New online tool enables growers to diagnose strawberry problems

Scientists and IT developers at North Carolina State University are creating an online diagnostic tool that will assist strawberry growers in determining and resolving crop-related issues.

Starting June 30 strawberry growers will have a new online diagnostic tool to help them identify problems they may encounter with their crops. As part of the National Strawberry Sustainability Initiative grant, which is funded by the Walmart Foundation, a group of North Carolina State University scientists and extension IT developers
are creating a web-based interactive diagnostic key for growers. It will have application to both outdoor- and indoor-produced strawberries throughout the United States.

The key will be accessible through users’ computers, tablets and smart phones. It will be available through the North Carolina Cooperative Extension Strawberry Growers Information website.

A holistic approach

Brian Whipker, professor of floriculture–research and extension, who heads up the project, said the key
is based on attributes.

“There are 21 insect pests, 26 diseases, 14 nutritional disorders and 26 physiological disorders in the key,” Whipker said. “It covers the primary sources of problems. The herbicide damage probably won’t have application to greenhouse production, but almost everything else, including the diseases, nutritional disorders, and most of the physiological disorders and insects will apply.
“When users log onto the website there is a filter on the left side of the homepage that is based on four categories (insect, disease, nutritional and disorder) that they can sort by. The term physiological was replaced by the word disorder.”
A user can click on the insect category and receive all 21 insect pests.
“If the users don’t want to search by type then they can choose differentials based on leaf condition that has 12 options or leaf color that has 10 options,” Whipker said. “They can also search by leaf location, which has six options. Fruit conditions have eight options, including size, texture and color. There are also attributes for root and crown problems.”

The strawberry diagnostic tool being developed at North Carolina State University covers 88 different attributes, including nutritional disorders such as boron toxicity (top) and iron deficiency (bottom).
Filters narrow problem identification

Whipker said the key allows users to narrow down the problem identification by using a series of filters.

“If a grower has interveinal chlorosis, the key can filter the problem down to 12 options,” he said. “The grower can add another filter for mature leaves, which narrows the choices down to four options. The key then filters for a combination of interveinal chlorosis and mature leaves.
There are other characteristics that are listed and the grower can read down that list and sort the problem cause from there. There is one thumbnail photo of each problem that the user can choose from.”
There are different headers for each of the four categories. For diseases there are headers for causal agents including the scientific names. The headers for nutritional disorders include Problem (i.e., iron deficiency); Symptoms (with photographs and a listing of similar problems like mimics); Additional Information; Diagnostic Tips; Corrective Measures and Management.
Whipker said once a grower chooses what he thinks is causing the disorder, he can click on the problem and is taken to a fact sheet.
“There are 88 attributes and there is a fact sheet on each one,” he said. “Most of the fact sheets are two pages long. Some of the disease fact sheets are four to six pages. There are also some hyperlinks for other online resource publications that are available.”
Additional crop information

Whipker said the key template that was used for the strawberry diagnostic tool would have application to other crops.

“Diagnostics are my driving force,” he said. “I have invested $20,000 in a system that can induce nutrient disorders. I’d like towork on the nutrient disorders of greens and herbs. Currently there is no diagnostic key available for herbs.”
Whipker has also produced a nutrient disorder guide for tomatoes, “Tomatoes: Troubleshooting Guide to Nutritional Disorders”.
N.C.  State University horticulture professor Brian Whipker has released a book on tomato nutrient disorders that were greenhouse-induced.

“We produced an iPad-based book for the tomato disorders,” he said. “It is also available as a print-on-demand book at Lulu.com.

“The tomato disorder publication is more applicable to greenhouse tomatoes than field-grown. All of the tomato nutrient disorders were greenhouse-induced. A field-based system is more forgiving. With a hydroponic or water-production system there is no residual. If a grower forgets to put in boron, the plants are going to show the deficiency symptoms.”

For more: Brian Whipker, North Carolina State
University, Department of Horticultural Science; brian_whipker@ncsu.edu.

A team effort

North Carolina State University team members on the “Strawberry Diagnostics: a Problem Solving Tool” project include:
Hannah Burrack, Department of Entomology
Frank Louws and Barbara Shew, Department of Plant Pathology
Rocco Schiavone, Jeremy Pattison and Brian Whipker, Department of Horticultural Science
Rob Ladd (developer) and Rhonda Conlon, Extension Information Technology

David Kuack is a freelance technical writer in Fort Worth, Texas; dkuack@gmail.com.

Greenhouse research shifting focus to food crops

To meet the interest and needs of students and a changing
greenhouse industry, the horticulture department at the University of Arkansas is
shifting its focus to the controlled environment production of new and
underused food crops.

By David Kuack

An increasing number of students majoring in horticulture
at the University of Arkansas are focused on food crop production. Horticulture
professor Mike Evans said there has been a shift in interest by the students
from greenhouse-grown floriculture crops to greenhouse-grown food crops. Evans
said that except for turf management, students interested in food crop
production make up the majority of students majoring in horticulture at the
university.

“More and more students who are interested in greenhouse
production want to learn about growing food crops. To accommodate this
interest, we are starting a new class in which we are teaching about the
production of tomatoes, cucumbers, greens and other food crops. We are putting
in different kinds of production systems including hydroponics. The students
will have a really well outfitted lab where they can go in and they will be
raising various food crops with different systems. It will be hands-on.”

Evans said the growing interest in greenhouse food crops
has rejuvenated him and his program.

University of Arkansas horticulture professor
Mike Evans (right) is working with other professors
to develop a program on greenhouse food production
for both students and commercial growers. 

“As the ornamental side of the greenhouse industry has
been undergoing consolidation with fewer but larger operations, we have seen an
increased interest from the industry in growing greenhouse food crops,” he said.
“The number of emails and phone calls related to greenhouse food crops have
greatly increased.

“There are a lot of people growing tomatoes, peppers and
cucumbers in greenhouses. So I started looking at greenhouse food production
and found the area of herbs and greens in many respects has been neglected.
There are people out there doing these crops, but if you look for referenced
research or talk to people, there is a lot less solid research on greens and
herbs.”

Evans has started working with fellow university
horticulture assistant professor and breeder Ainong Shi.

“We are interested in looking at new species of fresh greens
and the breeding of greens,” Evans said. “We are particularly interested in
developing crops that can take Southern hot climates. By converting our
facilities to focus on greenhouse food crops we are looking to become a central
institution to study new species of greens, developing new crops, breeding new
cultivars, and developing production protocols for these crops.”

Developing greenhouse
food crops

Evans said the agriculture industry in the United States
has been largely field-based, but there are signs that changes are occurring
when it comes to controlled environment food production.

“Much of Europe and many parts of Canada and Japan are
significantly ahead of the U.S. when it comes to the development of controlled
environment food production systems,” he said. “We are very much in a catch-up
mode.”

One of the crops that Evans will be looking at regarding
new species is fresh greens.

“Most of the greens research, including breeding, being
done in this country, by-and-large, is for field production,” he said. “Those
same varieties that were originally evaluated in the field are then taken and
grown in the greenhouse. We typically have not bred varieties for greenhouse
production.

“We want to find greens that have lower inputs, that
don’t need much water or fertilizer. They also shouldn’t have many pest
problems, have a rapid production cycle and can especially take heat.”

Evans said the issue with heat is a major obstacle for
greens grown in the southern United States.

“The problem that growers in the southern half of the
U.S. run into during the summer is what kind of greens can they produce? Greens
in the South are more of an early spring and late fall crop. The question is
can we develop greens that can be grown in the heat of summer?”

Mike Evans said he is looking for fresh greens that have lower
inputs, including water and fertilizer, few pest problems, a rapid
production cycle and can do well in hot temperatures.


One of the crops that University of Arkansas researchers
are working on is to develop a heat-resistant spinach.

“We had a breeder here, Teddy Morelock, who did a lot of
spinach breeding,” Evans said. “He passed away, but left us with hundreds
of spinach lines. We’re trying to figure out what we’ve got. Teddy never conducted
greenhouse trials or evaluated the germplasm for production in greenhouses. All
of his evaluations were done in the field. We might be sitting on the best
spinach variety to grow in a greenhouse.”

Another crop that Evans is excited about studying is
dandelion (Taraxacum officinale).

“Dandelion has a higher nutritional value than spinach,”
he said. “It is loaded with iron, vitamins A and C and beta-carotene. It was
considered a medicinal plant. The early immigrants to America brought
dandelions with them for food. A lot of people suffered vitamin deficiencies
and developed scurvy. So they brought the dandelions with them.”

Evans said dandelions can be grown quickly, don’t need a
lot of inputs and are very heat tolerant.

“They are short day plants so they might need some night
interruption lighting,” he said. “That’s not real a concern because the plants
would probably be harvested before they flower.

“There is a great deal of genetic diversity in dandelions
because they are spread worldwide and are segregated. There are a lot of flavors and
traits. We are going to be collecting germplasm from all over the world. We are
going to be breeding dandelions so that they develop into what we want them to
be.”

Setting up a strawberry
cam

As part of the National Strawberry Sustainability Initiative, Evans will be working with professor
Elena Garcia, who is the university’s fruit specialist. The research they will
be doing is part of a program funded by the Walmart Foundation, which is being
administered by the university’s Center for Agricultural and Rural
Sustainability.

“We want to demonstrate and teach growers about various
types of hydroponic systems for strawberry production,” Evans said. “Those
systems might include NFT troughs, gutters, Dutch buckets, etc. There are
various types of hydroponic systems that we feel bring some significant
advantages to the production of strawberries and help to promote a number of
sustainability goals in the program’s guidelines.”

Evans said the type of structures used to grow the
strawberries will also be discussed.

“If a grower considers using high tunnels, he can extend
the season,” Evans said. “Or a grower might consider using drop wall
greenhouses. There is the possibility of providing heat, which could result in
year-round production. There are a lot of possible benefits for our growers.”

Evans and Garcia have been traveling around the state and
meeting with growers talking to them about the different production systems and
explaining how they can be used for strawberry production. Evans said many of
the growers that he and Garcia have met with didn’t know about the differences
in the production systems and didn’t understand the differences.

University of Arkansas professors Mike Evans and Elena Garcia
will be teaching growers in their state about various types
of hydroponic systems for strawberry production.

Evans has renovated two of the university greenhouses in which various strawberry production
systems will be installed and used to produce crops. About 4,000 square feet
has been converted to hydroponic food production with about 1,600 square feet
devoted to strawberries and the remaining used for greens.

“Our
goal is to put in several different systems and to shoot video of what we are
doing from the beginning to end,” he said. “We will shoot video of the assembly
of the different systems as well as the production of the strawberries in each
system. We will film and document in detail everything we do. The videos will
walk the growers through all aspects of design, build, manage, maintain and
grow the strawberries using a specific system.”

Evans said the videos will be used as an educational tool
allowing growers to look at the different production systems and to see the
advantages and disadvantages of each system.
Evans has also been working with University of Arizona
horticulture professor Chieri Kubota and research specialist Mark Kroggel to
prepare videos on the strawberry production research they have been conducting
at the university’s Controlled Environment Agriculture Center.

“Not every system is perfect for everyone,” Evans said.
“Everyone has to look at what they are growing or planning to grow and what is
their market. We want to use the videos as a way to demonstrate these systems
to teach growers how to effectively select one and how to effectively use it.”

For more: Mike
Evans, University of Arkansas, Department of Horticulture; (479) 575-3179; mrevans@uark.edu.

David Kuack is a freelance technical writer in Fort
Worth, Texas; dkuack@gmail.com.

Visit our corporate website at https://hortamericas.com

University of Arkansas scientists tour Belgian strawberry research facility

University of Arkansas researchers gear up to look at
better ways to grow strawberries in controlled environment production
facilities.

Tom Van Delm, coordinator of strawberry research at
Research Centre Hoogstraten (Proefcentrum Hoogstraten) in Belgium, hosted a
tour for University of Arkansas horticulture researchers. The Research Centre
conducts studies on strawberries, tomatoes and peppers. Gerson Van’t Wout, import/export
manager at Hort Americas, joined the tour and filed this report.
Tom
Van Delm (left), coordinator of strawberry
research at Research Centre
Hoogstraten, talks
with University of Arkansas horticulture professor
Mike
Evans about the strawberry research being
done at the Belgian facility.

Strawberry specifics
The University of Arkansas researchers were at the Research
Centre to look at the various aspects of strawberry production being studied.
Although many of the systems being used to produce strawberries, including the
use of gutters, drip irrigation, fertigation and supplemental lighting are
similar to what American greenhouse vegetable growers are currently using,
Van’t Wout said that there are differences in how the crops are grown. He said
there will be a learning curve for U.S. growers who want to add
greenhouse-grown strawberries to their product mix.

Numerous
strawberry production systems,
including NFT troughs, are being studied at
Research
Centre Hoogstraten in Belgium.

Belgian strawberry growers who have switched to greenhouse
production have had an easier time controlling environmental factors including
temperature, humidity and light levels. They also are better able to manage
irrigation, pests and diseases. Van’t Wout said most of the Belgian growers who
have not made the switch to greenhouse production are the ones who have been
doing field production for a long time and are comfortable with that method.

Breeding, pest
management, lighting research

Van’t Wout said that Belgian strawberry breeders are not
hybridizing strawberries specifically for greenhouse production. When a new
variety is introduced by the breeders, he said researchers and growers will try
to produce it in various controlled environment and outdoor growing situations.
Van’t Wout said U.S. greenhouse growers should be able to adapt Belgian-bred strawberries
to their production systems.

The biggest pest problems facing Belgian strawberry
growers are thrips and spider mites. Several trials are being conducted at the
Research Centre with natural enemies, including predatory mites, to determine
their effectiveness on controlling these pests.

Research has also been done with replacing incandescent
light bulbs with LEDs, including Philips GreenPower LED flowering lamp. Van
Delm said that strawberry trials have shown that deep red/white/far red LEDs
are “an effective and energy-efficient replacement” for incandescent bulbs.

Strawberry
research at Research Centre Hoogstraten
in Belgium has included the use of LEDs
to replace
incandescent bulbs for greenhouse production.
For more:
Gerson Van’t Wout, Hort Americas LLC, infohortamericas@gmail.com; https://hortamericas.com.
National Strawberry Sustainability Initiative, http://strawberry.uark.edu. Research
Centre Hoogstraten (Proefcentrum Hoogstraten), http://www.proefcentrum.be/en.

Visit our corporate website at https://hortamericas.com