Best Guide of Common Plant Disease in Garden

For home gardeners, nothing is more frustrating than seeing their work destroyed by pests and diseases.

The disease occurs when environmental conditions are suitable for the growth of pathogens on susceptible hosts. Some pathogens attack a variety of plants, while others attack only specific plants. In addition, some pathogens can attack all parts of the plant, while others attack only selected tissues.

Many types of organisms cause plant infections, but the top five types of plant pathogens are fungi, water molds, bacteria, viruses, and nematodes. Adverse environmental conditions may also lead to non-infectious diseases of plants, called diseases. Adverse conditions include inappropriate soil pH, nutrient deficiency and toxicity, soil compaction, excessive water content, and herbicide destruction. Plants weakened by adverse conditions may be more vulnerable to pathogens.

The following is a brief introduction of several common plant diseases, symptoms and solutions, I hope to help some growers.

1. Powdery mildew: powdery mildew is a fungal disease, which is easy to occur in the environment of heat, humidity and no ventilation. It often harms the flowers and trees of the leaves, stems and flower stalks and other parts, the surface of a layer of white powder, serious disease when the leaf wilt.

In the sweltering heat of summer, the leaves yellow and rose ‍ and melon leaf disease easily. Prevent and cure powdery mildew to want to increase illumination and ventilated drop temperature dehumidify, can add biofertilizer reasonably additionally, enhance plant disease resistance ability and reduce soil-borne diseases.

Already diseased plants can be sprayed with some medicaments such as carbendazim for prevention and treatment.

2. Grey mold disease: it is caused by the infection of bostospora cinerea, which is a fungal disease. the growth temperature of the pathogen is 20~30℃, and in the low temperature and high humidity environment is more prone to disease, When the temperature is 20~25℃ and the humidity lasts for more than 90%, it is the peak period of diseases.

The fruit is infected, the stigma that remains or petal is infected more first, after be spread to the fruit, cause fruit skin is grayish-white, have thick gray mildew layer, show water rot shape, leaf disease starts from leaf tip, along leaf vein becomes "V" shape to expand to the inside, drab, the side has the striate line of dark and light alternate with.

This disease is a typical airborne disease, which can be spread by air, water, and farming. In the actual disease control process, it is difficult to take effective measures to completely cut off the source of infection; In the case of pathogen invasion, it is difficult to completely eliminate the pathogen, such as drug spraying, it is difficult to solve the air and dew pathogens, And alone fume shed, cannot focus on the disease leaves, disease fruit and other diseases on the body or internal pathogens. Therefore, we must do early disinfection and prevention before planting.

3. Soft rot: a bacterial disease that occurs in high temperature and humidity. The bacteria enter the tissues from the wounds in the leaves and roots of the plants, secrete toxins, make the tissues necrotic, absorb nutrients from them, and reproduce and spread to the surrounding areas. The affected plant tissue becomes a translucent milky yellow slime with an odor. 

In addition to improving the environment and the air, it is important to prevent soft rot. Want to avoid the page to spray water additionally, cut off disease leaf in time, when large area suffers, can use streptomycin to undertake prevention and cure.

4. Root rot: it also known as black stem disease, black rot, is caused by the fungus, nematodes, bacteria plant disease, often in the high temperature, high humidity environment. Root rot often occurs in the roots and spreads upward. The stems of plants rot and turn black. The function of absorbing water and nutrients is gradually weakened. When the disease is serious, the leaves of the whole plant become yellow and shriveled, and the root skin becomes brown and dry, and part of it is separated from the pith. Finally, the whole plant dies. 

How to prevent, the first is ventilation cooling, improve the environment; Next want scientific cultivation, reasonable water fertilizer, make the plant healthy, raise oneself disease resistance; In addition to doing a good job of soil disinfection. In the early stage of the onset of succulent plants, the diseased parts can be excised and re-rooted after drying.

5. Leaf spot disease: also known as brown spot disease, black spot disease, is a fungal disease, in the high temperature, sultry, not a ventilated environment comfortable to occur. At the beginning of the disease, the affected leaves appear small circular black spots, which gradually expand into a circular or nearly circular shape. Prevention is mainly to improve the environment, ventilation, transparent, cooling, and timely cut off, burned disease leaves, prevention, and cure the infection. Severe cases can be sprayed with methyl topazine or carbendazim and other drugs.

6. Anthracnose: a fungal disease that attacks the leaves and young stems of plants. When the indoor high temperature is sultry summer comes on more serious. Leaf damage often appear round or elliptic disease spot, the center is grayish-white light brown, the edge dark brown, late disease spot will have black spots, when serious leaf death, young budtender stem disease often cause decay. Summer heat. The prevention method is the same as three points: there are three prevention methods below. First, improve the environment, ventilation cooling; Secondly, reasonable fertilization to enhance plant resistance; Do a good job of soil disinfection, timely remove the diseased plants and destroy; Can spray chlorothalonil, carbendazim, and other drugs for control.

7. Viral Disease: a disease caused by parasitic plant viruses. Plant viruses must live in the host cell parasitic, highly specific, a virus can only infect a certain kind of plant or some plants, but there are a few widespread damages, such as Tobacco mosaic virus and cucumber mosaic virus. The manifestations of viral diseases can be divided into four types: mosaic, yellowing, necrotic and malformed. In addition to the above two, the more common tomato mosaic virus disease, Jujube Witches Broom. The treatment of viral diseases is also difficult, especially the damage to woody plants is devastating, insect pests such as aphids and planthoppers are the main disseminators of plant viruses, so to prevent the spread of viral diseases must do a good job in pest control.