AGRICULTURAL RESEARCH CENTER
IFAS, University of Florida
Rt. 2, Box 157
Dover, Florida 33527
i- T n <\ 0 \
Dover ARC Research'Report DOV-1982-3 December 1982
EFFECT OF STRESS ON STRAWBERRY TRANSPLANT GROWTH ND FRUITING RESPONSE .Pf
E. E. Albregts and C. ii. Howard
Since most strawber y transplants set in the fruiting field in Florida are not
dormant, they are m re subject to stress (1,2). Transplants are removed from
the soil in the nurs ry, placed in small bundles, and handled in various ways
until set in the fruiting field. Some transplants are set in the fruiting
field immediately af er removal from soil, while others are placed in coolers
for an indefinite pe iod before transplanting. Occasionally, growers will
bury the plant roots in the nursery soil for periods ranging from one to five
hours. Some plants re occasionally left on the soil surface, either in the
nursery or fruiting field, for lengthy periods. Transplants are also placed
under stress between time of running the blade under the plants in nursery
until irrigation is tarted on transplants after setting in the fruiting
field. Because the weather is very warm during plant harvest, excessive
wilting of plants ca occur with some harvesting, storing, and setting
procedures. If defo nation of non-dormant plants occurs, plant growth,
development, and fru ting may be delayed (2).
An experiment was co ducted to evaluate some forms of stress resulting from
handling procedures o determine their effects on foliage loss, plant size,
plant loss, and Janu ry and total marketable yields. 'Dover' and 'Florida
Belle' strawberries ere grown for three seasons in winter fruiting trials
using the annual hil culture system. Strawberry plants were dug in October
of each season from C-Dover nurseries, placed in bundles of 25 plants and
wrapped in black poly thylene, and subjected to the following treatments:
1) immediately rinsed and placed in a cooler (40F) overnight, treatment
labeled as the control ; 2) left on the soil surface in direct sunlight for
2.5 hours and then pl ced in cooler overnight; 3) same as treatment 2 but
left in the sun for 5 hours; 4) same as treatment 2 but with roots buried in
dry soil, 5) same as treatment 2 but with roots buried in wet soil; 6) dug on
planting date, rinsed and set immediately in fruiting field with all other
treatments. Temperat re highs during the plant harvest period averaged 84F.
After setting, overhe d sprinkler irrigation was used to establish the
transplants for a period of 14 days. Plants were visually rated for foliage
loss, plant size, and plant mortality after establishment. Fruit were harvested
1Professor (Soils) an Professor (Plant Pathologist), respectively, with the
University of Florida, IFAS, Agricultural Research Center, Rt. 2, Box 157,
Dover, Florida 33527.
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twice weekly, gra ed, and weighed from January through April of each season.
Preplant treatment s affected foliage loss, plant size, and plant mortality of
both cultivars (T ble 1). Plants in treatment 2, 3, and 4 were adversely
affected by expos re to the sun and heat and wilted excessively, especially
those in treatment 3. Plants with roots buried in moist soil had less foliage
loss, lower mortality, and were larger after the establishment period than
plants with roots uried in the dry soil. January marketable yields were
generally reduced hen foliage loss and plant mortality were high. Growers
know that early yi lds are important because fruit prices generally decrease
as the season prog esses. Total marketable yields were also often reduced
when foliage loss md plant mortality were high (Table 2).
The following is a list of generalizations drawn from this and other research
and on observation on the effect of transplant stress on fruiting response.
1. To reduce foli ge loss on the plant from stress during the period from
plant harvest o transplanting follow these steps:
(a) Irrigate the nursery before digging transplants and keep the soil
moist du ing the plant harvest period.
(b) If plants are left in nursery after harvest, bury roots in the
moist soi .
(c) Remove pl nts from the nursery within an hour and moisten them before
short ter storage.
(d) Keep plan s from wilting while in temporary storage.
(e) Set plant immediately upon removal from storage and start overhead
irrigation immediately.
(f) Plants se immediately after harvest have the least amount of stress
and are e tablished easier than plants treated in any other manner.
In additi n, early and total yield will be maximized.
(g) The long transplants are held in storage the more difficult the
transplants are to establish. More irrigation will be required to
establish hem and greater foliage loss is likely.
2. The non-dormant trawberry transplant should retain at least 3 healthy
leaves through t e end of the establishment period.
3. These leaves act as a food source for the plant during and perhaps for a
time after the e tablishment period. Since the root system must re-develop
after transplant ng, only a limited amount of fertilizer uptake occurs
during establish ent. Thus plants do not have the capacity to produce
the sugars needed for the rapid production of the new root system and
foliage.
4. If all or most o the foliage is lost in non-dormant plants, the limited
food reserves in the crown and roots slow root and foliage development
and often place uch a stress on the plant that it dies before it can
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regenerate en ugh food producing capacity to sustain itself. Dormant
plants have s arch in the upper root system and can use this instead of
food reserves in the foliage as a food source in the production of new
toots and fol age.
5. The length an the severity of the wilting to which an otherwise healthy
transplant is subjected will determine the amount of foliage lost which
will affect p ant growth and plant mortality. If the fall and early
winter temper tures are above normal, growth of partially defoliated
transplants c be greatly enhanced, and the defoliation effect can be
partially over ome. With below normal fall and winter temperatures, the
converse is tr e.
If stress is place on the transplant at any time from the moment the blade
is run under the p ants in the nursery until plants are established in fruit
production field, hen growth, mortality, and fruit yield can be adversely
affected.
Literature Cited
1. Albregts, E. E. and C. M. Howard. 1982. Effect of transplant stress on
strawberry per ormance. HortScience 17:651-652.
2. Albregts, E. E. and C. M1. Howard. 1972. Influence of defoliation at
transplanting o strawberry growth and fruiting response. HortScience 7:
569-570.
Effect pf preplant treatments during 3 seasons on foliage loss,
size, and mort lity of strawberry plants at end of establishment period.
FoLiage loss Plant size
Preplant (%) (% Of control) ilortalityz (%)
treatments 19 8 1979 1978 1979 1980 197G 1979 1980
1. ControlY
2. Plant in
sun 2 1/2
hr
3. Plant in
sun 5 hr
4. Roots in
dry soil
5. Roots in
wet soil
6. Direct set
3. Plant in
sun 5 hr
4. Roots in
dry soil
5. Roots in
wet soil
6. Direct set
16i
101
un
55i
22
12
ZFoliage loss and
was counted.
YPlants were rinse
per treatment 2-5
x lean separation
Test, 5% level.
Dover
4c lOa l00a
100b
1.4b O.Ob 0.Ob
52b 88b 72c 5.7a 1.4b 10.Oa
43a
32b
57c 66c
66b 78b 104b
12c ---
4c 117a
--- 18.6a 10.Oa
2.9ab 2.9b O.Ob
95ab 113ab --- O.Ob O.Ob
102a 122a O.Ob 1.4b 1.4b
Florida Belle
Oc lOOa lOa lOOa O.Ob O.Oc 0.Oc
24ab 66b 90ab 61d
36a
20b
16b
Oc
--- 2b 82b
10.Ua O.Oc 14.3a
--- 8.8a 8.6b
93a 88b 80b 4.3b 4.3b O.Oc
--- 94ab 73c
93a :.98a lOOa
plant size visually
--- O.Oc 1.4c
O.Ob O.Oc 1.4c
rated' from' to 100 and'mortality loss
d and placed at 30C overnight; planted following day as
columns for each cultivar by Duncan's Hultiple Range
Controly
Plant in
2 1/2 hr
Sl
Table 1.
i
Table 2. Effect of preplant treatments during 3 seasons on January and
total market le fruit yields.
Preplant January yields (flats/A) Seasonal yields (flats/A)
treatments 1978 1979 1980 1978 1979 1980
Dover
1. Control 625az 582bc 339a 2309a 2431b 4645a
2. Plant in sun
2 1/2 hr 530b 538bc 52b 2318a 2414b 3412c
3. Plant in sun
5 hr --- 339c 69b --- 1632c 3595c
4. Roots in dry
soil 495b 434c 251a 2457a 2318b 4289ab
5. Roots in wet
soil -- 703b 260a --- 2692b 4159b
6. Direct set 625a 885a 304a 2692a 3265a 4315ab
Florida Belle
1. Control 790a 582a 243ab 277Ua 3013ab 3022ab
2. Plant in sun
2 1/2 hr 469b 530a 69b 2197b 2726ab 2891b
3. Plant in sun
5 hr --- 321b 217ab --- 2440b 3334ab
4. Roots in dry
soil 747a 399b 156ab 2614ab 2640b 3569a
5. Roots in wet
soil --- 425b 217ab --- 2944ab 3306ab
6. Direct set 825a 547a 339a 2744a 3056a 3421a
Zlean separation
Test, 5% level.
in columns for each cultivar by Duncan's Mlultiple Range
HISTORIC NOTE
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not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
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