Brown spot disease
Brown spot disease often harms the vegetation such as melons and fruits, vegetable cash crops and flower lawns, and is one of the common fungal diseases of crops, and the prevention and control should be based on the combination of physical methods and chemical treatment.
First, the characteristics of the hazard
The pathogen began to appear a number of brown dots, with the continuous expansion of the dots, the spots are connected to each other into pieces, resulting in gray-brown mold hyphae, the affected leaves start from the petiole, from green to brownish yellow early shedding, seriously affecting the growth and development of rhododendrons and ornamental value.
Four ways to recognize brown spot disease [take citrus as an example]
1. With tail whisker spots
Brown spot fungus mainly harms young leaves, new shoots and young fruits, and in severe cases causes leaf fall, fruit fall and dead shoots. The brown spots produced on the affected leaves often have tail whiskers, forming an eye-shaped lesion.
2. Slightly concave, yellow halo
Small brown to black spots or spots are formed at the site of the lesion, which vary in size, round or oval, slightly concave, and have a yellow halo.
3. The branches bend and die
The symptoms of harm on young shoots are similar to those on leaves, and the number of spots varies in number on the branches and can spread along the transporting tissue. When the disease spots surround the branches in half a circle, the branches bend and wrap around, and the branches die.
4. The surface of the young fruit is pegged and cracked
The onset of the young fruit immediately after the flowering, the spot is needle-like at the beginning of the disease, and then expands into a sunken black-brown spot, and the young fruit falls off in severe cases. The spots of young fruits that do not fall off bulge as the fruit expands, and the surface of the wood is bolstered and cracked.
Second, the law of occurrence
The infection time of brown spot disease is generally in mid-to-late May, as long as there is 10 mm of rain or more than 6 to 8 hours of leaf dew at night, brown spot disease will infect the leaves. The infection of brown spot fungus is spread by rainwater, which falls to the ground and splashes on the leaves near the ground, first infecting the leaves near the ground, and then infecting the inner chamber and upper part. Low temperature latency is long, high temperature latency is short. The optimal temperature for the onset of brown spot disease is 20 to 25 degrees. Heavy rainfall and humidity are the conditions for the prevalence of brown spot disease, and high temperature and high humidity create conditions for the outbreak of brown spot disease.
3. Comprehensive prevention and control
1. Strengthen the fertilizer and water management of orchards and improve the disease resistance of fruit trees. In recent years, the fertilization of orchards has adopted the method of balanced fertilization, and the optimal fertilization methods of organic fertilizers, nitrogen, phosphorus and potassium and trace elements have been selected according to the scientific proportion and quantity, and supplemented to fruit trees, so as to meet the best needs of fruit trees for various nutrients. In this way, the fruit tree can only carry out normal growth and development during the growing season, and the tree is also strong, and the ability to resist pests and diseases will be enhanced.
Recommended use of [COMPO Schneord compound fertilizer + amino acid foliar fertilizer]
【Amino acid foliar fertilizer】
1. Rich in plant-derived amino acids and highly active polypeptides, it promotes the rapid absorption and utilization of crop nutrients;
2. It contains photosynthetic induction substances, improves the net photosynthetic rate of leaves, and provides sufficient photosynthetic products for crop growth and development;
3. Enhance the crop defense mechanism, improve the resilience of crops to stress, and reduce the damage to crops from low temperature, drought and other adversities.
【High-tower nitrothio compound fertilizer】
15-15-15、20-5-15、15-5-23
1. Highly active biostimulant, improve crop stress resistance, and can "prevent disease" nitro fertilizer
2. Promote nutrient absorption and transport, and "increase production and improve quality" of nitro fertilizer
3. Schnodder DMP technology, stable and long-term effect, "not afraid of the end", "fruit shoots with the promotion" of nitro fertilizer.
2. After the fall of fruit trees every year, clean the fallen leaves in the orchard in time, bury them deeply or shallowly into the soil, and reduce the source of overwintering diseases.
3. Adjust the density of fruit trees in the orchard, carry out reasonable shape and pruning, and improve the ventilation and light transmission conditions of the orchard.
4. Do a good job of drainage in low-lying orchards.
5. According to the incidence of brown spot disease, the drug should be applied at the right time in the spring shoots, young fruit stage and fruit expansion stage, of which the prevention and treatment of 3 to 5 cm in the spring shoots and the flowering stage is the most critical, and the spray is 1 to 2 times in the autumn shoots according to the incidence.
Recommended use 【Fengliang + NakashengButsu + Arcadian】
【Fengliang】
Pyrazole ether ester is a novel broad-spectrum fungicide that is a mitochondrial respiratory inhibitor that prevents electron transfer in cytochrome synthesis. It has protective, therapeutic, leaf osmotic conduction effects.
Diethylmethicazole belongs to the triazole class of fungicides, which mainly inhibit the biosynthesis of ergosterol in pathogenic cells, thereby destroying the structure and function of cell membranes. The mixing of pyrazole ether bacteriolate with phenylmethocyclazole has a good preventive and therapeutic effect on watermelon anthrax.
【Nakasang Bujin】
1. It has a good control effect on fungal and bacterial diseases at the same time.
2, the crop is very safe, flowering, young fruit can be applied.
3, good mixing.
4. It has inhibitory effect on leaf mites and pathogenic nematodes.
【Arcadian】
1. Promote the balanced and robust growth of various organs of crops, which has a two-way regulatory effect. Promote the root of the strong rod, resist lodging.
2. Enhance the vitality of crops, disease resistance, drought resistance, cold resistance and salt resistance.
3. Increase the chlorophyll content, make the leaves thicker, the leaf color is thick green, and improve the photosynthetic efficiency.
4. Alleviate drug damage, fertilizer damage, and avoid aphids, cattle, sheep, etc.
5. PH9-11 neutralizes soil acidity.
【Disclaimer】
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