Ginkgo planting: what is ginkgo stem rot?

What is ginkgo stem rot? What harm does ginkgo stem rot have? What tree age does ginkgo stem rot mainly occur in? How to prevent and cure the stem rot of Ginkgo biloba Please introduce how to control the stem rot of Ginkgo biloba. The stem rot of Ginkgo biloba mainly occurs in the seedling breeding area. generally, 1-2-year-old ginkgo seedlings, especially one-year-old seedlings, often cause a large number of seedlings to die. Symptoms of stem rot of ginkgo biloba: at the initial stage of the disease, the seedling base turned brown, the leaves lost normal green, and drooped slightly, but did not fall off. The susceptible site rapidly expanded upward, so that the whole plant withered. The basal cortex of the diseased seedling was shrunk, and the intradermal tissue was spongy or powdery, with many small black sclerotia. The pathogen can also invade the xylem of seedlings, so small sclerotia can sometimes be seen in the brown hollow pith. After that, the pathogen gradually spread to the root, causing the root bark cortex to rot. If you pull out the diseased seedlings by hand, you can only pull out the xylem and leave the root cortex in the soil. The stem rot of Ginkgo biloba cuttings can also occur under the condition of high temperature or low temperature, which can make the cuttings epidermis sleeve on the xylem and all the phloem parenchyma blacken and rot. The cause of stem rot of Ginkgo biloba: stem rot pathogen usually lives saprophytic in soil and belongs to weak parasitic fungi. Invade from the seedling wound under suitable conditions. Therefore, the occurrence of the disease is related to the host and site environmental conditions. The root cause of seedling damage is due to the high surface temperature, the base of the seedling is burned by high temperature, resulting in the invasion of bacteria. The lower the degree of Lignification of seedlings, the higher the incidence of the disease. When the seedbed was low-lying and stagnant water, the incidence also increased significantly. From June to August, when the high temperature of the seedling bed reached more than 30 ℃, the 10~l5d of ginkgo cuttings began to occur, and when it was serious, the scion blackened and died. The results showed that antagonistic actinomycetes could effectively inhibit the spread of the disease. Prevention and control methods of ginkgo stem rot: according to the causes of ginkgo stem rot, prevention should be given priority to at present. 1. Sowing early to sow as soon as the soil is thawed, this measure is beneficial to the Lignification of seedlings in the early stage and enhance the resistance to high temperature on the soil surface. 2. Reasonable dense sowing is beneficial to give full play to the group effect of seedlings and enhance the resistance to the adverse environment of the outside world. The experiment showed that the smaller the seedling density, the higher the incidence, and the higher the density, the lower the incidence. Practice has also proved that in the past, after sowing 25~40kg seeds per mu, such as changing the sowing rate of 80~l00kg seeds per mu, not only the incidence decreased, but also the seedling yield per unit increased, which not only saved the land but also reduced the disease. 3. After the seedlings of underground pests are harmed by underground pests, they are easily infected by stem rot pathogens. Therefore, attention must be paid to the elimination of underground pests before and after sowing. 4. to prevent the mechanical damage of seedlings, the seedlings sown in the same year or the seedlings transplanted in the year must be careful not to damage the roots of the seedlings in the process of weeding or planting, otherwise it is easy to cause stem rot. 5. Shading and cooling in order to prevent the increase of ground temperature caused by solar radiation, measures such as setting up a shade shed, covering grass between rows, planting corn, cutting and shading should be taken to reduce the harm to seedlings. 6. Irrigation and spraying should be timely in order to reduce the surface temperature in the high temperature season, and spraying should be adopted where there are conditions, which is more conducive to reducing the occurrence of diseases. 7. Medicine and biological control combined with irrigation can be sprayed with various fungicides such as topiramate, carbendazim, Bordeaux solution and so on. Antagonistic actinomycetes can also be added when topdressing organic fertilizer in the middle of June, or plant ash / superphosphate (1GB 0.25) and antagonistic actinomycetes can be added. Click for more ginkgo tree planting techniques click to get more flower planting techniques