Did the jujube tree at the netizen's grandmother's house suddenly go "crazy"? Is it contagious? The truth is actually like this!

Recently, many people have seen a video: a netizen took a photo of an abnormal jujube tree at his grandmother's house and asked everyone what was going on?

Source: Internet

So, many people left comments in the comment area saying that this jujube tree has gone "crazy"... What, a jujube tree can also go "crazy"? And it is said that "going crazy" is contagious, and before you know it, all the jujube trees in the jujube orchard have gone "crazy".

Source: Internet

Why did the jujube tree go crazy? Was it, as the comments said, that it was mad at people’s behavior—“the jujube tree didn’t eat the fruits in time, so it thought people disliked its taste and went crazy”; or was there another reason for the jujube tree to go crazy?

The jujube tree is not " going crazy ", but has "cancer"

When many people hear the word "crazy", they naturally think of human "craziness", so there is a rumor that the jujube tree is driven "crazy" by anger.

In fact, it is impossible for a jujube tree to "go crazy" like humans. Although in recent years, there are many researchers who believe that plants can communicate, they are not capable of such complex emotional changes as "going crazy".

The " madness " of the jujube tree is actually a disease caused by phytoplasma infection.

Phytoplasmas are a type of bacteria that parasitize plants and some insects. According to current research results, phytoplasmas cause diseases in more than 1,000 plant species in 98 families worldwide. In addition to jujube trees, the familiar celery, onions, carrots, paulownia trees, apple trees, apricot trees, grapes, coconuts, etc. are all among the victims.

When plants are parasitized by phytoplasmas, their original growth and development process will be tampered with. The most common symptom is the crazy growth of branches and leaves, with many branches growing from just one point, so this phenomenon is also called witches' broom. Because the appearance of witches' brooms is like the brooms ridden by witches in medieval stories, it is also known as "witch's broom".

In addition to arbusculinization, there are a series of diseases such as flower-leaf change, leaf yellowing, fruit rot, and dieback, which will greatly affect the yield of crops and even endanger the survival of crops. Therefore, this type of disease is also called the "cancer" of plants.

Take the jujube madness disease as an example. Jujube trees infected by the phytohormone will first sprout a large number of buds on the infected branches and roots, and then grow into clusters of messy branches that are different from other branches at first glance.

Source: References

When the phytoplasma infects the flower buds, the date tree will no longer bloom. The original petals and sepals will gradually develop into leaflets as the disease worsens. The nutrients of the already formed disc, ovules, anthers and other parts will also be absorbed by the leaflets until the entire flower withers.

At this stage, the branches of the jujube tree are in a state of "no interest in reproduction, only wanting to grow and be beautiful". Even if the healthy branches are not infected, the fruits that are barely produced will become crooked, uneven in size and color, and the flesh will be cystic, and the sweetness will disappear, making it impossible to eat.

The " crazy " jujube tree will die in 3 to 5 years.

The impact of phytoplasma infection on the date tree seems to be simply that it loses the reproductive qualifications to bloom and bear fruit. So can the tree still survive?

In fact, the " crazy " jujube tree will not live for many years. The diseased jujube tree will go through the leaf change period, flower change period, withering period, madness period, and tree death period. After about 3 to 5 years, when the disease spreads from the local area to the whole plant, the jujube tree will die completely.

The spread of the jujube madness has and is posing a huge threat to China's jujube planting. Many jujube orchards have been destroyed due to the spread of the jujube madness.

In the early 1970s, the jujube orchards in the Xiaozao production area of ​​Miyun, Beijing were destroyed because of this. In the 1980s, the disease spread to Neihuang, Qixian, and Weixian in Henan, causing serious danger to many acres of jujube orchards. Due to the rapid development of the disease, it took only three years for the disease to go from sporadic cases to 30% of the fruit trees in Neihuang.

Of course, the jujube madness can be cured. In the early stage of the disease, it can be treated by cutting off the diseased branches, infusion, etc. However, since the jujube madness is contagious, it is quite difficult to cure it in the orchard.

How is the date madness disease transmitted?

The disease is naturally spread by phytoplasmas. However, plants cannot walk, and neither can phytoplasmas, so how is the disease transmitted? The problem lies in some insects that feed on the sap of the date tree.

Phytoplasmas are mainly found in the phloem of plants, which is the complex transport, storage and transportation of nutrients in plants. This is also easy to understand. Phytoplasmas parasitize plants in order to find a canteen where they can eat for a long time. Since they have entered the house to eat, they naturally live in the most convenient place to eat and drink, which is the phloem.

Some insects also like to suck the sap from the phloem of plants. During the meal, the phytoplasma quietly transferred from the cafeteria to other diners, the leafhoppers . As the leafhoppers sucked the sap from plant to plant, the phytoplasma took advantage of the easterly wind to spread to other plants around the diseased plants. This process is very similar to mosquitoes carrying malaria, which spread malaria among people by sucking blood.

Source: References

Moreover, the phytoplasma that causes jujube madness (16SrV-B subgroup phytoplasma) can also parasitize cherry trees, ailanthus, persimmon trees, vitex, sedge, elm trees, etc. in the fields, so once the disease starts, it will spread from the jujube trees to many other surrounding plants as well.

This is also the purpose of phytoplasmas infecting plants. On the one hand, they transform plants so that their nutrients are no longer used for flowering and fruiting, but are continuously supplied to themselves; on the other hand, they take advantage of the flight of leafhoppers to parasitize in more plants and achieve wider spread.

Today, although the date madness disease still exists, researchers are constantly studying the changes that occur in the process of phytoplasma infection in plants, trying to solve the "madness" of plants from the root. At the same time, they are also constantly breeding more new disease-resistant varieties to cope with the ever-spreading phytoplasmas.

Although the lack of cell walls and the inability to culture phytoplasmas in vitro pose a great challenge to research work, it is believed that researchers will still be able to find better solutions in the future to help date trees overcome the terrible "mad" disease.

References

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[2] Wang Xi, Hou Ruyue, Huo Liyong, Meng Xiaoxin, Wang Xiaoling, Wang Yanli & Mao Yongmin. (2024). Investigation on the incidence and control technology of jujube madness in Hebei Province. Hebei Agricultural Sciences (01), 55-59+65.

[3] Lin Jian & Sun Chao. (2024). Occurrence and prevention of jujube madness. Yantai Fruit Trees (01), 47-48.

[4] Wang Xiaoyan, Zhang Rongyue, Li Qinghong, Li Jie, Li Yinhu, Shan Hongli... & Huang Yingkun. (2023). Research progress on the status, distribution and diversity of phytoplasma diseases in China. Acta Agronomica Sinica (03), 58-64.

[5] Chen Yuxin, Zhang Yuxi, Liu Ruichang, Li Linlin, Li Chunqin, Li Boliao & Li Guangwei. (2023). Investigation on the occurrence and damage of jujube madness, jujube fruit cracking disease and peach borer in northern Shaanxi. Plant Protection (01), 317-327+345. doi:10.16688/j.zwbh.2021603.

[6] Yan Xiongfei, Zhang Quan, Zhang Peng, Liu Qingzhao, Hao Zhe, Li Gang & Liu Yonghua. (2022). Potential risk analysis and management strategies of jujube madness in Shaanxi Province. Journal of Biosafety (03), 262-267.

[7] Wang Xiaoyan, Zhang Rongyue, Li Jie, Li Yinhu, Li Wenfeng, Shan Hongli & Huang Yingkun. (2021). Research status, distribution and diversity of phytoplasma diseases in China. (eds.) Plant pathology technology innovation and green control - Proceedings of the 2021 Annual Conference of the Chinese Society of Plant Pathology (pp. 697). Yunnan Key Laboratory of Sugarcane Genetic Improvement, Sugarcane Research Institute, Yunnan Academy of Agricultural Sciences;

[8] Geng Xiansheng, Shu Jinping, Wang Haojie & Zhang Wei. (2015). Research progress on the transmission, prevalence and control of phytoplasma diseases. Chinese Agricultural Science Bulletin (25), 164-170.

[9] Zhao Jin, Liu Mengjun, Dai Li & Zhou Junyi. (2006). Study on the changes of endogenous hormones in jujube trees infected with jujube madness. Chinese Agricultural Science (11), 2255-2260.

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Planning and production

Author: Science Popularization Team of Xinshi Science Popularization Studio

Reviewer: Tao Ning, Associate Professor, Institute of Biophysics, Chinese Academy of Sciences

Planning丨Yinuo

Editor: Yinuo

Proofread by Xu Lai and Lin Lin