53

B.L. Rao, Vikas Mehra, M.K. Bhan and A.K. DharJ. Trop. Agric. and Fd. Sc. 36(1)(2008): 53– 59

Natural variation and correlation studies of morphological traits in a population of Curcuma amada Roxb.(Kajian pembezaan dan korelasi ciri morfologi populasi Curcuma amada Roxb.)

B.L. Rao*, Vikas Mehra*, M.K. Bhan* and A.K. Dhar*

Key words: mango ginger, Curcuma amada, morphological traits, simple, partial and multiple correlations

AbstractCurcuma amada Roxb., commonly known as mango ginger, is used in folklore medicine, culinary preparation, and for the production of oleoresin and essential oil. In the ayurvedic and unani systems of medicine, the rhizome (the underground part) is used as an antifungal, anti-inflammatory and antihyperglyceridemic agent. All the characters under study showed wide variations. The highest coefficients of variation (CV) were recorded for herb yield (69.0%), corm weight (58.8%) and finger weight (55.7%) while the lowest were for finger length (26.4%), leaf length (26.5%) and sheath length (26.8%). Finger weight had significant and positive correlations with all the other characters except sheath length. The highest correlation was recorded with corm weight (r = 0.772), while partial and multiple correlations suggest that corm weight, herb yield and finger length are important components for increasing finger weight. Essential oil after Thin Layer Chromatography (TLC), Gas Liquid Chromatography (GLC) and 1HNMR analyses showed β-myrcene to be the major compound with a mean value of 39.68 ± 8.03.

*Plant Breeding and Crop Husbandry Division, Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu Tawi 180001, (India)Authors’ full names: Rao B.L., Vikas Mehra, Bhan M.K. and Dhar A.K.E-mail: arunalakshmi@rediffmail.com©Malaysian Agricultural Research and Development Institute 2008

IntroductionCurcuma amada, a rhizomatic herb commonly known as mango ginger (amba haldi), belongs to the genus Curcuma L, family Zingiberaceae, and tribe Hedychieae. The genus Curcuma comprises about 70 species with a distribution spreading from India to Thailand, Malaysia, Indonesia, China and Australia. In India, C. amada grows wild in different parts of India. Recently, this species was introduced and domesticated under Jammu (North Indian Plains) conditions (Rao et al. 2005). Rhizomes of the species are buff coloured outside with a light yellow or white inner

epidermal layer, and are used in folklore medicines, in culinary preparations such as preserves, candy, pickles and sauce, and for the manufacture of oleoresin, essential oil, etc. (Gupta 2001). Other than in folklore medicines, the rhizomes are also used in ayurvedic and unani systems of medicines since they possess antifungal, antiinflammatory, anticancer and antihyperglyceridemic properties (Ghosh et al. 1980; Srinavasan and Chandershekhara 1992; Majumdar et al. 2000; Gupta 2003; Rao et al. 2005). Chemically, rhizome oil of C. amada is reported to be a rich source of β-myrcene

54

Correlation studies of morphological traits in of Curcuma amada

along with some other minor compounds (Choudhary et al. 1996; Gupta 2003; Singh et al. 2003). In some areas, this species is cultivated for its beautiful yellow flowers arranged in dense compound green spikes crowned by a coma of pink enlarged bracts, produced directly from the rootstock at the base of the plant (Plates 1–3). Recently, indigenous accessions of C. amada were introduced to this laboratory and evaluated for ecological suitability, plant structure, adaptability and yield potential (Rao et al. 2005). Correlation provides a measure of association between different variables and helps to formulate selection indices. In view of its importance in perfumery and pharmaceutical industries, efforts were made to assess the existing variability within the species through simple statistics, i.e. range, mean, coefficient of variation and correlation studies as no such study has been done so far.

Materials and methodsA total of 100 plants were selected at random from a C. amada population (collected in Andhra Pradesh, Maharashtra and Orissa from wild habitats, private nurseries and organizations) and grown under uniform cultural conditions at the Indian Institute of Integrative Medicine Farm, Jammu during 2002–2004. The method of planting and cultural practices was the same as reported by Rao et al. (2005). Jammu, a subtropical region of the northern part of India, is situated at 32° 44’ N latitude, 74° 55’E longitude, and 400 m above sea level, with temperatures ranging from 5.50–45 °C and a total annual rainfall of 506 mm. Plants of uniform age (one year) were taken, and observations were recorded on sheath length, plant height, leaf length, finger weight, finger length, corm weight and herb (leaf) yield. The soil of the crop was sandy loam in texture, with a pH of 6.8, 0.27% organic carbon, and medium in available phosphorous and potash (14 kg and 136 kg/

ha, respectively). Decomposed farm yard manure at 20 t/ha was applied before preparation of the field for planting. In addition, a basal dose of 50 kg/ha P

2O

5

(single superphosphate), 20 kg/ha K2O

(muriate of potash), 15 kg/ha N was applied at 45 days, and remaining 15 kg/ha N was top dressed at 75 days after planting. Plant-to-plant and row-to-row distances were maintained at 0.4 m x 0.4 m. Mean, range, standard error and coefficient of variation of all the parameters were analysed statistically, and also simple, partial and multiple correlations were worked out by SPSS software. Fresh rhizomes were distilled in Clevenger’s apparatus (Clevenger 1928) to obtain essential oil. Thin layer chromatography (TLC), gas liquid chromatography (GLC) and proton nuclear magnetic resonance (1HNMR) were used to identify, measure and confirm the major compounds in the essential oil.

Results and discussionAll the characters under study showed wide variations. Rhizome, the main commercial part of the plant, is the underground portion comprises tubers (root system), corm and fingers (stem system) (Plate 4). The highest coefficients of variation (CV) were recorded for herb yield (69.0%), corm weight (58.8%) and finger weight (55.7%), while the lowest were for finger length (26.4%), leaf length (26.5%) sheath length (26.8%) and plant height (26.8%) (Table 1). Essential oil obtained after hydro-distillation using Clevenger’s apparatus was subjected to TLC, GLC and 1HNMR analyses. β-myrcene was the major compound with varying concentration. Its concentration ranged from 7.2–92.5% with a mean value of 39.68 ± 8.03 and 78.37% coefficient of variation. Oil concentrations of some selected types along with percentages of β-myrcene are given in Table 2. Positive and significant correlations were observed between corm weight and finger weight with the maximum

55

B.L. Rao, Vikas Mehra, M.K. Bhan and A.K. Dhar

Plate 3. Close-up of Curcuma amada flower

Plate 1. Field view of Curcuma amada crop Plate 2. Flowering in Curcuma amada

number of characters except sheath length (Table 3). Similarly, positive and significant correlations were recorded between herb yield and leaf length, plant height and finger length. Highest positive and significant correlation was recorded between plant height and leaf length (r = 0.858), followed by corm weight with herb yield (r = 0.839)

indicating that longer leaf length, taller plant height and herb yield enhance finger weight and corm weight. Significant and positive correlations were recorded between finger weight and corm weight when the other characters were kept constant singly or in combination, the highest being 0.769, 0.750, 0.738, 0.713

Table 1. Morphological and yield attributes of Curcuma amada

Range Mean ± S.E CV (%)

Finger weight 85–660 g 299.7 ± 18.63 g 55.7Corm weight 15–360 g 139.98 ± 9.85 g 58.8Herb yield 50–380 g 98.36 ± 8.10 g 69.0Finger length 4–11 cm 7.62 ± 0.24 cm 26.4Plant height 26–103 cm 72.46 ± 2.48 cm 26.8Sheath length 2–14 cm 5.97 ± 0.32 cm 26.8Leaf length 15–54 cm 35.21 ± 1.12 cm 26.5

Plate 4. (a) Tubers (b) fingers and (c) corms of Curcuma amada after harvest

a b c

56

Correlation studies of morphological traits in of Curcuma amada

Table 2. Oil concentration and β–myrcene content in different selections of Curcuma amada

Plant Oil (%, β-myrceneno. fresh wt. basis) (%)

1 0.43 92.5 2 0.34 82.8 3 0.20 20.8 4 0.25 32.5 5 0.19 24.6 6 0.21 70.5 7 0.30 60.6 8 0.24 75.5 9 0.40 66.310 0.26 7.211 0.30 10.312 0.20 15.513 0.31 20.314 0.10 08.515 0.15 07.5

Mean 0.258 39.68S.E. 0.023 8.03C.V. (%) 34.78 78.37

Table 3. Simple correlation coefficients among various morphological traits in Curcuma amada

Character Corm Herb Sheath Leaf Plant Finger weight yield length length height length (g) (g) (cm) (cm) (cm) (cm)

Finger weight (g) 0.772** 0.715** 0.122 0.289* 0.370** 0.472**Corm weight (g) 0.839** 0.120 0.313** 0.349** 0.437**Herb yield (g) –0.015 0.248* 0.301* 0.336**Sheath length (cm) 0.300* 0.338** 0.194Leaf length (cm) 0.858** –0.069Plant height (cm) –0.064

**p <0.01; *p <0.05

when sheath length, leaf length and plant height was kept constant singly. Similarly, significant and positive correlations were recorded between finger weight and finger length when other characters were kept constant singly or in combination, highest being 0.535 and 0.575 when plant height, leaf length were kept constant singly, and 0.550 when sheath length, leaf length and plant height were kept constant in combination (Table 4). There was no significant correlation between finger weight and sheath length singly or in combination with other characters. When three or more characters were kept constant,

non-significant negative correlations were recorded between finger weight, leaf length and sheath length. Multiple correlation coefficients for a combination of variables (Table 5) indicated that in combination, the relative contribution was not very high. With the combination of two independent variables, the contribution of corm weight, leaf length and finger length was 63.04%, 61.78% followed by 61.15% by corm weight and herb yield. With the combination of three independent variables, the relative contribution ranged from 53.43–62.57%, the highest being corm weight, leaf length and finger weight (62.57%). When leaf length was replaced by herb yield, the contribution was 62.41%. With the combination of four or five characters, the relative contribution varied from 39.94–64.80%, the highest being with corm weight, sheath length, leaf length, plant height and finger length (64.80%) and when finger length was replaced by herb yield the contribution was 62.72%. In a selection programme, a combination of two to three characters at a time is considered more useful than a combination of four or five characters. Thus, among the traits investigated, corm weight, herb yield and finger length appeared to be important components for increasing finger weight.

ConclusionCurcuma amada grows very well in Jammu/north Indian plains, and is adapted to the subtropical conditions. Corm weight,

57

B.L. Rao, Vikas Mehra, M.K. Bhan and A.K. Dhar

Tabl

e 4.

Sim

ple

and

part

ial

corr

elat

ion

coef

ficie

nts

(r)

amon

g va

riou

s m

orph

olog

ical

tra

its i

n C

urcu

ma

amad

a

Fing

er

Cor

m

H

erb

Sh

eath

Lea

f

Plan

t

Fing

erw

eigh

t (1

) w

eigh

t (2

)

yiel

d(3)

leng

th (

4)

le

ngth

(5)

heig

ht (

6)

le

ngth

(7)

r12

0.77

2**

r13

0.71

5**

r14

0.12

2 r1

5 0.

289*

r1

6 0.

370*

* r1

7 0.

472*

*r1

2.3

0.45

3**

r13.

2 0.

195

r14.

2 0.

047

r15.

2 0.

078

r16.

2 0.

169

r17.

2 0.

235*

r12.

4 0.

769*

* r1

3.4

0.72

2**

r14.

3 0.

190

r15.

3 0.

165

r16.

3 0.

233*

r1

7.3

0.35

2r1

2.5

0.75

0**

r13.

5 0.

694*

* r1

4.5

0.03

8 r1

5.4

0.26

6*

r16.

4 0.

352*

* r1

7.4

0.46

0**

r12.

6 0.

738*

* r1

3.6

0.68

1**

r14.

6 –0

.004

r1

5.6

-0.0

61

r16.

5 0.

249*

r1

7.5

0.51

5**

r12.

7 0.

713*

* r1

3.7

0.67

0**

r14.

7 0.

035

r15.

7 0.

365*

* r1

6.7

0.45

5**

r17.

6 0.

535*

*r1

2.34

0.

427*

* r1

3.24

0.

210*

r1

4.23

0.

092

r15.

23

0.08

5 r1

6.23

0.

169

r17.

23

0.25

2*r1

2.35

0.

435*

* r1

3.25

0.

198

r14.

25

0.02

6 r1

5.24

0.

067

r16.

24

0.16

3 r1

7.24

0.

231*

r12.

36

0.42

9**

r13.

26

0.19

4 r1

4.26

–0

.008

r1

5.26

–0

.121

r1

6.25

0.

193

r17.

25

0.26

2*r1

2.37

0.

388*

* r1

3.27

0.

216*

r1

4.27

0.

010

r15.

27

0.14

2 r1

6.27

0.

244*

r1

7.26

0.

292*

*r1

2.34

5 0.

419*

* r1

3.24

5 0.

208*

r1

4.23

5 0.

071

r15.

234

0.06

2 r1

6.23

4 0.

140

r17.

234

0.24

2*r1

2.34

6 0.

417*

* r1

3.24

6 0.

199

r14.

236

0.03

9 r1

5.23

6 –0

.108

r1

6.23

5 0.

182

r17.

235

0.28

3*r1

2.34

7 0.

374*

* r1

3.24

7 02

23*

r14.

237

0.05

7 r1

5.23

7 0.

156

r16.

237

0.25

0*

r17.

236

0.31

1**

r12.

356

0.43

6**

r13.

256

0.18

8 r1

4.25

6 –0

.005

r1

5.24

6 –0

.121

r1

6.24

5 0.

191

r17.

245

0.26

4*r1

2.35

7 0.

346*

* r1

3.25

7 0.

225*

r1

4.25

7 –0

.040

r1

5.24

7 0.

148

r16.

247

0.26

0*

r17.

246

0.30

5**

r12.

367

0.39

4**

r13.

267

0.22

3*

r14.

267

–0.0

92

r15.

267

–0.1

12

r16.

257

0.22

9*

r17.

256

0.28

9**

r12.

456

0.74

2**

r13.

456

0.68

7**

r14.

356

0.11

8 r1

5.34

6 –0

.066

r1

6.34

5 0.

155

r17.

345

0.36

7**

r12.

457

0.66

4**

r13.

457

0.63

0**

r14.

357

0.04

2 r1

5.34

7 0.

213*

r1

6.34

7 0.

300*

* r1

7.34

6 0.

399*

*r1

2.56

7 0.

651*

* r1

3.56

7 0.

615*

* r1

4.56

7 –0

.150

r1

5.46

7 –0

.051

r1

6.45

7 0.

318*

* r1

7.45

6 0.

550*

*r1

2.34

56

0.42

4**

r13.

2456

0.

191

r14.

2356

0.

006

r15.

2346

–0

.109

r1

6.23

45

0.17

2 r1

7.23

45

0.27

4*r1

2.34

57

0.34

4**

r13.

2456

7 0.

222*

r1

4.23

57

0.00

6 r1

5.23

47

0.14

6 r1

6.23

47

0.24

8*

r17.

2346

0.

311*

r12.

3456

7 0.

344*

* r1

3.24

567

0.20

2 r1

4.23

567

–0.0

43

r15.

2346

7 –0

.096

r1

6.23

457

0.22

4*

r17.

2345

6 0.

308*

*

**p

<0.

05

*p <

0.01

Not

e: r

12 i

s th

e co

rrel

atio

n be

twee

n fin

ger

wei

ght

and

corm

wei

ght

whi

le r

12.3

is

the

corr

elat

ion

betw

een

finge

r w

eigh

t an

d co

rm w

eigh

t w

hen

the

char

acte

r 3

(i.e

. her

b yi

eld)

was

kep

t co

nsta

nt. I

n st

atis

tical

ter

ms

it is

a p

artia

l co

rrel

atio

n. r

12.3

456

7 is

the

cor

rela

tion

coef

ficie

nt b

etw

een

finge

r w

eigh

t an

d co

rm w

eigh

t w

hen

the

othe

r fiv

e va

riab

les

are

kept

con

stan

t

58

Correlation studies of morphological traits in of Curcuma amada

Table 5. Multiple correlation coefficients among the morphological traits in Curcuma amada

% Contribution

R1 (23) 0.782 61.15R1 (24) 0.773 59.75R1 (25) 0.794 63.04R1 (26) 0.780 60.84R1 (27) 0.786 61.78R1 (34) 0.727 52.28R1 (35) 0.724 52.41R1 (36) 0.733 53.72R1 (37) 0.756 57.15R1 (45) 0.291 8.46R1 (46) 0.370 13.69R1 (47) 0.473 22.37R1 (56) 0.375 14.06R1 (57) 0.571 32.60R1 (67) 0.619 38.31R1 (234) 0.784 61.46R1 (235) 0.784 61.46R1 (236) 0.789 62.25R1 (237) 0.798 62.41R1 (245) 0.774 59.90R1 (246) 0.778 60.53R1 (247) 0.786 61.78R1 (256) 0.783 61.31R1 (257) 0.791 62.57R1 (345) 0.731 53.43R1 (346) 0.737 54.31R1 (347) 0.761 57.91R1 (356) 0.734 53.87R1 (357) 0.772 59.59R1 (2345) 0.785 61.62R1 (2346) 0.789 62.25R1 (2347) 0.798 60.84R1 (3456) 0.739 54.61R1 (3457) 0.773 59.75R1 (4567) 0.632 39.94R1 (23456) 0.792 62.72R1 (23457) 0.803 64.48R1 (24567) 0.805 64.80R1 (34567) 0.786 61.78

1. Finger weight 2. Corm weight 3. Herb yield4. Sheath length 5. Leaf length 6. Plant height 7. Finger length

herb yield and finger length are important components for increasing finger weight.

AcknowledgementThe authors are thankful to the National Medicinal Plants Board, New Delhi for financial help, and to the Director of the Indian Institute of Integrative Medicine, Jammu for providing facilities to carry out these studies.

ReferencesChoudhary, S.N., Rabha, L.C., Kanjilal, P.B.,

Ghosh, A.C. and Laclercq, P.A. (1996). Essential oil of Curcuma amada Roxb. from Northeastern India. J. Essent. Oil Res. 8: 79–80

Clevenger, J.F. (1928). Apparatus for determination of volatile oils. Amer. Pharm. Assoc. 17: 345–349

Ghosh, S.B., Gupta, S. and Chandra, A.K. (1980). Antifungal activity in rhizomes of Curcuma amada Roxb. Indian J. Exp. Biol. 18: 174–176

Gupta, A.K. (2003). Quality standards of Indian medicinal plants, Vol.1. p. 82–88. New Delhi: Indian Council of Medical Research

Gupta, V.K. (2001). The wealth of India: First supplemented series (Raw materials), Vol. 2. p. 259–260. New Delhi: Council of ScientificNew Delhi: Council of Scientific and Industrial Research, Pusa

Majumdar, A.M., Naik, D.G., Dandge, C.N. and Puntambeker, H.M. (2000). Anti-inflammatoryAnti-inflammatory activity of Curcuma amada Roxb. in albino rats. Ind. J. of Pharmacology 32(6): 375–377

Rao, B.L., Dhar, A.K., Taneja, S.C. and Mehra, V. (2005). β-myrcene rich Curcuma amada Roxb.– A new introduction for Jammu/north Indian plains. Paper presented in 1st Jammu & Kashmir State Science Congress, 7–9 Feb. 2005, University of Jammu, p. 36

Singh, G., Prakash, O., Lampasona, M. P. and Catalan, C. (2003). Curcuma amada Roxb. chemical composition of rhizome oil. Indian Perfumer 47(2): 143–146

Srinavasan, M.R. and Chandershekhara, N. (1992). Effect of mango ginger (Curcuma amada Roxb.) on the lipid status in normal and hypertriglyceridemic rats. J. Food Sci. Tech. 29: 130 –132

59

B.L. Rao, Vikas Mehra, M.K. Bhan and A.K. Dhar

AbstrakCurcuma amada Roxb., dengan nama tempatan ‘mango ginger’, digunakan sebagai ubatan tradisional, bahan masakan dan untuk pengeluaran oleoresin dan minyak pati. Dalam sistem perubatan ayurvedia dan unani, rizom (bahagian bawah tanah) digunakan sebagai antikulat, antikeradangan dan agen antihipergliseridemik. Semua ciri yang dikaji menunjukkan perbezaan yang luas. Variasi koefisien yang tertinggi dicatatkan pada hasil herba (69.0%), berat umbisi (58.8%) dan berat ‘finger’ (55.7%), manakala yang terendah ialah panjang ‘finger’ (26.4%), panjang daun (26.5%) dan panjang ‘sheath’ (26.8%). Berat ‘finger’ mempunyai korelasi signifikan dan positif dengan parameter lain kecuali panjang ‘sheath’. Korelasi tertinggi dicatatkan pada berat umbisi (r = 0.772), manakala korelasi separa dan berganda menunjukkan berat umbisi, hasil herba dan panjang ‘finger’ ialah komponen penting untuk meningkatkan berat ‘finger’. Minyak pati yang dianalisis menggunakan TLC, GLC dan 1HNMR menunjukkan β-myrcene ialah sebatian utama dengan nilai purata 39.68 ± 8.03.

Accepted for publication on 25 September 2007