of the seeds were broken, the seeds were kept at 20: 25 ℃ during the day and 15: 18 ℃ at night. After the appearance of the first true leaf, keep it at 25: 28 ℃ during the day. Seedling refinement began one week before transplanting.

② water management: watermelon seedlings are generally not watered before they are unearthed. Watering should be controlled at the cotyledon stage, and the ground should be dry and wet, mainly to preserve soil moisture. The amount of water can be increased after the real leaves are on display. Should be watered in the morning in sunny days, after watering loose topsoil to preserve soil moisture, cloudy days should not be watered, and pay attention to film ventilation.