At present, cotton is in the seedling stage, which is a crucial period for cultivating strong seedlings, promoting early seedlings, and providing high-yield cotton for early harvesting. Due to the low temperature in the early stage, the deep sowing, or the poor maturity of the seeds, especially the recent rainy weather and large soil moisture, the cotton seedlings have serious diseases at the seedling stage. If they are not timely prevented, the light ones will affect the growth of cotton seedlings. Forming strong seedlings, not good for the shelf, and the heavy ones cause dead seedlings. Therefore, it is very important to pay close attention to, correct diagnosis and timely prevention.
First, the symptoms:
1, blight disease. The cotton seedlings were killed before they were unearthed, causing rotten seeds and rotten buds. After the seedlings were unearthed, the spots on the base of the young stems close to the ground appeared yellowish brown, and the lesions that turned black were gradually enlarged, surrounding the entire base of the stem, and eventually the seedlings died. Pulling up the diseased seedlings, it is obvious that the diseased part and the surrounding soil often have hyphae. Cotyledons are damaged, and irregular yellow-brown lesions appear in the middle.
2, anthrax. Cotton seedlings can be seen before they are unearthed, and hypocotyls and young roots turn brown and rot. The seedlings of unearthed cotton seedlings have reddish-brown small spots at the base of the stem, and the fusiform streaks with purple-brown depressions are enlarged, and the lower limit of the longitudinal slits is often contracted around the waist. In humid conditions, the lesion can develop in depth and reach the top of the young stem to form a top rot. After the root is infested, it is dark brown and semi-wet and rot. After being pulled up, the cortex is not easy to break, which is different from the blight. The incidence of cotyledons is mostly semi-circular pale brown to brown lesions on the leaf margin, and the edges are reddish brown; in wet weather, the surface of the lesions produces orange-red sticky spores.
3, red rot disease. The cotton seedlings were damaged before they were unearthed, and the young shoots turned yellow brown and rot. The roots of the unearthed cotton seedlings were damaged, and the root tip first turned pale yellow, then browned and rotted, and gradually spread throughout the roots. The young stem base is damaged, first turned yellowish brown, then turned dark brown and rot, and the lesions are not sunken. The main stems and the tender stems of the ground become coarse and produce brown short streaks, which is the main feature of the disease. Cotyledons are damaged, and more gray-red irregular or nearly round lesions are produced at the edges. The lesions often rupture, and the pink part of the disease is produced in the diseased part.
4, smashed the disease. The main symptoms are that the seedlings are light brown from the base and soften and fall down. The cotyledons are also softened and stained with water stains. The disease develops rapidly, so it is called squatting. Most of the pathogens first invade from young and fine roots and extend to young stems and whole seedlings. When the soil moisture is high, the seeds and newly germinated sprouts can also be infected, affecting emergence or forming weak seedlings. White fine flocs are sometimes seen on the fallen dead seedlings.
Second, prevention and treatment methods:
Due to the variety of cotton seedling diseases, it is often mixed with several diseases, and it is affected by environmental conditions and the disease resistance of cotton seedlings. Therefore, on the basis of prevention and treatment of seed disinfection and soil treatment, focus on seedlings Stage cultivation management and chemical control measures.
1. After cotton emerges, the ability to absorb inorganic nutrients is weak, the leaf area is small, and the organic nutrients produced by photosynthesis are not sufficient. Coupled with the adverse weather environment, root growth is more difficult, which increases the incidence of diseases. Therefore, the cultivation of cotton at the seedling stage and the improvement of the ground temperature are necessary means to solve the disease at the seedling stage. And to do early, deep, and diligent.
2. Chemical control. Spray 1-2 times of humic acid foliar Fertilizer after emergence to improve the resistance of cotton seedlings to low temperature and disease resistance. Spray 50% carbendazim WP or 70% thiophanate-methyl WP 800 times solution + 70% mancozeb WP 600 times solution or carbendazim WP 3000 times solution for irrigation The roots are controlled once every 5-7 days according to the situation, and the continuous control is 2-3 times, and the effect of foliar fertilizer is better.
A pigment is a substance that can stain an object. Pigments can include many products, we mainly supply lithopone. It is used as a base for lake pigment and used as a inert pigment for paint, ink and cosmetics as well as in a large range of applications in plastic industry.
. It is used as a filler in paper, leather, and linoleum.
Lithopone B301 is our regular exporting product. We are the main supplier in the north of China.
Organic Pigments,Organic Yellow Pigments,Inorganic Pigments,White Inorganic Pigments
SJZ Chenghui chemical co ltd , https://www.chenghuichemicals.com