Second, burn roots. (1) Symptoms: The watermelon roots are yellow, no new roots are produced but no rot, roots grow slowly, and the plants are short and brittle, forming small old seedlings. (2) Preventive measures: Use appropriate amount of fertilizer when preparing earthworms, especially to avoid excessive use of chemical fertilizers. Normally, 0.5 kg of diammonium phosphate, 0.5 kg of potassium sulfate, 80 grams of carbendazim, and 60 grams of trichlorfon per cubic meter of nutrient soil. Mix well; organic fertilizer should be fully cooked to prevent fertilizer damage; nursery should be timely watering, keep bed soil moist, and take measures such as warming, heat preservation, in order to facilitate root growth. Third, tall seedlings. (1) Symptoms: The young stems are slender and light in color; the cotyledons are thin and small, and the leaves are light green. In the seedling stage, there are many nitrogen fertilizers, lack of light, and high temperature and humidity are prone to seedling growth. (2) Preventive measures: maintain a relatively high temperature (30-35°C) before emergence, 70-80% of seed emergence, proper ventilation, dehumidification, generally maintain daytime 20-22°C, nighttime 15°C; continuous rainy weather, using incandescent Lights are supplemented with light; reasonable fertilization, without partial application of nitrogenous fertilizers, additional phosphorus and potassium fertilizers, spraying 0.3% potassium dihydrogen phosphate solution 2-3 times at the seedling stage. Fourth, stiff seedlings. (1) Symptoms: The seedlings grow slowly, the young stems are short, the cotyledons are small and thick, the leaves are grayish green, the roots are thick and short, and there are no lateral roots. Low soil temperature, high humidity or fertilizers, and herbicides, etc., can easily induce a weak seedling. (2) Preventive measures: Select loose, good-permeability vegetable garden soil as nutrient soil, nutrient soil as early as possible; use electric hot-line nursery to cultivate strong seedlings; decompose organic fertilizer and appropriate amount of nitrogen and phosphorus 20-30 days before planting Potash fertilizer, fertilizer and soil should be mixed evenly; planting field, 72% Dole EC per acre 80-100 ml or 96% Jindul EC 40-50 ml water 40-50 kg sprayed soil, 5-7 days after the colonization of watermelon Seedlings; to avoid the improper application of herbicides caused by stiff seedlings; planting after the emergence of a frozen seedlings, spraying more than 6000 times the love, Hui Manfeng 800 times. As a botanical alternative to tobacco, Original E-Cigarette provides true smoking experice.It is closest to the taste of traditional cigarettes,Customers can easily adapt to this taste,This is the best choice for people who are addicted to cigarettes. It also gives you a feeling of relaxation,it provides smoking enjoyment without nicotine.It can effectively help people quit smoking.For smokers, this is a very good option to get rid of traditional cigarette damage. Original Cartridge,Original E-Cigarette,Original Cigarette Heatsticks,Original Cigarette Heatsticks Alternative Dongguan Vanilla Bioengineering Co., Ltd. , https://www.healthecigarette.de
One, roots. (1) Symptoms: The roots of watermelons do not produce new roots. After the roots become brown, they rot. The cotyledons and true leaves become thin. They are yellow-green or milky yellow. The leaf margins are scorch and the shoots are wilting. Seedlings encounter a low temperature and high humidity environment. (2) Preventive measures: Use greenhouses and small sheds to provide hotline for nutrition seedlings; strengthen seedbed management; soil temperature at seedling stage is controlled at 15-25°C; daytime temperature of cotyledons and two true leaves is controlled at 22-28°C during the night. Temperature 18-13°C, control watering at seedling stage, encounter continuous rainy weather, use incandescent lamps to supplement light, reduce the occurrence of yellow leaves; after the new roots of melon shoots, spray 0.3% potassium dihydrogen phosphate solution, Hui Manfeng ( Gao Mei Shi) 800 times liquid, love more than 6000 times liquid, promote root growth and development.