Vegetarian Newsletter 4
Vegetarian 99-09
September 1999
Save Fertilizer and Improve Water Quality by Using Plant Sap Test Meters
1,800 Acres of vegetables are being produced in central Florida with the
aid of plant sap test metersÖ
 They cost about $350
for each nitrogen and potassium plant sap test kit. Growers can measure
nitrogen and potassium concentrations in their vegetable plants in about
ten minutes right in the field and know exactly whether they
need to apply the next sidedress application of fertilizer to their cropsÖor
not. Average savings of one sidedress application per season are being reported
a savings of about $30 per acre or $54,000 per year for the farms
using plant sap meters in Central Florida. Several growers who used the
meters on a weekly basis to grow sweet corn and watermelons reported exceptionally
high crop yields, in addition to the fertilizer savings.
The environment wins
too 72,000 pounds of nitrogen and potassium fertilizer were not applied
because growers knew the exact amount of these nutrients in their crops
and that they didnít need more. That means a lot less chance of excess fertilizer
leaching into the ground water during irrigation cycles or rainfall. It
takes a lot of energy to produce fertilizer energy savings means less
imported oil and more independence for American farmers and consumers.
Over-fertilization can
cause a lot of problems for your plants and the fruits you harvest from
them. It can reduce vegetable crop yields by increasing salt concentrations
around the root zone and stressing the plant. Postharvest quality of vegetables
can be hurt too. Here are just a few examples:
1. Excessive nitrogen increases graywall
and blotchy ripening in tomato.
2. Excessive potassium reduces fruit
size and firmness in strawberries.
3. Excessive nitrogen enhances leaf
and tip burn in lettuce.
4. High nitrogen increases soft rot
in potato storage.
Extension agents and
crop advisors can improve field diagnosis of plant problems by knowing the
nitrogen and potassium content of the plant. Nitrogen is the mineral element
used most by plants and it is the most readily leached from soils. Potassium
is the next most used mineral element in plants and has important roles
in water potential, photosynthesis, and respiration. When growers are convinced
that these elements are in adequate supply they can more readily focus on
the remaining scenarios with confidence that they are being steered in the
right direction.
Agents doing work with
vegetables who would like to be part of the Nutrient and Water Management
Action Team, a subgroup of FL107 SMP, please contact Richard Tyson (407-665-5554)
or Dr. Marion White (407-330-6735).
(Tyson, Multi-county Agent, Vegetarian 99-09)
More on PLU Numbers 
In the June Vegetarian
(99-06), some PLU (product look-up) numbers were given which apply to some
greenhouse vegetables. The list given was incomplete and could be misleading
to some in the industry. For example, by looking at the listed vine ripe
number (4805), a person might assume there is only one number assigned to
vine ripe tomatoes. In reality, the code listed is assigned to small vine
ripe tomatoes. There is also a PLU code for large vine ripe tomatoes.
The Produce Electronic
Identification Board (PEIB) administers the generic numbering system for
UPC and PLU codes for the produce industry. A complete list may be obtained
by purchasing the PEIBís most recent edition of "A Guide to Coding Fresh
Produce" from Produce Marketing Association, P. O. Box 6036, Newark, DE
19714-6036 or call 302-738-7100.
Thanks goes to Eboni
Wall, Division Assistant, with Produce Marketing Association (PMA) for this
additional information. Before you have PLU labels printed, double check
to make sure you have the correct number for the product!
(White, Vegetarian 99-09)
Evaluations of Sweet Corn Variety Trial
Florida is the nationís
leader in the production of fresh market sweet corn. In 1997-98, there were
14,225,000 crates (42 lb) produced on 41,300 acres for a value of $106,825,000.
A supersweet sweet corn
variety trial was conducted at Long and Scott Farms, Lake Jem, FL, in the
spring of 1999 growing season. The trial was limited to cultivars/breeding
lines of the gene type homozygous shrunken-2 (sh2), i.e., supersweet.
Yellow, white, and bicolor entries were requested from seed companies and
were included in the trial.
Seeds were planted into
an Immokalee fine sand with hand jabbers on March 11. Plots were single-row,
2.5 ft wide x 25 ft long with 9-inch in-row spacing. Four replications were
arranged in a randomized complete block design.
Cultural practices,
provided by the cooperating grower, were comparable to the routine practices
used by commercial growers to produce sweet corn in central Florida.
One row per variety
was harvested by hand at maturity, beginning May 26 and ending May 28. Only
marketable first ears and/or marketable second ears were harvested. Individual
plots were harvested only once. Ears were counted and weighed; sub-samples
of 10 marketable ears per plot were randomly selected, husked, and evaluated
for length, width, maturity, tip fill, husk cover, and kernel color (Table
1 - If you need this table, contact Susie Futch, zsf@ufl.edu,
and it will be emailed to you.)
Sweet corn yields, expressed
as 42-lb crates/acre, ranged from 200 to 299 crates/acre. The highest yielding
entry in the trial was Novartisí GSS 0966-VP at 299 crates/acre. Ear length
ranged from 6.8 inches (Florida XP-7 and R100MVP VAIL-VP) to 7.7 inches
(Billy R and Prime PLS-VP). Ear diameter had some variability. Three lines
were 1.8 inches and three lines were significantly smaller at 1.7 inches.
Husk cover was variable,
with the majority being acceptable to excellent. The most consistent excellent-length
husk cover was exhibited by GSS 0966-VP and by Florida XP-7.
Flags were variable,
with most of them medium to long (>3 inches). Tip fill was uniformly excellent.
The overall best line evaluated in this test was GSS 9866-VP from Novartis.
In a similar test last
year, Florida XP-7 had a similar yield, but several lines were significantly
higher. Bandit, Ice Queen, Morning Star, and three numbered lines were the
top performers on sandy soil. Seed company interest in sweet corn evaluation
on sandy soils in central Florida is not sufficient to support the test
as evidenced by the lack of company participation in 1999. Future direction
for this program is open and support is solicited.
(White, Vegetarian 08-99)
Offseason (Summer) Management of Vegetable Land
A drive-by survey of
over-summering practices for managing vegetable land was conducted in Palm
Beach and Martin Counties from late June to mid-July, 1999. Approximately
8,000 acres (85+% of the cultivated acreage) was surveyed. There were a
total of 78 different farm locations managed by 19 different growers (16
locations were not surveyed). Full-bed plastic mulch culture was practiced
on 60 different farm locations by 14 different growers (approximately 6,625
acres devoted to pepper, tomato, eggplant, squash, cucumbers, etc.). Open
bed culture was practiced on 18 farm locations by six different growers
(approximately 1,375 acres devoted to Chinese vegetables, herbs, sweet corn,
and gladioli). Acreages for over-summer practices and culture methods are
shown in the following table.
|
Over-Summer Practice
|
Full-bed Plastic
Mulch Culture (ac)
|
Open-bed Culture
(ac)
|
| Disk |
62.5% (4,120)
|
53.4% (740)
|
| Cover crop z |
22.4% (1,480)
|
44.7% (615)
|
| Over-summer old spring plastic for fall
second crop |
9.4 % (620)
|
|
| Flooded |
2.7% (180)
|
|
| Weeds |
2.1% (140)
|
|
| Mowed |
0.6% (40)
|
|
| Summer crop production |
0.2% (15)
|
1.5% (20)
|
| Total |
100% (6,595)
|
100% (1,375)
|
| z The cover crop used most frequently was
a sorghum/sudangrass hybrid; there were very small acreages of sesbania. |
(Shuler, Extension Agent IV, Palm Beach County, Vegetarian 99-09)
Sweet Onion Variety Trial, Spring 1999
Sweet (short-day) onions
are a relatively minor crop in Florida. Production exists as both dry bulbs
(mature) and green tops (immature). Limited production exists throughout
the state. One of the biggest deterrents for increased production is competition
from established markets from the south Texas and south Georgia areas. However,
the potential exists for expanded production, especially in the areas of
local sales and direct marketing.
The objective of this
trial was to evaluate the performance of sweet onion varieties under north
Florida conditions.
The transplants for
this trial were produced from field beds at the NFREC, Quincy. Twenty four
entries were seeded on 7 Oct 1998. Seed were planted at rate of about 30
seed per ft into rows spaced 12 inches apart. Preplant fertilization of
seedbeds was 30-40-40lbs/a of N-P2O5-K2O.
Dacthal 75 W at 9 lbs ai/a was applied over the top after seeding. Seedbeds
were top-dressed once with 34 lbs N/a. Entries were transplanted into the
production field on 15 Dec 1999. Soil type was an Orangeburg loamy fine
sand. Preplant fertilization was 60-80-80 lbs/a of N-P2O5-K2O.
Production scheme was 3 rows spaced 15 inches apart under a 5 ft tractor
and in-row spacing was 5 inches (62,726 plants/a). Goal 2XL at 0.5 lbs ai/a
was applied on
Soil surface before
transplanting and Dacthal 75 W at 9 lbs ai/a was applied over the top after
transplanting. Nitrogen was applied twice during the season at 50 lbs N/a
each time. One top dressing of K2O as KCl at 60 lbs/a was made
during the season. Registered pesticides were applied as needed to control
pests.
Entries were harvested
as they matured, where mature was defined as when about 25% of the tops
of an entry had fallen down naturally. Bulbs were lifted, allowed to dry
for a few hours, and tops and roots removed. Bulbs were then placed in bushel
baskets and dried for 72 hours at 100o F in large drying rooms.
After drying time was complete, onions were removed, allowed to cool down
and graded. Grading consisted of discarding culls (small onions, splits,
off color and decayed) and sizing into medium (1.5-2 inches), large (2-3
inches) and jumbo (>3 inches) categories. Bulbs were then weighed and counted.
Harvest occurred from
the period of 21 April to 13 May. Total yields ranged from 1145 50 lb bags/a
for ëSSC 6361í to 209 50 lb bags/a for ëLinda Vistaí. No other entry produced
yields as high as ëSSC 6361í. Yields were excellent in 1999 except for the
late entries due to several rain storms near harvest time. ëSSC 6361í produced
the largest bulb at 16.5 oz and ëDPS 1041í produced the smallest at 8.4
oz. Percent marketable bulbs ranged from a low of 30.0% for ëLinda Vistaí
to a high of 96.7% for ëRCS 1919. Percent bolting level was very low (<1%)
on all entries.
Table 1. Onion variety trial, Spring - 1999. NFREC, Quincy.
|
Entry
|
Source
|
Days from transplanting
|
Yield
(50 lb sacks/a)
|
Avg bulb wt (oz)
|
Percent
marketable
|
| SSC 6361 |
Shamrock
|
140
|
1145 a z
|
16.5 a
|
90.2 a-c
|
| Sweet Success |
Sunseeds
|
146
|
856 b
|
15.6 ab
|
87.7 a-c
|
| Equanex |
Petoseed
|
146
|
727 bc
|
14.5 a-e
|
80.4 a-e
|
| Rio Bravo |
Rio Colorado
|
146
|
719 bc
|
14.6 a-d
|
79.3 b-e
|
| PX 7092 |
Petoseed
|
146
|
718 bc
|
12.8 c-g
|
84.4 a-e
|
| Sweet Magnolia |
D. Palmer
|
149
|
702 b-d
|
16.4 a
|
68.1 e-g
|
| Savannah Sweet |
Petoseed
|
146
|
670 cd
|
14.6 a-d
|
82.9 a-e
|
| Sugar Queen |
Shamrock
|
127
|
646 cd
|
10.7 g-j
|
84.1 a-e
|
| Mr. Max |
Rio Colorado
|
146
|
621 c-e
|
14.2 a-e
|
71.0 d-f
|
| RCS 1919 |
Rio Colorado
|
127
|
584 c-e
|
10.0 h-k
|
96.7 a
|
| RCS 1027 |
Rio Colorado
|
146
|
583 c-e
|
13.1 c-f
|
86.3 a-d
|
| Timon |
D. Palmer
|
129
|
570 c-e
|
8.5 jk
|
95.2 ab
|
| Big Pete |
D. Palmer
|
129
|
547 de
|
9.9 i-k
|
94.6 a-c
|
| Chula Vista |
Petoseed
|
146
|
475 ef
|
10.6 g-j
|
84.9 a-d
|
| Granex 33 |
Asgrow
|
149
|
466 ef
|
15.1 a-c
|
58.5 f-i
|
| DPS 1041 |
D. Palmer
|
129
|
456 ef
|
8.4 k
|
92.6 a-c
|
| Yellow Granex |
Sunseeds
|
149
|
378 fg
|
12.2 e-h
|
61.9 f-h
|
| Evita |
Shamrock
|
149
|
346 f-h
|
13.3 b-f
|
44.6 i-l
|
| SXO 1503 |
Sunseeds
|
149
|
336 f-h
|
12.6 d-g
|
55.4 g-j
|
| Daybreak |
Shamrock
|
149
|
330 f-h
|
11.3 f-i
|
78.1 c-e
|
| Pegasus |
Asgrow
|
149
|
286 gh
|
13.3 c-f
|
40.6 j-l
|
| Dessex |
Sunseeds
|
149
|
243 gh
|
13.6 b-f
|
47.3 h-k
|
| Sunsweet |
Sunseeds
|
149
|
209 h
|
12.1 e-h
|
35.9 kl
|
| Linda Vista |
Petoseed
|
149
|
209 h
|
12.8 c-g
|
30.0 l
|
| z Mean separation Duncanís
Multiple Range Test, 5% level. |
(Olson, Vegetarian 99-09)
Planting Depth as a Growth Stimulant
In March and July articles
we discussed vegetable crop growth stimulation by means of biostimulants
(chemicals) and biologicals (organisms), respectively. While both of these
methods boast documented successes, the benefits of use may not always out
weigh the cost of application. Florida growers, who establish their crops
from transplants, have long enjoyed an environmental manipulation used to
increase plant growth and yield. That environmental manipulation is simply
Ö plant it deeper!
In the early 1990s the
standard planting depth for tomato and pepper transplants in Florida was
to a level between the cotyledons and the root ball. However, several years
of research at the University of Florida showed a positive linear increase
in plant growth and yield occurs with incremental increases in planting
depth (Fig. 1).
The phenomenon appears
to occur across cultivars, seasons, geographic areas, irrigation methods,
and cultural practices in Florida in general (Vavrina et al., HortScience,
1994, 1996). Further unpublished work has shown the technique to be effective
with watermelons, but without the yield enhancement. But, additional vine
cover and faster development have associated economic benefits as well.
It seems apparent that
planting transplants deeper also works well in other areas of the United
States. Hanna et al. (HortScience, 1997) have confirmed similar findings
for fresh market tomatoes in Louisiana. Bennett (Ohio State) and Murray
(University of California) have seen increased growth and some yield enhancement
in processing tomatoes (personal communication). Benefits derived from this
environmental manipulation extend beyond growth and yield as research from
Massachusetts (Mangan et al., Proc. Stand Estab. Conf., 1996) showed that
deeper planting of processing cherry pepper reduced plant lodging and Miller
et al. (JASHS, 1969) found more uniformity in cabbage head size with deeper
planting in Virginia.
Unfortunately, while
passing attempts to explain this phenomenon have been made, no studies have
documented the mechanism(s) involved. But in the mean time you can put this
cost-effective technology to work for you, just plant it deeper!
Plug Transplants for Strawberry Crop Establishment in Florida
Strawberries in Florida
are typically planted using bare root transplants. These bare root plants
are typically established by applications of overhead irrigation from 7
to 10 days for up to 8 hours a day. (Irrigation periods will vary depending
on weather conditions and plant health.) This irrigation represents approximately
a of the total water usage for the entire strawberry season. In addition
to the heavy water usage associated with establishing bare root transplants,
other difficulties exist. These difficulties include relatively high plant
mortality rates and problems often related to overhead irrigation such as
nutrient leaching, increased weed pressures, and disease dissemination.
The use of plug transplants
for strawberry establishment has the potential for addressing many of the
problems associated with the use of bare root transplants. Research conducted
the past two years at the University of Florida, GCREC, Dover Strawberry
Lab has indicated several advantages of using plugs. First, plugs can be
established using only drip irrigation, eliminating the need for overhead
irrigation and dramatically decreasing water usage. For example, in the
1998-99 season at Dover, approximately 800 gallons of water per acre were
applied through drip irrigation the first two weeks to establish the plug
plants. For contrast, approximately 600,000 gallons of water per acre are
typically used by growers in this same time period using overhead irrigation.
Second, plant health defined by characteristics such as root dry weight
and leaf number was significantly better for plugs than for bare root plants.
This improved plant health apparently led to the third advantage of using
plugs, greater early yield. In the 1998-99 season, early yields (totals
from November and December) with plug transplants were 140 flats per acre
higher than yields from bare root transplants. Prices received for strawberries
during these months are about three times higher than prices received later
in the season.
Unless (or until?) water
restrictions force growers to use plugs for transplanting strawberries,
the primary motivation for using the plugs will naturally be economics.
Plugs currently cost nearly twice as much as bare root plants. This is a
tremendous cost to incur unless the grower is convinced the up front investment
has a good chance of increasing overall profits. However, the economic incentive
may already be great enough. Primarily, the increase in early yield can
generate economic advantage. Other economic advantages of using plugs may
include: possible reductions in disease or weed pressures by not using overhead
irrigation for crop establishment and labor reduction by not having to replant
as many transplants due to lower mortality rates.
The use of plugs for
crop establishment of strawberries has potential to be a tremendous tool
for increasing profitability as well as conserving water resources. In the
coming season, a demonstration project will be conducted on five farms in
Hillsborough County. Each farm will have one-quarter acre of plug transplants
and one-quarter acre of bare root transplants which will be directly compared
for yield, disease and weed pressures, water use, and certain plant characteristics.
In addition, John Duval (our new horticulturist at the Dover Lab) will be
evaluating the effects of planting dates on yield and other parameters using
both plugs and bare root plants. Economic evaluations will be made using
data from both of these projects as well as the data from the first two
years of this plug project. These projects will allow us to more accurately
evaluate the potential of using plugs for strawberry establishment and to
estimate how they might best be used in commercial production. This information
can then be used by growers to evaluate how plugs can best be used by them
to maximize their farmís profitability and sustainability.
(Waldo, Multi-county Agent, Hillsborough County, Vegetarian 99-09)
Horticulture Events
at 1999 4-H Congress
Our 4-H horticulture
committee composed of Bob Black, Jeff Williamson, and myself conducted three
plant science events for the 4-Híers at Gainesville during State Congress,
the week of July 26-30, 1999. The following are the results.
1. Horticulture Leadership Track. We provided two days
of classes on various topics related to horticulture. Some of the class
topics covered such things as: writing a garden record book; lawn mower
safety; plant bonsai; insect eating plants; container culture; lake watch;
and butterfly gardening. Over 40 4-H members attended. State 4-H specialist
Joy Jordan assisted us with this event. Instructors were agents, Ray Zerba,
Linda Landrum, Charlie Fedunak, and Bob Renner, along with the specialists.
2. Plant Demonstrations. Both team and individual demonstrations
were heard and judged by Heather Miller, Mark Gal, and Jackie Host.
| Plant Demonstration Results: |
| Placing |
Name
|
County
|
Subject
|
| 1st |
Pebbles Fullford |
Marion |
Hydroponics |
| 2nd |
Jackie Lundy |
Glades |
Sugar bill |
| 3rd |
Kyle Smith |
Osceola |
Propagation |
| 4th |
Travis Nettles |
Suwannee |
Cold frames |
| 5th |
Crystal Baker and Tariea Cox |
Marion |
Reproduction |
Awards trip: Pebbles Fullford was selected to represent Florida 4-H at the
national competition at the NJHA convention, Tampa, Nov. 5-6, 1999.
3. Horticultural Identification and Judging Results.
| Placing |
Score
|
Name
|
County
|
| 1 |
778
|
Pebbles Fullford
|
Marion
|
| 2 |
732
|
Breanna Mock
|
Duval
|
| 3 |
697
|
Amy Oldberg
|
Marion
|
| 4 |
675
|
Katie George
|
Marion
|
| 5 |
641
|
Holly Batten
|
Marion
|
| 6 |
630
|
Alicia Kamholtz
|
Marion
|
| 7 |
499
|
Lynn Moss
|
Hendry
|
| 8 |
415
|
Sara Puletti
|
Hendry
|
| 9 |
379
|
Roy Dutcher
|
Hendry
|
| 10 |
367
|
Carrie Lorick
|
Marion
|
| 11 |
362
|
Katie Robbins
|
Marion
|
| 12 |
338
|
Dustin Taylor
|
Marion
|
| 13 |
327
|
Jess Maxwell
|
Volusia
|
| 14 |
310
|
Lauren Mock
|
Duval
|
| 15 |
301
|
Wendy Kirkland
|
Hendry
|
| 16 |
298
|
Ben Colbert
|
Hendry
|
| 17 |
294
|
Chris Mattson
|
Volusia
|
| 18 |
291
|
Andy Massey
|
Hendry
|
| 19 |
268
|
Chrisy Laughter
|
Volusia
|
| 20 |
217
|
Abby Landrum
|
Volusia
|
The Marion County team was selected to compete at NJHA convention in November.
Hendry County placed second, followed by Volusia at third place.
(Stephens, Vegetarian 99-09)
|
