How fungi recognize (and infect) plants | Mennat El Ghalid

譯者: Marssi Draw 審譯者: Regina Chu

"Will the blight end the chestnut?

「枝枯病會奪走栗樹嗎？

The farmers rather guess not.

農人寧可猜測不會。

It keeps smouldering at the roots

栗樹的根不斷地鬱結

And sending up new shoots

並送出新枝

Till another parasite

直到另一種寄生物

Shall come to end the blight."

前來終結枝枯病。」

At the beginning of the 20th century,

二十世紀初，

the eastern American chestnut population, counting nearly four billion trees,

美國東部有將近四百萬棵栗樹，

was completely decimated by a fungal infection.

因真菌感染而全數滅亡。

Fungi are the most destructive pathogens of plants,

真菌是世界上最具 毀滅性的植物病原體，

including crops of major economic importance.

重要經濟作物也深受其害。

Can you imagine that today,

你能想像現在

crop losses associated with fungal infection

和真菌感染有關的作物損失

are estimated at billions of dollars per year, worldwide?

每年全球估計有數十億美元嗎？

That represents enough food calories to feed half a billion people.

換算成食物熱量能滿足五億人。

And this leads to severe repercussions,

真菌感染會造成嚴重的後果，

including episodes of famine in developing countries,

包含在發展中國家引起饑荒、

large reduction of income for farmers and distributors,

農夫和批發商收入大幅減少、

high prices for consumers

消費者必須高價購買，

and risk of exposure to mycotoxin, poison produced by fungi.

以及曝露在由真菌產生的 黴菌毒素的風險中。

The problems that we face

我們面臨到的問題

is that the current method used to prevent and treat

是現在用來預防和處理

those dreadful diseases,

那些致命疾病的方法，

such as genetic control, exploiting natural sources of resistance,

例如遺傳控制、 開發抵抗真菌的天然資源，

crop rotation or seed treatment, among others,

輪作或種子處理等等，

are still limited or ephemeral.

這些做的都還是有限且不夠持久。

They have to be constantly renewed.

處理方式必須不斷更新。

Therefore, we urgently need to develop more efficient strategies

所以我們迫切需要 發展更有效的策略，

and for this, research is required to identify biological mechanisms

因此研究必須能辨識出

that can be targeted by novel antifungal treatments.

能以新型抗真菌法對抗的生物機轉。

One feature of fungi is that they cannot move

真菌的特色是無法移動，

and only grow by extension to form a sophisticated network,

而且只能透過擴展生長， 進而形成複雜的網絡，

the mycelium.

稱為菌絲體。

In 1884, Anton de Bary, the father of plant pathology,

1884 年，植物病理學之父狄伯瑞

was the first to presume that fungi are guided by signals

率先提出真菌依靠訊號引導的假設，

此訊號來自它的寄主植物，

sent out from the host plant,

meaning a plant upon which it can lodge and subsist,

這意味著發訊號的植物 可以供給食宿，

so signals act as a lighthouse

所以訊號扮演像燈塔的角色，

for fungi to locate, grow toward, reach

為真菌定位、提供發展和延伸方向，

and finally invade and colonize a plant.

最後入侵並定殖於某植物。

He knew that the identification of such signals

他知道辨識出這種訊號

would unlock a great knowledge that then serves to elaborate strategy

能解開一大知識庫之謎，

之後能藉此規畫出 阻擋真菌和植物交流的策略。

to block the interaction between the fungus and the plant.

However, the lack of an appropriate method at that moment

然而，當時欠缺適合的方法，

prevented him from identifying this mechanism at the molecular level.

因此他未能在分子層級 辨識出這種機轉。

Using purification and mutational genomic approaches,

透過純化和突變基因的方式，

as well as a technique

加上一種技術，

allowing the measurement of directed hyphal growth,

能測量出被引導的菌絲生長，

today I'm glad to tell you that after 130 years,

今天我很高興能告訴大家， 在 130 年後，

my former team and I could finally identify such plant signals

我與之前合作的團隊 終於能辨識出這種植物訊號，

by studying the interaction between a pathogenic fungus

我們透過研究一種病原菌 和植物的互動，

called Fusarium oxysporum

即尖孢鐮刀菌，

and one of its host plants, the tomato plant.

和此菌的一種寄主植物 ──蕃茄植株。

As well, we could characterize

同樣的，我們也能描繪出

the fungal receptor receiving those signals

真菌用來接收那些訊號的接收器、

and part of the underlying reaction occurring within the fungus

在真菌中的部分潛在反應，

and leading to its direct growth toward the plant.

以及它朝植物直接生長的位置。

(Applause)

（掌聲）

Thank you.

謝謝。

(Applause)

（掌聲）

The understanding of such molecular processes

了解這種分子過程

offers a panel of potential molecules

能提供潛在的分子平臺，

that can be used to create novel antifungal treatments.

用來創造新的抗真菌處理方式。

And those treatments would disrupt

那些處理方式會中斷

the interaction between the fungus and the plant

真菌和植物之間的交流，

either by blocking the plant signal

透過阻隔植物發出的訊號，

or the fungal reception system which receives those signals.

或是阻隔真菌接受訊號的系統來做到。

Fungal infections have devastated agriculture crops.

真菌感染摧毀了農作物。

Moreover, we are now in an era

而且我們正處於

where the demand of crop production is increasing significantly.

需要大幅提升糧食產量的時代，

And this is due to population growth, economic development,

以因應人口成長、經濟發展、

climate change and demand for bio fuels.

氣候變遷和對生物燃料的需求。

Our understanding of the molecular mechanism

我們對分子機轉的了解，

of interaction between a fungus and its host plant,

對真菌和寄主植物之間的互動，

such as the tomato plant,

例如和蕃茄植株之間的互動，

potentially represents a major step towards developing more efficient strategy

可能是很重要的關鍵，

讓我們能發展更有效的策略 來抵抗植物的真菌病，

to combat plant fungal diseases

and therefore solving of problems that affect people's lives,

進而解決影響人類生活的問題、

food security and economic growth.

糧食安全和經濟成長的問題。

Thank you.

謝謝。

(Applause)

（掌聲）