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Influence of rootstockson ‘Orlando’ tangelo leafelemental concentrationEsmaeil Fallahi a , Robin E. Mason b & D. RossRodney ba Southwest Idaho Research and ExtensionCenter , University of Idaho , 29603 U of ILane, Parma, Idaho, 83660b Yuma Agricultural Center , University ofArizona , Rt 1 Box 40‐M, Somerton, Arizona,85350Published online: 11 Nov 2008.

To cite this article: Esmaeil Fallahi , Robin E. Mason & D. Ross Rodney (1991)Influence of rootstocks on ‘Orlando’ tangelo leaf elemental concentration,Communications in Soil Science and Plant Analysis, 22:11-12, 1047-1057, DOI:10.1080/00103629109368473

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COMMUN. IN SOIL SCI. PLANT ANAL., 22(11&12), 1047-1057 (1991)

INFLUENCE OF ROOTSTOCKS ON 'ORLANDO' TANGELO LEAFELEMENTAL CONCENTRATION

Esmaeil Fallahi1, Robin E. Mason2 and D. Ross Rodney2

1Southwest Idaho Research and Extension Center, University of Idaho, 29603 Uof I Lane, Parma, Idaho 83660

2Yuma Agricultural Center, University of Arizona, Rt 1 Box 40-M, Somerton,Arizona 85350

ABSTRACT: The influence of 10 rootstocks on leaf elemental

concentrations and their relationship with yield, tree growth, leaf fresh

weight and dry matter of 'Orlando' tangelo (C. parodisi Macf. x C. reticulata

Blanco) was studied under the arid climate of southwestern Arizona.

'Orlando' tangelo trees on Carrizo citrange [(C sinensis (L.) Osbeck x

Poncirus trifoliata (L.) Raf.], Yuma citrange (P. trifoliata x C. sinensis),

Taiwanica (C. taiwanica) and Volkamer lemon (C. limon Burm f.) had larger

canopy and higher yield than the trees on Savage citrange (P. trifoliata x C.

sinensis), Ichang pummelo (C. ichangensis hyb.) and Palestine sweet lime (C.

limettoides Tan.). Leaves of trees on Carrizo citrange were heavier but those

on Savage citrange had higher percent dry matter than those on other

rootstocks. Trees on macrophylla (Alemow) (C macrophylla Wester) had

significantly higher leaf N and Mn while those on Carrizo, Yuma and Savage

citranges had lower leaf N than the trees on other rootstocks. Trees on

Volkamer lemon, rough lemon (C. jambhiri Lush), macrophylla and

Palestine sweet lime had low leaf K but high leaf Mg. 'Orlando' trees on

Carrizo citrange had the highest leaf Mg and Cu but the lowest leaf Mn.

Considering mineral (elemental) uptake efficiency, tree growth and/or yield,

Carrizo citrange, Volkamer lemon, Yuma citrange, rough lemon and

Taiwanica are desirable for 'Orlando' tangelo under the arid conditions and

sandy soils of the southwest United States. Macrophylla could only be used

1047

Copyright © 1991 by Marcel Dekkcr, Inc.

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1048 FALLAHI, MASON, AND RODNEY

for a short term planting, while Savage citrange, Batangas mandarin (C.

reticulata Blanco), Ichang pummelo and Palestine sweet lime are not

recommended for planting under the arid conditions similar to those of this

experiment.

INTRODUCTION

The effect of rootstock on yield and growth has been reported for

various citrus cultivars (3,5,6,15,16,17,18). Effects of rootstock on scion leaf

elemental composition have been reported for oranges (10,13), grapefruits

(15,16,17,19), and mandarins (7,10,13). Castle and Krezdorn (2) studied the

effect of ten rootstocks on 'Orlando' tangelo yield, leaf elements and root

distribution in Florida and reported that rough lemon had deeper roots with

more feeder roots than other rootstocks. They also reported that leaves of

'Orlando' tangelo trees on Palestine sweet lime and rough lemon showed a

higher level of leaf N and K but a lower level of leaf Mg than those on other

tested rootstocks. Smith (13) reported that 'Orlando' tangelo leaf had lower

concentrations of leaf N and K than 'Satsuma', 'Robinson', 'Page' or 'Bower'

mandarins. He also reported that mandarin trees on Carrizo citrange had

higher leaf N, Mg, and Cu, but lower leaf P, K and Mn than those on rough

lemon rootstock.

Arizona produced a total of 126,000 MT of tangerines and tangelos

from 1,700 hectares between 1983-1988 (1). However, there have been no

comprehensive studies in Arizona evaluating effects of various rootstocks on

leaf elemental status of 'Orlando' tangelo. Our objective was to evaluate

effects of ten rootstocks on leaf elemental concentrations and the

relationship between leaf elements, leaf dry matter, yield and tree growth of

'Orlando' tangelo grown in the desert southwest of the United States. The

rootstocks evaluated and climatic conditions in this experiment are different

from those of Castle, and Krezdorn (2) and Smith (13) in Florida. This study

enabled us to identify the mineral uptake efficiency of different rootstocks

and to identify potential rootstocks for 'Orlando' tangelo for the arid regions

of the southwestern United States.

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INFLUENCE OF ROOTSTOCKS 1049

MATERIALS AND METHODS

'Orlando' tangelo was budded on ten rootstocks. Trees were grown in

containers in the greenhouse and planted in the field in March 1970. The ten

rootstocks were: Carrizo citrange, Yuma citrange, Taiwanica, Volkamer

lemon, rough lemon, Batangas mandarin, Savage citrange, macrophylla,

Ichang pummelo, and Palestine sweet lime. The budwood sources and

budded trees were indexed and were free of viruses. Tree spacing was 7 x 7

m, the soil was a well drained deep sand with the top 20 cm mixed with silt

classified as Superstition sand (Typic Calciorthid, 80% sand). The soil pH

was 8.0 due to high Na and Ca content. 'Fairchild' tangerine [(C reticulata

Blanco) x (C. parodist Macf.)] was planted around the experimental block

which served as a pollinizer for 'Orlando' tangelo.

Ammonium nitrate was applied in four equal applications in October,

December, February and April every year at an annual rate of 0.5 to 1.2 kg

N/tree, depending on tree age. Nitrogen was applied at an annual rate of 1.2

kg/tree for the last 5 years (1984-1988). Trees were flood irrigated biweekly

from April through September and monthly from October through March.

Trees were not given any micronutrients after 1984 to evaluate rootstock

mineral uptake efficiency. Pesticide was applied twice annually to control

thrips and the orchard was disked as needed for weed control. Overall, tree

spacing and other cultural practices in the experimental block were similar to

those used in commercial groves.

The experimental design was a randomized complete block with four

blocks (replications) and two trees per plot (total of 8 trees per rootstock).

Fruit from each tree was harvested into 30 kg boxes and yield was recorded

annually from 1982 through 1988. Cumulative yields were calculated for the

years of 1982 through 1988 (7-year cumulative yield). Tree volume was

calculated by Turrell's formula (14) using measurements of tree height and

width: V=0.542 x height x width2.

In mid-August of 1987 and 1988, thirty leaves per tree were sampled

randomly from the last 6 month's growth of the non-bearing shoots. Leaves

were washed in a mild liqui-nox detergent, rinsed with distilled water and

dried in an air forced oven at 70°C to reach a constant weight. Leaves were

then analyzed for N by a Kjeldahl method (9). Potassium, Ca, Mg, Fe, Zn,

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1050 FALLAHI, MASON, AND RODNEY

Mn and Cu were determined by dry ashing following the procedures

described by Jones (8) and measuring by an atomic absorption (Video II,

Allied, Waltham, MA). Analyses of variance for cumulative yield over 7

years, tree canopy volume for 1988 and for 2-year averages (1987 and 1988)

for leaf fresh weight, dry matter and elements are reported. Mean

separations were computed with Duncan's multiple range test when a

significant F value existed.

RESULTS AND DISCUSSION

The trees on the rootstocks are ranked in Table 1 according to their

tree canopy volume. Since the effects of rootstocks on scion leaf fresh weight,

dry weight, dry matter and leaf elements in both 1987 and 1988 were similar,

the analyses of variance for 2-year averages of leaf weight (Table 1) and

mineral elements are reported (Table 2).

Canopy volume and cumulative yield of 'Orlando' tangelo on Carrizo

citrange, Yuma citrange, Taiwanica and Volkamer lemon were statistically

similar, but were significantly larger than those on Savage citrange, Ichang

pummelo, and Palestine sweet lime (Table 1). In general, in each tree yield

was proportional to the tree canopy volume (Table 1).

Leaves of 'Orlando' tangelo trees on Carrizo citrange were

significantly heavier and contained higher dry matter than those on Batangas

mandarin, Ichang pummelo and Palestine sweet lime (Table 1). Leaves of

trees on Savage citrange had a higher percent dry matter than those on all

other rootstocks (Table 1). The high percent dry matter in the leaf (Table 1)

and high soluble solids in the fruit (5) of 'Orlando' tangelo trees on Savage

citrange may indicate a higher photosynthesis efficiency in the trees on this

rootstock. 'Orlando' leaf elemental concentrations were not drastically

diluted by their dry matter content (Tables 1 and 2).

'Orlando' tangelo trees on macrophylla had significantly higher leaf N,

while those on citranges (Carrizo, Yuma and Savage) had relatively lower

leaf N than those on other rootstocks (Table 2). Leaf N in 'Orlando' trees on

Palestine sweet lime was higher than leaf N in those on Carrizo citrange

(Table 2) which is in agreement with Castle and Krezdorn in Florida (2).

However, leaf N from trees on rough lemon was significantly higher than that

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TABLE 1

Influence of rootstock on tree canopy volume, yield and leaf fresh weight and dry matter in 'Orlando' tangelo.2

Rootstockv

CARYUMTAIVOLRLEBATSAVMACICHPAL

Treecanopyvolume

1988

(m3)

112.7 a107.7 a95.4 ab94.6 ab89.9 abc69.4 bed62.9 cd61.3 cd52.6 d40.7 d

Cumulativeyield

1982-88

(kg/tree)

1002 a1052 a969 a950 a959 a694 b692 b828 a653 b623 b

Leaf freshweight

(g/leaf)

0.455 a0.428 abc0.439 abc0.444 ab0.429 abc0.389 de0.406 cde0.424 abed0.410 bede0.376 e

Leaf drymatter

(g/leaf)

0.178 a0.168 ab0.175 a0.175 a0.170 ab0.150 c0.167 ab0.168 ab0.160 be0.152 c

Leaf percentdry matter

39.1 cd39.4 bed39.8 be39.2 cd39.6 be38.5 d41.2 a39.5 bed39.0 cd40.3 b

z Each value of the leaf fresh matter, dry weight and percent dry matter is the mean of 1987 and 1988 data with fourtwo-tree replications per year.

y Abbreviations: CAR=Carrizo citrange; YUM= Yuma citrange; TAI=C. taiwanica; VOL=Volkamer lemon;RLE=rough lemon; BAT=Batangas mandarin; SAV=Savage citrange; MAC=C. macmphylla; ICH = Ichangpummelo; PAL=Palestine sweet lime.

Z

I•z9

3

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-- TABLE 2

Effects of rootstock on leaf elemental concentrations of 'Orlando' tangelo expressed on a dry weight basis.2

Rootstockv

CARYUMTAIVOLRLEBATSAVMACICHPAL

N(%)

2.25 e2.40 d2.48 cd2.59 be2.60 be2.49 cd2.46 d2.72 a2.51 cd2.68 ab

K(%)

1.23 c1.47 ab1.28 be.88 d.78 d

1.58 a1.19 c.88 d

1.40 abc.70 d

Ca(%)

4.99 ab4.82 abc4.91 abc4.26 c4.45 be4.30 c5.13 a4.27 c4.48 be4.59 abc

Mg(%)

.62 a

.50 cd

.48 d

.57 ab

.56 abc

.47 d

.47 d

.51 bed

.45 d

.58 a

Cu(ppm)

13.59 a9.64 be

10.46 be9.90 be9.12 c

10.91 be11.29 b9.32 c9.12 c6.92 d

Zn(ppm)

22.18 a24.40 a22.96 a25.56 a26.11 a23.39 a22.28 a25.47 a25.28 a23.54 a

Mn(ppm)

8.57 f13.14 d10.44 e15.76 be14.26 cd11.30 e10.86 e18.25 a14.87 be16.20 b

Fe(ppm)

37.14 d38.72 d38.66 d49.39 be45.91 cd36.41 d40.14 cd57.37 ab59.66 a39.82 cd

2p>>

z Each value is the mean of 1987 and 1988 data with four two-tree replications per year. §

y Abbreviations: CAR=Carrizocitrange; YUM=Yumacitrange;TAI=C. taiwanica; VOL=Volkamer lemon; ^RLE=Rough lemon; BAT=Batangas mandarin; SAV=Savage citrange; MAC=C macrophylla; ICH=Ichang Opummelo; PAL=Palestine sweet lime. 5

a

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INFLUENCE OF ROOTSTOCKS 1053

of Carrizo citrange (Table 2) which contradicts the previous study (2) where

trees on these 2 rootstocks had a similar leaf N. Canopy and root volume of

'Orlando' tangelo trees on rough lemon were similar to those on Palestine

sweet lime but significantly larger than those on Carrizo citrange in Florida

(2). However, in our experiment, trees on rough lemon and Carrizo citrange

had similar canopy volume but were larger than those on Palestine sweet

lime (Table 1). Soil textures in our experiment and in Florida (2) were

similar. Thus, if we assume that the root volume of trees on rough lemon in

our experiment was bigger than that of Carrizo citrange as was the case in

Florida (2), then 'Orlando' tangelo trees on rough lemon should have a

larger root/canopy ratio than that of trees on Carrizo citrange in Arizona.

This high root/canopy ratio could be the reason for the higher N uptake in

the trees on rough lemon than of those on Carrizo citrange (Table 2). The

relative differences in the tree canopy size between trees on rough lemon and

Carrizo citrange in our experiment which differs from the previous study (2)

could be due to the stion (cultivar/rootstock)-environment interactions or

environmental (i.e. temperature and relative humidity) differences between

Arizona.and Florida.

Trees on Palestine sweet lime and macrophylla had lower leaf K,

perhaps due to their higher leaf N, than those on other rootstocks (Table 2).

Antagonism between citrus leaf N and K was previously reported (12).

However, low leaf K was also observed in the trees on Volkamer lemon and

rough lemon (Table 2) which is possibly due to the high yield of trees on

these rootstocks (Table 1). High yielding trees require more K for fruit

production; thus, less K will be deposited in the leaf (11). Trees on

Batangas mandarin had significantly higher leaf K than those on Carrizo and

Savage citranges, Taiwanica, Volkamer lemon rough lemon, macrophylla and

Palestine sweet lime (Table 2). Trees on Savage citrange had significantly

higher leaf Ca than those on Volkamer lemon, rough lemon, macrophylla,

Batangas mandarin, and Ichang pummelo (Table 2).

Leaf Mg concentration in the trees on most rootstocks were negatively

correlated to their K concentration. Therefore, trees on Batangas mandarin

and Ichang pummelo had lower leaf Mg while those on Palestine sweet lime

had higher leaf Mg than those on most other rootstocks (Table 2). However,

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1054 FALLAHI, MASON, AND RODNEY

leaves from trees on Carrizo showed a high level of leaf Mg in spite of their

moderately high leaf K (Table 2).

Leaves from trees on Carrizo citrange had significantly higher leaf Cu

while those on Palestine sweet lime had lower leaf Cu than those on other

rootstocks (Table 2). No significant differences were found in the leaf Zn

status of trees on different rootstocks (Table 2). Leaf Mn in trees on

macrophylla was significantly higher, but those on Carrizo citrange were

lower than those on other rootstocks (Table 2). A low level of leaf Mn was

also reported in the leaf of 'Coorg' and 'Kinnow' mandarins on Carrizo

citrange in India (7) which agrees with our results. This suggests that Carrizo

citrange could be suitable in the high-Mn and acidic soil where excess Mn

may cause leaf toxicity. Trees on macrophylla and Ichang pummelo had

significantly higher leaf Fe than those on all citranges, rough lemon,

Taiwanica, Batangas mandarin and Palestine sweet lime (Table 2).

CONCLUSION

In the selection of a rootstock, several physiological and horticultural

characteristics of the scion cultivar on each rootstock, including efficiency of

mineral uptake and transport to the leaf tissue, yield, growth and fruit quality

should be considered. Carrizo citrange is a desirable rootstock for 'Orlando'

tangelo because trees on this rootstock had high production and high leaf Mg

and Cu (Table 2) and produced high quality and heavy fruit (5). However,

the N uptake efficiency of Carrizo rootstock was low and leaf N of 'Orlando'

trees on this rootstock showed marginally sufficient N levels (Table 2)

according to the citrus leaf standard values (12). A higher amount of N than

the rate applied in this experiment (1.2 kg/tree) should be applied if Carrizo

rootstock is used for 'Orlando' tangelo in sandy soils. Although leaf Mn and

Fe levels in the leaves from 'Orlando' tangelo trees on Carrizo citrange were

relatively lower than those on most other rootstocks, no visual chlorotic

symptoms were seen in the trees. These two mineral elements should be

amended in the annual nutrient spray schedule.

Volkamer lemon and rough lemon are desirable rootstocks for

'Orlando' tangelo. Although 'Orlando* fruit from trees on these rootstocks

contained low soluble solids (5), the trees were productive and leaves had

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INFLUENCE OF ROOTSTOCKS 1055

sufficient N levels (Table 2) based on the citrus leaf standard values (12).

However, leaves of 'Orlando' tangelo trees on Volkamer lemon and rough

lemon had very low K concentrations; thus, it is essential to apply K fertilizer

when these 2 rootstocks are used for 'Orlando' tangelo under the condition

of this experiment. Yuma citrange and Taiwanica are also acceptable

rootstocks for 'Orlando' tangelo. Trees on these rootstocks were productive

and had relatively high levels of most tested leaf elements.

'Orlando' tangelo on macrophylla may only be recommended for a

short term planting. Trees on this rootstock are precocious (5) and the

rootstock is very efficient in N uptake (Table 2). High N uptake efficiency

under the sandy soil conditions of this experiment is very beneficial.

However, 'Orlando' trees on macrophylla decline over time as a result of

sieve tube necrosis (4, 5), making this rootstock unacceptable for a long term

planting. Use of potassium fertilizer is essential when macrophylla is used

because the leaf K of the 'Orlando' tangelo trees on this rootstock was low

(Table 2). 'Orlando' tangelo trees on Savage citrange produced fruit with

high sugar (5). Savage citrange, Batangas mandarin, Ichang pummelo or

Palestine sweet lime are not recommended for 'Orlando' tangelo because

trees on these rootstocks produce low yield (Table 1) and/or poor quality

(5).

ACKNOWLEDGEMENTS

The authors wish to thank Ms. Brenda R. Simons, Mr. Phil Tilt and

Mr. Herbert H. Conner for their assistance in different parts of this project.

REFERENCES:

1. Arizona Agricultural Statistics for 1988. Arizona AgriculturalStatistics Service. Phoenix, Arizona. Bull. S-24:64.

2. Castle, W.S. and A.H. Krezdorn. 1975. Effect of citrus rootstocks onroot distribution and leaf mineral content of 'Orlando' tangelo trees.J. Amer. Soc. Hort. Sci. 100(1):1-4.

3. Fallahi, E., J.W. Moon, Jr. and D.R. Rodney. 1989. Yield and qualityof 'Redblush' grapefruit on twelve rootstocks. J. Amer. Soc. Hort. Sci.114(2):187-190.

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11. Smith, P.F. 1966. Citrus nutrition, pp. 174-207. IN: N. Childers (ed.)Fruit Nutrition. Somerset Press, Inc., Somerville, NJ.

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13. Smith, P.F. 1975. Effect of scion and rootstock on mineralcomposition of mandarin-type citrus leaves. J. Amer. Soc. Hort. Sci.100(4):368-369.

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15. Wutscher, H.K. and D. Dube. 1977. Performance of young nucellargrapefruit on 20 rootstocks. J. Amer. Soc. Hort. Sci. 102(3):267-270.

16. Wutscher, H.K. and A.V. Shull. 1972. Performance of 13 cultivars asrootstocks for grapefruit. J. Amer. Soc. Hort. Sci. 97(6):778-781.

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