Researchers have developed a new technique that uses microneedle patches to collect DNA from plant tissues in just one minute, rather than the hours needed for conventional techniques. DNA extraction is the first step in identifying plant diseases, and the new method holds promise for the development of on-site plant disease detection tools.

"When farmers detect a possible plant disease in the field, such as potato late blight, they want to know what it is right away. Rapid detection can be important for addressing plant diseases that spread quickly," says Qingshan Wei, an assistant professor of chemical and biomolecular engineering at North Carolina State University and co-corresponding author of a paper on the work.

"One of the obstacles to rapid detection is the amount of time it takes to extract DNA from a plant sample, and our technique provides a fast, simple solution to that problem," Wei says.

It is quoted Jean Ristaino, William Neal Reynolds Distinguished Professor of Plant Pathology at NC State and co-corresponding author of the paper as saying: "Some plant diseases have similar leaf symptoms, such as late blight caused by the famed Irish famine pathogen Phytophthora infestans, and Phytophthora blight caused by a sister species P. nicotianae. The gold standard for disease identification is a molecular assay. Our new technique is important because you cant run an amplification or genotyping assay on strains of P. infestans, or any other plant disease, until youve extracted DNA from the sample."

A farmer or researcher can apply the microneedle patch to a plant they suspect is diseased, hold the patch in place for a few seconds, then peel it off. The patch is then rinsed with the buffer solution, washing genetic material off of the microneedles and into a sterile container. The entire process takes about a minute.