Detection and Management Tools for Low Falling Number in the ‘Grain Chain’
Funded by the Foundation for Food and Agriculture Research (FFAR), this project is a widespread collaborative effort between university researchers, industry partners, nonprofits, and growers. Together, we are working to develop and validate tools, including a wheat quality test, that are more accessible to the wheat industry.
On this webpage you will find links to information about the work being done on this project, including popular press articles, research articles, extension articles, podcast interviews, and more! We will be releasing regular updates about the status of the development and testing of the rapid test, as well as education and outreach efforts.
Why is this important?
Worldwide, the wheat industry experiences substantial financial losses due to low falling number (FN), and the frequency of low-FN events is increasing. The FN test is the standard in the industry, but it is slow and uses expensive and bulky equipment that makes it unrealistic to run on-farm. A less expensive and more mobile-ready testing setup is a great supplement that opens the door to opportunities for earlier testing. Testing on-farm or at elevators will minimize disadvantageous mixing of sound and unsound grain, and the speed of testing will be helpful to breeders who have many lines to test.
Project Goals
- Develop rapid tests such as immunoassays (visualize a COVID test or pregnancy test) that will accurately measure alpha-amylase activity and other targets that more accurately predict falling number.
- Validate the performance of these assays across a variety of market classes, growing environments, and testing environments.
- Use proteomics studies to discover distinct protein markers between late-maturity alpha-amylase (LMA) and preharvest sprouting (PHS), and use these for development of next generation tests that distinguish between the two. This is important because LMA may have less of an impact on end-use quality than PHS. Our long-term goals are to provide the industry with tools that:
- Breeders will use to breed more effectively for LMA and PHS tolerance.
- Facilitate separation of LMA-impacted grain from PHS-impacted grain earlier in the grain chain.
- Allow for a deeper understanding of LMA and PHS causes and physiology.
- Develop weather models to predict periods of high risk for LMA or PHS events.
Causes of Low Falling Number
There are four known causes of low falling number in the Pacific Northwest. Low falling number (LFN) in wheat can cause downstream product quality issues that result in significant economic losses for producers.
Green kernels
Green kernels have a high risk of causing low falling number. A little goes a long way with green kernels. Just a few green kernels can reduce the falling number for an entire grain lot. Waiting until all kernels are fully ripe before harvest is the best as there are no post-harvest management options for green kernels.
Preharvest sprouting (PHS)
Preharvest sprouting brings a high risk of causing low falling number. PHS is caused by moisture after the grain has matured before harvest has been completed. Black point and visible sprouting are two signs of PHS damage, although damage may not be visible. Growing tolerant varieties is the best management option to reduce preharvest sprouting.
Late-maturity alpha-amylase (LMA)
Late-maturity alpha-amylase has a moderate risk of causing low falling number. LMA is caused by a cold shock at the soft dough stage of grain development and shows no visible signs of damage. Growing tolerant varieties is the best management option. Delaying harvest (when no rain is in the forecast) and storing grain post-harvest can improve the LMA-impacted grain over time.
Non-alpha-amylase induced low falling number (NAIL)
Non-alpha-amylase induced low falling number brings a moderate to low risk of causing low falling number. NAIL is caused by stress early in grain development shortly after anthesis is complete. There are no obvious signs of NAIL, however low protein content, 8% or less, is common with NAIL. Growing tolerant varieties is the best management option. Post-harvest blending may be an option since NAIL does not have high alpha-amylase.
Rapid Test Instructional Video
In the
Journal Articles
Crop Science
Exploring preharvest sprouting (PHS) and late-maturity alpha-amylase (LMA) in wheat through proteomics: A review.
Overview: A review of proteomic approaches for identifying proteins involved in LMA and PHS.
Food Energy and Security
Harnessing enviromics to predict climate-impacted high-profile traits to assist informed decisions in agriculture
Overview: A predictive tool for low falling number was created using weather and environmental data.
Crops & Soils
A Simple Test for Determining Late-Maturity Alpha-Amylase Susceptibility Window in Wheat
Overview: This article discusses when and how late-maturity alpha-amylase is caused in wheat and the how to detect the window of susceptibility.
FFAR Extension and Media
Warm weather, healthy wheat crop keep falling number hotspots low
Capital Press, August 26, 2025
Falling Numbers Rapid Immunoassay Completes First Field Season of Testing
Overview: A rapid immunoassay for predicting falling number in wheat has been developed and is undergoing validation after testing has been run on over 2,000 samples across the Pacific Northwest.
A New Project Aimed at Combating Low Falling Numbers
Overview: Announcing the development of a new rapid test to predict falling number in wheat.
Reaching a New Landmark. The Development of a New Diagnostic Test to Manage Low Falling Numbers Post-Harvest
Overview: The road to developing a new immunoassay to supplement the falling number test.
Where Do We Go From Here?
Overview: The conclusion of the three-part series: addresses improvements in management, provides updates about the development of new tools for low falling number detection, and emphasizes the importance of variety selection.
From Elevators to Export Terminals. Following the Management of Low Falling Numbers throughout the ‘Grain Chain’
Overview: This article describes the logistics of managing sound and low falling number grain at elevators and provides an overview of how wheat moves through the grain chain through to export.
A Falling Numbers Fact-Finding Mission
Overview: This article discusses the purpose and history of managing falling number, as well as what causes low falling number.
Wheat Beat Podcast Episodes
Related Journal Articles
Development of Novel Monoclonal Antibodies to Wheat Alpha-Amylases Associated with Grain Quality Problems that are Increasing with Climate Change
Overview: Three antibodies were developed that can detect alpha-amylase; this may be useful in the development of immunoassays that differentiate between preharvest sprouting and late-maturity alpha-amylase.
Streamlined Alpha-Amylase Assays for Wheat Preharvest Sprouting and Late maturity Alpha-Amylase Detection
Overview: A 96-well Phadebas assay was shown to be effective at detecting alpha-amylase in wheat; various grinding methods were compared and found to be equally effective.
As the Number Falls, Alternatives to the Hagberg-Perten Falling Number Method: A Review
Overview: A comprehensive review of current methods for identifying low falling number, as well as future potential alternatives.
Late maturity α-amylase (LMA): exploring the underlying mechanisms and end-use quality effects in wheat
Overview: This is a current review of what’s known about LMA and identifies several key gaps in knowledge for future research.
Contact
Share the news and provide us with your feedback! We aim to foster reciprocal relationships with people from all links of the grain chain (growers, warehousemen, elevator operators, seed sellers, and other industry stakeholders) through education, outreach, and receiving feedback on what is most important to our end users. Education efforts will include information about the differing impacts of LMA and PHS on grain quality and providing training for the next generation of wheat professionals.
Primary principal investigator (PI):
