In July this year, in the exhibition greenhouse of the National Botanical Garden (North Garden), three konjac blossomed one after another, setting off an online flower viewing craze. Just recently, two of the konjac plants have been fruiting for the first time, and the fruit order is like two bright torches, which once again "ignited" Weibo hot searches. What's so strange about this plant? Why can even bear fruit attract the public's attention? To this end, the reporter exclusively interviewed Wei Yu, executive deputy director of the North Park of the National Botanical Garden, and asked her to introduce the detailed process of the blooming and fruiting of the troll konjac group this time.
The extremely difficult flower to bloom
troll konjac firstly in its "rare". It is one of the three flagship species of rare and endangered plants in the world, and is only distributed in tropical rainforests in western Sumatra, Indonesia. Secondly, its "giant" is its "giant" - it is not only large tubers (the diameter of its perennial spherical stems can reach 60 cm, and the weight can exceed 100 kg) and large leaves (can be up to 3 to 4 meters long and the diameter of leaves can exceed 5 meters), it is the largest plant in the world with monomer inflorescence and the smelliest flower in the world. That's right, the flowers of the konjac look like this↓↓
The huge inflorescence shaft extends out from the half-open Buddha flame bud like an umbrella, and looks like a cloak covered with blood. Looking at the strange shape and bright colors, isn't it full of mysterious exotic atmosphere? In addition, the trolls of konjac when they bloom will release their own synthesized gas containing more than 100 chemical substances, and emit a smell of rotten meat. No wonder this magical plant was once said to be " man-eating flower " - relying on the confusing smell to attract people to its side, and then swallow it all into its stomach, and the purple-red blood soaked the leaves...
Many netizens who enjoy flowers online said they were reminded of the " corpse-scented konjac " in tomb robbery novels. (Screenshot from Weibo comment)
In fact, troll konjac does not eat people, please feel free to watch. Because the flowers of konjac are huge and consume very nutrients, their flowering period is only 48 hours. The rotten smell emitted by the konjac when it blooms is just to attract insects such as flies, scavenging beetles , and some small scavenging animals to pollinate them. It is a kind of wisdom to survive and reproduce.
Konjac will only bloom 3 to 4 times in a lifetime. Because it is extremely difficult to bloom and the flowering period is very short, few people can see the true appearance of the Konjac blossoming. In the past 100 years since its first discovery in 1878, it has only had more than a hundred flowering records around the world. This time, the konjac introduced and cultivated by the National Botanical Garden ushered in the group flowering period of three plants, which is the first time in the history of world konjac cultivation, and behind this is the efforts of scientific researchers.
"The origin of konjac is in the tropical rainforest of Sumatra, Indonesia. Its requirements for temperature and humidity are very strict, which is also a difficulty in artificial cultivation and maintenance." Wei Yu introduced that the konjac in the National Botanical Garden was introduced from a garden in the United States in 2009. Due to the great differences in the origin of Beijing and konjac, the staff specially built a small nursery for it, controlling the temperature and humidity within the range that is most suitable for its growth. "Troll konjac can be said to be very 'sweet'. The temperature range suitable for growth is very narrow and the requirements for air humidity are also very high. Especially during the flowering period, if the humidity is low, its buds will dry up, affecting the final flowering and fruiting."
In fact, the troll konjac in the National Botanical Garden has also bloomed before, but this time the group blossoms are the first time. "We have made detailed records and observations of the previous blooms, and summarized a set of technologies that promote flowering, or flowering control technologies. Now, the group blossom of konjac can basically be achieved." Wei Yu said.
hard-won fruit
realizes the group blossom of konjac, which is the "prerequisite" for the fruiting of konjac this time.
In the exhibition greenhouse of the National Botanical Garden (North Garden), the two fiery red konjac fruits are like two bright torches. (Photo by Peng Dan)
"The female and male flowers of trolls mature at different times, and in terms of it, male and female are ripened." Wei Yu introduced that this is an advanced mechanism to avoid self-intercourse decline, and it also means that only a single trolls can produce fruit when they bloom, and they can only pollinate each other and bear fruit when individuals bloom at the same time.
"This is the greatest significance of the group blossom this time. The pollen we collect from the single plants in the group blossom is pollinated downward in turn, imparting the eldest pollen to the second, and imparting the second pollen to the third, so that the second and the third will succeed and bear fruit smoothly."
close-up of the troll konjac fruit order.
In fact, in 2013, Beijing Botanical Garden (now the North Garden of the National Botanical Garden) had achieved tetraplus fruit, but at that time, white konjac pollen was used for hybridization, which only stimulated the fruit to swell and did not obtain fully mature seeds.
This time, the pollen collected from a single plant in the flowering population was pollinated downward in turn. After the flowering, the fruits swelled and colored smoothly. In August, the fruits were dissected and found obvious embryos. Subsequently, the inflorescence stalks grew rapidly and the fruits grew rapidly. Because the fruits were precious, the staff did not cut the fruit easily.
More than two months later, the staff conducted a second anatomical observation of the troll konjac fruit with anticipation. They were surprised to find that the seeds had taken shape and the seeds had developed significantly. The seeds were separated from the flesh, achieving the first troll konjac fruit in China!
"From seed to seed" process
Although it has been achieved solidity, the staff's task is far from over.
"In fact, it takes 6 to 7 months for the fruit of troll konjac to truly mature. At present, we see that the seeds are developing very well, but we have to wait until about February next year to fully mature. Only by sowing the fully mature seeds and growing new troll konjac seedlings can we truly copy its complete growth cycle."
Wei Yu said that being able to achieve a complete growth cycle of troll konjac, that is, the process from "seed to seeds", is an important symbol of the successful land protection of plants.
As the environmental destruction deteriorates, biodiversity protection has become an important issue. The botanical garden has unavoidably shouldered the important mission of plant conservation, mainly including ex situ conservation and on-site conservation. At present, there are not many species of troll konjac in the wild and are facing endangered, so extrinsic protection has become particularly important.
"The growth range of wild konjac is very narrow. It can be said that it is only distributed in the western slope rainforest of Sumatra, Indonesia. Due to the locals' reclaiming fields and cutting wood, the rainforest has been severely damaged, and the habitat of konjac has become increasingly broken." According to incomplete statistics, Indonesia has lost 72% of the original tropical rainforest, and the situation is still deteriorating. The wild survival status of konjac is in danger. It is necessary to preserve this species and study its biological learning and reproduction mechanism to find ways to increase its number. Wei Yu introduced that the main functions of the National Botanical Garden are plant exile protection, scientific research and popularization and horticulture display. As a world-class rare and endangered plant, the introduction and cultivation research of konjac is of great significance to the National Botanical Garden. "This time we have achieved fruitfulness. If the seeds can grow seedlings of konjac, this species will be able to survive in this world better. If possible in the future, we want to try to help the artificially cultivated konjac return to its native place so that it can reproduce well in the wild."
In addition to konjac, the National Botanical Garden currently collects 17,343 plants from all over the world (including the following units), including more than 1,000 rare and endangered plants. The National Botanical Garden will also display these plants to everyone one after another.
"In fact, it is not just protecting a single species, but also closely related species. The disappearance of a certain species may lead to the demise of another species. Therefore, protecting each species is also protecting our ecosystem and protecting the entire earth." Wei Yu said that he is very happy that the blossoming and fruiting of konjac this time can cause such a "sensational effect". She also hopes that people can pay attention to more cherishing endangered plants, and more people join the ranks of ecological protection.
Author: Our reporter in Beijing Peng Dan
Pictures: Except for the label, they all come from the National Botanical Garden
Editor: Lu Zhengming
