Control methods of diseases and insect pests of Gastrodia elata

I. Disease and its control

1. The cause of the disease. The pathogens of Gastrodia elata disease are mainly basidiomycetes other than Armillaria mellea in fungi, which infect the fresh and fungus materials of symbiotic Armillaria mellea and compete with Armillaria mellea for nutrients, which will not only inhibit the growth of Armillaria mellea and reduce the yield of Gastrodia elata. It will also directly infect the tuber of Gastrodia elata, causing Gastrodia elata rot soft rot (called tuber soft rot) or rot death (called tuber rot). Most of the disease is in bad environment, such as high temperature, high humidity, poor air permeability and so on, which is not conducive to the growth of Gastrodia elata, which leads to the yellowing of the tuber skin, the decay of the central tissue, the internal slurry, and finally the death of the rotten, smelly shell.

2. Prevention and control methods. One is the strict selection of Gastrodia elata species. The excellent Gastrodia elata species with no more than three generations of asexual reproduction, obvious growth point, budding, aseptic and disease-free should be selected in production. It is best to choose the zero generation or the first generation of hybrid Gastrodia elata. Asexual reproduction of multiple generations of Gastrodia elata species due to species degradation, adaptability and stress resistance weakened, resulting in diseases or low yield or even no harvest after cultivation. When selecting Gastrodia elata seeds, if you find that the seed is not full, the growth point is not obvious, and there are signs of decay (even a little bit) should be discarded. The second is the strict selection of Armillaria mellea materials. When cultivating fungus materials, Armillaria mellea seed materials without miscellaneous bacteria should be selected, and seed materials and fungus materials infected by miscellaneous bacteria should be eliminated in time. The appearance characteristic of distinguishing Armillaria mellea from miscellaneous bacteria is that the hyphae of Armillaria mellea are pink and white and grow in the bark; the front end of the fungal cord of Armillaria mellea is white, the middle is reddish brown, the tail is black, round, and the network is intertwined on the surface of the fungus, glowing in the dark (fluorescence). The miscellaneous bacteria are generally monochromatic, such as white, green, ink, etc., mostly attached to the surface of the bark, showing a bundle-like, flaky or fan-shaped distribution, and do not glow in the dark. The third is the strict selection of cultivation environment and cultivation site. In the field cultivation, we should choose the barren land without miscellaneous bacteria or with less bacteria, do a good job of disinfection and sterilization during cultivation, and pay attention to cleanliness and sanitation in indoor cultivation.

II. Insect pests and their control

The common pests of Gastrodia elata are mole cricket, grub, white ant and so on. Mole cricket uses adults or larvae to dig vertical and horizontal tunnels under the topsoil layer and chew on Gastrodia elata tubers; grubs are the larvae of beetles with miscellaneous feeding habits and wide distribution, and can bite the tubers of Gastrodia elata into holes or destroy the developing terminal buds of Gastrodia elata; termites not only gnaw the tubers of Gastrodia elata, but also eat the hyphae and fungal cords of Armillaria mellea. The first method of prevention and control is manual hunting and killing. Once the uplift of soil or sand in the cultivation site is found, the soil or sand can be removed and killed manually. The second is light trap. With the help of the phototaxis of most insects, a black light is set up in the Tianzhu cultivation ground to trap and kill adults. The third is drug entrapment. When it is found that white ants are harmful, mirex or anti-pest powder can be scattered in the cultivation site, and several pine boards can be put around the cultivation ground or on fungus and fresh wood to lead white ants to be eliminated on the pine board. Fourth, phoxim or trichlorfon is used to control the above underground pests before cultivation.