effect of different organic manures/composts on the herbage and essential oil yield of cymbopogon...

Bioresource Technology 92 (2004) 311–319

Effect of different organic manures/composts on the herbageand essential oil yield of Cymbopogon winterianus and theirinfluence on the native AM population in a marginal alfisol

Tanu a, Anil Prakash b, Alok Adholeya a,*

a Centre For Mycorrhizal Research, The Energy Research Institute, Habitat Place, Lodhi Road, New Delhi 110003, Indiab Department of Biotechnology, Barkatullah University, Bhopal, Madhya Pradesh 462026, India

Received 8 March 2003; received in revised form 20 May 2003; accepted 27 June 2003

Abstract

Four organic amendments: leaf compost (LC), vegetable compost (VC), poultry manure (PM) and sewage sludge (SSL) applied

at four doses (40, 80, 100 and 120 t ha�1) were evaluated for their effect on the herbage yield, essential oil content and inoculum

potential (IP) of native arbuscular mycorrhizal fungi (AMF) on three varieties of Java citronella, Cymbopogon winterianus Jowitt

(Manjusha, Mandakini, and Bio-13). PM applied at 100 t ha�1 followed by SSL increased the herbage, essential oil content and dry

matter yield significantly. Bio-13 performed better and produced the highest herbage, essential oil and dry matter yield. The type and

dose of the various organic amendments also significantly influenced the indigenous AMF infectious propagules in soil. Highest

number of AMF propagules were recorded in the LC amended plots in all the three varieties. Amongst the varieties, highest native

mycorrhizal inoculum was recorded in the Bio-13. Least number of AM infectious propagules were recorded in the Mandakini

plants grown in 40 t ha�1 SSL.

� 2003 Elsevier Ltd. All rights reserved.

Keywords: Compost/manures; Cymbopogon sp.; Arbuscular mycorrhizal fungi; Inoculum potential; Herbage yield; Essential oil content

1. Introduction

Indiscriminate use of chemicals and fertilizers has

altered the biological ecosystem, affected non-target

organisms and adversely influenced microorganisms in

the soil. Organic farming, which aims at cultivating theland and raising crops in such a way to keep the soil

alive and in good health may be an alternative to the

present system of farming which solely depends on

chemicals (Dahama, 1996).

Cymbopogon winterianus Jowitt (Java citronella) is an

important essential oil yielding aromatic grass cultivated

in India mainly in the lower hills of Assam, Karnataka

and Southern Gujarat. The steam volatile essential oilsextracted from its leaves are used in perfumery, cosmet-

ics, pharmaceuticals, and flavoring industries (Guenther,

1950; Wealth of India, 1985). Cymbopogon spp. are

known to be very hardy plants that can grow in soil types

*Corresponding author. Fax: +91-11-2468-2144/2145.

E-mail address: [email protected] (A. Adholeya).

0960-8524/$ - see front matter � 2003 Elsevier Ltd. All rights reserved.

doi:10.1016/S0960-8524(03)00198-6

ranging from rich loam to poor laterite but with a pre-

ference to well drained and nutrient rich soils. These

plants are also known for their tolerance to soil salinity

and alkalinity to a higher level than other crops (Kak and

Kaul, 1997). Java citronella is known to respond signi-

ficantly to fertilizers. However, not much information isavailable regarding the cultivation of citronella in mar-

ginal soils amended with composts/manures.

Application of manure compost has a positive effect

on crop production (Woodbury, 1992) wherein the

nutrient deficiencies are correlated to the compost

addition. Improvement in the soil physical structure

after amendment with organic wastes such as municipal

solid waste, sewage sludge, and manure compost hasalso been well documented (Guisquiani et al., 1995;

Wong and Ho, 1991). However, high doses of manure

might be toxic to plants, animals and human beings

(Meek, 1974; Donahue, 1977) and thus, due caution

must be exercised to keep its detrimental effects in check.

The benefits of application of compost manures on crop

production (Wong et al., 1999) and enhanced recovery

of AM population (Gaur and Adholeya, 2000) have

mail to: [email protected]

312 Tanu et al. / Bioresource Technology 92 (2004) 311–319

been reported to be directly related to the rate of applied

dose. The effect of the extent and type of manure com-

posts on native AM inoculum potential applied for en-

hanced crop production has not been investigated under

field conditions where availability of major nutrients

and high P fixation is a limiting factor (Bhatia et al.,

1998) such as in north-western India.

We hypothesized that the plant productivity can beimproved in nutrient deficient soils supplemented with

organic amendments. The present investigation was

therefore designed under field conditions in a nutrient

deficient soil to (i) optimize productivity by varying the

dose and type of compost manures, and its effect on (ii)

the infectivity potential of native arbuscular mycorrhizal

fungi (AMF).

2. Methods

2.1. Experimental design and preparation of field

The field experiment was conducted at The Energy

Research Institute’s field station at Gual Pahari in Hary-

ana state, (77�120E; 280�350N; 255 m above mean sea

level) India. The annual precipitation at this site is 500–

700 mm. The soil was sandy loam hyperthermic typic

Haplutalf (pH 7.38; N 0.012%); NaHCO3 extractable P

2.81 mg kg�1 (Olsen et al., 1954) and exchangeable K 103mgkg�1. The experiment was laid on 24 · 15 m plot,

planted with three varieties of citronella, applied with

four types of compost manure (leaf compost, poultry

manure, vegetable waste and sewage sludge) at four

doses forming various treatments. The treatments were

tested using a split plot completely randomized size in

each block and were replicated three times thereby con-

stituting 48 experimental plots per variety.The site was prepared by repeated ploughing and

planking in order to achieve fine tilth. Various types of

compostmanure combinationswere applied during the field

preparation. Random soil samples were taken from each

bed and analyzed for macro- and microelements (Table 2).

2.2. Planting germplasm and compost manure application

Slips of high yielding varieties of Citronella (C. win-

terianus)-Manjusha, Mandakini and Bio-13 were pro-

Table 1

Chemical characteristics of various composts

Composts pH (1:2.5

soil:H2O)

Electrical

conductivity (dS/m)

Available P

(ppm)

VC 7.60a 6.25 24.20

PM 7.91 8.88 38.50

LC 7.25 9.87 25.35

SSL 7.25 3.60 44.60

VC––vegetable compost; PM––poultry manure; LC––leaf compost; SSL––seaMeans are average of three replicates.

cured from Central Institute of Medicinal and Aromatic

Plants, Experiment Station, Pantnagar, Uttranchal

State, India.

Of the four types of compost used, vegetable compost

and leaf compost was prepared by aerobic decomposi-

tion at TERI’s field station, Gual Pahari. The compo-

sting bin (3 m · 3 m · 1 m) comprising of four units (1.5

m · 1.5 m · 1 m) made of bricks laid in such a mannerthat the walls had gaps for natural aeration. The com-

posts were ready in nine weeks. Poultry litter was pro-

cured from a near by poultry farm and was allowed to

mature for three weeks until the desired C:N ratio was

achieved (Table 1). Sewage sludge with 80% moisture

was procured from the Okhla Sewage Treatment Plant,

Municipal Corporation of Delhi, Government of Delhi,

India and was air-dried. The four doses (40, 80, 100 and120 t ha�1) of each compost manure were mixed thor-

oughly into the soil in each treatment bed before

transplantation. No additional synthetic chemical fer-

tilizer and pesticides were applied during the experiment.

The nutrient profile of the four composts/manures is

given in Table 1.

Slips of all the varieties were transplanted into the

treatment plots at a spacing of 20 cm plant · plant and30 cm row · row.

2.3. Growing conditions and measurements

Standard agronomic practices were followed includ-

ing regular hoeing, weeding (ICAR, 1992). Plants were

irrigated as necessary using overhead sprinklers and

were harvested after 120 days. Samples of the shoot and

soil were drawn from each bed and processed separately.Fresh shoot weight (herbage yield) was recorded and the

sample was then dried and processed for extraction of

essential oil.

The number of infectious propagules of native AMF

in soil core samples drawn from each treatment bed was

determined by infectivity potential (IP) bioassay (Gaur

et al., 1998). One hundred grams of core samples were

put in plastic pots (7 cm height and 5 cm diameter) witheight germinated seeds of Sorghum vulgare. The pots

were kept in a greenhouse (28/22 �C, 68% RH), watered

with deionized water to a moisture content of 60% water

holding capacity and harvested after 14 days. The entire

K

(ppm)

Organic carbon

(%)

Total N

(%)

C:N

557.30 4.33 0.53 8.1

998.20 5.38 0.43 12.5

223.33 6.79 0.51 13.3

261.00 4.45 0.32 13.9

wage sludge.

Table 2

Chemical characteristics of experimental site/trial after the application of various composts

Amendments Dosesa pH (1:2.5) Electrical

conductivity

(dS/m)

Total N (%) Available P

(ppm)

Available K

(ppm)

O:C (%)

VC 1 7.65 0.27 0.024 12.40 105.20 1.23

2 7.65 0.21 0.033 18.86 160.80 1.91

3 7.63 0.31 0.034 22.22 196.60 1.85

4 7.56 0.24 0.035 26.60 210.00 2.20

PM 1 7.43 0.29 0.013 18.40 250.67 1.43

2 7.43 0.23 0.019 24.60 340.01 2.06

3 7.14 0.23 0.025 30.80 390.20 2.06

4 7.36 0.26 0.031 34.62 459.00 2.36

LC 1 7.43 0.36 0.010 10.98 123.30 0.83

2 7.57 0.42 0.015 14.40 256.67 1.64

3 7.57 0.36 0.020 17.60 286.00 1.99

4 7.42 0.48 0.023 23.28 303.66 2.14

SSL 1 7.30 0.80 0.011 13.80 117.20 0.76

2 7.34 0.76 0.019 19.64 140.33 1.60

3 7.38 0.56 0.022 28.09 174.00 1.71

4 7.65 0.70 0.028 32.50 191.30 2.01

VC––vegetable compost; PM––poultry manure; LC––leaf compost; SSL––sewage sludge.a Compost doses 1, 2, 3, and 4 are 40, 60, 100 and 120 t ha�1 respectively. Means are average of three replicates.

Tanu et al. / Bioresource Technology 92 (2004) 311–319 313

root system from each pot was collected, washed and

stained (Phillips and Hayman, 1970) for enumerating

the total number of entry points. The infection units

were finally expressed in IP g soil�1.The phosphorus content was determined by the

method of Kitson and Mellon (1944), after the wet

digestion of the plant samples. Essential oil content in

dried leaves was estimated using Clevenger’s apparatus

(Buggle et al., 1999).

Data were analyzed using analysis of variance (SAS

Institute Inc., 1991). Duncan’s least significant differ-

ences (LSD) was used to separate treatment means whenF -values were significant, using Costat Statistical soft-

ware (Cohort, Berkeley, CA).

3. Results and discussion

3.1. Plant growth and essential oil content

The results of the present study demonstrates the

response of three varieties of Java citronella grown in a

nutrient deficient soil amended with various types and

dose of compost manures. Plant growth in terms ofherbage, essential oil and nutrient uptake was recorded

in the various treatments. The study also reflected the

effect of these organic amendments on the native AM

fungi. Out of the four different organic amendments,

PM applied at 100 t ha�1 was found to be the optimum

dose for maximum herbage yield in all the three varieties

of Java citronella. However, amongst the three varieties,

Bio-13 was found to produce the maximum herbage

yield. Although higher herbage yield was also recorded

in the 120 t ha�1 PM amended soils, the yield was found

to be non-significantly higher. This may imply that the

nutrient requirement of the plants has been fulfilled at100 t ha�1 PM amendment and further increase in the

rate of applied manure was not necessary. Improved

growth in plants has also been reported by Obi and Ebo

(1995), where the authors reported improvement in the

yield of maize when grown in severely degraded sandy

soils that were amended with PM. The present study

also reveals the effect of other types of organic amend-

ments on the growth of Java citronella. Regressionequations (Fig. 1) were developed on the basis of the

relationship between the various compost/manure dose

and herbage yield in the given nutrient deficient soil. The

results revealed that the correlation coefficient of the

Java citronella varieties varied with the type of compost/

manure amendment. Among the three varieties, Bio-13

showed the highest herbage yield (10.57 t ha�1) followed

by Mandakini (10.38 t ha�1) and then Manjusha (10.05t ha�1) at 100 t ha�1 PM application (Fig. 1). The

essential oil content (Figs. 2–4) was also found to follow

the same pattern as observed in herbage yield. Signifi-

cantly higher essential oil content was recorded in the

plants grown in the PM amended plots when compared

to the plants grown in the other organic amendments.

Amongst the varieties, highest essential oil content was

recorded in the Bio-13 variety grown at 100 t ha�1 PM.The response of Java citronella may also be attrib-

uted due to the increased total organic matter, macro-

and micronutrients rendered after the application of

various compost/manure (Table 2). The soil organic

0

6

8

10

12 VC PM LC SSL Regression

0

6

8

10

12

Compost doses (t ha-1)0 20 40 60 80 100 120 140 160

0

6

8

10

12

Manjusha

Mandakini

Bio-13

VC, y* = 5.34 + 0.0369 x**, r2= 0.979 PM, y = 6.05 + 0.0366 x, r2= 0.966LC, y = 5.56 + 0.0301 x, r2= 0.902SSL, y = 5.63 + 0.0385 x, r2= 0.872



Her

bage

yie

ld (t

ha-1

)H

erba

ge y

ield

(t h

a-1)

Fig. 1. Influence of various compost manures and its relationship with herbage yield on three varieties of Cymbopogon winterianus: y� ¼herbage

yield; x�� ¼ compost dose.


matter and macronutrients concentration was found to

increase as the rate of applied organic amendment in-

creased. Similar results have also been reported by

Wong et al. (1999) on amending soils with manure

composts. However, the authors considered single

manure compost while this study involves different types

of organic manures/composts. The authors reportedincreased plant dry weight due to the better nutrient

status of N, P and K in the soils as well as in the plants.

The increased plant yield may also be due to increased

rhizosphere aggregate stability which might have fa-

vored the beneficial microbes which in turn could have

contributed to improved biomass (Caravaca et al.,

2002). In the present study, of all the amendments, PM

at 100 t ha�1 resulted in the maximum herbage yield

as well as higher P uptake in all the three varieties of

citronella.

3.2. Effect of organic amendment on native AM popula-

tions and root colonization

The type of organic amendment had a significant

effect upon the indigenous populations of mycorrhizawith respect to their infectivity potential (IP). Overall,

there was an increase in the native AM population in

soils amended with LC in all the three-citronella varie-

Dry

wei

ght (

g/pl

ant)

0

5

10

15

20

25

Compost dose (t ha-1)

Plan

t P (p

pm)

0

500

1000

1500

2000

2500

LSD (0.05%) Type = 0.39 Dose = 0.46

LSD (0.05%) Type = 50.36 Dose = 69.52

40 80 100 120

0

50

100

150

200

250VC PM LC SSL

LSD (0.05%) Type = 3.99 Dose = 4.01

Oil

yiel

d (

l pl

ant-1

)µ

Fig. 2. Essential oil content, shoot dry weight and P content in plant tissues of Cymbopogon winterianus var. Manjusha influenced due to amendment

of different types of compost manures applied at various doses in an Indian alfisol. The treatment means were separated by two-way ANOVA

through DMRT. LSD––least significant difference (p ¼ 0:05) by DMRT.


ties. This is concurrent to the report by Baby and

Manibhushanrao (1996) where leaf manure amendments

stimulated high arbuscule development and sporulation

in a rice crop. The 40 t ha�1 SSL treated plots did not

show significant increase in AM infective potential for

all varieties when compared to plants grown in other

composts/manures. In general, the infectivity potential

of soils showed a linear increase with increase in dose of

compost manures (Fig. 5). However, the maximum in-

crease in native mycorrhizal population in terms of

infectivity potential was recorded in variety Bio-13 (6.6

IP/100 g soil) in LC plots amended with 120 t ha�1 (Fig.

5). The least IP was recorded in Mandakini (0.6 IP/100 g

soil) at 40 t ha�1 amendment of SSL (Fig. 5). The

0

5

10

15

20

25


0

500

1000

1500

2000

2500

LSD (0.05%) Type = 0.51 Dose = 0.72

LSD (0.05%) Type = 63.87 Dose = 52.19

40 80 100 120

0

50

100

150

200VC PM LC SSL

LSD (0.05%) Type = 4.72 Dose = 6.25

Dry

wei

ght (

g/pl

ant)

Plan

t P (p

pm)

Oil

yiel

d (

l pl

ant-1

)µ

Fig. 3. Essential oil content, shoot dry weight and P content in plant tissues of Cymbopogon winterianus var. Mandakini influenced due to

amendment of different types of compost manures applied at various doses in an Indian alfisol. The treatment means were separated by two-way

ANOVA through DMRT. LSD––least significant difference (p ¼ 0:05) by DMRT.


variation in the IP amongst the varieties as observed in

this study indicates host dependency and can be ex-

plained on the basis of numerous reports (Bever et al.,

1996; Daft and Hogarth, 1983; Hetrick and Bloom, 1986;Hung and Sylvia, 1988; Koomen et al., 1987) where the

authors described that the sporulation rates of AM fungi

were found to be host dependent under laboratory sys-

tems. There are also a number of reports on the effect of

organic amendment application on indigenous VAM

populations. Douds et al. (1997) reported an increase in

AM fungi spore populations of certain AM species in

soils receiving organic amendments in the form of

chicken litter/LC in comparison to those soils receivingraw diary manure and conventional fertilizers (M€aderet al., 2000). Verma and Arya (1998) reported an

enhancement of AM spore production by several times

in bamboo rhizosphere amended with organic manure.

The enhancement of the spore production in organic

0

500

1000

1500

2000

2500


0

500

1000

1500

2000

2500

LSD (0.05%) Type = 0.68 Dose = 0.54

LSD (0.05%) Type = 31.64 Dose = 45.45

40 80 100 120

0

50

100

150

200

250 VC PM LC SSL

LSD (0.05%) Type = 6.13 Dose = 5.98

Dry

wei

ght (

g/pl

ant)

Plan

t P (p

pm)

Oil

yiel

d (

l pl

ant-1

)µ

Fig. 4. Essential oil content, shoot dry weight and P content in plant tissues of Cymbopogon winterianus var. Bio-13 influenced due to amendment of

different types of compost manures applied at various doses in an Indian alfisol. The treatment means were separated by two-way ANOVA through

DMRT. LSD––least significant difference (p ¼ 0:05) by DMRT.


manure amended medium may be due to enhanced

growth and spread of AM hyphae as reported by Hep-

per and Warner (1983), Joner and Jakobson (1992) and

St John et al. (1983). Muthukumar and Udaiyan (2002)

while working on mycorrhizal response of cowpea under

organic farming reported higher mycorrhizal production

in plants grown in soils amended with organic manure

than in the non-amended soils. They also reported thatthe mycorrhizal response highly correlated with the type

of organic manure. They also suggested that the growth

and yield of cowpea in response to organic amendment

was a result of the differential effects of the types of

amendment on the production of different AM fungi

within the community.

The lower IP of the native AM fungi in SSL and PM

amendments could be due to the high available P in

these soils. PM is known to increase the availability of Pin soils (Toor and Bahl, 1997) and hence a negative effect

No.

of i

nfec

tious

pro

pagu

les

(per

100

g s

oil)

0

1

2

3

4

5

6 ManjushaMandakiniBio-13

0

1

2

3

4

5

6

7

0

1

2

3

4

5

6

7

8


40 80 100 120 0

1

2

3

4

5

6

7

Vegetable compostLSD (0.05) Variety = 0.91 Compost dose = 1.25

Poultry manureLSD (0.05) Variety = 1.33 Compost dose = 1.03

Leaf compostLSD (0.05) Variety = 1.58 Compost dose = 1.48

Sewage sludgeLSD (0.05) Variety = 0.99 Compost dose = 1.27

No.

of i

nfec

tious

pro

pagu

les

(per

100

g s

oil)

Fig. 5. Effect of compost manure upon the native AM population in

the rhizosphere of three varieties of Cymbopogon winterianus.


on the native AM populations and enhanced herbage

yield and P uptake was observed in plants grown in this.

Higher soil P availability is known to suppress VAM

fungal colonization (Ryan and Ash, 1999; Sharma andAdholeya, 2001; Valentine et al., 2001) and spore den-

sity (Menge et al., 1978).

While comparing the nutrient profile of the experi-

mental site with the ratings of medium fertility levels

(Singh et al., 1999), the site was deficient in essential

major nutrients. The compost manure application at the

rate of 40 t ha�1 in the soil supplied these nutrients to

levels observed in medium fertility soils but the maxi-

mum response in terms of herbage yield has been

exhibited at the 100 t ha�1 PM amendment thus imply-ing the high levels of organic amendments required

(Table 2).

The regression equation models developed in the

present study can be used to assess the rate of compost/

manure amendment required to achieve the desired

herbage yield for citronella growers of a region. The

results of this study also strongly suggest the possibility

of obtaining increased citronella production under or-ganic agriculture by applying appropriate combinations

of organic amendments.

Acknowledgements

The present study was supported by funding from the

Department of Biotechnology, Government of India toAA. The authors wish to thank the Director General,

Dr. R.K. Pachauri, The Energy Research Institute for

providing the infrastructure facilities. The authors wish

to thank Dr. Mahaveer P. Sharma for providing intel-

ligent inputs during designing of experiment and statis-

tical advice. The authors also wish to acknowledge

Mr. U. Gangi Reddy for his help in the soil and plant

analysis. The technical assistance of Mr. SailendraKumar in conducting the experiment and subsequent

analysis work is duly acknowledged.

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effect of different organic manures/composts on the herbage and essential oil yield of cymbopogon...

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