1. Symptoms:
Maize big spot mainly damages the leaves of corn. When it is serious, it also damages the leaf sheath and temporal lobe. It starts from the lower leaves of the plant and then spreads upward. The lesions are long spindle-shaped, gray-brown or tan-colored, 5-10 cm long and 1 cm wide. Some lesions are larger, and the leaves are coked when severe. When the weather is wet, there may be dense gray mold layer on the lesions. In addition, there is a lesion that occurs on disease-resistant varieties, extending along the veins, with brown necrotic streaks, which generally spread slowly. Summer corn is generally more severe than spring corn.
2. The law of onset:
Pathogens are overwintering on field residual diseased plants (both mycelia and conidia) and are the primary source of infection for the second year of onset. The onset temperature is 20-28°C. When the conditions are appropriate, the germs reproduce rapidly, producing a large number of conidia, spread by the wind. The prevalence of the disease is mainly determined by the environmental conditions (rain, humidity), except for the susceptibility of the maize variety.
3. Control measures:
1 Select disease resistant varieties;
2 reasonably dense planting, increase organic fertilizer and phosphorus, potash;
3 At the beginning of the disease, use 50% of wet carbendazim 500 times or 50% of bacteriocin 800-1000 times, or use 80% thiophanate-methyl 800-1000 times of liquid, 50-75 kg of liquid per acre. 7 to 10 days once the spray, a total of 2 to 3 times control.
China: In accordance with Article 54 of the Food Hygiene Law of the People's Republic of China, Article 28 of the Hygiene Management Measures for Food Additives, Article 2 of the Hygiene Management Measures for Food Nutrition Enhancers and Article 99 of the Food Safety Law of the People's Republic of China, food additives are defined as: Food additives refer to artificial or natural substances added to food for the purpose of improving quality, color, aroma and taste of food and for the purposes of preservative, fresh-keeping and processing. According to GB 2760-2014 National Food Safety Standard for The Use of Food Additives, food additives are defined as "artificial or natural substances added into food for the purpose of improving food quality, color, aroma and taste, as well as for the needs of anti-corrosion, fresh-keeping and processing technology. Spices for food, base agents in gum-based confectionery and processing AIDS for food industry are also included.
Food Addictives Powder,Tryptamine Powder,Beta-Nicotinamide Mononucleotide Powder,Sucralose Bulk Food Additives
Shaanxi YXchuang Biotechnology Co., Ltd , https://www.peptidenootropics.com