Carbohydrate Injections as a Potential Option to Improve Growth and Vitality of Live Oaks

Abstract

This study evaluates the effects of carbohydrate injections on the growth and vitality of live oak (Quercus virginiana P. Miller). Glucose, sucrose, or a 50:50 mixture of both carbohydrates at increasing concentrations [0, 40, 80, and 120 g/L (0, 5.3. 10.6, and 16.0 oz/gal)] were injected into live oaks. Trunk and root growth, net photosynthesis, root and twig carbohydrate concentration, and chlorophyll fluorescence were monitored. Isotope composition of twig and root samples was measured as an indicator of injected carbohydrate distribution. There were significant differences (P < 0.05) in trunk growth among types of carbohydrates, but no significant differences for carbohydrate concentrations. The mixtures of sucrose and glucose had the largest effect on growth compared to either sugar alone, suggesting that glucose and sucrose alone were used in processes other than trunk growth. 50:50 mixtures caused a greater effect on overall mean growth indices than either sugar alone. Glucose content in twigs and starch in roots were significantly different (P < 0.05) among overall means for concentrations with increased levels found in trees treated with the greatest concentrations. Chlorophyll fluorescence Fv/Fm revealed highly significant differences (P < 0.001) among overall concentrations. Carbon isotope values did not reveal a definite trend that corroborated the exogenous carbohydrate distribution. Results from this experiment suggest that carbohydrate trunk injections can have an impact on growth and vitality of live oak.

Full text

Martínez-Trinidad et al.: Carbohydrate Injections for Live Oaks
©2009 International Society of Arboriculture
142
Carbohydrate Injections as a Potential Option
to Improve Growth and Vitality of Live Oaks
Abstract. This study evaluates the effects of carbohydrate injections on the growth and vitality of live oak (Quercus virginiana P.
Miller). Glucose, sucrose, or a 50:50 mixture of both carbohydrates at increasing concentrations [0, 40, 80, and 120 g/L (0, 5.3,
10.6, and 16.0 oz/gal)] were injected into live oaks. Trunk and root growth, net photosynthesis, root and twig carbohydrate concen-
tration, and chlorophyll fluorescence were monitored. Isotope composition of twig and root samples was measured as an indicator
of injected carbohydrate distribution. There were significant differences (P < 0.05) in trunk growth among types of carbohydrates,
but no significant differences for carbohydrate concentrations. The mixtures of sucrose and glucose had the largest effect on growth
compared to either sugar alone, suggesting that glucose and sucrose alone were used in processes other than trunk growth. 50:50
mixtures caused a greater effect on overall mean growth indices than either sugar alone. Glucose content in twigs and starch in
roots were significantly different (P < 0.05) among overall means for concentrations with increased levels found in trees treated
with the greatest concentrations. Chlorophyll fluorescence Fv/Fm revealed highly significant differences (P < 0.001) among overall
concentrations. Carbon isotope values did not reveal a definite trend that corroborated the exogenous carbohydrate distribution.
Results from this experiment suggest that carbohydrate trunk injections can have an impact on growth and vitality of live oak.
Key Words. Glucose; Quercus virginiana; Sucrose; Sugars; Tree Vitality.
Arboriculture & Urban Forestry 2009. 35(3): 142–147
Tomás Martínez-Trinidad, W. Todd Watson, Michael A. Arnold,
Leonardo Lombardini, and David N. Appel
Photosynthesis in leaves and other chlorophyll-containing tissues
produces carbohydrates, which are converted into energy by res-
piration (Pallardy 2008). Carbohydrates can be used in situ, or
be transported to organs where they are needed or stored for fu-
ture use (Taiz and Zeiger 2006). Trees allocate carbohydrates for
maintenance, reproduction, growth, and/or defense based on en-
vironmental factors and growth stage (Pallardy 2008). Research
has shown that tree growth and vitality depend on carbohydrate
content in tree organs (Wargo et al. 1972; Kolosa et al. 2001).
When trees are affected by stress-inducing factors, carbohydrate
levels can be decreased or depleted, which can have negative re-
percussions on growth and vitality (Gregory and Wargo 1985).
Urban trees are commonly subjected to stressful conditions that
can negatively impact tree vitality. Previous research has shown
that improvement in tree vitality is directly affected by the en-
ergy level in trees (Wargo 1975; Carroll et al. 1983; Percival and
Smiley 2002). Use of inexpensive, nontoxic, and environmentally
friendly products such as sugars could help improve growth and
vitality of trees (Percival 2004; Martínez-Trinidad et al. 2009b).
Trunk injections have been useful for introducing various com-
pounds into trees. The most common types of injections on trees
include bark banding, trunk infusion, and pressurized trunk injec-
tions (Sachs et al. 1977; Sanchez and Fernandez 2004). Trunk
injections are classified as micro- or macroinjections according
to the amount of material injected (Costonis 1981). Macroinfu-
sion is a trunk injection system that has been used for applying
high amounts of solutions into trees while producing minimal
damage (Appel 2001; Eggers et al. 2005). This method makes it
easier to control the amount of sugars injected when using great-
er volumes of solution compared with microinjection systems.
The increase of plant carbohydrate levels as a result of injec-
tions can have an effect on growth and vitality (Abdin et al. 1998;
Iglesias et al. 2001). For sucrose microinjections in fruit trees, re-
search has shown quite variable and unpredictable supplementa-
tion of sucrose into the tree by the microinjection system (Iglesias
et al. 2001). Anecdotal reports of sucrose macroinjections in the
trunk of a large, historic live oak (Quercus virginiana P. Miller)
showed some apparent vitality improvement after being treated
(Giedraitis 1990). Unfortunately, there are no scientific research
studies on macroinjections of carbohydrates in urban trees.
Tree growth is one of the most common indicators used
for studying the effect of environmental factors or treatments
on tree vitality (Dobbertin 2005). The application of carbo-
hydrates through trunk injections may increase the energy
pool and generate greater growth rates (Giedraitis 1990). In-
jected solutions may move up through the xylem, or they may
be stored or translocated to storage tissues (Sachs et al. 1977;
Tattar and Tattar 1999). Considering that exogenous carbohy-
drates can be translocated to different parts of the tree, vari-
ables in addition to growth should be measured to assess tree
vitality and effects caused by carbohydrate supplementation.
Various tools have been suggested for determining tree vi-
tality in the field. The chlorophyll fluorescence parameter Fv/
Fm is often used for measuring the photochemical efficiency of
photosystem II, which indicates the energy level absorbed by
chlorophyll and damage by excess light (Maxwell and Johnson
2000). The Fv/Fm parameter has been suggested as one mea-
surement of tree stress tolerance and tree vitality (Percival and
Sheriffs 2002; Percival and Fraser 2005). An advantage of us-
ing chlorophyll fluorescence measurements is the ease and speed
of collecting data using a portable fluorescence spectrometer.

Arboriculture & Urban Forestry 35(3): May 2009
©2009 International Society of Arboriculture
143
Photosynthesis measurements are also important for providing
additional information about tree vitality and treatment effects.
Carbohydrate injections could affect photosynthetic processes
considering that sugars and water are incorporated into the vas-
cular system and moved up through the canopy (Tattar and Tattar
1999; Percival and Fraser 2005). The effect may be less evident
if sugars are mainly translocated to storage organs such as trunk
or roots. Therefore, tracking carbohydrate content in twigs and
roots can help to determine the effect of exogenous applications.
Sugars extracted from C3 and C4 plants differ in their carbon
isotope ratios δ13C (Fotelli et al. 2003) and when sugar from a
C4 plant (e.g., Zea mays L.) is applied to a C3 plant (e.g., Q. vir-
giniana), the fate of the applied sugar can potentially be traced
within the plant by comparing carbon isotope ratios of treated and
nontreated plants. This information would be useful for determin-
ing the fate and impact of carbohydrate supplementation in trees.
Information about the effects of introducing exoge-
nous carbohydrates as a source of energy might provide ar-
borists with a potential technique to improve the health of ur-
ban trees. The main goals of this investigation were to study
the effects of trunk injections of carbohydrates on growth
and vitality of live oak and to assess the potential for trac-
ing exogenous carbohydrates using carbon isotope ratios.
MATERIALS AND METHODS
Thirty-six established, field-grown live oaks [16–20 cm (6.3–
7.8 in) dbh] grown under similar conditions were used. Similar
trees were selected from a group of nonirrigated trees planted
with 6 m (19.6 ft) spacing in an urban forest near College Sta-
tion, TX in Burleson County (30°33’14.71”N, 96°25’33.61”W).
Trees were growing in a Weswood silty clay loam soil. The site
has an annual mean temperature of 20.3°C (68.5°F), [-1.6°C
(29°F) minimum and 37.7°C (100°F) maximum], and annual
precipitation varies between 762 and 1016 mm (30 and 40 in).
Trunk injections using corn-derived glucose, sucrose, or a
50:50 mixture of glucose and sucrose by weight in three dif-
ferent concentrations [40, 80, and 120 g/L (5.3, 10.6, 16.0 oz/
gal)] were used. Nine trees served as a water-only control, and
three trees were injected for each concentration and type of
carbohydrate. The concentrations were determined accord-
ing to previous research on carbohydrate applications on plants
(McLaughlin et al. 1980; Abdin et al. 1998; Iglesias et al. 2003).
Approximately 10 L (2.6 gal) of solution were injected into the
buttress roots using injection protocols established for inject-
ing trees for oak wilt (Appel 2001; Eggers et al. 2005). Trees
were injected during January 2005 and again in January 2006.
Trunk diameters were measured at 30 cm (12 in) aboveg-
round using a diameter tape (Forestry Suppliers Inc.; Jackson,
MS) and recorded three times during the year throughout the ex-
periment. To avoid possible effects of varying trunk sizes among
trees, a growth index was calculated per year by dividing the ab-
solute increase in trunk diameter in a year by the initial trunk
measurement at the beginning of the experiment (Arnold et al.
2007). Growth index values were used for the statistical analysis.
Four soil holes [15 cm (6 in) deep x 6 cm (2.3 in) diameter]
were dug 1.5 m (4.9 ft) from the trunk and refilled with sandy loam
soil to evaluate root growth. Core samples were extracted using
a core sampler one year after treatment application. An herbicide
(glyphosate) was applied periodically throughout the experiment
to control weeds. Root lengths and average root diameters were
measured using the Winrhizo software® (Regent Instruments
Inc., Québec, Canada). Soil samples were collected annually in
the same location to evaluate new root growth among treatments.
Twig samples were collected three times each year (January,
April, and August) for carbohydrate analysis. Samples were tak-
en from the lowest third of the canopy in all trees. Glucose and
starch content were determined for each sample using Sigma®
GAGO-20 reagents (Sigma®, St. Louis, MO). Glucose was ex-
tracted from tissue in methanol:chloroform:water (MCW, 12:5:3,
v/v/v) solution after centrifugation at 2800 rpm. A 0.5 mL (0.016
fl oz) aliquot of the extract and the glucose standards were mixed
with 5 mL (0.16 fl oz) of anthrone reagent (Jaenicke and Thiong’o
1999). Starch content was determined by enzymatic conversion of
starch to glucose using amyloglucosidase enzyme in the remain-
ing pellet after glucose extraction. Absorbance of samples and
standards were read within 30 minutes with a spectrophotometer
(Spectronic 20, Baush & Lomb, Rochester, NY) set at 625 nm
for glucose and 540 nm for starch (Haissig and Dickson 1979;
Renaud and Mauffette 1991; Martinez-Trinidad et al. 2009a).
Net carbon assimilation was measured in each treatment
using a portable photosynthesis closed system LI-6200 (Li-
Cor®, Lincoln, NE). Carbon assimilation was measured in the
morning on sunny days on the southern side of the canopy.
Three leaves from the lowest third of the canopy were selected.
Chlorophyll fluorescence was measured using a HandyPEA®
portable fluorescence spectrometer (Hansatech Instruments Ltd,
King’s Lynn, UK). Ten leaves from the lower two-thirds of the
canopy were adapted to darkness for 25 minutes. After the dark-
ness period, the fluorescence response was induced by a red light
of 1500µmol/m2/Hz photosynthetically active radiation intensity
provided by an array of 6 light-emitting diodes, with a data acqui-
sition rate of 10 µs for the first 2 ms and 12-bit resolution. The ratio
Fv/Fm was used to estimate tree vitality (Percival and Fraser 2001).
Chlorophyll fluorescence data was taken at January, April, and
August 2005, and January, April, August 2006, and January 2007.
The translocation of carbohydrates was evaluated by deter-
mining carbon isotope compositions. Twigs one-year-old and
buttress roots samples [4 mm (0.15 in) x 100 mm (3.93 in)] were
collected from controls, glucose [40 and 120 g/L (5.3 and 16.0
oz/gal)], and sucrose [40 and 120 g/L (5.3 and 16.0 oz/gal)] treat-
ments 12 months after the first treatment. Samples were submit-
ted for analysis to the Stable Isotope Facility at University of Cal-
ifornia, Davis. The isotope composition was expressed to PeeDee
Belemnite (PDB) carbonate standard (Peterson and Fry 1987).
Table 1. P values from the ANOVA table for diameter growth index,
twig glucose content, root starch content, and chlorophyll fluo-
rescence Fv/Fm for live oaks injected with three sugars (glucose,
sucrose, and a 50:50 mixture) and four concentrations (0, 40, 80,
and 120 g/L-1).
Factors Diameter Twig Root Chlorophyll
growth glucose starch fluorescence
index content content Fv/Fm
Concentration 0.159 0.036 0.001 0.001
Carbohydrate 0.049 0.941 0.881 0.104
Time 0.001 0.001 0.001 0.001
Concentration x carbohydrate 0.532 0.404 0.152 0.216
Concentration x time 0.334 0.469 0.002 0.064
Carbohydrate x time 0.133 0.531 0.627 0.141
Conc. x carb. x time 0.160 0.974 0.209 0.767

Martínez-Trinidad et al.: Carbohydrate Injections for Live Oaks
©2009 International Society of Arboriculture
144
The experimental design was completely randomized us-
ing three replicates per treatment. The data was analyzed us-
ing an augmented factorial structure considering time and
the two-way and three-way interactions in the model (Lent-
ner and Bishop 1986). Because carbon isotope ratio was de-
termined only for some treatments, data were analyzed as a
complete randomized design, and when the main factors were
significant (P < 0.05), mean comparisons were calculated us-
ing Dunnet’s test comparing the treatments with the con-
trol. The results were analyzed using the SPSS v.13 software.
RESULTS AND DISCUSSION
Trunk growth revealed a significant difference (P < 0.05) among
carbohydrates (Figure 1), but not for concentrations. This might
suggest that either the concentrations were insufficient to affect
tree growth or that sugars were used for processes other than
growth. Because trees were not under visibly stressful conditions,
exogenous carbohydrates may have been used for other functions
such as storage, defense, or reproduction (Pallardy 2008). Igle-
sias et al. (2003) found that fruit set in Satsuma mandarin [Citrus
unshiu (Mak.) Marc., cv. Okitsu] increased by 10% when supple-
mented with sucrose. Early studies showed that albino corn (Zea
mays L) survived and produced inflorescences with supplemen-
tation of sucrose through the cut ends of leaves (Spoehr 1942).
The results also indicate the 50:50 mixture of glucose and
sucrose resulted in a small but significant increase in growth
index as compared to sucrose or glucose alone (Figure 1). Su-
crose is the main sugar translocated by phloem, while glucose
is a simple sugar product of photosynthesis and the base unit of
storage carbohydrates (Taiz and Seizer 2006). Trunk injections of
more than one type of sugar in live oaks might have an additive
effect and help trees to utilize carbohydrates better to increase
growth. In other studies, growth was also stimulated in annual
plants such as soybean [Glycine max (L.) Merr.] and corn (Z.
mays) when they were treated with sucrose injections at 300 g/L
(40 oz/gal) (Zhou et al. 1997; Abdin et al. 1998). The amount
injected and size of plants might play an important role in the
potential effect of carbohydrates injected. In addition, research
indicates that carbohydrates such as sucrose and glucose can af-
fect sugar sensing systems that initiate changes in gene expres-
sion, which can cause an effect on plant growth (Koch 1996).
Results for root growth did not reveal significant differences (P
> 0.05) among type of sugars or concentrations. It seems the effect
of injections was greater in the aboveground portions of the tree.
However, the determination of root growth was based on sampling
a small portion of fine roots (four samples per tree), which might
be the reason for the lack of significant differences among the
results due to high variability among samples. Previous research
with soybean [Glycine max (L.) Merr.] and birch (Betula pendula
Roth.) has shown an increase in fine roots as a result of exogenous
applications of sucrose which apparently caused suppression in
photosynthesis and carbon remobilization in favor of enhancing
root development (Abdin et al. 1998; Percival and Fraser 2005).
There were no significance differences (P > 0.05) found in
net carbon assimilation among different sugars or concentra-
tions during the two year period. However, the data showed
high variation, which affected the analysis. Also, trunk in-
jections were performed during the dormant season with
old leaves present before new leaf emergence, which could
have reduced the potential effect on photosynthesis. In soy-
bean plants, Abdin et al. (1998) found that the supplementa-
tion with sucrose by injections suppressed photosynthesis.
Glucose content in twigs and starch in roots were signifi-
cantly greater in trees receiving the highest concentration of
carbohydrate (Figure 2). This result was not unexpected due to
the potential for translocation of exogenously applied carbohy-
drates upward and/or downward from the injection point (Tattar
and Tattar 1999). Prior research showed 14C sucrose infused into
sorghum [Sorghum bicolor (L.) Moench] via a pulse applica-
tion can move upwards through the xylem (Tarpley et al. 1994).
Corn plants (Z. mays) formed abundant starch when treated with
solutions of glucose or sucrose (Spoehr 1942). Similar results
were also found in Satsuma mandarin injected with sucrose,
which resulted in increased levels of starch in fine roots (Iglesias
et al. 2003). The impact of carbohydrate concentrations in this
study was more evident in roots where the greatest concentra-
tions [120 g/L (16 oz/gal)] resulted in greater starch levels com-
pared to the control (Figure 2b). Exogenous carbohydrates could
have been either stored or translocated to the roots (Tattar and
Tattar 1999). High carbohydrate concentrations in other organs
like roots and fruits have been reported for Satsuma mandarin
when sucrose was injected in the trunk (Iglesias et al. 2003).
Chlorophyll fluorescence measures the photochemical effi-
ciency of photosystem II (Maxwell and Johnson 2000) and is
used as a nondestructive diagnostic for plant vitality and stress
(Percival and Sheriffs 2002; Percival 2004; Percival and Boyle
2005). In this study, supplementing trees with carbohydrates via
trunk injections increased Fv/Fm (Figure 3), which suggests a
method to improve live oak vitality. In addition to chlorophyll
fluorescence, similar trends were observed in glucose content
in twigs and starch content in roots in response to carbohy-
drate injection, both used as indicators of tree health (Gregory
and Wargo 1985; Wargo et al. 2002; Dobbertin 2005). However,
given the increase in trunk diameter by only the sugar mixture
treatment, a concomitant response in Fv/Fm and photosynthe-
sis can be expected which may have explained, in part, by the
resultant increase in trunk diameter. Growth of many temperate
trees is dependent on stored labile carbon produced via photo-
Figure 1. Trunk diameter growth indices (cm/cm) of live oaks in-
jected with three different types of sugars (glucose, sucrose, and
a 50:50 mixture). Bars indicate ±1 standard error. Different letters
between types of sugar indicate significant differences (P < 0.05)
using LSD.

Arboriculture & Urban Forestry 35(3): May 2009
©2009 International Society of Arboriculture
145
synthesis in previous years (Barford et al. 2001; Gough et al.
2008). Injections of carbohydrate in this study may have been
stored for future use instead of utilized immediately for growth.
Carbon isotopic ratios (δ13C) in roots did not differ (P >
0.05) among carbohydrates treatments (data not shown), but
there was a significant difference (P < 0.05) in the twigs of
trees receiving 120 g/L (16 oz/gal) (δ13C= -29.157‰) rela-
tive to the control (δ13C= -30.530‰) suggesting the pres-
ence of exogenous carbohydrates in twigs. The lack of dif-
ference in δ13C in twigs of trees receiving glucose indicates
that glucose was metabolized differently from sucrose.
Results from this experiment showed how annual trunk in-
jections of carbohydrates during dormancy may improve growth
and vitality in live oaks. No visual or physiological damage
apart from the injection sites was detected as a result of carbo-
hydrate injections during the time of the experiment. Previous
research showed that carbohydrates can help combat the effect
of stress conditions, such as defoliations (Iglesias et al. 2003).
Based on the results of this study, future research on the effects
of carbohydrate injections in trees subjected to stressful condi-
tions during the growing season should be conducted where
the impact on tree performance may be more pronounced.
LITERATURE CITED
Abdin, O.A., X. Zhou, B.E. Coulman, D. Cloutier, M.A. Faris, and D.L.
Smith. 1998. Effect of sucrose supplementation by stem injection on
the development of soybean plants. Journal of Experimental Botany
49(329):2013–2018.
Appel, D.N. 2001. The use of Alamo for oak wilt management. p. 101–106.
In: C.L. Ash (Ed.). Shade tree wilt diseases. APS Press, St. Paul, MN.
Arnold, M.A., G.V. McDonald, D.L. Bryan, G.C. Denny, W.T. Watson,
and L. Lombardini. 2007. Below-grade planting adversely affects
survival and growth of tree species from five different families. Arbo-
riculture & Urban Forestry 33(1):64–69.
Barford, C.C., S.C. Wofsy, M.L. Goulden, J.W. Munger, E.H. Pyle, S.P.
Urbanski, L. Hutyra, S. R. Saleska, D. Fitzjarrald, and K. Moore.
2001. Factors controlling long- and short-term sequestration of atmo-
spheric CO2 in a mid-latitude forest. Science 294:1688–1691.
Carroll, J.E., T.A. Tattar, and P.M. Wargo. 1983. Relationship of root
starch to decline of sugar maple. Plant Disease 67:1347–1349.
Costonis, A.C. 1981. Tree injections: perspective macro-injection/micro-
injection. Journal of Arboriculture 7(10):275–277.
Dobbertin, M. 2005. Tree growth as indicator of tree vitality and of tree
reaction to environmental stress: a review. European Journal of Forest
Research 124:319–333.
Eggers, J., J. Juzwik, S. Bernick, and L. Mordaunt. 2005. Evaluation of
propiconazole operational treatments of oaks for oak wilt control.
U.S. Dept. Agriculture Forest Service Resp. North Central Research
Station. NC-390.
Fotelli, M.N., H. Rennenberg, T. Holst, H. Mayer, and A. Gebler. 2003.
Carbon isotope composition of various tissues of beech (Fagus syl-
vatica) regeneration is indicative of recent environment conditions
within the forest understory. New Phytologist 159:229–244.
Giedraitis, J. 1990. Treating the treaty oak. p. 159–163. In: P.D. Rodbell
(Ed.) Make our cities safe for trees: proceedings of the fourth urban
forestry conference. American Forestry Association, St. Louis, MO.
Gregory, R.A., and P.M. Wargo. 1985. Timing of defoliation and its effect
on bud development, starch reserves, and sap sugar concentration in
sugar maple. Canadian Journal of Forest Research 16:10–17.
Gough, C.M., C.S. Vogel, H.P. Schmid, H.B. Su, and P.S. Curtis. 2008.
Multi-year convergence of biometric and meteorological estimates of
forest carbon storage. Agriculture and Forest Meteorology 148:158–
170.
Haissig, B.E., and R.E. Dickson. 1979. Starch measurement in plant tissue
using enzymatic hydrolysis. Physiologia Planatarum 47:151–157.
Iglesias, D.J., F.R. Tadeo, E. Primo-Millo, and M. Talon. 2003. Fruit set
dependence on carbohydrate availability in citrus trees. Tree Physiol-
ogy 23:199–204.
Iglesias, D.J., F.R. Tadeo, F. Legaz, E. Primo-Millo, and M. Talon. 2001.
In vivo sucrose stimulation of colour change in citrus fruit epicarps:
Figure 2. Effects of trunk-injected carbohydrates (glucose, su-
crose, and a 50:50 mixture) at four concentrations [0, 40, 80, and
120 g/L (0, 5.3, 10.6, and 16 oz/gal)] on glucose content from twigs
(A) and starch content from roots (B) of live oaks. Bars indicate ±1
standard error. Different letters between types of sugar indicate
significant differences (P < 0.05) using LSD.
Figure 3. Effects of carbohydrates (glucose, sucrose, and a 50:50
mixture) supplemented by trunk injections at four concentrations
[0, 40, 80, and 120 g/L-1 (0, 5.3, 10.6, and 16 oz/gal)] on chlorophyll
fluorescence (Fv/Fm) on live oaks. Bars indicate ± 1 standard er-
ror. Different letters between type of sugars indicate significant
differences (P < 0.05) using LSD.

Martínez-Trinidad et al.: Carbohydrate Injections for Live Oaks
©2009 International Society of Arboriculture
146
interactions between nutritional and hormonal signals. Physiologia
Planatarum 112:244-250.
Jaenicke, H., and M. Thiong’o. 1999. Comparison of two methods for
the routine extraction and quantification of non-structural carbohy-
drates in tree tissues. Journal of Agriculture, Science and Technology.
2(1):46–55.
Koch, K. 1996. Carbohydrate modulated gene expression in plants. An-
nual Review of Plant Physiology and Molecular Biology 47:509-540.
Kolosa, K.R., D.I. Dickmann, E.A. Paul, and D. Parry. 2001. Repeated
insect defoliation effects on growth, nitrogen acquisition, carbohy-
drates, and root demography of poplars. Oecologia 129:65–74.
Lentner, M., and T. Bishop. 1986. Experimental design and analysis. Val-
ley Book Co., Blacksburg, VA.
Martínez-Trinidad, T., W.T. Watson, M.A. Arnold, and L. Lombardini.
2009a. Temporal and spatial glucose and starch partitioning in live
oak. Arboriculture & Urban Forestry 35:53–56.
Martínez-Trinidad, T., W.T. Watson, M.A. Arnold, and L. Lombardini.
2009b. Investigations of exogenous applications of carbohydrates on
the growth and vitality of live oaks. Urban Forestry & Urban Green-
ing 8:41–48.
Maxwell, K., and G.N. Johnson. 2000. Chlorophyll fluorescence - a prac-
tical guide. Journal of Experimental Botany 51(354):659–668.
McLaughlin, S.B., R.K. McConathy, R.L. Barnes, and W.T. Edwards.
1980. Seasonal changes in energy allocation by white oak (Quercus
alba). Canadian Journal of Forestry Research 10:379–388.
Pallardy, S.G. 2008. Physiology of woody plants. 3rd Ed. Academic
Press, New York.
Percival, G.C. 2004. Evaluation of physiological test as predictors
of young tree establishment and growth. Journal of Arboriculture
30(2):80-91.
Percival, G.C., and S. Boyle. 2005. Evaluation of microcapsule trunk in-
jections for the control of apple scab and powdery mildew. Annals of
Applied Biology 147:119–127.
Percival, G.C., and G.A. Fraser. 2001. Measurement of the salinity and
freezing tolerance of Crataegus genotypes using chlorophyll fluores-
cence. Journal of Arboriculture 27(5):233–245.
Percival, G.C., and G.A. Fraser. 2005. Use of sugars to improve root
growth and increase transplant success of birch (Betula pendula
Roth). Journal of Arboriculture 31(2):66–77.
Percival, G.C., and C.N. Sheriffs. 2002. Identification of drought-tolerant
woody perennials using chlorophyll fluorescence. Journal of Arbori-
culture 28(5):215–223.
Percival, G.C., and T. E. Smiley. 2002. One lump or two. Grounds Main-
tenance 37(4):18–20.
Peterson, J.P., and B. Fry. 1987. Stable isotopes in ecosystem studies.
Annual Review of Ecology and Systematics 18:293–320.
Renaud, J.P., and Y. Mauffette. 1991. The relationship of crown dieback
with carbohydrate content and growth of sugar maple (Acer saccha-
rum). Canadian Journal of Forest Research 21:1111–1118.
Sachs R.M., G. Nyland, W.P. Hackett, J. Coffelt, J. DeBie, and G. Gian-
inni. 1977. Pressurized injection of aqueous solutions into tree trunks.
Scientia Horticulturae 6:297–310.
Sanchez-Zamora, M.A., and R. Fernandez-Escobar. 2004. Uptake and
distribution of trunk injections in conifers. Journal of Arboriculture
30(2):73–79.
Spoehr, H.A. 1942. The culture of albino maize. Plant physiology
17:397–410.
Taiz, L. and E. Zeigher. 2006. Plant physiology. 4th Ed. Sinauer Associ-
ates Inc., Sunderland, MA.
Tarpley, L., D.M. Vietor, and F.R. Miller. 1994. Internodal compartmen-
talization of stem infused 14C sucrose in sweet and grain sorghum.
Crop Science 43:1116–1120.
Tattar, T.A., and S.J. Tattar. 1999. Evidence for the downward movement of
materials injected into trees. Journal of Arboriculture 25(6):325–328.
Wargo, P.M. 1975. Estimating starch content in roots of deciduous trees-
a visual technique. U.S. Dept. Agriculture Forest Service Research
Paper NE. 313. Upper Darby, PA.
Wargo, P.M., R. Minocha, B.L. Wong, R.P. Long, S.B. Horsley, and T.J.
Hall. 2002. Measuring changes in stress and vitality indicators in
limed sugar maple on the Allegheny Plateau in north-central Pennsyl-
vania. Canadian Journal of Forest Research 32:629–641.
Wargo, P.M., J. Parker, and D.R. Houston. 1972. Starch content in roots
of defoliated sugar maple. Forest Science 18:203–204.
Zhou, X.M., P. Dutilleul, A.F. MacKenzie, C.A. Madramootoo, and D.L.
Smith. 1997. Effects of stem-injected sucrose on grain production,
dry matter distribution, and chlorophyll fluorescence of field-grown
corn plants. Journal of Agronomy and Crop Science 178:65–71.
Acknowledgments. We thank the Texas Forest Service and the USDA
Forest Service for supporting this research.
Tomás Martínez-Trinidad (corresponding author)
Colegio de Postgraduados – Programa Forestal
Km. 36.5 Carr. Mex-Tex. Montecillo
Texcoco, Edo. de Mexico. 56230. Mexico.
tomtz@colpos.mx
W. Todd Watson
Department of Ecosystem Science & Management
Texas A&M University
College Station, TX 77843-2138, U.S.
t-watson@tamu.edu
Michael A. Arnold
Department of Horticultural Sciences
Texas A&M University
College Station, TX 77843-2133, U.S.
ma-arnold@tamu.edu
Leonardo Lombardini
Department of Horticultural Sciences
Texas A&M University
College Station, TX 77843-2133, U.S.
l-lombardini@tamu.edu
David N. Appel
Department of Plant Pathology & Microbiology
Texas A&M University
College Station, TX 77843-2132, U.S.
appel@ag.tamu.edu

Arboriculture & Urban Forestry 35(3): May 2009
©2009 International Society of Arboriculture
147
Résumé. Cette étude évalue les effets des injections d’hydrates de car-
bone sur la croissance et la vitalité de chênes verts (Quercus virginiana P.
Miller). Des injections de glucose, de sucrose ou d’un mélange 50:50 de
ces deux hydrates de carbone à des concentrations de 0, 40, 80 et 120 g/L
ont été faites dans les chênes verts. La croissance du tronc et des racines,
la photosynthèse nette, la concentration en hydrate de carbone dans les
racines et les pousses, et la fluorescence de la chlorophylle ont été suivis
et mesurés. La composition en isotopes d’échantillons de pousses et de
racines a été mesurée en tant qu’indicateur de la distribution des hydrates
de carbone injectés. Il y avait des différences significatives (P<0,05) dans
la croissance du tronc parmi les différents types d’hydrates de carbone,
mais aucune différence significative dans la concentrations en hydrates
de carbone. Les mélanges de sucrose et de glucose avaient les effets les
plus importants comparés à ceux avec un seul sucre, ce qui suggère que
le glucose et le sucrose seuls sont utilisés dans des processus autres que
celui de la croissance du tronc. Les mélanges 50:50 résultaient en un
plus grand effet sur l’ensemble des indices de croissance que les sucres
pris seuls. Les contenus en glucose des pousses et de l’amidon dans les
racines étaient significativement différents (P<0,05) parmi toutes les
moyennes de concentrations avec des niveaux accrus observés chez les
arbres traités avec les plus grandes concentrations. La fluorescence de
la chlorophylle Fv/Fm a révélé des différences significatives (P<0,001)
à toutes les concentrations. Les valeurs d’isotopes de carbone n’ont pas
permis de révéler une tendance définitive qui corroborerait la distribu-
tion exogène des hydrates de carbone. Les résultats de cette expérience
suggèrent que les injections d’hydrates de carbone dans le tronc peuvent
avoir un impact sur la croissance et la vitalité du chêne vert.
Zusammenfassung. Diese Studie bewertet die Effekte von Kohlen-
hydrat-Injektionen auf das Wachstum und die Vitalität von Lebenseichen.
Glukose, Sukrose oder eine 50:50 Mischung aus beiden Kohlenhydraten
mit ansteigenden Konzentrationen (0, 40, 80 und 120 g/L) wurden in
die Lebenseichen injiziert. Stamm- und Wurzelwachstum, Nettophoto-
synthese, Wurzel- und Zweigkohlenhydratkonzentration und die Chlo-
rophyllfluoreszenz wurden überwacht. Die Isotopenzusammenstellung
von Zweig- und Wurzelproben wurde als Indikator der Verteilung der
injizierten Kohlenhydrate gemessen. Es gab signifikante Unterschiede
(P<0.05) im Stammwachstum bei den unterschiedlichen Kohlehydraten,
aber keine signifikanten Unterschiede bei den Konzentrationen. Die Mis-
chung von Sukrose und Glukose hatte den größten Wachstumseffekt im
Vergleich zu den Einzelzuckern, was schließen lässt, die Einzelzucker
eher in anderen Prozessen als Wachstum zu verwenden. 50:50 Mischun-
gen verursachten einen größeren Effekt auf das Durchschnittswachstum
als Einzelzucker. Der Glukosegehalt in Zweigen und Stärke in Wurzeln
waren deutlich unterschiedlich (p<0.05), während steigende Raten in
Bäumen, die mit der höchsten Konzentration behandelt wurden. Die
Chlorophyllfluoreszenz Fv/Fm enthüllte hochsignifikante Unterschiede
(p<0.001) bei allen Konzentrationen. Die Karbonisotopenwerte zeigten
keinen definitiven Trend, welcher mit der exogenen Kohlenhydratkonzen-
tration zusammenhängt. Die Ergebnisse dieses Experiments zeigen, dass
Stamminjektioen mit Kohlenhydraten einen Einfluss auf das Wachstum
und Vitalität von Lebenseichen haben.
Resumen. Este estudio evaluó los efectos de inyecciones de carbo-
hidratos en el crecimiento y vitalidad de encinos siempreverdes (Quer-
cus virginiana P. Miller). Se inyectó en encinos glucosa, sucrosa, o una
mezcla 50:50 de los dos carbohidratos a concentraciones [0, 40, 80, y
120 g/L (0, 5.3, 10.6, y 16.0 oz/gal)]. Se monitoreó el crecimiento del
tronco y raíz, fotosíntesis neta, concentraciones de carbohidratos en raíz
y brotes y fluorescencia de clorofila. Se midió la composición de isótopos
de tallos y muestras de raíz como un indicador de la distribución de los
carbohidratos inyectados. Hubo diferencias significativas (P < 0.05) en el
crecimiento del tronco entre los tipos de carbohidratos, pero no fueron
significativas para las concentraciones de carbohidratos. Las mezclas
de sucrosa y glucosa tuvieron el efecto más grande en el crecimiento
comparado con solamente azúcar, sugiriendo que la glucosa y la sucrosa
solas fueron usadas en procesos diferentes al crecimiento del tronco. Las
mezclas 50:50 causaron un mayor efecto en los índices medios de cre-
cimiento que solamente el azúcar. El contenido de glucosa en los tallos
y almidón en raíces fue significativamente diferente (P < 0.05) entre las
medias para las concentraciones con niveles altos encontrados en árboles
tratados con las concentraciones más altas. La fluorescencia de clorofila
Fv/Fm reveló diferencias altamente significativas (P < 0.001) entre las
concentraciones promedio. Los valores de los isótopos de carbono no
revelaron una tendencia definida que corroborara la distribución exógena
de carbohidratos. Los resultados de este experimento sugieren que las
inyecciones al tronco de carbohidratos puede tener un impacto en el cre-
cimiento y vitalidad de un encino.