Agdia, Inc.

10/31/2026

What problems do potato growers large and small face in Africa and the rest of the world? Our joint team from Agdia-EMEA in France and Agdia HQ in the USA were in Kenya this week to find out.

From disease challenges like bacterial wilt, soft rot and blackleg to logistical issues and beyond, we learned a lot and will share more over the coming weeks.

In addition to learning about potato production challenges, our team shared several technologies growers can use in the field to test for bacteria, viruses and fungi that threaten potato yield and quality.

10/15/2026

Tomato leaf curl New Delhi virus (ToLCNDV-ES) turned up in southeastern France in 2020, then again in 2022.

A team at INRAE sequenced 48 French isolates collected between 2020 and 2024 and compared them against 110 Mediterranean references. The French isolates are polyphyletic within the Mediterranean clade, pointing to multiple independent introductions.

The same virus groups reappearing in France year after year suggests the virus is persisting locally rather than being reintroduced each season. Populations found in weeds matched those found in crops, making Datura stramonium (aka thornapple or jimsonweed) and Ecballium elaterium (squirting cucumber) likely reservoirs.

The work used Oxford Nanopore long-read sequencing with rolling-circle amplification, processed through Genome Detective, which replaced the cloning and Sanger work this kind of study used to require. The team also built a ToLCNDV subtyping tool that is now part of that platform.

Credit to Dr. Cécile Desbiez, Dr. Eric Verdin, and Dr. Adriana Patthamapornsirikul at INRAE Pathologie Végétale, with Victor Golyaev and colleagues at KU Leuven, under the EU Virtigation project.

See more info in this article (also image source): https://hubs.li/Q04Bk7Z60

10/08/2026

Bacterial blackleg is primarily a tuber-borne disease in potato. Infected seed is the main source of inoculum, so starting with tested, clean seed is extremely important to avoid downstream losses.

A recent article in Growing Produce lays out some of the difficulties in identifying and managing this disease in potato.

Blackleg is caused by bacteria in the genera Pectobacterium and Dickeya, and the two behave differently:

Dickeya is most aggressive in warm conditions and can move fast through stem tissue, causing sudden wilt and plant death.

Pectobacterium moves slowly, causes milder symptoms in emerged plants, and is more likely to show up as tuber rot in storage or seed piece rot in the soil.

If infection is not caught before planting, molecular diagnostic methods are still important for distinguishing which species is present, which helps explain an outbreak after the fact and informs where seed gets sourced next season.

Here is the full article and image source by Carrie Huffman Wohleb at Washington State University: https://hubs.li/Q04zB2d00

09/30/2026

Agriculture border control specialists at George Bush Intercontinental Airport in Houston recently intercepted a plant pathogen that had never been detected at a U.S. port of entry.

The find came from baggage belonging to a traveler arriving from New Zealand. Eucalyptus leaves showing signs of disease were pulled, sampled, and sent to USDA plant pathologists, who identified the pathogen as Davisoniella eucalypti. If established in the U.S., it could cause severe defoliation and reduced growth rates in eucalyptus, with consequences for both timber and ornamental nursery operations.

It’s worth noting how this was caught: A specialist saw symptoms on the leaves and acted on them. That works when symptoms are present, which is not the usual case.

Latent infections, low-titer material, and asymptomatic carriers all move through inspection looking perfectly healthy, and a pathogen that has never been seen in a country has no local baseline of what its symptoms look like in the first place.

Advanced, accessible diagnostic methods are built to cover this gap. Rapid molecular testing with validated methods lets inspection programs screen asymptomatic material, confirm suspect finds faster, and generate documented results.

More info here: https://hubs.li/Q04yk8nK0

09/25/2026

There is no cure for banana bunchy top virus (BBTV). Once a plant is infected, it must be destroyed. The virus moves through the mat into every sucker. Clean planting material is the only way forward, which puts the burden on early detection.

Around 2017, banana growers on Oʻahu were facing BBTV and Panama wilt together. University of Hawaiʻi CTAHR Extension secured a Specialty Crop Block Grant through the Hawaiʻi Department of Agriculture and went to work.

Jensen Uyeda screened field-grown banana plants for BBTV using Agdia's AmplifyRP XRT rapid DNA amplification assay, which CTAHR describes as an improvement over ELISA for this work. Extension then partnered with Dr. Ming Li of the Hawaiʻi Agriculture Research Center and the East Hawaiʻi County Farm Bureau to move BBTV-free plants into tissue culture for multiplication, alongside a rotational insecticide program to keep the aphid vector out.

875 tissue-cultured plants reached 22 growers. A follow-on grant funded 5,000 to 10,000 more for statewide distribution. Clyde Fukuyama of Kahuku Farms, who had been close to dropping apple banana for lack of clean planting stock, said the program would let them start increasing plantings again.

The detection step is where these programs succeed or fail. An infection missed in early screening does not just stay in one plant. It goes into tissue culture and gets multiplied thousands of times over, which is why nucleic acid amplification is the right tool for verifying clean stock rather than antibody-based methods.

Credit to Jensen Uyeda, Amjad Ahmad, Koon-Hui Wang, Jari Sugano, and Dr. Ming Li.

It was less than four years ago when our banana industry was reeling from the double punch of Panama Wilt and Bunchy Top Virus. With the value of their product in freefall, Oʻahu farmers reached out to Extension. In response, Amjad Ahmad, Koon-Hui Wang, and Jari Sugano obtained a Specialty Crop Blo...

09/11/2026

Plant-pathogenic bacteria are some of the most widespread and economically significant pathogens in agriculture.

The Pseudomonas genus consists of nearly 350 bacterial species, including highly host-specific pathovars like Pseudomonas syringae. These pathogens can cause many different symptoms across various fruits, vegetables, grains, ornamentals, and cannabis:

- blights
- cankers
- dieback
- leaf spots
- flower blast

Early detection is often the difference between a contained issue and a season-long setback.

Agdia's ImmunoStrip® for Pseudomonas spp detects a wide range of phytopathogenic Pseudomonas species and pathovars, including those affecting tomato, pepper, cucurbits, crucifers, beans, soybeans, cannabis, woody ornamentals and more.

Technical info including a full validation report can be found here: https://hubs.li/Q04xh1st0

09/04/2026

Here's a nice writeup by Bracken Henderson (University of Idaho Extension) about Watermelon mosaic virus (WMV).

Disease symptoms caused by this aphid-transmitted potyvirus can resemble many other cucurbit-infecting viruses in addition to other abiotic disorders such as nutrient deficiencies.

See here for more info:

This has been a year to make a gardener proud. The sweet corn is tall and tasseled. Bush beans are lush and loaded. Kale, collards, and Swiss chard have never looked more vigorous. Cucumbers, zucchini, okra, carrots, and potatoes are producing beautifully. In fact, the garden is doing so well that i...

08/28/2026

Well this certainly isn't a tomato. It isn't even a dicot.

Check out this recent LinkedIn post by Debi Groth-Helms highlighting a report on a new host of Tomato brown rugose fruit virus (ToBRFV): Asiatic dayflower (Commelina communis)

📣 ToBRFV natural host range expanding 📣 Now found in Commelina dayflower, a monocot.

08/21/2026

Here's an interesting investigation into lettuce disease symptoms out of the UC Cooperative Extension office of Monterey County in Salinas, California:

Impatiens necrotic spot virus (INSV) was originally suspected, but the plants tested negative for INSV in addition to negative results for Tomato spotted wilt virus (TSWV) and the usual bacterial and fungal suspects.

More info on the case here: https://hubs.li/Q04tRsfc0

08/14/2026

Tar spot continues to spread in the Midwest. States where the disease has been reported so far this year include Georgia, Indiana, Illinois, Iowa, Kansas, Kentucky, Michigan, Minnesota, Missouri, Nebraska, New York, Ohio, Virginia, and Wisconsin.

Tar spot is a fungal disease in corn caused by Phyllachora maydis. Initial symptoms include dark flecks/lesions and chlorosis (yellowing) on leaves. Symptoms can eventually progress to early leaf drop and reduced kernel yield.

More info here, including a map of current disease status in the US provided by the Crop Protection Network: https://hubs.li/Q04t4K5p0