Existence of Mexico's Pathogen That Causes Clubroot Disease of Crops Like Cabbage and Kale Confirmed

Clubroot disease has long been thought as a subject of speculation or anecdotal evidence only.

However, a new study confirmed the existence of Mexico's pathogen Plasmodiophora brassicae that causes the deadly plant disease affecting crops like cabbage and kale.

The unprecedented discovery highlights the aversion of a potential global plant pandemic affecting some of the world's plant species.

Cruciferous crops suffer from the disease, characterized by abnormally larger-than-normal roots.

This subject has been noticed by scientists and online databases for several years. Now, the new research led by researchers from the American Phytopathological Society affirmed the existence of the elusive pathogen, which also affects broccoli and other crops, in addition to those mentioned earlier.

Mexico is considered to be the 5th large broccoli producer and main exporter to the eastern US and Canada.

The study's author hopes their findings may not only prevent potential outbreaks but also protect agricultural crops and help agronomic methods to combat the notorious crop disease.

Clubroot Disease

The breakthrough discovery was published in the journal Plant Disease on July 8.

In the new paper, the research team applied a detection methodology previous used amid the COVID-19 pandemic.

The method involves the scientists working with local cruciferous crops growers in the Central American country, where they collect soil samples from different field categories, including those with or without cruciferous crops.

What is Plasmodiophora Brassicae?

Plasmodiophora Brassicae is a "root-infecting protist pathogen" which specifically cause the clubroot disease to the brassica species.

Unlike other pathogens, such as bacteria and viruses, P. Brassicae lives in the soil and contains spores that can survive for over 15 years, according to the online database platform CABI.

The spread of the so-called "motile zoospores" virus take place under wet conditions and the movement of infested soil, affecting a wide range of plants in the brassica family including several weed species.

A zoospore is known as an asexual spore that can move and spread on its own using a flagellum.

Also called as a swarm spore, P. Brassicae are also created by some bacteria, fungi, and protists.

Fungal Plant Disease

The fungal disease affects other plants like radish, mustard, and ornamentals like candytuft, according to the Missouri Botanical Garden.

Clubroot belongs to the genus Plasmodiophora, family Plasmodiophoraceae, and kingdom Protista, which are eukaryotic organisms that are not classified as animals or plants.

The pathogen received its name due to its club-like shape when infecting the roots of plants.

If zoonotic diseases, which pertain to animal to human transmission of illnesses, result in evident or subtle symptoms, the same is the case for plant diseases.

For the clubroot disease, the Missouri Botanical Garden says the initial symptom would be a yellowish color for older leaves, which looks "stunted" and will eventually die.

The said symptom is in addition to the roots' club-like appearance or enlarged roots, which causes the plant to experience drought-like symptoms.

The bloated roots will prevent the plant's ability of water absorption from the soil, which will be the onset of the gradual death.