Study on Weed Flora and Their Influence on Patchouli (Pogostemon cablin Benth.) Oil and Patchoulol
Experiments were conducted to study the weed flora and its influence on the yield of oil and Patchoulol by co-distillation of fresh Patchouli leaves with weed biomass at different proportions (0, 5, 10, 15 and 30%) during 2004-05 and 2005-06. The survey of weeds commonly growing in patchouli plantation was made and a total of 17 weed species were recorded. Alternanthera sessile, Cynodon dactylon and Oxalis cornicullata exhibited 100% frequency in both the years. A. sessile, C. dactylon and O. cornicullata had highest density during 1st year and the density of most of the weed species increased during 2nd year except C. dactylon and A. sessile. Co-distillation of fresh Patchouli leaves with weeds at the rate of 0, 5, 10,15 and 30% yielded 0.70, 0.67, 0.65, 0.50 and 0.43% oil, respectively. It was observed that the oil yield decreased gradually with the increase in weed biomass. However, the percentage of patchoulol showed a different behaviour. It decreased at 15% (53.7) and 30% (50.4) and increased at 5% (56.5) and 10% (63.8) treatments. The oil extracted with weed biomass imports a weedy odour, which may decrease its commercial value.
Pogostemon cablin Benth. (Patchouli) belonging to family Lamiaceae,
a native to South East Asia, is long been used as a moth repellent. It is a
perennial, bushy plant grows up to 1 m (3 feet) high, with a sturdy, hairy stem
and large, fragrant, furry leaves, about four inches long and five inches across.
It has whitish flowers tinged with purple. The word is derived from Hindustan
word patch meaning green and ilai meaning leaf. Patchouli oil has a rich musky-sweet,
strong spicy, herbaceous smell and dark orange or brownish colored viscous liquid.
Because of its oriental notes and its strong fixative properties, it is one
of the most important essential oil utilized in the perfumery, flavour and cosmetic
industries for manufacture of soaps, detergents, deodorants etc. (Akhila
and Tewari, 1984; Maheshari et al., 1993;
Sarma and Sarma, 2003). Newly distilled oil has a fresh
green slightly harsh aroma. As the oil ages, it mellows considerably becoming
sweeter and balsamic. Nikiforov et al. (1988
and 1989) proved that (-)-patchoulol was the predominant
odor component of patchouli oil by using chiral phase gas chromatography combined
with a sniffing-technique.
Patchouli is grown mainly in Indonesia, Malaysia, China, Brazil and India.
Various natural and controllable factors could affect the yield and quality
of oil such as soil heterogeneity (Sugimura et al.,
1990), quality of planting material (Sharma, 1999)
and cultivation practices (Sarma and Kanjilal, 2000).Weeds
are constant component of agro-ecosystem and alternative control methods have
been used to control them in different crops (Powell and
Justum, 1993). Due to wider gap during the initial plantation, the weeds
become dominant in field (Yadav et al., 1981).
However many seeds of exotic species are introduced in new regions by accident
and some of them may settle and become component of the natural flora (Maillet
and Lopez-Garcia, 2000). Weeds compete with crop plants for light, water
and nutrients. Weed management practice significantly increased the yield attributes
and yield over the control (Sharma et al., 2002).
Some of the grass species grow in close proximity to the base of the plants
and often their branches and leaves get intermingled with branches of the crop.
During harvest such weeds get mixed with the crop and distilled along with crop
biomass. Therefore, an experiment was conducted to study the weed flora under
plantation and its effect on combined distillation of patchouli leaves and weed
biomass on the yield of oil and patchoulol.
Materials and Methods
Trials were conducted at Regional Research Laboratory, Jorhat (Assam) during
2004-2006. The area is located at 96.5 msl. and the climate is worm humid. Annual
average rainfall is about 2000 mm and rainy season began in early part of April
and continues till October. The maximum temperature does not exceed 40°C
and winter temperature does not fall below 5°C. The soil of the experimental
field is sandy loam in texture and acidic (pH 5.5) in reaction. The field was
thoroughly ploughed and harrowed before making experimental plots. Patchouli
cuttings were planted in mid February 2004 and regularly irrigated to ascertain
The experiment, having two treatments comprising of weed free plots (weeded
manually) and weed infested plots (weeds were allowed to grow), was laid out
in a randomized block design having four replications. Plot size was 10x10 m
and each plot was separated by 1.5 m. Patchouli cuttings were planted at intra-row
spacing of 60 cm apart. Two weeks before plantation, N 25, P2O5
50 and K2O 50 Kg ha-1 along with 8 tons of well
rotten compost was basally applied. The remaining 75 Kg N was applied in equal
three split doses after each harvest as side dressing.
Sampling Procedure and Data Analysis
Sampling was made from randomly selected plots using 1 m2 quadrate
for 5 times plot-1. Weed species were separately counted from each
quadrate and identified. To eliminate the influence of field edges on survey,
sampling was made inside the field. Frequency and density of each weed species
were determined and calculated according to Odum (1971).
Ecological analysis of the weed flora was carried out to determine the relative
frequency and density using the equation provided by Wirjahadja and Panch (1975).
Weeds were collected from the plots and its dry weight (t ha-1)
Fully-grown Patchouli plants were harvested and weeds were collected separately.
Specific proportion of weed biomass was mixed with patchouli leaves at the rate
of 5, 10, 15 and 30% along with a control (weed free) for hydro distillation
in Clevengers apparatus for 16 h. Extraction of oil was repeated for 10
times for each treatment and average data were presented in Table
3. Weed biomass alone was also distilled to ascertain the presence or absent
of any oil.
The patchoulol of oil was determined by gas chromatography method. A Chemito
model 3865 GC with FID and a Hewlett Packard HP 3395 data integrator was used
for the analysis. The constituents in the oil were separated in a packed glass
column (2 mm idx2 M length) of 15% SE 52 on gas chrom Q, 80/100 mesh.
Results and Discussion
A total of 17 weed species were growing in patchouli plantation and enumerated
in Table 1. The frequency of weed species ≥ 75% were Oxalis
cornicullata (100%), Cynodon dactylon (100%), Alternanthera sessile
(100%), Ageratum conizoides (95%), Spilanthes oleraceae (85%)
and Amaranthus spinosus (75%) during 1st year (2004-2005). In 2nd year
(2005-2006), the frequency of majority of weed species was increased. The frequencies
were 100% in case of A. conizoides, A. sessile and Oxalis cornicullata
followed by C. dactylon (98%) and A. spinosus (80%)
The weed density of 3 species was ≥ 10 plants m-2 during 1st
year. C. dactylon exhibited the highest density (21 plants m-2)
followed by O. cornicullata (18 plants m-2) and A. sessile
(12 plants m-2). It was observed that the density of most of
the weed species increased during 2nd year except C. dactylon (9.5%)
and A. sessile (16.7%)
The high number of weed species might be attributed to the fact that patchouli
provides poor shading during initial stage and take longer time (29-32 days)
to attain its full growth, which gave the weeds an advantage to become well
established. The earlier the weed emerges prior to crop, the more time it has
to established and compete (Chapman, 2000).
Table 2 shows the relative frequency of various weed species
indicates the rate of occurrence of weed was relatively higher during 1st year
than 2nd year. Patchouli was predominately invaded by A. conizoides,
O. cornicullata, C. dactylon, S. oleraceae and A. sessile.
The decrease in relative frequency in the 2nd year might probably due to increase
in plant growth providing shade.
In patchouli plots only 3 weed species occurred at relative density ≥
10% in 2004-2005. (Table 2) of these C. dactylon produced
the highest density relative to O. cornicullata and A. sessile.
In 2nd year relative density of Portulaca quadrifida observed to be increased
from 1.94% in 1st year to 10.84% in 2nd year, while that of O. cornicullata,
C. dactylon and A. sessile decreased considerabily. The relative
density of A. conizoides, Cyperus prolifer, Mimosa pudica and
Mikania macrantha was also fairly increased during 2005-2006, which might
be attributed to their higher growth rate.
Oil yield and GC Analysis
The oil yield and chemical profile of patchouli oil were reported in detail
earlier (Lawrence, 1976, 1981,
1990, 1995; Akhila
and Nigam, 1984). Weed biomass did not yield any oil. Whereas, presence
of weed during co-distillation contributed additional biomass to the patchouli
|| Enumeration of weeds in patchouli plantation, their frequency
|| Relative frequency and density of weed species during 2004-2005
|| Yield of oil and patchoulol as affected by co-distillation
under different treatments
|+ indicates increase, - indicates decrease
Therefore, increase proportions of weed co-distilled with patchouli resulted
in decrease of oil progressively. The oil yields were 0.70, 0.67, 0.65, 0.50
and 0.43% at 0, 5, 10, 15 and 30% weed treatments, respectively. Co-distillation
with different proportions of weed biomass showed a variation in patchoulol
content, which were 54.9, 56.5, 63.8, 53.7 and 50.4% at 0, 5, 10, 15 and 30%
weeds treatment, respectively (Fig. 1). It was observed that
patchoulol was gradually increased up to 10% weed-patchouli mixture showing
maximum of 63.8% at 10% and then gradually decreased showing minimum of 50.4%
at 30% (Table 3). Variation in patchoulol content may be due
to interaction with water-soluble chemicals released by weed species into distillation
water during co-distillation.
|| Effect of co-distillation of patchouli and weed on oil and
Similar results were also reported by Rao et al.
(2005) on rose scented geranium sp. Although, the weeds did not yield any
oil, it imports a weedy odour to the distillation water as well as patchouli
oil comparing to the control (Kaul et al., 1997).
It is imperative that the quality of patchouli oil is based on higher percentage of patchouli alcohol (patchoulol) and odour profile. Proper care should be taken to avoid mixing of weed with patchouli during distillation as it imparts weedy odour and decrease oil yield.
1: Akhila, A. and M.C. Nigam, 1984. GC-MS analysis of the essential oil of Pogostemon cablin (Paychouli oil). Fitoterapia, 55: 363-365.
2: Akhila, A. and R. Tewari, 1984. Chemistry of patchouli oil: A review. CROMAP, 6: 38-54.
3: Chapman, B., 2000. Effect of weed in wheat. Top Document. Agricultural Food and Rural Development, pp: 25.
4: Kaul, P.N., B.R.R. Rao, A.K. Bhattacharaya, K. Singh and C.P. Singh, 1997. Effect of partial shade on essential oils of three geranium (Pelargonium species) cultivar. Ind. Perfumer, 41: 1-4.
5: Lawrence, B.M., 1976. Progress in essential oils-Patchouli oil. Perfum. Flavor., 1: 20-20.
6: Lawrence, B.M., 1981. Progress in essential oils-Patchouli oil. Perfum. Flavor., 6: 73-76.
7: Lawrence, B.M., 1990. Progress in essential oils-Patchouli oil. Perfum. Flavor., 15: 76-77.
8: Lawrence, B.M., 1995. Progress in essential oils-Patchouli oil. Perfum. Flavor., 20: 72-73.
9: Maheshari, M.L., K.T. Vasantha, N. Sharma and K.P.S. Chandel, 1993. Patchouli-an Indian Perspective. Ind. Perfum., 37: 9-11.
10: Maillet, J. and G.C. Lopez, 2000. What criteria are relevant for predicting the invasive capacity of a new agricultural weed? The case of invasive American species in France. Weed Res., 40: 11-26.
11: Nikiforov, A., L. Jirovetz, G. Buchbauer and V. Raverdino, 1988. GC-FTIR and GC-MS in odour analysis of essential oils. Mikrochim. Acta, 2: 193-198.
12: Nikiforov, A., L. Jirovetz and G. Buchbauer, 1989. Synthesis of tertiary alcohol carbamates. Liebigs Ann. Chem., 5: 489-491.
13: Odum, E.P., 1971. Fundamentals of Ecology. 3rd Edn., W.B. Saunders Company, Philadelphia, Pages: 574
14: Powell, K. and A.R. Jutsum, 1993. Technical and commercial aspects of bio control products. Pest. Sci., 37: 315-321.
15: Rao, B.R.R., P.N. Kaul, K. Singh, G.R. Mallavarapu and S. Ramesh, 2005. Influence of Co-distillation with weed Biomass on yield and chemical composition of Rose- Scented Geranium (Pelargonium species) Oil. J. Essential Oil Res., 17: 41-43.
Direct Link |
16: Sarma, P.C. and P.B. Kanjilal, 2000. Effect of planting time and row spacing on growth yield and quality of Patchouli (Pogostemon patchouli Benth). Adv. Plant Sci., 13: 201-204.
17: Sarma, A. and T.C. Sarma, 2003. Patchouli oil recovery and effect of leaf ageing. Ind. Perfumer, 47: 151-154.
Direct Link |
18: Sharma, N., 1999. Coservation of Patchouli (Pogostemen patchouli) through in vitro methods. Ind. Perfum., 43: 19-22.
19: Sharma, R.P., P. Singh and P.L. Maliwal, 2002. Effect of weed management and phosphrous level on yield and qualiy of Indian mustard (Brassica juncea). Ind. J. Agric. Sci., 72: 461-463.
Direct Link |
20: Sugimura, Y., Y. Ichikawa, K. Otsuji, M. Fujita and N. Toi et al., 1990. An cultivarietal comparison of patchouli plants in relation to essential oil production and quality. Flavour Fragrance J., 5: 109-114.
21: Wirjahadja, S.D. and J.Y. Pancho, 1978. Weed survey method and vegetation analysis. Biotrop. Tech. Bull., 4: 20-20.
22: Yadav, R.L., R. Mohan and D.V. Singh, 1981. Requirement of weed free period for optimum herb and oil yield of Java citronell. Ind. Perfum., 25: 47-52.