I can see clearly now: A new method for rapid detection and identification of downy mildew in basil

Jul 16, 2013
I can see clearly now -- A new method for rapid detection and identification of downy mildew in basil
A basil leaf infected with Peronospora belbahrii shows differential staining of sporangioshores bearing elliptical sporangia. Credit: Image courtesy of Koroch et al.

Downy mildew (Pernospora belbahrii Thines) is a relatively new disease to North America. First reported in 1933 in Uganda, downy mildew has spread rapidly across the globe. Early detection of downy mildew is crucial for control of the disease, which can devastate both greenhouse and field basil crops. However, the signs and symptoms of basil downy mildew can be difficult to differentiate from those caused by environmental stresses such as nutrient deficiency. As part of an ongoing project to develop downy mildew–resistant plants, researchers at The City University of New York and Rutgers, The State University of New Jersey, have developed a novel procedure that enables early detection and identification of downy mildew in basil.

Removing the need for expensive equipment and complicated protocols, lead author Professor Adolfina Koroch and colleagues describe their method for detecting basil downy mildew in the July issue of Applications in Plant Sciences.

"Our protocol will be really important to help prevent the further spread of the disease," said Koroch. "This staining method will allow for quick identification of the pathogen at the early stages of the infection cycle. With this information, timely disease control measures can be taken so the pathogen spread can be diminished."

Using fresh , samples are rapidly cleared of their cellular contents with a proprietary new formulation called Visikol™. Visikol was first published in the May issue of Applications in Plant Sciences, where Koroch, along with graduate student Thomas Villani and Professor James Simon, demonstrated that the new solution is an effective substitute for the controlled substance chloral hydrate. Once cleared, tissue samples are stained and examined.

"What is so useful about this staining technique is that now downy mildew can be detected using a hand magnifying glass," said Villani. "Putting this protocol into practice, we are really excited about the effect that this will have on people in the industry, who often have to rely on macroscopic techniques."

This technique will allow growers, breeders, disease managers, county agents, and other labs to confirm the disease more rapidly so other can be properly instituted. Expediting the diagnosis of basil downy mildew will facilitate rapid and appropriate control strategies that can be used to prevent disease epidemics and to help gardeners, growers, and educators alike in the proper identification of the pathogen. Although Koroch and her colleagues focused on the identification of basil downy mildew, they expect that their rapid staining protocol will aid the detection of other pathogenic organisms that cause disease outbreaks in other economically important plants.

"Science should be useful and translational," said Simon. "And that's exactly that this protocol allows us to do."

Explore further: Battling superbugs with gene-editing system

More information: www.bioone.org/doi/pdf/10.3732/apps.1300032

add to favorites email to friend print save as pdf

Related Stories

Sexual reproduction only second choice for powdery mildew

Jul 14, 2013

Powdery mildew is one of the most dreaded plant diseases: The parasitic fungus afflicts crops such as wheat and barley and is responsible for large harvest shortfalls every year. Beat Keller and Thomas Wicker, ...

Recommended for you

Battling superbugs with gene-editing system

11 hours ago

In recent years, new strains of bacteria have emerged that resist even the most powerful antibiotics. Each year, these superbugs, including drug-resistant forms of tuberculosis and staphylococcus, infect ...

For legume plants, a new route from shoot to root

Sep 19, 2014

A new study shows that legume plants regulate their symbiotic relationship with soil bacteria by using cytokinins—signaling molecules— that are transmitted through the plant structure from leaves into ...

Controlling the transition between generations

Sep 18, 2014

Rafal Ciosk and his group at the FMI have identified an important regulator of the transition from germ cell to embryonic cell. LIN-41 prevents the premature onset of embryonic transcription in oocytes poised ...

User comments : 0