What are the reasons for the low survival rate of sexual reproduction in Gastrodia elata?

Gastrodia elata is a precious Chinese medicinal herb in China, and its cultivation area has been expanding year by year. Due to the degeneration of varieties in asexual reproduction, yields are low and unstable, and quality declines, which has affected commodity exports. At present, most growers use sexual crossbreeding to propagate seed tubers to solve the problem of yield reduction caused by variety degeneration in Gastrodia elata. However, there are also problems such as lack of proficiency in the technology and uneven quality of breeding, which have restricted the rapid development of Gastrodia elata, leading to the abnormal phenomenon that the more it is developed, the fewer the products and the higher the market price. Those who fail gain very little from the huge investment they made, which has greatly dampened farmers' enthusiasm for development. In response to the above problems, the reasons are analyzed as follows.

I. There is blindness in sexual reproduction breeding

Sexual reproduction of Gastrodia elata is a high-tech breeding technique successfully researched only in recent years, and its requirements are quite strict, because Gastrodia elata involves multiple disciplines (botany, mycology, soil science, natural science, and so on). Failure in any one discipline or a small mistake in even one link can lead to total failure. It is not like crops @#@245@#@ or corn, which are easy to plant and manage and can be grown in both the north and the south. Many introducers, regardless of their own latitude and altitude, their natural environmental conditions, or whether they have mastered the complete set of techniques, blindly introduce it on a large scale, which is one of the causes of failure.

II. Delay in sowing season

Gastrodia elata prefers a cool natural environment. The suitable breeding time is from March to April. In a high-temperature and humid environment, the vitality of the germination fungus weakens and eventually dies. At present, most sexual reproduction relies on simple and crude equipment, without heating and forcing facilities, and relies on the sword-leaf Gastrodia to grow and set seed under natural temperatures. When it matures, it happens to encounter the high-temperature season that is unfavorable for Gastrodia elata seed germination and germination fungus growth. The tiny Gastrodia elata seeds simply cannot be timely colonized by the germination fungus and thus cannot germinate, fail to form protocorms, and the process fails.

III. Lack of strict selection of Armillaria strains

Gastrodia elata is a special product formed through its association with Armillaria. Without excellent and vigorous Armillaria, growing Gastrodia elata is just empty talk. Armillaria is an important discipline in Gastrodia elata technology, and there are many varieties, including Armillaria mellea, Armillaria luteovirens, and false Armillaria. In terms of rhizomorph classification, there are thin-line fungi, thick-filament Armillaria, and flat broad-band Armillaria, among others. Most introducers have only a superficial understanding of the technology and insufficient knowledge of the fungal strains. They find it difficult to distinguish dead fungi from live fungi, and even less able to clarify whether the fungal varieties are true or false, good or bad. Regardless of whether the fungal strains are strong or weak, alive or dead, they only apply more in an effort to increase yield. As a result, at harvest the following year, not a single one can be seen, and the losses are heavy, greatly damaging their vitality.

IV. The unscientific planting method of "rushing for success and seeking to accomplish everything in one step"

Throughout its life, Gastrodia elata must rely on Armillaria to supply nutrients in order to grow and develop. The seed tubers and Armillaria must combine in a timely manner to produce a beneficial cyclical relationship. This is the key to success with Gastrodia elata. Although Armillaria is not the food of Gastrodia elata, it is an elite force transporting supplies for Gastrodia elata to win the battle, and it bears a crucial task in the growth of Gastrodia elata. Before troops and horses move, supplies must go first. Most introducers ignore the key link of first cultivating the fungal material and then planting the Gastrodia, and the formation of large clumps by Gastrodia elata. They seek quick profits, rush for success, and try to accomplish everything in one step, using the one-time planting method of seed tubers, Armillaria strains, and new material all at once. This leads to the seeds germinating and forming protocorms, but because the time is too short, Armillaria cannot yet connect to the new material. The protocorms then starve to death entirely because they cannot receive timely nutrient supply. As a result, at digging time, one sees only Armillaria rhizomorphs wrapped all over the rods, but no empty nests where Gastrodia tubers have grown.

V. Inaccurate control of dryness and moisture at sowing

Gastrodia elata seeds are extremely small, have very weak vitality, and also have a very short lifespan. They have very strict requirements for the degree of dryness and moisture of the sand and leaves at sowing. Either dryness or excessive moisture can kill the seed tubers within a short time. Many growers do not pay enough attention to this point, and many fail to meet the standard for dryness and moisture. In fact, carelessness in this small link has caused many people to toil without gaining anything.

VI. Careful planting, rough management

Planting is three parts planting and seven parts management. Gastrodia elata is a special planting industry that requires attention to every aspect and all details, and is very strict. If one only invests in large-scale development and does not seek refinement and careful management, it is very difficult to succeed with high yields. Some people also succeeded in planting on a small scale at forest edges and in orchards, and assumed that there was no great knowledge in it and that it was very simple, so they planted on a large field scale, hoping to catch the trend and make a profit. They ignored its growth characteristics, did not set up shade sheds or create a suitable micro-environment, and under the strong direct sunlight and exposure of the high-temperature summer, the ground temperature rose and exceeded the suitable temperature limit for Gastrodia elata, causing even the already grown Gastrodia elata to suffer from the heat and suffocate, let alone the small ones. As a result, at harvest time the Gastrodia elata became large empty skins, the so-called abnormal phenomenon of mycelium eating the Gastrodia elata. The investment was large and the losses were also large, and those who wanted to prosper instead became poor. To grow Gastrodia elata well, one must plant and manage it carefully and scientifically in order to achieve the expected goal.