A mathematical approach for evaluating iron chlorosis inducing factors

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A mathematical approachfor evaluating iron chlorosisinducing factorsA. Booss a , W. Höfner a & K. Schaller ba Institut für Pflanzenernährung der UniversitätGießen, Gießen, 6300, West Germanyb Forschungsanstalt für Weinbau, Gartenbau,Gatränketech‐nologie und Landespflege,Geisenheim, 6222, West GermanyPublished online: 21 Nov 2008.

To cite this article: A. Booss , W. Höfner & K. Schaller (1984) A mathematicalapproach for evaluating iron chlorosis inducing factors, Journal of Plant Nutrition,7:11, 1605-1622

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JOURNAL OF PLANT NUTRITION, 7(11), 1605-1622 (1984)

A MATHEMATICAL APPROACH FOR EVALUATING IRON CHLOROSIS

INDUCING FACTORS

A. Booss1, W. Höfner1, and K. Schaller2

Institut für Pflanzenernährung der Universität Gießen,

6300 Gießen, West Germany

2Forschungsanstalt für Weinbau, Gartenbau, Gatränketech-

nologie und Landespflege

6222 Geisenheim, West Germany

KEY WORDS: Grape vines, chlorosis, water soluble phos-

phorus, HCO3-,factor analysis

ABSTRACT

Factors inducing Fe-chlorosis in grape vines had been

studied during a 2 years field review.

Based on soil and leaf samples, taken consecutively

every two weeks over the whole vegetation period, the va-

riable parameters were determined. The comparison was

achieved between chlorotic and nonchlorotic stands of

grape vines, differing in rootstocks but grafted with the

same cultivar.

By means of different statistical methods, the in-

fluence of the sole parameters were tested.

Chlorosis in its different intensities was'neither

induced by an absolut Fe-deficiency (in leaf or soil) nor

1605

Copyright © 1984 by Marcel Dekker, Inc. 0190-4167/84/0711-1605$3.50/0

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1606 BO0SS, HOFNER, AND SCHALLER

by a relative Fe-deficiency in the soil, as shown by the

amounts of DTPA-extractable Fe.

In spite of this fact, the concentration of water and

citrate buffer-extractable Fe in leaves was in most cases

lower, while the 0,5 n HC1- and 1,0 n HCl-extractable Fe

was higher in chlorotic leaves compared with green ones.

All of the applied statistical methods proved in accor-

dance the important influence of water soluble phosphate in

the soil layer between 20 and 60 cm. The comparison with

additional results from field surveys primarily points to

a complex acting through HCO3- -Pw on and energy status

during the development of the physiologically induced iron-

chlorosis.

INTRODUCTION

Although there is a wide range of engaged and specia-

lized researches, the reasons of chlorosis due to physiolo-

gical Fe-deficiency are still a matter of discussion.

Especially in grape growing areas Fe-chlorosis causes

considerable yield depressions when appearing at early

stages of growth, but no recent data are available in this

respect (Booss et al., 1982). There is convincing evidence

in the literature about the initiating effect of high HCO ~-

concentrations upon the chlorosis on alkaline soils, where

a low availability of Fe in the soil solution has also to

be considered as a chlorosis factor (Rutland and Bukovac,

1971; Boxma, 1972; Venkatraju and Marschner, 1981). But

there are also many reports, showing the importance of high

P-levels (Brown and Jones, 1975; Patel et al. , 1976; Olsen

and Brown, 1980) or the interaction between high P- and

HCO,.. -levels, which may also induce iron chlorosis (Brown

et al., 1959; Booss, 1983). An observation typical for soils

rich in CaCO is the high concentration of total Fe in chlo-

rotic grape-vine leaves, very often exceeding the Fe-con-

tent of healthy ones (Scholl, 1979; Booss et al., 1982).

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IRON CHLOROSIS 1607

To understand the Fe-status of leaves more correctly,

a modified method according to Oserkowsky (1933) is ge-

nerally used extracting leaves with diluted HC1. But it

has to be noted, that method in many cases did not prove

suitable (Booss et al., 1983) or that its results were

depending on the sampling time (Booss et al., 1982).

The aim of the following work was to evaluate those

factors, which are generally discussed as inducing iron-

chlorosis. For this reason the results of a 2 years re-

search program had been evaluated by using different me-

thods of statistics.

MATERIALS AND METHODS

Investigations were done in a 12 years old field trial

with different rootstocks, all grafted with Riesling (Klon

239 Geisenheim). Ten different rootstock/scion combinations

(4 susceptible, 6 resistent to chlorosis) were selected.

Soil and leaf samples were taken from "green" and "chloro-

tic" plants. The soil was classified as "Loess" with 15 %

CaCO3 and pH (KC1) 7,8. Soil samples were taken at 8 con-

secutive samplings, starting in April with a 14 days inter-

val from upper soil (0 - 20 cm) and lower soil (20 - 60 cm).

Leaf samples, composed of 4 and 5 leaves (from the top

of branches) were taken parallel to the sampling of soils,

but starting in may after budbreak. For every sampling

time the following parameter had been determined:

1. Soil: Water content, pH (1 n KC1), HCO "-concentration

in field moist soil (Boxma, 1972); water soluble P (P )

(Sissingh, 1971); Fe, Cu, Zn, Mn by DTPA-extraction (Lindsay

and Norvell, 1978) .

2. Leaf: After drying_and_wet_ashingj_ determination of

K, Ca, Mg, Fe, Zn, Mn using AAS, P using vanadat-molybdat-

method (Gericke and Kurmies, 1952). Additional in dried

leaves extraction of watersoluble, 0,5 n HC1 and 1 n HC1-

soluble Fe, Zn, Mn (Booss et al., 1982). In fresh material

citratesoluble Fe after Booss et al. (1983).

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1608 BOOSS, HOFNER, AND SCHALLER

1 9 8 0ppm

200 -

100 -

T 2 . 5

inouo

o

6/14 7/1 7/14 7/29 8/12 8/26 Date

ppm HCO«400

300

200

100

Sub soil (20-60cm)

A-.

ppm Pw

35

30

20 -

10

6/14 7/1 7/14 7/29 8/12 8/26 nate

"wso£O

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IRON CHLOROSIS 1609

ppm HCO3

300

200

1 0 0

1981

Subsoil (20-60cm)ppm

35

30

10 -

1.5

1 »

0.5 Jj

6/16 7/1 7/15 7/29 8/13 8/26 Date

Fig. 1

Appraisement of chlorosis and the content of HCO ~ and

water soluble phosphorus in vineyard soil. Mean of ten

rootstocks (1980) resp. eight rootstocks (1981).

The appearance of iron chlorosis was estimated after

visual evaluation by a classification scheme ranging from

0 = green up to 5 = necrotic.

To find out the influence of the different parameters

on the iron chlorosis following mathematical methods were

applied

1. Analysis of variance with multiple range test.

2. Single correlation.

3. Partial correlation.

4. Factor analysis.

5. Stepwise regression.

RESULTS

Total iron content in the soil from the experimental

field ranged between 1,2 and 1,4 %. The DTPA-extraction

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gave in 1980 in both soil layers higher Fe-concentrations

under chlorotic than under green plants. These results

could be reproduced in 1981.

In 1980 the HCO„ -concentration under chlorotic plants

was somewhat higher than under green plants with no dif-

ferences between the two groups in 1981 (Fig. 1). The P -

concentration showed more prominent differences between

green and chlorotic, especially the values in the subsoil

differed significant at every sampling time. This obser-

vation had been proved by the significant positive'corre-

lation between chlorosis appraisement and P -concentration

(Tab. 1).

Regarding the Fe-content in leaves, the very good Fe-

supply of chlorotic leaf blades is obvious. The results

in 1980 of Fe'extraction by 1 n HC1 led only to significant

positive single correlation (r = 0,27+ ) between Fe-con-

tent and appraisement of chlorosis. Further single corre-

lations between chlorosis and the different Fe-extracting

procedures are all non significant.

Calculating the partial correlation for 12 parameters

most closely correlated to the chlorosis appraisement,

gave the following results (Table 2).

It can be demonstrated, that in both years the first

factor characterises the appraisement of chlorosis. The

correlations between chlorosis and soil parameters,espe-

cially in the subsoil, are very close. The relations bet-

ween plant parameters and chlorosis are less distinct.

In 1980 the resistent rootstocks (1 to 6) and the

susceptible ones reached comparable values in the chloro-

sis appraisement. Therefore two separate regression ana-

lyses were run (Fig. 2). For the same reason the rootstocks

no. 1 to 8 and no. 9 to 10 have been grouped together in

1981 (Fig. 3). According to the results shown in Fig. 2

and 3 the Pw~concent of the subsoil is responsible for

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TABLE 1

Significant correlations between appraisement of chlorosis and different soil and plant

parameters during 1980 and 1981 (p = 0,05 %).

ro

s

Topsoil

Fe-DTPA

Zn-DTPA

P

Topsoil

Fe-DTPA

Zn-DTPA

PwpH

Cu-DTPA

1980

0,53+++

0,27++

0,48+++

1981

0,74+++

0,52+++

0,74+++

-0,36*

0,53+++

Subsoil 1980

pH

Fe-DTPA

Cu-DTPA

Zn-DTPA

P

Subsoil 1981

pH

Fe-DTPA

Cu-DTPA

Zn-DTPA

PwSoil moisture

-0,28++

0,61+++

0,73+++

0,44+++

0,87+++

-0,43++

0,73+++

0,94+++

0,53+++

0,94+++

0,57+++

Leaves

Ca

Mg

Fe

Mn

P/Fe

Fe(lnHCl

Leaves

K

Mg

P

Fe

Cu

1980

0,48+++

0,51+++

0,46+++

0,28++

0,56+++

) 0,27++

1981

0,39

0,35+

0,73+++

0,63+++

0,39++

+ = significant at 5 % level

++ = significant at 1 % level

+++ = significant at 0,1 % levelDow

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TABLE 2

Partial correlations between appraisement of chlorosis and

different soil and plant parameters during 1980 and 1981

Subsoil 198O Leaves 1980

Zn-DTPA 0,34++ Fe 0,28++

P w 0,38++

Subsoil 1981 Leaves 1981

Cu-DTPA 0,40+ P 0,47++

P w 0,47++

Tab. 2

Partial correlations between appraisement of chlorosis and

selected independent variables.

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IRON CHLOROSIS 1613

TABLE 3

Factor analysis showing the inherent relations betweenchlorosis and soil resp. plant parameters during 1980an 1981

1980

Factor loadings

Variable

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

PW SCu-DTPA, S

Fe-DTPA, S

Chlorosis

HC03~, S

Soilmoisture, S

Precipitation

Zn-DTPA, S

Zn, T

Fe, W

Mn, T

Fe, T

Chlorosis

Cu-DTPA, S

pw sP, T

Fe, T

Zn-DTPA

Mn-DTPA, S

Zn, T

Soilmoisture

Fe, T

HCO3~, S

Fe (0,5n HC1)

(pattern)

Factor1

0,939

0,928

0,857

0,838

-

0,449

-

-

-

-0,288

-

-

1981

0,975

0,948

0,943

0,731

0,703

0,596

-

0,360

0,558

-

-

-

for principal components

Factor2

-

-

-

-

0,904

0,690

0,889

-

0,522

-0,302

-0,310

-

-

-

-

0,500

0,532

0,413

0,890

0,822

0,692

-

-

-0,541

Factor3

-

-

-

-

-

-

-

0,740

0,738

0,717

-

-

-

-

-

-

-

0,392

-

-

-

0,857

0,603

0,544

Factor4

-

-

-

0,352

-

-0,319

-

-

-

-

0,777

0,757

S = subsoil, T = content in leaves, W = water soluble

in leaves

Tab. 3

Sorted and rotated factor:matrix of selected variables.

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Rootstock 1-8 Rootstock 9-10

i

L= ppm Pw in subsoil

,= soilmoisture

X 1 = ppm P^ in subsoil

X2= Cu-DTPA subsoil

Fig. 2

Influence of different independent variables on the

appraisement of chlorosis at Bechtheim in 1980.

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IRON CHLOROSIS 1615

Rootstock 1-6 Rootstock 7-10

80

^ 70

O 6 0

o

. 50

K 40

•2-30

20

10

A =60.3%

X1= ppm P in subso i lX2= ppm Zn in leaves

7 0

60

50

40

3 0

20

10

-

" /

" /

" / '

- /

1ppm P in subsoil1" " " ~w

X„= ppm Zn in l e a v e s

F ig . 3

Influence of different independent variables on the apprai-

sement of chlorosis at Bechtheim in 1980; HCO ~ is forced

in the regression equation as first one.

appraisement of chlorosis with an amount of 60 %, regard-

less the extent of chlorosis. All other variables did not

exhibit any considerable effect, when considered separately.

By the methods of "stepwise regression" the factor of

influence, determining the appraisement of chlorosis is

found by excluding the influence of all other variables.

Therefore an additional stepwise regression-analysis was

performed, in which the concentration of HCO ~ was forced

as 1. variable in the regression analysis. Here again it

was seen by mathematical evaluation that the HCO "-concen-o

tration of the soil did not have any important impact on

chlorosis. Even in this additional calculation the pre-

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dominant role of the Pw-content was not or only insigni-

ficantly reduced (Fig. 4). Only the DTPA-extractable Cu-

content of the subsoil seems to be involved in producing

chlorosis to a certain extent.

DISCUSSION

The chlorosis of grape-vine-plants in the experimental

field Bechtheim was neither induced by an absolute nor by

a relative Fe-deficiency in the soil.

As could be demonstrated by an analysis of variance

with a subsequent multiple-range-test, no significant dif-

ferences appeared between the Fe-contents of soils and

leaves from the 10 rootstock trials. Therefore the root-

stock trials had not been separated for the mathematical

calculations.

Compared with "green" trials, not only the concen-

trations of DTPA-extractable Fe, but also those of Cu and

Zn in the subsoil reached higher values in chlorotic

trials (Tab. 1). But the high Cu-concentration in the soil,

which had been raised more than the Fe-concentration, did

not lower the Fe-content of chlorotic leaves, excluding

therefore a direct competition between the two metals during

uptake. There is also evidence in the literature (Wallace

et al. , 1976), that concentrations of 1000 ppm Cu or Zn,

applied as sulfate to soils containing CaC0„, did not in-

duce chlorosis in bush beans. This fact is proved in ano-

ther experiment (Amberger et al., 1982) where heavymetals

caused iron chlorosis in a soil with pH 4,9 which was

cured by liming up to pH 5,8 and 6,4. On the other hand

increased Zn-concentration in chlorotic leaves is believed

to have negatively influenced the Fe """-reduction (Olsen

and Brown, 1981).

As can be seen from Fig. 1, the HCO "-concentrationo

in the soil under chlorotic plants reached 1980 only

slightly higher values than under green plants. The slope

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IRON CHLOROSIS 1617

Rootstock 1-6

oo

70

60

50

30

-H 20

10

Rootstock 7-10

oo

80

70

60

50

OS 40

0)

•P^ 20

10

X. = ppm HC0_ in subsoil

X = ppm P in subsoil

Xo = ppm Zn in leaves

Fig. 4

Influence of different independent variables on the apprai-

sement of chlorosis at Bechtheim in 1981.

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of the curve shows a relatively good coincidence between

HCO "-concentration and appraisement of chlorosis. However

it should be mentioned, that the HCO "-concentration inst

soil under green plants at July 1 , exceeded the HCO_ -

concentration under chlorotic at all other sampling times.

In contrary to 1980 no coincidence between appraisement of

chlorosis and HC0_ -concentration in 1981 could be esta-

blished. During this year the Pw~concentration of the soil

corresponded well with the appraisement of chlorosis.

That high concentrations as such don't necessarily

produce chlorosis is to be seen also from a field survey

(Mengel and BUbl, 1983; Schätzel, 1983), in which green

and chlorotic plants in the subsoil. According to Fig. 1

the Pw-concentration within the important soil layer bet-

ween 20 and 60 cm (Steinberg, 1968) reached under chloro-

tic plants values from 100 up to 350 % above these of

the green control. But no positive correlation between

high HCO "-concentration and solubility of P, as postu-

lated by Olsen et al. (1960) could be observed.

In addition to the single and partial correlation the

factor analysis and the stepwise regression analysis had

also proved a positive correlation between the P -concen-

tration of the soil and the appraisement of chlorosis.

Especially the stepwise regression (Fig. 2-4) which eva-

luates the influence of the variables on the appearance

of chlorosis, proved in 1980 a 60 %, in 1981 a 80 % deter-

mination of the appraisement of chlorosis by the P -concen-

tration of the subsoil. The higher influence of P -concen-

tration in 1981 is documented also by the relatively narrow

relation between the slope of P -concentration and severe-

ness of chlorosis (Fig. 1).

The higher HCO "-concentrations in 1980, which leve-

led about 80 ppm above those of 1981 and which were accom-

panied by a more severe chlorosis during 1980, lead to

the suspicion that in spite of all observations mentioned

above, HCO_ is involved also in inducing iron-chlorosis.

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IRON CHLOROSIS 1619

The evaluation of results from other locations proved

the observation, that chlorosis appeared only in cases,

where high concentrations of HCO_ and P were present in

the soil at the same time. Similar results were obtained

by Brown et al. (1959) in experiments with soy-beans and

by Peer (1975) with grapevines. As a further factor of

influence, the weather conditions during the vegetation

period have to be considered (Booss, 1983). They determine

the energy status of the plants decisively and probably

affect the availability of Fe inside the plants (Brown

et al., 1979a and 1979b).

SUMMARY

In a two year field trial on different soil could be

shown that the expression of chlorosis in vineyard is

neither induced through an absoltue Fe-deficiency nor a

relative one. The Fe-content of chlorotic petioles soluble

in H O and citrate buffer is in most cases lower than in

green ones.

With a statistical analysis it could be shown that

there is a great influence of water soluble phosphorus

and HCO ~ in the depth 20 - 60 cm on the appraisement of

chlorosis.

REFERENCES

Amberger, A., R. Gutser and A. Suss. 1982. Iron chlorosis

induced by high copper and manganese supply.

J. Plant Nutr. 5: 715-720

Booss, A.. 1983. Kausalanalytische Untersuchungen zur Chlo-

rose der Weinrebe (Vitis vinifera) auf der Grundlage

von Erhebungsuntersuchungen in Rheinhessen und im

Rheingau.

Dissertation JL-Universität Gießen

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Booss, A., H. Koles£h and W. Höfner. 1982. Chlorose-Ursachen

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Booss, A., H. Kolesch and W. Höfner. 1983. Bestimmung des

"aktiven Eisens" in Pflanzen durch Extraktion mit

Citratpuffer.


Boxma, R. 1972. Bicarbonate as the most ikportant soil

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Brown, J.C. and W.E. Jones. 1975. Phosphorus efficiency as

Agron J. 67: 468-472

Brown, J.C., O.R. Lunt, R.S. Holmes and L.O. Tiffin. 1959.

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chlorosi.

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Brown, J.C., H.M. Cathey, J.H. Bennett and R.W. Thimijan.

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Brown, J.C, C D . Foy, J.H. Bennett and M.N. Christiansen.

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Lindsay, W.L. and W.A. Norvell. 1978. Development of a

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IRON CHLOROSIS 1621

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Documents

A mathematical approach for evaluating iron chlorosis inducing factors