How to disinfect and accelerate the germination of cucumber in greenhouse in winter?

Before sowing cucumber, disinfection and germination treatment can effectively reduce the pathogenic bacteria carried by seeds and improve the seedling emergence rate, so it has become an indispensable link in cucumber planting, so today we will talk about seed treatment before sowing cucumber in greenhouse.

First, the disinfection of cucumber seeds

Before sowing, the number of seedlings should be determined according to the planting density of cucumber cultivated in greenhouse. Generally, about 2500~3000 seedlings per mu are cultivated in greenhouse by pruning single vine, and then the sowing amount is determined according to the germination rate of 90%. After selecting the seeds, the seeds should be disinfected according to the following operations.

1, seed drying

Before sowing, carefully selected seeds should be spread on cardboard or wooden board, and the thickness of seeds should not exceed 1cm. Put them in the sun on sunny days 1~2 days and turn over every 2 hours to make them dry evenly. Although airing seems simple, it is an essential process, because most seeds were stored in cold storage or seed bank before. If it is not aired, it is easy for seeds to emerge unevenly or not because of low vitality.

Step 2 soak the seeds in warm soup

Put the selected and dried seeds into warm water at about 55℃, and the amount of water is 5~6 times of the seed volume. Soak the seeds while stirring, and keep the water temperature at 55℃ for about 15 minutes. When the water temperature is about 25~30℃, start to rub the seeds, rub off the gelatinous substances on the surface of the seeds, rinse them clean, and soak the seeds for 3~5 hours at room temperature.

3. Soak the seeds in hot water

For cucumber grafted pumpkin with thick seed coat, the seeds can be scalded with hot water at 70℃ which is five times the volume of the seeds. After putting the seeds into hot water, stir them quickly for 30 seconds, then pour in cold water to make the water temperature reach 30℃, and then enter the normal warm soup soaking procedure. For coated seeds, washing is unnecessary.

4. Dry heat treatment

Sun-dried cucumber seeds (water content about 6%) can be put into a 70℃ thermostat or oven for 72 hours, which can effectively kill germs and viruses inside and outside the seeds.

5, drug disinfection

For local common diseases, selective chemical disinfection can be carried out.

A variety of germs on the surface of seeds: soak the seeds in 2%~3% bleaching powder solution for 30 minutes or in 0.2% potassium permanganate solution for 20 minutes. Virus disease: Seed can be soaked in 10% sodium phosphate solution for 20 minutes. Anthracnose, Fusarium wilt, Fusarium wilt and root rot: You can choose 50% carbendazim or 500 times thiram wettable powder or 500 times iprodione wettable powder to soak the seeds for 20 minutes. Anthracnose and Fusarium wilt: soak the seeds in 40% formaldehyde 100 times solution for 20 minutes. Rhizoctonia solani and Phytophthora blight: 3000 times solution of 97% hymexazol wettable powder and 800 times solution of 72.2% propamocarb hydrochloride aqueous solution can be selected for seed soaking for 30 minutes. When using chemicals for disinfection, it is necessary to strictly control the disinfection time, and rinse it with clear water several times immediately after disinfection.

Second, accelerate seed germination.

1, soaking seeds before germination

Generally, soaking seeds at room temperature for 6~8 hours to accelerate germination is appropriate; Soaking seeds in warm soup can be reduced to 2~4 hours.

2. Germination temperature and time

The suitable temperature for accelerating cucumber germination is 28℃~30℃, and lower than 15℃ or higher than 40℃ is not conducive to cucumber seed germination. The time required for accelerating germination is 1~2 days. When the seeds are exposed about 70% (that is, the radicle is 0.3~0.4㎜), the germination can be stopped and sowing can be carried out.

3. Method of accelerating germination

The slightly dried seeds after soaking are wrapped with wet gauze, wet cotton cloth or wet towel, covered with moisture-proof plastic film, and then covered with heat preservation material. If conditions permit, the seeds can also be wrapped in wet cloth and put into a constant temperature box for germination. The temperature in the box is set to 30℃, and the relative humidity is kept above 90%, and it is turned 1 time every 4 hours until the seeds turn white.

If it is a coated seed, it should be tiled, and the thickness should not exceed 3㎜. In the process of accelerating germination, seeds should be turned 1 time every 4~5 hours for ventilation and timely water supplement.

By soaking, disinfecting and accelerating germination of seeds, the pathogenic bacteria carried by seeds can be cleaned up and the incidence of diseases in the later stage can be reduced. At the same time, the basic work of cultivating strong seedlings has been laid. Especially the indoor conditions of cucumber planted in winter are poor, so we should pay more attention to seed soaking, disinfection and germination.