VegNet Vol. 13,
No. 3.
On the WEB at: http://vegnet.osu.edu
If experiencing problems receiving this
fax, Call 614-292-3857
In This
Issue
1. 18th International Pepper Conference
2. Broadcast Application of Granular Urea for Sidedress
3. Water, Water Everywhere
4. Controlling Plant Height in Vegetable Transplant Production
18th
INTERNATIONAL PEPPER CONFERENCE
It's the place for information and networking for all pepper
producers and researchers.
Why
Attend.
Take advantage of this exciting opportunity
for growers, industry, processors, and scientists to make
new business relationships, meet specialists in the
different fields, and have access to the latest technology,
products and services. You'll leave with an increased knowledge of recent
advances in all areas of our industry If you have an interest in peppers
you cannot afford to miss this conference.
Experience an unsurpassed opportunity for networking and the
multi-disciplinary sharing and exchange of the latest scientific and practical information related to
pepper breeding, production and
processing.
And the venue- the fabulous Renaissance
Esmeralda in
TOPICS
Breeding and Genetics - Germplasm evaluation and utilization, crop physiology and technology
Horticultural Management and Production - Production methods, cultural systems and sustainable approaches
Integrated
Post Harvest Issues - Post harvest physiology and
technology, economics, marketing and trade
Overview of Pepper Production Throughout
The World
Brief summaries of the pepper crop in areas around the
An Update on Biotechnology in Peppers. Reports on Research Funded by
the
Field Tour
This full day tour is an outstanding, hands-on
opportunity to learn more about peppers, the agriculture, and the
area. Get on board and we'll make multiple stops for a close up look
and provide a wealth of information you can take with you. Green and colored pepper fields Open fields Shade house
and Greenhouse-grown peppers. Large pepper variety
trial - includes entries from all the
major seed companies, plus university material. Expanded overview of the
Registration
Regular Registration March 11 to April 20th - $325
Late
Registration and on-site after April 20th - $400
Register
online www internationalpepper.com
Conference Coordinator: Aimee
Broadcast
Application of Granular Urea for Sidedress? by Robert Mullen and Edward Lentz, From: OSU C.O.R.N Newsletter
2006-04 February 21, 2006 - March 8, 2006 provided by Jim Jasinski
Ammonia is the precursor to all other forms of nitrogen (N), and
with the increased cost of natural gas (over 70% of the cost of ammonia
production) in the U.S. compared to other countries around the world, it has
become more difficult for U.S. ammonia manufacturing facilities to compete on
the global market. Over a quarter of the ammonia manufacturing facilities in
the
Surface application of granular urea is typically not the most efficient way to
supply N to a growing crop. It is usually recommended that urea be incorporated
to ensure that N is not lost by volatilization. As urea is broken down by the
enzyme urease it becomes ammonia and seeks out water to form the stable N
form ammonium. When urea is surface applied, there is very little soil surface
area and resultant moisture to react with ammonia and keep it from floating
away as a gas (volatilization). Volatilization loss potential is increased when
urea is surface applied to a no-till soil that has a lot of surface residue,
and loss potential is increased by high soil pH. This is why surface application
of urea is specifically discouraged on no-till production fields and recently
limed fields (specifically no-till fields where lime is not incorporated).
Incorporation is the key to ensure volatilization losses are minimized, and
this does not necessarily mean mechanical incorporation. Rainfall approaching
half an inch can adequately incorporate urea and minimize N loss.
Polymer coated urea products are another potential dry source of N that can be
applied preplant or sidedress.
The semi-permeable polymer coating allows for slow release of N that increases
as soil temperature increases. The limited amount of University research
available shows that for preplant applications this
application method can be an attractive alternative in certain high N loss situations,
but the fertilizer material does cost more than urea. To see the economic value
of these materials usually requires N rates to be lower than rates of standard
urea.
Editors Note: In general, polymer
or sulfur coated materials are not used for vegetables in this part of the
country because of the high demand for nitrogen in a short period of time by
most vegetables grown in OH
Water, Water Everywhere…
by Shari
L. Plimpton, Ph.D., Food Safety Educator - Ohio and
Indiana Specialty Crop Food Safety Initiative
Water suitable for agricultural uses seems to be hard to come by
these days if you read all of the reports out there about water quality for
fresh fruits and vegetables. We emphasize water’s importance for fresh produce
food safety through the GAP (Good Agricultural Practices) program across the
country, yet we (those of us who are trying to be helpful) still seem to be
generating as much confusion as we are solutions. So in this article I hope to
address some of the questions I am hearing with some new information and a
little perspective.
In
January of this year, at the Ohio Fruit and Vegetable Grower’s Congress, we
featured Dr. Trevor Suslow, Extension Research
Specialist from UCDavis to speak on the topic of
Water Quality and Fresh Produce Safety. Those who were able to attend heard him
report on research findings that demonstrated both bacterial survival and increasing
bacterial numbers at refrigerated temperatures for certain strains of
infectious organisms. Clearly, this news underscores the importance of the goal
of preventing microbial contamination, since our best efforts to control
microbial contamination (washing and refrigeration) are not foolproof (although
both are still necessary).
Recommendations
published by Dr. Suslow and other researchers, and
the continued reporting of foodborne illness are
driving large-scale growers to adopt water quality practices that are even more
diligent than those we have recommended in the GAPs
program. Growers with known contamination issues are testing their water
sources for fecal coliform bacteria and E. coli
at least twice a month if from open sources and monthly if from closed wells.
Dr. Suslow is recommending that growers who have not
identified a microbial contamination issue test just as frequently for at least
a year before reducing the frequency to once a year for enclosed wells and at
least 3 times a season (Midwest) for open water sources.
Treatment
of water to be used for agricultural purposes (irrigation, spray) is an
important precaution if you hit the action threshold of 1000 fecal coliform bacteria per 100 ml and/or 126 E. coli bacteria
per 100 ml. Prior to employing your treatment options,
re-test for whatever microorganisms are indicated. If you are testing a well,
inspect and make sure there are no opportunities for surface water to breech
the well. Shocking the well with chlorine should address the problem. Retest. With an open water source, it would be necessary to
add a filtration system to the water pulling from the source and follow that
with an automatic chlorination system, so you can chlorinate the water for
sensitive applications. Again, retest.
Using
potable water is necessary in the packinghouse to avoid introducing a microbial
contamination problem that did not exist coming out of
the field or orchard. Since washing does not eliminate microorganisms, the goal
in the packinghouse is simply to keep the water clean enough not to cause or
increase microbial contamination. Repeatedly, research is showing that the most
reliable method for accomplishing this is a chlorination system that is closely
monitored maintaining free chlorine levels of 150 to 200 ppm.
Monitoring
the free chlorine level and pH of the water on a continuous basis is simply an
essential part of the process. Measuring chlorine alone gives you only half of
the picture: a half that may mislead you regarding the effectiveness of the
sanitation of your water. If the pH is within 6.8 to 7.2, the level of free
chlorine that is in the most effective form (hypochlorous
acid) is at its highest. Most of our water sources tend to run basic, so acetic
acid can be used to bring the pH into range.
And
why am I writing about chlorine so much and not other sanitation methods?
Because, current research is not showing any other methods to be as effective
for the treatment of water under agricultural conditions as is chlorination. If
you are using copper ionization, please know that high levels of organic
material can render it ineffective. Researchers are recommending that you
supplement a copper ionization system with chlorination to improve disinfection
of the water, particularly in packinghouse operations. If you are considering
purchasing a copper ionization system ask the dealer to demonstrate its
effectiveness in agricultural applications. A system should be able to
effectively result in a five-fold reduction of fecal coliform
and particularly E. coli. Ultimately, the goal is to minimize the risk
and recognize the potential impact of the decisions you make regarding how to
manage your water sources.
For more information and links to research articles on this and
related topics visit www.midamservices.org and select
"Projects" from the left navigation. For free Good Agricultural
Practices materials, presentations and food safety consultations contact us on
the web site listed above or call Mid American Ag and Hort
Services at 624-246-8286 or maahs@ofbf.org. You may also subscribe to a free
e-newsletter by going to the web site above and clicking on the "Free
Email Mailing List" button. These services are available for
Controlling
Plant Height in Vegetable Transplant Production
By Bob Precheur. From
several sources, see below
Plant Height is equal to the number of nodes and length of each internode. Both are influenced by greenhouse temperature.
Node number or formation is a function of the average greenhouse temperature,
increasing as the average greenhouse temperature increases. Seedling elongation
is most rapid in the early morning.
Internode length
is influenced by the difference between the day and night temperature referred
to as DIF (Day temp – Night Temp = DIF).
As DIF increases, so does internode length in
most species.
Transplant height can primarily be controlled through increased
night and reduced day temperature or low temperature pulses at or near the
beginning of the day (Negative or Zero DIF). Low temperature pulses can be
applied during first 2 to 4 hours of daylight.
Environmental and cultural factors promoting shoot and root growth
Light intensity: Low light promotes shoot growth while high light
favors root growth.
Moisture: Overwatering or high moisture
favors ‘leggy’ transplants while low moisture promotes root growth
Nutrition: High NH4 & P promotes shoot growth. High NO3 &
Ca promotes root development
Deleterious effects of high nutrient levels: High Nitrogen levels
favor shoot growth and can cause an imbalance (decrease) in root/shoot ratios.
Transplants with higher root/shoot ratios (well developed root
systems) suffer less transplant shock when field set (Masson et al., 1991)
Mechanical Height Control by Brushing
Results: Reduces plant height; Increases stem and petiole strength;
Improves stress tolerance; Enhances stand establishment in the field.
This technique can provide from 20 to >50% height reduction.
Ten to 40 brush strokes per day up to 10 minutes per day.
A Practical Guide to
Using Mechanical Stimulation to Prevent Stretching in Tomato Transplants. From NY State Ag. Exp. Sta.,
Mechanical stimulation is an effective way to make plants grow
tougher and preventing excessive stem elongation (stretching). Brushing is the
simplest way of treating transplants in the greenhouse. Like everything with
plug production, it needs to be done just right to be effective, but it can be
a useful tool.
How to brush: Brush across the top of the
canopy in long gentle strokes. The best tool depends somewhat on the width of
the bench. An unpainted broomstick is good because the leaves don't stick to
it. A piece of 3/4 conduit inside a piece of 2 plastic pipe should work for
larger benches because the plastic pipe can roll to prevent plant damage. Run
the tool about 1/2 to 1 inch below the top of the canopy to lean the plants
over gently.
How much to brush: The amount needed varies with
the season. In spring, 10 times back and forth, once a day, is about right. In
mid-June it takes 20 strokes. More treatment than that can damage the leaves.
If you see damage, it is too much!
With
a long bench, it can take a while to go to one end and back. That seems not to
matter. We had the same effect whether the stokes came
continuously or up to 10 minutes apart. The plants remember, and add up, the
stimulus over a rather long time.
When to start: Begin treating when the plants
are about 2-1/2 inches tall. We have found little benefit is starting earlier,
and the chance of damaging the small plants is greater. Starting later is not
only ineffective, but the leaves are so big that they tear. If the plants have
been treated starting at 3 inches, the leaves are hardened to the treatment and
handle it well even when the plants are larger. The first day or two, a lighter
treatment is a good idea. You will notice that the plants wilt immediately the
first time. They recover quickly and don't wilt when they are used to being
brushed. (Dr. Joyce Latimer in
When to brush: Brush when the foliage is dry
but the plants are not wilted. Mostly, this will be before watering in the
morning. We have found similar effectiveness in the morning and afternoon.
Brushing
also works well for cucumbers. Begin as soon as the cotyledons open, and
brush for the next 5 days. It keeps the hypocotyl
about 25% shorter.
References:
Mechanical conditioning for controlling excessive elongation in
tomato transplants: sensitivity to dose, frequency and timing of brushing. By Lauren
C. Garner and Thomas Björkman
Department of Horticultural Sciences, New York State Agricultural
Experiment Station, Cornell University, Geneva, NY 14456. Journal of the
American Society for Horticultural Science 121: 894-900
Dose and timing of brushing to control excessive hypocotyl elongation in cucumber transplants
Thomas Björkman. Department of
Horticultural Sciences, New York State Agricultural Experiment Station, Cornell
University, Geneva, NY 14456. HortTechnology 9:40-42.
1999.