Biodiversity and Conservation (2006) 15:2325–2338
DOI 10.1007/s10531-005-0770-z
Springer 2006
-1
Propagation and conservation of Picrorhiza kurrooa
Royle ex Benth.: an endangered Himalayan medicinal
herb of high commercial value
BHUWAN CHANDRA1, L.M.S. PALNI1,2,* and S.K. NANDI1
1
G. B. Pant Institute of Himalayan Environment & Development, Kosi-Katarmal, Almora-263 643,
Uttaranchal, India; 2State Biotechnology Programme, Government of Uttaranchal, Biotech Bhavan,
P. O. Haldi, Pantnagar, US Nagar-263 146, Uttaranchal, India; *Author for correspondence (e-mail:
lmspalni@rediffmail.com)
Received 19 April 2004; accepted in revised form 7 January 2005
Key words: Conservation, Conventional propagation, In vitro multiplication, Picrorhiza kurrooa
Abstract. Picrorhiza kurrooa Royle ex Benth., a high value medicinal herb of alpine Himalaya and
a source of hepatoprotective picrosides, is listed as ‘endangered’ due to heavy collection from its
natural habitat. The present report deals with successful propagation of this species using both
conventional and in vitro techniques. Vegetative propagation was achieved by rooting runner
cuttings with indole-3-butyric acid (IBA) or a-naphtheleneacetic acid (NAA) treatment before
planting. Nearly 87% rooting success was achieved by treatment of cuttings with 50.0 lM IBA.
Seeds were given a presoaking treatment with gibberellic acid (GA3), 6-benzylaminopurine (BAP)
or a combination of both to influence germination. More than 11-fold improvement in germination
was recorded in seeds treated with 250.0 lM GA3. In vitro shoot multiplication was achieved
through sprouting of axillary buds using nodal segment. Multiple shoots were formed following
culture for 3 weeks on Murashige and Skoog (MS; 1962. Physiologia Plantarum 15: 473–497)
medium containing 1.0 lM BAP. Cent percent rooting success, without basal callus formation, was
observed when individual microshoots were placed in MS medium supplemented with IBA. The
plantlets raised using conventional as well as tissue culture methods were hardened and successfully
established in the experimental field located at 2450 m elevation. In addition, strategies have been
discussed to encourage cultivation and in situ conservation of this highly valued medicinal herb so
as to reduce pressure on its natural populations.
Introduction
Picrorhiza kurrooa Royle ex Benth. (family: Scrophulariaceae; local/trade
name: Kutki), an important medicinal herb endemic to alpine Himalaya
(Thakur et al. 1989), is distributed between 2800–4800 m altitude. The extract
of runners and roots of this plant has been used since long in several
‘Ayurvedic’ preparations, prescribed in hepatic disorders. The plant is also
used in the traditional as well as modern systems of medicine as stomachic,
purgative, and antiperiodic agent, as a brain tonic and in dyspepsia and fever
(Hussain 1984; Kirtikar and Basu 1984). It is known to contain picroside I, II,
III and kutkoside as major bioactive compounds (Rastogi et al. 1949;
Kitagawa et al. 1969; Weinges et al. 1972; Jia et al. 1999).
2326
The plant perennates through underground runners and the period of active
growth is confined only to a few summer months. In nature, the plant regenerates both by vegetative means (underground runners) as well as through
seeds. The seed setting and seedling survival has been reported to be generally
poor in alpine plants (Pandey et al. 2000). In common with other Himalayan
medicinal herbs of high altitude regions, P. kurrooa is also being indiscriminately harvested, often well before seed setting, for subsequent trading of raw
material (Farooquee and Saxena 1996; Rai et al. 2000). At times the entire
plants are collected by unskilled persons. In addition, lack of organized cultivation has led to considerable depletion of its natural population resulting in
its listing as vulnerable species in Red Data Book (Nayar and Sastry 1990) and
subsequently under the ‘endangered’ species category, as per IUCN criteria.
The use of conventional (vegetative propagation, seed germination) and in vitro
techniques for rapid and mass propagation offers possibilities for ‘recovery’ of
endangered species, thus reducing the risk of extinction (Nadeem et al. 2000).
In view of the importance of this species, a holistic approach for the propagation of P. kurrooa, using both conventional as well as in vitro methods, and
strategies for its conservation have been described in this paper.
Material and methods
Plant material
Spikes (5–10 cm long, bearing capsules) and runners of Picrorhiza kurrooa
Royle ex Benth. were collected from Pindari (306¢ to 3915¢ N and 7055¢ to
805¢ E; 3400 m amsl, District Bageshwar, Uttaranchal) of Kumaun Himalaya
in October 1998. The spikes were brought to the laboratory, seeds were separated from the capsules, sorted, air-dried (room temperature, 3 days) and
used immediately for germination trials. Runners were also brought to the
laboratory, wrapped in moist papers, in plastic bags and used immediately for
vegetative and in vitro propagation studies.
Seed germination
Seeds were pretreated (24 h, dark) in beakers containing 25 ml aqueous solutions of various plant growth regulators (PGRs; all from Sigma Chemical Co.,
St. Louis, USA), namely gibberellic acid (GA3; 25.0 and 250.0 lM), 6-benzylaminopurine (BAP; 25.0 and 250.0 lM) and abscisic acid (ABA; 25.0 and
250.0 lM). The combined effect of GA3 and BAP (25.0 lM each) was also
examined. Stock solutions were prepared in 50% ethanol (v/v) and diluted with
water before treatment, so that the final concentration of ethanol in various
test solutions (including control) never exceeded 2.0% (v/v). Following various
treatments, the seeds were washed (· 2) with water and placed in petridishes
2327
over two layers of moistened filter paper; these were then kept in a seed germinator (Narang Scientific Works, New Delhi) at 10 or 20 C (dark). Each
treatment consisted of 20 seeds (in triplicate) and germination was monitored
weekly upto 10 weeks.
Vegetative propagation
Whole runners (including apical parts to the extreme basal portions) were cut
into small segments of 3.5–5.0 cm length (with 2–3 nodes) and treated with
various PGRs (12 h, dark) by dipping the basal portion (2.0 cm) of cuttings in
treatment solutions kept in separate glass beakers. The PGR treatments included indole-3-butyric acid (IBA; 50.0 lM), BAP (10.0 lM), IBA + BAP
(50.0 + 10.0 lM), a-naphthaleneacetic acid (NAA; 50.0 lM), NAA + BAP
(50.0 + 10.0 lM). The effect of Bavistin, a systemic fungicide (0.01% a.i.;
BASF India Ltd., Mumbai, India) was also examined. All treatment solutions
were prepared as mentioned above. Following treatment, the runner segments
were planted (one per cup) vertically in trays (20 cups per tray; cup diameter
5 cm, depth 10 cm, each cup contained approximately 185 g of a mixture of
soil and sand, 2:1), and kept in a mist chamber (25C, 90% RH) of a greenhouse under natural light (15% of ambient). Each treatment consisted of seven
cuttings (in triplicate). Data were recorded after 90 days.
Initiation of in vitro cultures and plant regeneration
Runners were cut into small segments (2.5–5.0 cm) with 2–3 nodes per segment. These were washed with Tween-80 (1%, 10 min) and successively surface
disinfected with mercuric chloride (HgCl2; 0.05%, 5 min), and sodium hypochlorite (NaHClO3; 2%, 5 min) solutions. Following surface disinfection the
nodal explants were thoroughly washed (· 4) with sterilized double distilled
water, and then placed vertically on Murashige and Skoog’s (1962) basal
medium containing 0.8% (w/v) agar and sucrose (2%, w/v), in tubes
(150 · 25 mm) containing 15 ml medium. The pH of the medium was adjusted
to 5.8 before autoclaving (1.05 kg/cm2, 121 C; 20 min). Cultures were maintained at 25 ±1C in 16/8 h light/dark cycle on racks fitted with cool fluorescent tubes (Philips 40 W; 42.0 and 60.0 lmol/m2/s irradiance inside and
outside the culture flasks, respectively). Subculturing was carried out at
4–6 weeks interval.
Statistical analyses
Least significant difference (LSD) and standard error (SE) were calculated
following the method of Snedecor and Cochran (1967).
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Results
Effect of PGRs on seed germination
Presoaking treatment with different PGRs and subsequent incubation at
10C resulted in only minor change in germination values (over control)
with the exception of 250.0 lM GA3 (Figure 1a). Treatment with GA3
(250.0 lM) caused a marked improvement (78.3% compared to 1.7% in
control) in germination in the 2nd week itself; thereafter the values increased
marginally and reached a plateau (83.3% compared to 15.0% in control)
within the next 8 weeks. This treatment also reduced the time taken for
germination as more than 80% germination occurred within the first
3 weeks (Figure 1a and Plate 1A).
Incubation at 20C generally improved germination significantly (over
control values) in almost all PGR treatments, except in case of ABA
(Figure 1b). Maximum increase was observed following treatment with
250.0 lM GA3, and even after 1 week 33.3% germination (compared to
0.0% in control) was recorded; this increased to 90.0 and 93.3% after 2nd
and 4th weeks, respectively, and then remained constant (Figure 1b). The
pattern of germination with PGR treatments (Figure 1b) was similar as in
Figure 1a, i.e., there was a marked increase in germination within the first
few weeks and subsequently the values remained constant (Figure 1a). Both
GA3 (25 and 250 lM) and BAP (25 lM), either alone or GA3+BAP
(25 lM each) were found to advance the time of germination. Although the
lower concentration of ABA (25 lM) resulted in marginal but significant
improvement in germination (LSD at p=0.05=17.5, at 4th week), it was
found to be inhibitory at higher (250 lM) concentration (Figure 1b).
Rooting of runner cuttings
Table 1 summarizes the effect of various PGRs on rooting. Among various
treatments, 50.0 lM IBA resulted in maximum rooting (86.7% compared to
53.3% in control) and highest root number (4.0 roots/cutting compared to
1.7 roots/cutting in control). Cuttings treated with 50.0 lM NAA, and the
combined treatments of NAA + BAP (50.0 + 10.0 lM) and IBA + BAP
(50.0+10.0 lM) also enhanced root formation (80.0% and above) as well as
stimulated number of roots (Plate 1B). Marginal, yet significant stimulation
(66.7%) in rooting was noticed when the cuttings were treated with 10.0 lM
BAP; however, bavistin did not show any stimulation (Table 1). Although
root initiation in cuttings treated with IBA and NAA was observed within
7–9 days of planting, the final rooting percent values in various treatments
were recorded after 90 days of planting.
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Control
GA3 250 µM
BAP 250 µM
ABA 25 µM
GA3 25 µM
BAP 25 µM
GA3+ BAP (25 µM)
ABA 250 µM
(a) 100
90
% Germination
80
70
60
50
40
30
20
10
0
1
2
3
4
5
10
1
2
3
4
5
10
(b) 100
90
% Germination
80
70
60
50
40
30
20
10
0
Time (Weeks)
Figure 1. Time course of P. kurrooa seed germination following PGR treatment. (a) Germination
at 10C, experiment conducted in triplicate with 20 seeds/petridish. Germination values remain
essentially unchanged during weeks 4–10; (b) Germination at 20C, experiment conducted in
triplicate with 20 seeds/petridish. Germination values remain essentially unchanged during weeks
4–10.
In vitro shoot multiplication
The nodal segments sprouted, giving rise to axillary shoots after 2 weeks of
inoculation on MS basal medium (Plate 1C). Only 60% explants were found to
be contamination-free after 4 weeks. These were further cultured on the same
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Table 1. Effect of various plant growth regulators and chemicals on rooting of runner cuttings of P. kurrooa.
Treatments
% Rooting
Avg. no. of
roots/cutting
Avg. no. of
sprouts/cutting
Avg. no. of
leaves/cutting
Avg. length of
roots (cm)
Avg. length of
longest root (cm)
Control
IBA (50 lM)
BAP (10 lM)
NAA (50 lM)
IBA (50 lM)+BAP (10 lM)
NAA (50 lM)+BAP (10 lM)
Bavistin (0.01%, a. i.)
LSD (p=0.05)
53.3±2.7
86.7±2.7
66.7±2.7
80.0±4.7
80.0±0.0
83.3±2.7
53.3±5.4
12.3
1.7±0.15
4.0±0.23
1.9±0.14
2.5±0.21
2.5±0.04
3.1±0.15
1.4±0.12
0.59
2.1±0.02
2.1±0.14
1.8±0.09
1.7±0.15
1.8±0.09
1.5±0.05
1.5±0.12
0.38
13.4±1.2
11.9±0.97
12.4±1.5
11.7±0.84
11.3±0.76
9.7±0.29
7.9±0.76
3.57
6.6±0.46
7.7±0.38
6.1±0.43
7.9±0.33
8.3±0.86
7.3±0.50
5.2±0.87
2.12
10.7±0.67
11.4±1.07
11.0±0.53
11.8±0.99
11.3±0.75
12.5±0.52
9.1±0.48
2.7
Data were recorded after 90 days of planting; n=7 (in triplicate); Mean±SE; a. i.=active ingredient.
2331
Plate 1. (A) Seedlings raised in thermocole trays and kept in the greenhouse; seeds were given
presoaking treatment with 250 lM GA3 in the dark for 24 h. (B) Plants raised through rooting of
runner cuttings treated with various plant growth regulators; 1: Control; 2: IBA (50.0 lM); 3: NAA
(50.0 lM); 4: IBA +BAP (50+10 lM); 5: NAA +BAP (50+10 lM). (C) A well-sprouted nodal
explant on MS basal medium 4 weeks after inoculation. The axillary shoots were excised and used
for further multiplication. (D) Multiple shoot formation on MS medium supplemented with
1.0 lM BAP and 2% sucrose. (E) IBA (1.0 lM) induced in vitro rooting of microshoots (bottom
view of the culture flask). (F) A well-rooted shoot, free from the formation of callus at the base of
the shoot, and ready for ex vitro transfer. (G) Hardened in vitro produced plants in earthen pots
under greenhouse conditions. The photograph was taken 4 months after ex vitro growth.
2332
medium for two more weeks. The axillary shoots were then separated from the
mother explants, i.e., nodal segments, and transferred on to MS medium
supplemented with 1.0 lM BAP. Multiple shoot formation started within
3 weeks in 66% of cultured shoots. The average number of shoots per cultured
axillary shoot was recorded to be 9.2 after 4 weeks of culture with a maximum
of 14 shoots from a single axillary shoot. These were further subcultured after
4 weeks in the form of shoot clumps (Plate 1D).
After two subcultures, the shoot clumps (five shoots per clump) were
transferred on to MS medium containing higher concentrations of BAP (2.5,
5.0 and 10.0 lM). While there was no significant improvement in shoot production at these concentrations, some callus formation was observed at the
base of the microshoots. Hence only 1.0 lM BAP was used routinely for shoot
proliferation.
Rooting of microshoots and hardening of plantlets
Transfer of individual microshoots (3.0–5.0 cm length) to MS basal medium
resulted in 66.7% rooting after 11 days of transfer to PGR-free medium
(Table 2). The rooting percentage could be improved (up to 100%) by the
addition of IBA (1.0 and 2.5 lM) in the MS medium. The time of root
initiation was also found to be advanced by 4 days in medium containing
2.5 lM IBA. The mean number of roots per shoot (5.4) was recorded to be
highest when 0.5 lM IBA was used and lower concentrations (0.5 and
1.0 lM) of IBA resulted in callus-free rooting (Plates 1E and F). Maximum
callusing (30.0%), however, occurred in MS basal medium. The rooted plants
were transplanted in thermocole cups containing a mixture of soil and sand
(1:1) and hardened under high relative humidity (80.0±5.0%) for 6 months
in the greenhouse with approximately 65% survival (Plate 1G). These plants
were then transferred to a high altitude field site (2450 m amsl, village
Khaljhuni in District Bageshwar) for further growth and monitoring, with
80% survival 3 month after field planting.
Table 2. Effect of different concentrations of IBA in the culture medium on rooting of
microshoots of P. kurrooa.
Treatment (lM)
% Rooting
No. of roots
Avg. length of
longest root (cm)
% shoots with
basal callus
Control
IBA 0.5
IBA 1.0
IBA 2.5
IBA 5.0
66.7±9.8
80.0±0.0
100.0±0.0
100.0±0.0
40.0±0.0
2.6±0.9
5.4±1.2
3.2±0.9
3.4±0.6
2.2±0.7
6.5
10.0
10.0
8.5
12.5
30.0±4.7
0.0
0.0
20.0±8.2
13.3±2.7
n=10 (in triplicate); Data were recorded 4 weeks after inoculation.
2333
Discussion
The germination was poor in freshly harvested seeds of P. kurrooa, both at 10
and 20C. This is possibly due to dormancy, exhibited by many alpine seeds as
an adaptation to overcome the harsh climatic conditions prevalent at high
altitudes (particularly after seed shedding in October), where naturally controlled germination can be crucial to seedling survival (Kaye 1997; Nadeem
et al. 2000; Pandey et al. 2000). Like many other alpine species, seeds of
P. kurrooa in nature are subjected to chilling at subzero temperatures during
winters which may assist germination in the following spring. Earlier report
(Nautiyal 1988) indicates upto 60% germination in P. kurrooa by incubation of
seeds at 20C in light. In a soil-based experiment inside a polyhouse upto 58%
seed germination has been reported without any chemical treatment when
seeds were sown in sandy loam soil covered with moss (Nautiyal et al. 2001). In
this study, presoaking treatment with GA3 significantly improved percent
germination (above 80%) and also reduced the time required for germination,
irrespective of the germination temperature. The seed treatment with GA3
(250.0 lM) is thus routinely being used for raising seedlings in the greenhouse
for subsequent field plantation (Plate 1a). Germination of various herbaceous
species, including those of alpine regions, is known to be accelerated by the
treatment of seeds with GA3 or BAP, or a combined treatment with both, as in
the present investigation (Son et al. 1999; Nadeem et al. 2000; Pandey et al.
2000). GA3 (250 lM) alone or in combination with BAP (250 lM) reportedly
doubled (over control values) germination as well as advanced the time taken
for germination in Podophyllum hexandrum, another alpine herb (Nadeem
et al. 2000). Germination of Aconitum balfourii and A. heterophyllum (both
alpine herbs) seeds could be significantly improved by the treatment of 250 lM
GA3 or 250 lM BAP (Pandey et al. 2000). Use of BAP (111.0 lM) alone has
been recently reported to improve germination of Gentiana scabra seeds by
upto 90% (Son et al. 1999). Thus GA3 is able to replace the chilling requirement of alpine seeds and/or break dormancy. It must be emphasized that lower
and physiological concentrations of PGRs should be applied to obtain a
response (Pandey et al. 2000). Cytokinins are also involved in breaking seed
dormancy and stimulation of germination (Walker et al. 1989); it has been
suggested that they may not be directly involved in the breaking of dormancy
but play a ‘permissive’ role by decreasing the level of germination inhibitors
and making the seeds more sensitive to gibberellins (Walker et al. 1989).
In this investigation, ABA inhibited seed germination both at 10 and 20C.
Literature reports indicate that ABA is involved in regulating the onset of
dormancy and maintaining the dormant state (Bewley 1997). Thus a dormant
state could be maintained over an extended period by exogenously applied
ABA.
Clonal propagation using ‘vegetative means’ provides a simple method for
multiplication of P. kurrooa. Nearly 87% rooting success could be achieved
when runner cuttings were treated with IBA or NAA, either alone or in
2334
combination with a low concentration of BAP (10.0 lM). While laboratory
scale multiplication using leafy explants and single node cuttings has been
reported for this species, no details were given (Ahuja 2001). In an earlier study
more than 90% rooting of apical segments taken from runners has been reported, however, rooting in basal cuttings was poor (39%; Nautiyal et al.
2001). In the present study, whole runners were used to obtain cuttings (in
which apical segments contribute only a small portion of around 10% of the
total cuttings made from each runner) and the observed average rooting success of nearly 87% is a significant advancement. As this is a listed endangered
species, the availability of material from nature for multiplication is limited;
hence the entire runners can be used for raising cuttings for large-scale propagation. Auxins are well-known as rooting agents and their application (naturally occurring or synthetic) for large-scale multiplication has been well
documented (Hartmann et al. 2002). It may be mentioned that IBA or NAA
treatment has been found to be effective for rooting rhizome/tuber segments of
Podophyllum hexandrum (Nadeem et al. 2000), Aconitum atrox (Rawat et al.
1992), and stem cuttings of Taxus baccata (Nandi et al. 1996) and Cedrus
deodara (Nandi et al. 2002), etc., high altitude Himalayan plants. In this
investigation, there was no improvement in percent rooting following bavistin
treatment although stimulation has been reported in certain gymnosperms, i.e.,
Taxus baccata and Cedrus deodara stem cuttings (Nandi et al. 1996, 2002).
Such an effect of this fungicide on rooting may be related to the auxin-like
property of carbendazim (Nandi et al. 2002).
In general cytokinins inhibit root induction in stem cuttings (Schrandolf and
Reinert 1959), however, root initiation was observed in pea cuttings when
applied at very low concentrations (Eriksen 1974). In this investigation, BAP, a
natural cytokinin (Nandi et al. 1989), either alone or in combination with IBA
or NAA significantly improved rooting of runner segments. Raising crops
through vegetative methods is not only useful for eliminating the difficulties
associated with seed germination and seedling survival, but it reduces the
overall duration of the cultivation cycle. In addition, being a clonal means of
propagation, genetic uniformity of the crop is assured.
In vitro multiplication of P. kurrooa has been achieved using nodal explant.
The application of BAP at lower concentrations (1.0 lM) has proven extremely beneficial for induction of multiple shoots and subsequent shoot
multiplication as also reported earlier (Lal et al. 1988; Upadhyay et al. 1989).
Higher concentrations of cytokinins like BAP and kinetin have been known to
result in lower shoot numbers and, in some cases, also inhibit shoot growth,
e.g., in Glycine max (Cheng et al. 1980). In this study, when higher concentrations (2.5–10.0 lM) of BAP were used during subsequent subculture, no
improvement in shoot multiplication was observed; however, 5.0–10.0 lM
BAP resulted in production of vitrified shoots with callus formation at the base
of microshoots. Transfer of vitrified shoots on medium containing lower levels
of cytokinins or a mixture of cytokinin and auxin at low concentrations
resulted in regeneration of normal shoots from the base of vitrified shoots.
2335
Vitrification of shoots in cytokinin supplemented medium has been reported
earlier in P. kurrooa (Upadhyay et al. 1989).
Rooting is an important step for developing a complete in vitro propagation
protocol. Successful rooting of microshoots in P. kurrooa could be achieved by
incorporation of an auxin in the culture medium. While the extent of in vitro
rooting has not been stated in an earlier report by Lal et al. (1988), good
rooting of microshoots was reported with 1.0 lM NAA in 20 days (Upadhyay
et al. 1989). In the present investigation, cent percent in vitro rooting of
microshoots has been observed with IBA (1.0 or 2.5 lM). Further, the time
required for root initiation was also reduced to 7 days; callus free rooting could
also be obtained in some cases.
Successful hardening and post-hardening establishment of in vitro raised
plants in a natural habitat is an important step towards propagation and
conservation of commercially valuable species. In vitro raised rooted plants of
P. kurrooa were hardened under greenhouse conditions, and after 6 months
these plants were transferred to a high altitude field station with 80% survival.
In continuation of the present study in vitro raised plants of P. kurrooa,
developed from cotyledonary node explants, have shown more than 90%
survival (as against 65% survival in the present study) during ex vitro hardening when the soil was inoculated with some bacterial isolates (e.g., Bacillus
subtilis) having antagonistic properties against selected pathogenic fungi
(Chandra et al. 2004). This is not surprising since maximum mortality is caused
by fungal infection during early weeks of transfer of rooted plants to the soil.
The growth of these plants was found to be identical to that of seedling or
cutting raised plants with normal runner formation. The 80% survival of tissue
culture raised plants following transfer to field, as observed in the present
study, can perhaps be improved if the time taken during transport of plantlets
from the hardening chamber to the field planting is reduced. Since the field site
was situated in a distant and difficult to reach place in the subalpine Himalayan
zone and replanting could be done only after 72 h, a major climatic shift, in
addition to transport shock, may have further affected the final survival in the
field.
Conclusions
Being included in the negative list of Indian plants export of P. kurrooa, in any
form, is not permitted by the Export Authority of India (Purohit 1997).
Majority of medicinal plants used by the pharmaceutical companies are presently harvested from their natural habitat. In order to facilitate collection and
marketing of medicinal plants, a co-operative has been set up by the State
Government that allows for the collection of these herbs through issue of a
license. However, illegal trade still continues due to low (and variable) price
offered by the co-operative, as compared to the open market price. For
example, in the neighbouring state of Uttar Pradesh, dried runners of
2336
P. kurrooa are purchased by the co-operative @ Rs. 22.25/kg (1 US $=approx.
Rs. 45.0) as against Rs. 56.0/kg in the open market (Purohit 1997) and in the
state of Sikkim the price is Rs. 202.0/kg (Rai et al. 2000). Apart from providing
scientific back up for mass propagation of elite material (in close proximity of
field sites), a prerequisite for promoting organized cultivation of medicinal
plants, it is crucial that the State Forest Departments, non-governmental
organizations and Government policies should be in the interest of farmers,
and work towards minimizing the intervention of middle men and illegal
traders.
Habitat protection and proper management of existing populations provide
far better options to conserve rare and endangered plant species. Since this
species in particular and collection and trade of medicinal plants in general
form an important part of the economic activity in the region, it is imperative
that improvement in propagation techniques, both conventional and tissue
culture based methods, and eventually the domestication of relevant species
will serve the purpose of providing alternate cash crops for the farmers. These
efforts will substantially ease the pressure on unregulated exploitation from the
natural populations by fulfilling the demand of the traders. Based on the
findings reported in this communication, farmers may be provided trainings
and readymade solutions in easy to use form for raising nurseries using seeds
and runner segments. Some efforts should also be placed in identifying elite
populations (in terms of active ingredient content) suitable for raising large
number of propagules.
In spite of the endangered status of P. kurrooa (Samant et al. 1998) there
have been very few attempts to restore its natural status and/or to initiate
cultivation. In this regard, the propagation protocols reported in this communication will be useful for initiating a programme on systematic cultivation
of this high value species. Presently efforts are also in progress to develop
farmer friendly package of agrotechnniques at the high altitude field station.
Thus, demonstration of propagation techniques and distribution of elite
propagules to farmers interested in their commercial cultivation, will pave the
way for in situ conservation of endangered species like P. kurrooa.
Acknowledgement
The financial assistance provided by the Department of Biotechnology and the
Ministry of Environment, Govt. of India, New Delhi is gratefully acknowledged.
References
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Samant S.S., Dhar U. and Palni L.M.S. (eds), Himalayan Medicinal Plants: Potential and
Prospects. Gyanodaya Prakashan, Nainital, pp. 207–230.
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