Influence of different dates of planting on growth, herb ...

Archives of Agronomy and Soil Science

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Influence of different dates of planting on growth, herb, oil yield and quality of essential oil of menthol mint (Mentha arvensis) in the North Indian Plain Rajesh K. Chauhan , Mohammed Anwar , Sukhmal Chand & Dharani D. Patra To cite this article: Rajesh K. Chauhan , Mohammed Anwar , Sukhmal Chand & Dharani D. Patra (2012) Influence of different dates of planting on growth, herb, oil yield and quality of essential oil of menthol mint (Mentha arvensis) in the North Indian Plain, Archives of Agronomy and Soil Science, 58:2, 223-232, DOI: 10.1080/03650340.2010.507354 To link to this article: https://doi.org/10.1080/03650340.2010.507354

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Archives of Agronomy and Soil Science Vol. 58, No. 2, February 2012, 223–232

Influence of different dates of planting on growth, herb, oil yield and quality of essential oil of menthol mint (Mentha arvensis) in the North Indian Plain Rajesh K. Chauhana*, Mohammed Anwara, Sukhmal Chanda and Dharani D. Patrab a

Agrotechnology, Central Institute of Medicinal and Aromatic Plants, Lucknow, India; bSoil Science, Central Institute of Medicinal and Aromatic Plants, Lucknow, India (Received 18 September 2009; final version received 2 July 2010) A field experiment was conducted for two years (2007–2008 and 2008–2009) to study the effect of different dates of planting for three menthol mint (Mentha arvensis) cultivars (Saksham, Kushal and Kosi; developed by Central Institute of Medicinal and Aromatic Plants, Lucknow, India) on herb yield, oil yield and oil quality. All the cultivars produced higher herb and oil yields when planted on 18 February, compared with cultivars planted on other dates in both years. Average herb yield for Saksham increased by 12.89, 30.66, 54.01 and 85.71%, average herb yield for Kushal increased by 15.09, 30.57, 71.69 and 104.91%, and average herb yield for Kosi increased by 32.48, 53.28, 87.23 and 109.49% when planted on 4 January, 19 January, 3 February and 18 February, respectively, over cultivars planted on 20 December. Among the cultivars, Kosi produced a higher herb yield than Saksham and Kushal planted on 18 February. Saksham, Kushal and Kosi produced *89.39, 152.04 and 170.22% higher oil yield, when planted on 18 February over their respective planting date of 20 December. Maximum menthol content was recorded in cultivar Saksham when planted on 18 February and in Kushal and Kosi when planted on 4 March. Keywords: menthol mint; Kosi; Saksham; Kushal; essential oil; menthol

Introduction Menthol mint (Mentha arvensis) is a potential source of natural menthol and dementholized oil, and is cultivated in the tropics and subtropical countries worldwide. The area under menthol mint cultivation in India is estimated to be 0.15 million ha, with annual production of 20,000 t of essential oil. The crop is commercially cultivated in tarai and the central part of Uttar Pradesh (Barabanki, Raebareli, Rampur, Bareli, Badaun, Moradabad, Amroha, Rudrapur Bilaspur), Punjab, Bihar and Haryana (Singh et al. 1998). On hydro-distillation, the plant yields essential oil containing *70–80% menthol, which is used in various pharmaceutical, food and cosmetic preparations. Besides China and the USA, India is a major producer of mint oil which is mostly exported to the USA and European countries. There are possibilities for

*Corresponding author. Email: cool_rajesh30@rediffmail.com ISSN 0365-0340 print/ISSN 1476-3567 online Ó 2012 Taylor & Francis http://dx.doi.org/10.1080/03650340.2010.507354 http://www.tandfonline.com

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further increasing the production of mint oil in India by adopting new, improved agro technologies. Currently, the Central Institute of Medicinal and Aromatic Plants (CIMAP) is engaged in developing new high-yielding cultivars of menthol mint, which can acclimatize to the changing environment (temperature, rainfall, day length and sunshine) and give a superior quality of essential oil. Among the various agronomic factors, optimum planting time determines herb yield and superior quality essential oil production in most of the essential-oil-bearing crops. Earlier studies have revealed that the optimum planting time is mid January for the tarai region of Uttar Pradesh and Uttranchal (Singh and Nand 1979) and the eastern Gangetic plain of West Bengal (Ghosh and Chatterjee 1978), and first week of March for the temperate climate of Himachal Pradesh (Katoch et al. 1979). With fluctuations in environmental parameters (temperature, change in rainfall distribution and increasing CO2 concentrations) it has become imperative to evaluate the most appropriate time of planting for maximum productivity and superior quality of oil. The objective of this study was to determine the optimum planting date for menthol mint in the Central Gangetic alluvial plains of India. Materials and methods A field experiment was conducted at the same site for two years (2007–2008 and 2008–2009) at the research farm of CIMAP, Lucknow, India, located at 26.58 N and 85.58 E and at 120 m above mean sea level. The mean monthly minimum temperature varied from 8.968C in December to 26.748C in June and the maximum temperature ranged between 26.258C in December and 32.518C in June, relative humidity ranged from 39.66 to 76.95% (min) in December to 68.28 to 84.96% (max) in June (Table 1). Soil samples were collected from each plot and shade-dried and sieved (52 mm). Samples were analyzed for different soil characteristics using standard methods (Walkley and Black 1934; Page et al. 1992). The soil pH was 8.15, the texture was sandy loam by the hydrometer method, organic carbon was 0.55% (Walkley and Black 1934), available nitrogen was 170 kg ha71 by the Kjeldahl method, exchangeable potassium was 436 kg ha71 by a flame photometer and the available phosphorus was 93 kg ha71 by UV spectrophotometer method. Except for soil organic carbon, all methods are as described by Page et al. (1992). The treatment combinations comprised six planting dates (20 December, 4 January, 19 January, 3 February, 18 February and 4 March, in 2007–2008 and 2008–2009) and three cultivars of menthol mint (Saksham, Kushal and Kosi), which were evaluated in a factorial randomized block design with three replications. Growth and yield parameters were recorded at maturity and at flower initiation (108–110 days) in all cultivars in both years and cultivars were harvested by hand at the same number of days after planting. In both years, fresh and healthy suckers (0.5 t ha71) of each cultivar were planted in rows 45 cm apart. Suckers were covered by adjacent soil immediately after placement in furrows to avoid loss of moisture and this was followed by flood irrigation. Nitrogen, phosphorus and potassium were applied at the rate of 200:40:40 kg ha71 through urea, single super phosphate and muriate of potash, respectively. Half the nitrogen was applied at planting and a full dose of phosphorus and potassium were applied as pre-plant in each treatment. The remaining nitrogen

Min

8.96 8.15 9.92 17.55 20.93 24.41 26.25

December January February March April May June

23.74 22.44 24.62 32.58 37.75 37.01 32.51

Max

2007–2008

9.13 7.93 10.08 17.11 21.71 23.59 26.14

Min 24.85 22.92 24.38 33.19 36.69 37.51 35.26

Max

2008–2009

Temperature (8C)

39.66 42.24 40.20 33.79 32.40 34.09 68.28

Min 76.95 79.74 73.13 64.55 45.42 56.04 84.96

Max

2007–2008

40.61 41.81 40.67 33.93 44.26 32.28 52.82

Min 77.49 79.53 74.83 66.37 66.01 64.99 79.24

Max

2008–2009

Relative humidity (%)

Average monthly metrological data during both years of the experiment.

Months

Table 1.

6.17 4.26 7.08 5.99 8.63 7.34 3.82

2007–2008

6.26 4.16 6.82 6.56 8.45 7.42 4.45

2008–2009

Sunshine (h)

63.6 152.0

2007–2008

15.9 71.25

2008–2009

Rainfall (mm)

Archives of Agronomy and Soil Science 225

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was applied 30 and 60 days after planting of suckers. The crop was irrigated at weekly intervals in April, May and June, and at a 2–3-week interval in December, January and February when needed. Manual weeding was carried out two to three times to keep the field weed free, especially at the beginning of crop establishment. To estimate oil content, 100 g of a composite sample of fresh herb under each treatment and replication was distilled in Clevenger’s type apparatus (Clevenger 1928). The chemical composition of the essential oil for quality evaluation was analyzed on a Perkin–Elmer GC model Auto XL with FID and capillary column PE (50 m 6 0.32 mm i.d., 0.25 mm film thickness) using a temperature program from 100 to 2808C and H2 as carrier gas at 10 psi inlet pressure (Perkin–Elmer Inc., Shelton, USA). Injector and detector temperatures of 220 and 2908C, respectively, were applied in the analyses. Turbochrom software was used for peak percentage calculation. Identification of oil components was based on GC-MS analysis on a Perkin–Elmer Turbo Mass system using an identical column and conditions with He as a carrier gas at 10 psi and comparison of the mass spectra with the NIST and Wiley libraries was obtained (Adams 1995). Factorial RBD was used to analyze herb yield, oil yield and oil quality of treatment combination planting dates (D) 6 cultivars (C) each year. Statistical analysis of the data was carried out following the procedure described in Panse and Sukhatme (1976). Results and discussion Herb yield Fresh herb yield increased gradually as planting dates shifted from 20 December to 18 February in both years, for all cultivars. With further delay (4 March) in planting of suckers, there was corresponding decrease in herb yield (Table 2). When planted on 4 March, the herb yield of Saksham, Kushal and Kosi was reduced by *24.53, 22.83 and 26.28%, respectively over its preceding date of planting (18 February). Balyan and Singh (1975) also observed a sharp decrease in herb yield up to 44.2% when planting was delayed from 1 March to 15 March under north Indian conditions (Jammu). The probable cause for the reduction in yield on late planting may be attributed to the exposure of suckers to higher daytime temperatures before sprouting and to the utilization of growth resources in the absence of a welldeveloped root system. It has generally been observed that delayed plant crop growth is stunted and matures early, giving less herb and oil yield compared with early planted crops. Highest herb yield was recorded with the crop planted on 18 February in all cultivars. Yield increased *85.71, 104.91 and 109.49% in Saksham, Kushal and Kosi, respectively over the 20 December planting. Average herb yield across all planting dates indicated that Kosi produced *5.68 and 10.75% higher herb yield than Saksham and Kushal, respectively. The order of herb yield produced with respect to planting dates was 18 February 4 3 February 4 4 March 4 19 January 4 4 January 4 20 December for all cultivars (Saksham, Kushal and Kosi) of menthol mint. An increase in herb yield of menthol mint planted during 19 January to 18 February may presumably be due to favorable climatic conditions for growth of the plant. The daytime temperature during the period was 22–258C for 3–5 weeks after planting of suckers, which was compatible with establishment of the crop. After the development of a proper root system, when exposed to higher temperatures, the crop

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Table 2. Effect of different date of planting on herb yield and dry matter production for three menthol mint cultivars in two years (2007–2009). Cultivars of Mentha arvensis (C) 2007–2008 Date of Sowing (D) Saksham Kushal 20 December 4 January 19 January 3 February 18 February 4 March Mean LSD at 0.05

20 December 4 January 19 January 3 February 18 February 4 March Mean LSD at 0.05

16.5 18.2 22.4 23.5 28.2 20.8 21.6

2.13 5.86 7.03 5.79 7.49 3.77 5.35

Kosi

2008–2009 Mean

Saksham Kushal

Kosi

Herb yield (t ha71) 13.6 13.6 14.6 12.2 12.9 13.8 15.6 20.5 18.1 13.8 14.9 15.8 18.2 24.4 21.7 15.1 16.4 17.6 21.7 26.2 23.8 20.7 23.8 25.1 27.4 28.5 28.0 25.1 26.9 28.0 20.1 23.5 21.5 22.0 22.9 22.5 19.4 22.8 18.5 19.6 20.5 D ¼ 2.0 D ¼ 2.2 C ¼ 1.7 C ¼ 1.5 D 6 C ¼ 2.5 D 6 C ¼ 1.8 Dry matter yield (t ha71) 3.49 3.09 2.90 3.07 3.44 3.56 3.83 4.69 4.79 4.63 3.34 3.63 6.55 6.89 6.82 4.69 3.99 4.25 5.99 8.52 6.77 5.40 6.90 6.55 8.46 9.92 8.62 6.99 7.47 7.83 5.57 4.73 4.69 5.67 7.01 5.48 5.65 6.31 5.08 5.36 5.22 D ¼ 7.4 D ¼ 6.5 C ¼ 5.3 C ¼ 4.6 D 6 C ¼ 12.9 D 6 C ¼ 11.4

Mean 12.9 14.8 16.4 23.2 26.7 22.5

3.36 3.87 4.31 6.28 7.43 6.05

Note: D, date of planting; C, cultivars.

increased in growth without any limitation. Kosi produced a higher herb yield than Saksham and Kushal, especially when planted on 3 February in both years and 18 February the second year. The higher yield of Kosi is presumed to be due to its specific architectural shape, in which all the shoots emerged at ground level, which probably allowed the plants to use sunlight from the top to the bottom leaves and thus protected the senescence of lower leaves by avoiding shading (Muni Ram et al. 2000). Crop growth and yield are results of the interaction between the weather that prevailed during the crop growth period and the genetic constitution of the crop plant. Dry matter yield The herb and dry matter yield of all cultivars (Saksham, Kushal and Kosi) of menthol mint were significantly affected by the different dates of planting (Table 2). Dry matter of all cultivars were significantly different by date of planting. Like herb yield, recorded dry matter was maximal when the crop was planted on 18 February for all cultivars. Kushal and Saksham accumulated relatively low dry matter when planted on 3 February in both years. However, Kosi followed a linear increase in dry matter as the date of planting shifted from January to February. Among the cultivars, Kosi produced *0.66 and 0.96 t ha71 more dry matter than Kushal and Sakshan, respectively. Dry matter yield was lowest when the crop was planted on 20

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December. Extremely low or very high temperature was not compatible for the sprouting of suckers and subsequent plant growth. Oil content Oil content is the most important factor contributing to essential oil yield. It varied significantly with date of planting in all cultivars (Table 3). On average, it increased as planting dates shifted from December to March, but higher oil content was recorded when the crop was planted in January to February. Highest oil content was found on 19 January, 3 February and 18 February in Kosi, Kushal and Saksham, respectively. This may be due to a higher leaf:stem ratio and an environment compatible with the development of monoterpenoids. Similar results were obtained by Prakash Rao et al. (2000) and Ramesh and Singh (2008). The reason for the lower oil content in the December-planted crop was perhaps that it could not reach physiological maturity, this corroborates with results of Singh et al. (1995). Oil yield Like herb yield, oil yield of all cultivars of menthol mint was also significantly affected by date of planting (Table 3). Herb and oil yields were maximal when all cultivars were planted on 18 February compared with other planting dates. Among Table 3. Effect of different date of planting on oil content and oil yield production in three menthol mint cultivars in two years (2007–2009). Cultivars of Mentha arvensis (C) 2007–2008 Date of sowing (D) 20 December 4 January 19 January 3 February 18 February 4 March Mean LSD at 0.05


Saksham Kushal Kosi 0.63 0.65 0.75 0.73 0.75 0.70 0.70

139.9 118.3 168.0 171.6 177.7 145.6 153.5

2008–2009 Mean Saksham Kushal Kosi

Oil content (%) 0.56 0.55 0.58 0.75 0.67 0.65 0.65 0.75 0.68 0.70 0.72 0.72 0.75 0.77 0.76 0.72 0.70 0.75 0.72 0.77 0.74 0.70 0.77 0.78 0.70 0.79 0.75 0.75 0.78 0.80 0.65 0.78 0.71 0.65 0.72 0.76 0.67 0.74 0.71 0.73 0.74 D ¼ 0.069 D ¼ 0.045 C ¼ 0.048 C ¼ NS D 6 C ¼ 0.12 D 6 C ¼ 0.079 Oil yield (l ha71) 76.2 74.8 96.9 93.0 83.1 91.3 112.3 135.8 122.1 107.0 100.4 105.1 136.5 187.9 164.1 116.7 128.3 124.8 141.1 201.7 171.5 144.8 173.1 196.5 186.3 225.6 196.5 195.2 215.2 223.2 130.6 183.3 153.2 137.0 174.3 153.4 130.5 168.2 132.3 145.7 149.1 D ¼ 18.74 D ¼ 18.34 C ¼ 10.32 C ¼ 12.97 D 6 C ¼ 29.79 D 6 C ¼ 13.77

Note: NS, not significant; D, date of planting; C, cultivars.

Mean 0.69 0.71 0.72 0.75 0.78 0.71

89.1 104.2 123.3 171.5 211.2 154.9


229

the cultivars, Kosi produced maximum levels essential oil, followed by Kushal and Saksham. The average oil yield ranged between 98.45 and 141.3, 79.65 and 152.45 and 83.05 and 168.35 l ha71 in Saksham, Kushal and Kosi, respectively, planted from 20 December to 4 March in both years. Although oil yield gradually increased as planting date shifted from December to February, there was sharp decline in oil yield when the crop was planted after February (4 March). An economically acceptable oil yield was produced by all the cultivars when planted between 3 February and 18 February. Oil yields averaged over years for Kosi were 199.08 and 224.42 l ha71 when planted on 3 February and 18 February, respectively. A similar pattern was seen in Saksham. The reduction in oil yield with early planting was mainly attributed to lower oil content and herb yield because oil yield is a function of herb and oil content. At later dates of planting in March, a higher temperature prevails during the sprouting of suckers and plant growth, which induced early maturity of the crop and higher losses of photosynthates. Averaged across the dates of planting Kosi produced *14.84 and 13.38 l ha71 more oil than Kushal and Saksham, respectively. Chemical composition of mint oil Mentha oil is made up of various chemical constituents, of which the predominant is menthol, which determines the quality of the oil as well as its market value. Menthol content in the oil of all cultivars varied with date of planting (Table 4). The highest menthol content recorded was 86.64% in Saksham, 85.51% in Kushal and 83.62% in Kosi planted on 18 February or 4 March, respectively; menthol content varied between 65 and 86%, 58 and 85% and 74 and 83% in Saksham, Kushal and Kosi, respectively. The highest value for menthol was in Kosi compared with the other cultivars. This is a unique character of Kosi, which increased the acceptability of the cultivar to farmers. Menthone, isomenthone and limonene content was maximal in the 20 December planted crop and decreased gradually as dates of planting were delayed towards March. Menthyl acetate and neomenthone did not follow any definite trend in response to different planting dates. Nitrogen, phosphorus and potassium in post-harvest soil The data (Table 5) indicated that maximum available nitrogen was found in soil planted with Saksham, Kushal and Kosi on 18 February and 4 January, respectively. Soil nitrogen content was low in all cultivars irrespective of date of planting, which is due to exhaustive uptake of N by the crops (Chand 1999). Soil cropped with Kosi on 4 January showed the highest level of available nitrogen compared with other dates of planting. This may be attributed to a higher rate of N mineralization prior to harvesting of the crop (second week of April) as a result of a gradual increase in environmental temperature and available soil moisture through frequent irrigation of the crop. Higher N availability is evidenced by the low herb yield of Kosi planted on 4 January compared with later planting dates. There is an inverse correlation between herb yield and available nitrogen for most of dates of planting. Nitrogen availablity for Saksham varieties planted on 20 December and 18 February is equal. Available phosphorus and potassium for all the three cultivars are highly different with respect to dates of planting. The available amounts of these two elements (P and K) are in either the medium or high range with respect to fertilizer application for

65.18 80.52 84.77 80.72 86.64 83.48 80.22

C1

C3

Mean

C1

C2

C3

Mean

Menthone (%)

72.72 74.53 70.81 10.25 9.83 9.01 9.70 58.93 76.16 71.87 5.44 6.23 7.28 6.32 82.89 82.13 83.26 5.17 4.38 3.88 4.48 85.11 78.62 81.48 6.02 3.49 5.96 5.16 82.73 81.69 83.68 2.99 4.84 3.48 3.77 85.51 83.62 84.20 4.75 3.87 4.74 4.45 77.98 79.46 5.77 5.44 5.73 D ¼ 2.66 D ¼ 0.94 C ¼ NS C ¼ NS D 6 C ¼ 4.61 D 6 C ¼ 1.63

C2

Menthol (%)

2.99 2.54 2.62 2.75 2.03 2.60

C1

C3

3.20 3.24 2.24 2.93 2.41 2.81 1.95 3.08 2.66 2.53 2.42 2.87 2.48 2.91 D ¼ 0.21 C ¼ 0.15 D 6 C ¼ 0.37

C2 3.14 2.57 2.61 2.59 2.41 2.65

Mean

Isomenthone (%)

3.45 1.25 0.32 0.61 0.34 0.29 1.04

C1

C3

3.05 1.93 0.98 1.66 0.37 0.79 0.30 1.26 0.34 1.15 0.15 0.54 0.87 1.22 D ¼ 0.33 C ¼ 0.23 D 6 C ¼ 0.57

C2

Limonene (%)

2.81 1.30 0.49 0.72 0.61 0.33

Mean

C3

2.15 1.94 1.42 1.46 1.84 1.92 2.36 2.14 2.25 1.81 1.05 0.77 1.85 1.67 D ¼ 0.57 C ¼ NS D 6 C ¼ NS

C2

2.10 1.79 1.74 2.01 2.02 0.97

Mean

Menthyl acetate (%)

2.20 2.49 1.46 1.53 2.00 1.10 1.80

C1

Effect of different dates of planting on essential oil constituents of menthol mint cultivars in both years (2007–2009).

Note: Data represent mean of two years. NS, not significant; C1, Saksham; C2; Kushal; C3, Kosi; D, date of planting; C, cultivars.


Date of sowing

Table 4.

1.55 2.02 1.80 1.82 1.91 2.39 1.92

C1

C3 2.58 3.15 1.54 1.96 1.91 1.88 1.57 1.87 2.17 2.06 2.46 2.51 2.04 2.24 D ¼ 0.23 C ¼ 0.16 D 6 C ¼ 0.39

C2

2.43 1.84 1.86 1.75 2.05 2.45

Mean

Neomenthone (%)

230 R.K. Chauhan et al.

173.6 164.7 146.3 154.5 175.6 168.3 163.8 D ¼ NS 9.75

20 December 4 January 19 January 3 February 18 February 4 March Mean LSD at 0.05 SEM+

138.9 168.3 145.2 153.7 131.7 135.4 145.5 C ¼ NS 6.90

Kushal

146.6 185.6 132.9 160.9 157.3 164.6 157.9 D 6 C ¼ NS 16.90

Kosi 153.03 172.87 141.47 156.37 154.87 156.10

Mean 39.98 62.05 79.82 73.15 88.01 82.06 70.84 D ¼ 5.64 1.98

Saksham 57.78 67.75 72.09 71.90 88.04 80.47 73.00 C ¼ NS 1.38

Kushal 77.62 59.58 60.67 88.55 84.55 87.47 76.41 D 6 C ¼ 9.77 2.97

Kosi

Phosphorus (kg ha71)

Note: Data represent mean of two years. D, Date of planting; C, cultivars; NS, not significant.

Saksham

Nitrogen (kg ha71)

58.46 93.13 70.86 77.86 86.86 83.33

Mean

172.7 249.34 364.09 275.95 289.93 371.56 287.26 D ¼ 63.43 13.11

Saksham

266.4 241.00 351.86 269.59 328.96 299.20 292.83 C ¼ NS 15.6

Kushal

264.98 301.17 287.49 292.72 369.80 219.56 289.29 D 6 C ¼ NS 38.23

Kosi

Potassium (kg ha71)

Available N, P and K in post-harvest soil cropped with three menthol mint cultivars (Saksham, Kushal and Kosi).

Date of planting

Table 5.

234.69 263.84 334.48 279.56 329.56 296.77

Mean

Archives of Agronomy and Soil Science 231

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crop success. The soil planted with Saksham on 3 February, Kushal on 18 February and Kosi on 19 January has maximum exchangeable potassium, which is *2 to 3 times more than the lowest available value. Conclusion This study clearly indicated that planting date had a profound effect on growth, herb yield, oil yield and oil quality for all cultivars of menthol mint in both years. The cultivars differed among themselves within the context of their date of planting. Among the cultivars, Kosi performed better in terms of herb yield, essential oil yield and oil quality, especially when planted on 18 February. Hence Kosi should be preferred for cultivation over the other cultivars of menthol mint. Acknowledgements Authors are thankful to Director CIMAP, Lucknow for providing the necessary facilities during the course of investigation.

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