Top Crop Manager

Root scanning technology reveals key factors in crop health

Root scanning is a modern technique...

March 10, 2008
By Dr. Ravi Ramachandran*

Root scanning is a modern technique that enables researchers to conduct
extensive evaluations on root structures. At Syngenta, this technology
is being applied for the first time to crop health. Researchers are
using it to detect diseases in plants and determine the effectiveness
of seed treatments.

Effects of Apron Maxx RTA on peas: untreated (top) vs treated (bottom). The effects of a seed treatment such as Apron Maxx RTA is demonstrated in an analysis of pea roots.

To-date, most field biology research has focussed on plant health above
the soil, rather than the root structures below. Yet, roots are an
essential part of a plant’s health. They must contend with various
threats, such as seed and soilborne disease and insect pests, in order
to absorb nutrients and water and support healthy plant growth. A
thorough understanding of plant roots is critical to developing
products that help grow healthy crops.

Research at Syngenta has shown a strong correlation between the fresh
weight of seedlings and root morphology, which indicates that a healthy
root system is the foundation for a healthy plant. With root scanning
technology, researchers are finally able to carefully examine the plant
below the soil. This is revealing new insights about the importance of
root health, the impact of pests on root development and most
importantly, how to fight these challenges with the right seed care

How does root scanning work?
The root scanner is an image analysis system designed for root
evaluation. It measures morphological features such as root length,
surface area, volume and average diameter. Finer root architectural
details including the characteristics of the secondary root, such as
the number of branches and development of root hairs, may also be
studied in detail.

In a typical study, seeds first germinate either in the field or in a
laboratory. One to three weeks after planting, the emerged plant is
extracted from the ground with the growing
root intact. Following a thorough wash, the plant is put in a
transparent tray containing water and placed on the root scanner. The
scanner produces an image of the plant root and using the appropriate
software, the researcher evaluates various root development parameters.

What can be learned from root scanning?
During the past two years, the root scanner system has proved to be a
powerful tool for measuring the effect of seed care products on crops
such as corn, soybeans, dry beans and pulse crops. As a result,
Syngenta researchers have been able to quantify the impact of seed care

For example, root scanning makes it possible to analyze the forks in
plant roots, which are essential to anchoring the plant in the soil and
establishing a healthy plant stand. Using root scanners, Syngenta researchers found that peas treated with Apron Maxx
RTA seed treatment exhibited a 92 percent increase in root branching
relative to untreated seeds.

Studies also revealed that plants germinating from pea seeds treated
with Apron Maxx yielded roots 15 percent longer and with 17.5 percent
more surface area than untreated pea seeds.

Even more importantly, further research revealed that these healthy
roots translated directly to greater yields. In replicated trials,
untreated seeds yielded 55bu/ac, while seeds treated with Apron Maxx
yielded 61.5bu/ac. Seeds that were treated with both Apron Maxx and an
inoculant yielded 64.6bu/ac.

What does this mean for growers?
By providing measurable results of seed care treatments, root scanning
technology can help growers make more informed choices and better
define their expectations when it comes to selecting and using seed
care products. This technique will help Syngenta continue to develop
products that promote healthy roots and plants. Given the link between
root health and high yielding crops, root scanning technology will be a
valuable research tool for the industry in the years ahead. -end-

*Dr. Ravi Ramachandran is manager of product chemistry and chemical services with Syngenta Crop Protection Canada.