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Milk thistle (Silybum marianum (L.) Gaertn.) as a weed in sustainable crop rotation

  • January 2012
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Štefan Týr at Slovak University of Agriculture in Nitra - Slovenska posnohospodarska univerzita v Nitre
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Abstract

Milk thistle – Silybum marianum (L.) Gaertn. can be a winter annual or a biennial medicinal plant. The assessment of the occurrence of milk thistle in sustainable crop rotation was conducted at the Experimental Base of Faculty of Agrobiology and Food Resources, SUA in Nitra in the years 2008-2011. This study was focused on milk thistle as a weed in the sustainable farming system with the crop rotation of maize for grain, pea for grain, durum wheat and milk thistle. An actual weed infestation of maize, pea and durum wheat stands with milk thistle was evaluated before preemergence application of herbicides, in the spring time. Second screening of actual weed infestation of all stands in sustainable crop rotation with milk thistle was done before crops harvest. Screening of each field was made on 1 m 2 area with three replications. The three randomly established sample quadrants were situated minimally 10 m from field margin and apart from each other, respectively. The level of infestation was evaluated according to average density of weeds per square meter. Obtained data was statistically analyzed by Statistica 7.0, ANOVA, LSD test (p=0.05). As a plant from the family Asteraceae has a great anticipation to have vital seeds in soil profile for long time as well as Helianthus annus. On the base of our 4 vegetation periods research, we can conclude that the S. marianum seeds are vital in soil profile for three and more years. We can also conclude that in third year after milk thistle cropping was no infestation of durum wheat, but S. marianum germinate after the harvest of durum wheat at the stubbles in August or September. According to statistical analyses in the year 2010 was the maize stands infested with the highest, statistically very significant amount of Silybum marianum (7 plants per m 2). Stands of pea for grain in the second year after milk thistle cropping were infested in the years 2008-2010 only with 0.33 plants per m 2 . Durum wheat stands were not infested with milk thistle. In the spring time the infestation of maize for grain, pea for grain and durum wheat stands with milk thistle falled very significantly down from 17.78 plant pre m 2 in maize stand to 2.56 plant pre m 2 in durum wheat stand. The originality of this paper is in the examination of new perspective crop in sustainable farming systems and in evaluating of its weed potential.
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Research Journal of Agricultural Science, 44 (2), 2012
118
MILK THISTLE (SILYBUM MARIANUM (L.) GAERTN.) AS A WEED IN
SUSTAINABLE CROP ROTATION
T. VEREŠ, Š. TÝR
Slovak Agricultural University in Nitra, Slovak Republic
Faculty of Agrobiology and Food Resources,
Slovak Agricultural University in Nitra,
Tr. A. Hlinku 2, 949 76 Nitra, Slovak Republic,
E-mail: Tomas.Veres@uniag.sk
Abstract: Milk thistle – Silybum marianum (L.)
Gaertn. can be a winter annual or a biennial
medicinal plant. The assessment of the occurrence
of milk thistle in sustainable crop rotation was
conducted at the Experimental Base of Faculty of
Agrobiology and Food Resources, SUA in Nitra in
the years 2008- 2011. This study was focused on
milk thistle as a weed in the sustainable farming
system with the crop rotation of maize for grain,
pea for grain, durum wheat and milk thistle. An
actual weed infestation of maize, pea and durum
wheat stands with milk thistle was evaluated before
preemergence application of herbicides, in the
spring time. Second screening of actual weed
infestation of all stands in sustainable crop rotation
with milk thistle was done before crops harvest.
Screening of each field was made on 1 m2 area with
three replications. The three randomly established
sample quadrants were situated minimally 10 m
from field margin and apart from each other,
respectively. The level of infestation was evaluated
according to average density of weeds per square
meter. Obtained data was statistically analyzed by
Statistica 7.0, ANOVA, LSD test (p=0.05). As a
plant from the family Asteraceae has a great
anticipation to have vital seeds in soil profile for
long time as well as Helianthus annus. On the base
of our 4 vegetation periods research, we can
conclude that the S. marianum seeds are vital in
soil profile for three and more years. We can also
conclude that in third year after milk thistle
cropping was no infestation of durum wheat, but S.
marianum germinate after the harvest of durum
wheat at the stubbles in August or September.
According to statistical analyses in the year 2010
was the maize stands infested with the highest,
statistically very significant amount of Silybum
marianum (7 plants per m2). Stands of pea for
grain in the second year after milk thistle cropping
were infested in the years 2008-2010 only with 0.33
plants per m2. Durum wheat stands were not
infested with milk thistle. In the spring time the
infestation of maize for grain, pea for grain and
durum wheat stands with milk thistle falled very
significantly down from 17.78 plant pre m2 in
maize stand to 2.56 plant pre m2 in durum wheat
stand. The originality of this paper is in the
examination of new perspective crop in sustainable
farming systems and in evaluating of its weed
potential.
Key words: weed infestation, Sylibum marianum L. Geartn., sustainable crop rotation
INTRODUCTION
Milk thistle (Silybum marianum [L.] Gaertn.) can be a winter annual or a biennial herb
(YOUNG et al., 1978; AUSTIN et al., 1988; GROVES, KAYE 1989). Its current distribution
includes most temperatures areas of the world (CHAMBREAU, MACLAREN, 2007). It is a broad-
leaved species belonging to Asteraceae that reaches a height of 200-250 cm (OMIDBAIGI,
NOBAKHT, 2001). Milk thistle is grown commercially as a medicinal plant in Europe, Egypt,
China and Argentina but it has been reported as a noxious weed in many other countries
(KHAN et al., 2009).
Milk thistle is a medicinal plant cultivated in agriculture. It is the most researched
plant for the treatment of liver disease. The achenes, i.e. fruits of the plant, are commonly used
as a medicinal drug; they are the raw material for isolation of different substances with liver-
protection activity. Its therapeutic properties are due to the presence of silymarin. The seeds
Research Journal of Agricultural Science, 44 (2), 2012
119
contain the highest amount of silymarin, but the whole plant is used medicinally. Milk thistle is
grown successfully on a range of soil types, from sandy soils to much heavier clay soils. Milk
thistle is directly seeded in soils. Sowing occurs in autumn and spring, and row spacing is
usually 40 – 75 cm, with 20 – 30 cm between plants in the row. Nutrient requirements of this
crop are low to moderate since it is adapted to poor quality soils and many different growing
conditions. Milk thistle is good forecrop for maize in sustainable agricultural system. A
limiting factor in milk thistle production is weed interference. Pendimethalin and metribuzin
herbicides are safe for weed control in milk thistle, both alone and in combination. Milk thistle
is considered drought resistant and normal rainfall will often suffice. In a Mediterranean
environment, under severe drought conditions, the crops should be irrigated during seed
growth and filling. Moreover, a few varieties of milk thistle have been developed (CARRUBBA
et al., 1987; HABÁN et al., 2009; KARKANIS et al., 2011; MACÁK et al., 2007).
It is considered to be ruderal, or weedy, in its native range, is found in dense stands
along roadsides and waste areas, and it prefers fertile soils (GABAY et al., 1994).
In this study we focused on milk thistle as a weed in the sustainable farming system
with the crop rotation of maize for grain, pea for grain, durum wheat and milk thistle.
MATERIAL AND METHODS
The assessment of Silybum marianum (L.) Geartn occurrence in sustainable crop
rotation (Table 1) was conducted at the Experimental Base of Faculty of Agrobiology and food
resources, Slovak University of Agriculture in Nitra in the years 2008- 2011. Experimental
base is situated in cadastre of Dolná Malanta village near Nitra, Slovakia (18°07'E, 48°19'N).
Geographically, this locality is situated in the western part of the river Žitava upland. The
experimental locality has flat character with little declination to south. The altitude is 177 – 180
m above sea level (Hanes et al., 1993).
The weed mapping was realized in the framework of agri-climatic areas in the
territory with the following features: Macro area: warm with the sum of temperature during
days when t > 10°C in a range of 3,100 – 2,400°C; Area: predominantly warm with
temperature t > 15°C in a range of 3,000 – 2,800°C; Sub area: very dry with climatic humidity
factor for the months June–August KVI – VIII = 150 mm; Ward: predominantly mild winter
with the average of absolute temperature minimum Tmin. = from – 18 to – 21°C. The average
annual temperature in 2004 was 10.0°C, in 2005: 9.6°C, in 2006: 10.1°C, and in 2007: 11.4°C.
The sum of annual precipitations was: in 2004: 514.5 mm, in 2005: 633.0 mm, in 2006: 507.0
mm, and in 2007: 606.4 mm. The average long – term (1961–1990) annual precipitation is
532.5 mm, for the vegetation period it is 309.4 mm. The average long – term (1961 – 1990)
annual temperature is 9.8°C and for the vegetation period it is 16.4°C (Špánik et al., 1996).
Type of the soil is brown soil; selected soil properties were: proportional soil weight 2.60 –
2.63 t.m-3 content of humus in arable soil/topsoil 1.95 – 2.28%; soil reaction 5.03 – 5.69
(acidic, almost mild acidic). The experimental soil was created at the proluvial sediments. The
soil profile of brown soil contains three genetic horizons (Ap, Bt, C). Their stratography is
following: humus horizon (Ap) with the depth of 0–0.32 m; underneath is the main diagnostic
luvisolic horizon (Bt), which was created as a result of alluvial accumulation of translocated
colloids, and whose depth is from 0.33 to 0.65 m; then, there is a transitional horizon (Bt/C)
with the depth from 0.66 to 0.85 m followed continually with the soil forming substrate up to
the depth of 1.5 m. The studied brown soil is clayey in its sub – layer and in its topsoil is
mildly firm. Humus is of a humo – phulvate type (HANES et al., 1993).
An actual weed infestation of maize, peas and durum wheat stands with milk thistle
was evaluated before preemergence application of herbicides, in the spring time. Second
screening of actual weed infestation of all stands in sustainable crop rotation with milk thistle
Research Journal of Agricultural Science, 44 (2), 2012
120
was done before crops harvest. Screening of each field was made on 1 m2 area with three
replications. The three randomly established sample quadrants were situated minimally 10 m
from field margin and apart from each other, respectively. The level of infestation was
evaluated according to average density of weeds per square meter (Table 2). Obtained data was
statistically analyzed by Statistica 7.0, analysis of variance (ANOVA), LSD test (p=0.05).
Table 1
Sustainable crop rotation on the Experimental Base Dolná Malanta
2008 2009 2010 2011
Pea for grain Durum Wheat Milk Thistle Maize for grain
Maize for grain Pea for grain Durum Wheat Milk Thistle
Milk Thistle Maize for grain Pea for grain Durum Wheat
Durum Wheat Milk Thistle Maize for grain Pea for grain
Table 2
Evaluation scale of actual weed infestation
Actual weed infestation
none weak low medium heavy
Infestation level
0 1 2 3 4
Group of weeds*
Number of weeds per m2
Excessively dangerous - 2 3-5 6-15 ≥ 16
Less dangerous - 4 5-8 9-20 ≥ 21
Less important - 8 9-15 16-30 ≥ 31
*- weed species checklist Hron-Vodák, 1959, modified by authors Smatana-Týr, 2011.
RESULTS AND DISCUSSIONS
Milk thistle (Sylibum marianum L. Gaertn.) was in sustainable crop rotation the
forecrop for maize for grain. Because of this the highest infestation with S. marianum was
determined in maize for grain stands. The amount of Sylibum marianum seeds in the soil seed
bank fall statistically significantly down during the planting of cultural crops in the second and
third year after milk thistle (Table 3). Table 3
Number of Sylibum marianum (L.) Gaertn. plants per m2 in sustainable crop rotation in the spring time in
three different crops (LSD test, p=0.05)
Crop Number of SYLMA plants per m2 in the spring time
Maize for grain 17.78 C
Pea for grain 8.11 B
Durum Wheat 2.56 A
The highest amount of Sylibum marianum weeds before harvest was statistically very
significant in the year 2010 and in maize for grain stand (table 4; table 5).
Table 4
Number of Sylibum marianum (L.) Gaertn. plants per m2 in sustainable crop rotation before harvest in the
years 2008-2010 (LSD test, p=0.05)
Year Number of SYLMA plants per m2 before harvest
2008 0.9 A
2009 0.9 A
2010 2.5 B
Research Journal of Agricultural Science, 44 (2), 2012
121
Table 5
Number of Sylibum marianum (L.) Gaertn. plants per m2 in sustainable crop rotation before harvest in
different crops (LSD test, p=0.05)
Crop Number of SYLMA plants per m2 before harvest
Maize for grain 3.89 B
Pea for grain 0.33 A
Durum Wheat 0 A
According to statistical analyses (Table 6) in the year 2010 was the maize stands
infested with the highest statistically very significant amount of S. marianum (7 plants per m2).
Stands of pea for grain in the second year after milk thistle cropping were infested in the years
2008-2010 only with 0.33 plants per m2. Durum wheat stands were not infested with Sylibum
marianum. Table 6
Interaction between year and crop affected by number of Sylibum marianum (L.) Gaertn. plants per m2 in
sustainable crop rotation before harvest in different crops (LSD test, p=0.05)
Number of SYLMA plants per m2 before harvest 2008 2009 2010
Maize for grain 2.33 B 2.33 B 7.0 C
Pea for grain 0.33 A 0.33 A 0.33 A
Durum Wheat 0 A 0 A 0 A
Silybum marianum is not only cultivated crop which suffer from crop – weed
competition but Sylibum marianum is also important weed of grains (winter wheat) (MARTWAT
et al., 2007). It’s a serious weed in many areas of North and South America, Africa, Australia,
Asia and Middle East (HOLM et al., 1997). It can be found as a garden ornamental and shows
up in flower and vegetable seed packets. Once milk thistle has found a niche, it is a competitive
thistle and tends to establish in tall dense patches that eliminate other plant species, either by
shading or by competition for water and nutrients (BERNER et al., 2002).
CONCLUSIONS
Milk thistle (Silybum marianum (L.) Gaertn.) was ranged into sustainable crop rotation,
because of integrated soil management and economical rentability of its cropping. S. marianum as
medicinal plant is used in pharmacy for silymarin isolation from its fruits. But the cropping of milk thistle
has several disadvantages: the first is its morphological characteristics (it can heart skin through its
thistles), the second is that milk thistle has potential to become serious weed in arable land.
As a plant from the family Asteraceae has a great anticipation to have vital seeds in soil profile
for long time as well as Helianthus annus L.. On the base of our 4 vegetation periods research, we can
conclude that the S. marianum seeds are vital in soil profile for three and more years. We can also
conclude that in third year after milk thistle cropping was no infestation of durum wheat stands, but S.
marianum plants germinate after the harvest of durum wheat at the stubbles in August or September. On
the base of statistical analyses we concluded that: the very significant highest infestation with S.
marianum was in maize for grain stand in the year 2010. In the spring time the infestation of maize for
grain, pea for grain and durum wheat stands with milk thistle falled very significantly down from 17.78
plant pre m2 in maize stand to 2.56 plant pre m2 in durum wheat stand.
ACKNOWLEDGEMENTS
This paper was supported by VEGA project no. 1/0513/12: „Research of sustainable
agroecosystems for mitigation of climate change, production of bioproducts, improvement of human
nutritional and health parameters“.
Research Journal of Agricultural Science, 44 (2), 2012
122
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... Silybum marianum is an annual and biennial herbaceous broadleaf plant which belongs to family Astraceae [1,2] This herbaceous plant has its origin at Mediterranean and North African areas [3] Silymarin, the active constituent of Silybum marianum plant contains 70-80% silymarin flavonolignans (silybin A and B, isosilybin A and B, silychristin and silydianin and flavonoids, taxifolin and quercetin), and the remaining 20-30% comprising of a chemically uncertain portion that involving oxidized and polymeric polyphenolic mixtures [4] Silybin is considered the main and best effective constituent in silymarin [5] Silymarin keeps an extensive range of pharmacological and biological effects, containing anti apoptotic and antioxidant activity [6,7] It is used as effective antiviral treatment for hepatitis C virus [8] Furthermore, its antidiabetic action [9] cardio protection [10] hypolipidemic, anti-inflammatory, neuroprotective, immune modulation, antifibrotic and neurotropic effects are well recognised [11] It is also beneficial in case of harmful liver injury, liver cirrhosis and chronic inflammatory liver infections [12] It modifies a diversity of cellsignalling pathways, which can be resulting in the decline of pro-inflammatory facilitators [13] It plays significant role in initiation of protein synthesis [2] and regeneration of cell [14]). Anticancer activity is one of the greatest auspicious actions of silybin, furthermore in chemotherapeutics silybin has shown possible use as an adjuvant in the cancerostatic treatment [15] Silymarin has been verified to defend kidney and liver cells from poisonous impacts of drugs containing radiotherapy and chemotherapy [16,17]. Silymarin has been shown among the greatest examined extracts of plant that have identified mechanisms [1] The main cause for the extensive growing or farming of this plant is because of its wide range of effectiveness in treating biliary and liver diseases and inhibiting liver cancer [16] Silybum marianum plants are very violent and modest to agricultural yields, mainly in nutrient-rich places [17] In various kinds of Asteraceae, the productivity of seed propagation and seedling development is very low, unpredictable and is extremely reliant on several biotic and environmental aspects [1,18] Seeds of this plant have flavonolignans (silymarin) in high concentration that are responsible for its beneficial effects against diseases but their yield is very low. ...
... Anticancer activity is one of the greatest auspicious actions of silybin, furthermore in chemotherapeutics silybin has shown possible use as an adjuvant in the cancerostatic treatment [15] Silymarin has been verified to defend kidney and liver cells from poisonous impacts of drugs containing radiotherapy and chemotherapy [16,17]. Silymarin has been shown among the greatest examined extracts of plant that have identified mechanisms [1] The main cause for the extensive growing or farming of this plant is because of its wide range of effectiveness in treating biliary and liver diseases and inhibiting liver cancer [16] Silybum marianum plants are very violent and modest to agricultural yields, mainly in nutrient-rich places [17] In various kinds of Asteraceae, the productivity of seed propagation and seedling development is very low, unpredictable and is extremely reliant on several biotic and environmental aspects [1,18] Seeds of this plant have flavonolignans (silymarin) in high concentration that are responsible for its beneficial effects against diseases but their yield is very low. It has been shown that there are some factors such as information of biosynthesis, passageways of signal transduction, gentle rising flora of various species, random changeability in accumulation of these secondary metabolites and low harvest found in nature which is involved in improving the trials for the source of medicinal values [19] In plant cell culture, with the aim of extensively rise the generation of secondary metabolites numerous plans can be beneficial for instance, enhancing the culture conditions, nourishing of originators and elicitation [20] Silymarin mixtures are commonly extracted from the desiccated fruits of ground developed plants that sometimes need several times such as months to years to be attained compounds. ...
... This process was identical to fields in which plants were producing naturally but that process was time-taking process and prolonged as well. It resembles with soil which was exposed to long time period of saturation of water which correlates with the faulty system of inadequate irrigation and drainage [17]. ...
Enrichment of Therapeutically Significant Flavonolignans of Silybum Marianum in Vegetative Parts by Applying Fungal Elicitors, Methyl Jasmonate and Silver Nanoparticles as Elicitor in Hydroponic Culture
Article
Full-text available
  • Aug 2021
Introduction: Medicinal plants are being used to treat several diseases for many decades and this is an ancient method to treat the patients. Herbal plant Silybum marianum found most effective one to cure liver disorders. This plant produces silymarin which is a secondary metabolite and have hepatoprotective properties. Silymarin is a mixture of flavonolignans (silybin A, silybin B, isosilybin A isosilybin B, silychristin, silydianin apigenin 7-D glucose and taxifolin) that has antiviral, antibacterial, antifungal and antiallergenic properties. Therefore, the excessive production of silymarin is necessary to cure different types liver disorders, so the present study executed to boost up production of Silymarin flavonolignans in vegetative parts of the Silybum marianum plant by using different elicitors. Materials and Methods: In the present study, elicitation technique in hydroponics system was used to enhance the production of pharmacologically active flavonolignans in Silybum marianum. Fungal elicitors prepared from lyophilized Aspergillus niger biomass, methyl jasmonate, silver Original Research Article Mubeen et al.; JPRI, 33(40B): 126-138, 2021; Article no.JPRI.71058 127 nanoparticles and combination of silver nanoparticles and methyl jasmonate were added (0.2g/l), (100µM/l), (1 ppm) and (100µM/lppm) in hydroponics with Hoagland's solution in hydroponics to enhance the production of flavonolignans of Silybum marianum. Controls were also set for each treatment. Plants were harvested after 72 hours of introduction of elicitors. High performance liquid chromatography technique was used for analytical purpose. Four solvents (methanol, acetonitrile, chloroform and 2% Trifloro acetic acid) were used in HPLC. Column was C18 and run time of sample was 1 hour. Silybum marianum's seed extract was used as a standard. Extract of control and treated plants were run on the same polarity in HPLC. Results: Results showed that after elicitation significant increase was observed in production of silymarin's flavonolignans (silybin A, silybin B, isosilybin A, isosilybin B and apigenin 7-D glucose) in vegetative part of the plant but rate of production was different for each elicitor, fungal elicitors prepared from lyophilized Aspergillus niger biomass proved best among all treatments.
... The therapeutic effects of milk thistle are closely connected to the presence of a flavonoid complex called silymarin, composed of a mixture of silybin A and B, isosilybin A and B, silychristin, and silydianin [9,10]. The highest amount of silymarin is present within the achenes (improperly but commonly termed "seeds") of the plant [11][12][13]; however, 3-4 years [39], or even up to 9 years [31]. Hence, plants of S. marianum can be very aggressive and competitive with crops in many cultivated areas, and the species is reported to be a noxious weed [30] on arable land, both in warmer climates (where temperatures rarely fall below 0 °C) [29,40] and in colder regions [41]. ...
... Otherwise, when a second cultivation year of milk thistle is unwelcome, seeds that escaped harvesting represent a source of severe weed infestation for the following crop, and big efforts are usually required for its containment below the damage threshold [29]. In this case, herbicide application on the subsequent crop is considered the most reliable control strategy [39]. Nevertheless, as seedlings and rosettes are more sensitive to selective broadleaf herbicides than older plants [29], herbicide effectiveness depends on S. marianum's developmental stage, and proper timing is crucial for a successful weeding operation. ...
Milk Thistle (Silybum Marianum L.) as a Novel Multipurpose Crop for Agriculture in Marginal Environments: A Review
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Full-text available
  • Mar 2022
Milk thistle (Silybum marianum (L.) Gaertn.) is a versatile crop that has adapted to the broadly different soil and environmental conditions throughout all continents. To date, the fruits (“seeds”) of the plant are the only reliable source of silymarin, which, given its recognized therapeutic effects and its many present and potential uses, has led to a significant re-discovery and enhancement of the crop in recent years. Overall, although many studies have been carried out globally on the bioactivity, phytochemistry, and genetics of milk thistle, few and discontinuous research activity has been conducted on its basic agronomy as well as on the farm opportunities offered by the cultivation of this species. However, the multiple potential uses of the plant and its reduced need for external inputs suggest that milk thistle can perfectly fit among the most interesting alternative crops, even for marginal environments. The growing interest in natural medicine, the increasing popularity of herbal dietary supplements, and the multiple possibilities for livestock feeding are all arguments supporting the idea that in many rural areas, this crop could represent a significant tool for enhancing and stabilizing farm income. However, several issues still have to be addressed. The species retains some morphological and physiological traits belonging to non-domesticated plants, which make the application of some common agronomic practices challenging. Furthermore, the lack of reliable field data devoted to the definition of suitable cropping protocols represents a major constraint on the spread of this crop among farmers. This review has therefore focused on updating information on the main morphological and phytochemical traits of the crop and its agronomic characteristics and novel uses. Several gaps in technical knowledge have been addressed, and further goals for experimental activity have been outlined in order to guide farmers eager to cope with the cultivation of such a challenging and resource-rich crop.
... Milk Thistle is grown commercially as a medicinal plant in Europe, Egypt, China and Argentina (Hammer et al., 1992;Veres et al., 2012). However, milk thistle is considered a weed in sowed annual legume pastures (Sulas et al., 2008), waste areas, cereal crops, decreasing wheat yields (Khan et al., 2009), and along roadsides (Karkanis et al., 2011). ...
Chemical Composition and Biological Activity of Milk Thistle Seeds (Silybum marianum (L.) Gaertn.)
Article
  • Dec 2022
Milk Thistle Seeds (MTS) purifies the liver from all toxic and harmful substances, supports the regeneration of liver cells. In this study, the chemical composition of milk thistle seeds (Silybum marianum (L.) Gaertner = Carduus marianus L.) and also its biological activity were determined. Essential oil was analyzed using by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) techniques. After that, the essential oil was tested against bacteria and fungi by agar well diffusion and micro dilution methods. The essential oil yield was 1.1% (v/w). Eight constituents were comprised the 97.3% of the total oil extract of the Milk thistle seeds. The major compounds were determined as oleic acid (45.6%), linoleic acid (29.0%), ethylbenzene (7.0%) and stearic acid (5.7%). The seed essential oils of MTS significantly inhibited the growth of Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli and Streptococcus sp.) bacteria (p < 0.05). The oils also showed fungicidal activity against Candida tropicalis and C. globrata.
... Given these results, it is not surprising that milk thistle has become a noxious weed in many parts of the world and especially in agricultural ecosystems. Furthermore, its seeds can remain viable in the soil seed bank for up to 3-4 (Vereš & Tyr, 2012) and even 9 years (Sindel, 1991). ...
Variation in seed dormancy and germination among populations of Silybum marianum (Asteraceae)
Article
Milk thistle (Silybum marianum) is a medicinal plant; however, lack of consistency in past dormancy studies has hindered propagation of this species from seeds. We tested the germination responses of freshly harvested and afterripened (stored for 2 and 7 months; 25�C at 50% relative humidity) seeds from three populations (P1, P2 and P3) in Iran at varying constant or alternating temperatures, with or without GA3 and in light and continuous darkness. No germination occurred in freshly harvested seeds incubated at any condition without GA3 application, indicating that all the seeds were dormant. Seeds from P1 and P2, which developed under relatively dry, warm conditions, germinated over a wider range of temperatures after 2 months of dry storage, indicating type 6 of non-deep physiological dormancy (PD). Seeds from P3, which developed under relatively wet, cool conditions, incubated at constant temperatures (especially on GA3), exhibited an increase in maximum temperature for germination, indicating type 1 of non-deep PD. Light improved germination of after-ripened seeds, and GA3 application substituted for the light requirement for germination. This is the first report that environmental conditions during seed development may be correlated with differences in the type of non-deep PD. We conclude that milk thistle seeds are positively photoblastic and photodormant and the germination responses of after-ripened seeds from different populations are different under darkness. Therefore, the impacts of genetic differences and maternal effects on the induction of dormancy during seed development should be considered in attempts to domesticate this medicinal plant.
... Given these results, it is not surprising that milk thistle has become a noxious weed in many parts of the world and especially in agricultural ecosystems. Furthermore, its seeds can remain viable in the soil seed bank for up to 3-4 (Vereš & Tyr, 2012) and even 9 years (Sindel, 1991). ...
Variation in seed dormancy and germination among populations of Silybum marianum (Asteraceae)
Article
  • Apr 2021
Milk thistle (Silybum marianum) is a medicinal plant; however, lack of consistency in past dormancy studies has hindered propagation of this species from seeds. We tested the germination responses of freshly harvested and after‐ripened (stored for 2 and 7 months; 25°C at 50% relative humidity) seeds from three populations (P1, P2 and P3) in Iran at varying constant or alternating temperatures, with or without GA3 and in light and continuous darkness. No germination occurred in freshly harvested seeds incubated at any condition without GA3 application, indicating that all the seeds were dormant. Seeds from P1 and P2, which developed under relatively dry, warm conditions, germinated over a wider range of temperatures after 2 months of dry storage, indicating type 6 of non‐deep physiological dormancy (PD). Seeds from P3, which developed under relatively wet, cool conditions, incubated at constant temperatures (especially on GA3), exhibited an increase in maximum temperature for germination, indicating type 1 of non‐deep PD. Light improved germination of after‐ripened seeds, and GA3 application substituted for the light requirement for germination. This is the first report that environmental conditions during seed development may be correlated with differences in the type of non‐deep PD. We conclude that milk thistle seeds are positively photoblastic and photodormant and the germination responses of after‐ripened seeds from different populations are different under darkness. Therefore, the impacts of genetic differences and maternal effects on the induction of dormancy during seed development should be considered in attempts to domesticate this medicinal plant. This is the first report that environmental conditions during seed development may be correlated with differences in the type of non‐deep physiological dormancy between populations. We conclude that milk thistle seeds are positively photoblastic and photodormant and the germination responses of after‐ripened seeds from different populations are different under darkness.
... Its therapeutic properties are due to the presence of silymarin. The seeds contain the highest amount of silymarin, but the whole organs of plant are used medicinally (Geneva et al., 2008;Veres and Tyr, 2012). ...
Effects of Hydro and Hormonal Seed Priming on Seed Germination of Milk Thistle under Saline Stress Condition
Article
Full-text available
  • Sep 2014
Salinity is an abiotic stress which has harmful effects on germination of many plants. Therefore, high germination rate and vigorous early growth under salty soils is preferred. Seed priming is a way to increase salt tolerance of plants. An experiment was conducted to investigate the effect of seed priming on germination of milk thistle under salinity condition. The treatments were 4 levels of seed priming (no priming, distilled water as hydro priming and 0.5 and 1.0 mM salicylic acid) and 5 levels of salinity (0, 40 and 80 mM NaCl and 40 and 80 mM CaCl2). The experiment arranged as a factorial in a completely randomized design (CRD) with three replications. Results showed that salinity decreased germination percentage and germination rate to about 16 and 32% in 80 mM CaCl2 level compared to control, respectively. The highest mean germination time (5.7 day) were belonged to 80 mM CaCl2. Radicle and plumule length significantly decreased by 80 mM NaCl and 40 and 80 mM CaCl2. The lowest seedling weight and seed stamina observed in 80 mM CaCl2. 0.5 mM salicylic acid improved all traits except mean germination time as compared to control. Salicylic acid (0.5 mM) improved radicle length under 0, 40 and 80 mM NaCl salinity levels as well as increased plumule length at the 0 and 40 mM NaCl salinity conditions.
MORPHOLOGICAL AND CHEMICAL STUDY WITH GEOGRAPHICAL DISTRIBUTION OF SILYMARIN SP. (ASTERACEAE) IN IRAQ
Research
Full-text available
  • Aug 2022
The cultivation of desert plants is widespread in Iraq, especially medicinal plants, some of which are characterized by high temperatures and water stress due to the drought prevailing in these areas. One example of these plants is the milk thistle, known in Iraq as the milk thistle, and in this research paper we will talk about it in detail. In this paper, we will talk in general about the classification of the silymarin sp. plant. Many and varied plants fall under this genus, one of which is Silybum marianum, known as the milk thistle. This plant is considered one of the medicinal herbs that can be used as a medicine to treat some diseases, and it has been used in Iraq as an example of that. Moreover, it aims to study the morphological and chemical as well as the geographical location and places of spread of this plant all in addition to updating the existing evidence on milk thistle extract, which has proven its success in treating various diseases through laboratory, biological and clinical studies, it was found that the silymarin plant contains some active compounds such as flavonolignan and flavonoid taxifolin. Silymarin helps stimulate liver activity and is anti-cancer. It will be clear to us future studies in improving the properties of silymarin plant through genetic breeding.
Pharmacological and Pharmacognosticl Activity of Silybum marianum
Article
  • Sep 2020
Herbs have been utilized for all time as the significant sours of medication. Medical plants are significant by optional metabolites, for example; Silybum marianum, is a remedial herb with a thousand years history of utilization. It is a blend of flavonoids, called silybin, which isn't just the major silymarin component but at the same time is the most dynamic element of this extract, which has been affirmed in different studies. This compound has a place with the flavonoid group known as flavonolignan. Silybin's structure comprises in two fundamental units. The first depends on a taxifolins, the second a phenyllpropanoid unit, which for this situation is conyferil liquor. These two units are connected together into one structure by an oxeran ring contains mixes (taxifolin, silychristin, silydianin, silybinin A and silybinin B. The present study is fundamentally centered on the medicinal important of Silybum marianum, its utility as a medicinal plant for the treatment of different issue of mind, cardiovascular, hepatic, kidney, and oxidative stress also, malignant growth is outstanding. As far as its medicinal properties, Silybum has no symptoms. In any case, it might cause mild nausea or gastrointestinal difficulties in uncommon cases. The leaves, seeds or some of the time the entire plant is utilized inmedicinal preparation.
Milk thistle (Silybum marianum L. Gaertn.) achene yield had a positive response to nitrogen fertilization, row spacing, sowing date, and weed control methods
Article
Knowledge of the response of milk thistle to different levels of agronomic inputs and interactions is essential for the elaboration of the best production technologies. Field trials in a fractional factorial design are helpful in selecting the optimal production technology for plants whose agronomic requirements have not been sufficiently studied under given agroecological conditions. The experiment was set up in a 2n⁻¹ design with a half-replication. It was located on fields of the Agricultural Experiment Station in Bałcyny, Poland, and carried out in the years 2010-2012. The multifactorial experiments conducted under the same climatic and soil conditions helped to determine the optimal intensity of the main agronomic treatments. The experiment was designed to analyze the response of milk thistle to key yield-forming factors (nitrogen fertilization, potassium fertilization, sowing date, row spacing and weed control). The weather conditions during the experiment had a significant impact on most of the assessed parameters. Under the agroecological conditions of north-eastern Poland, a higher nitrogen fertilization dose (80 kg N ha⁻¹) had a significant influence on the yield of milk thistle achenes (an increase of 7.1%), and the yield components improved significantly. An earlier sowing date also resulted in a higher yield of achenes (by 14.9%) and improved the yield structure elements. A positive influence on the yield was also produced by chemical weed control (a significant increase in the yield by 0.15 Mg ha⁻¹ – 12.2%). The spacing between rows and potassium fertilization (100 kg K2O ha⁻¹) applied in milk thistle cultivation did not significantly affect the growth, development plant yield.
MILK THISTLE (SILYBUM MARIANUM): A VALUABLE MEDICINAL PLANT WITH SEVERAL THERAPEUTIC PURPOSES
Article
Full-text available
  • Feb 2020
This review provides a systematic and in-depth overview of the promise and potential of milk thistle (Silybum marianum) as an interesting alternative nutraceutical preparation for pharmaceutical and medicinal applications. Moreover, it aims to summarize and update the existing evidence of extract of milk thistle in the treatment of various diseases by in vitro, in vivo, and clinical studies, and special care is paid to the action mechanisms. The main active component of milk thistle, collectively known as silymarin, consists of a mixture of flavonolignans and flavonoid taxifolin. Silymarin acts as a hepatoprotective, anticancer, anti-inflammatory, immunomodulatory, neuroprotective and lactogenic agent. Precise mechanisms of silymarin action still needs investigations and molecular/genetic background of silymarin synthesis is crucial to be elucidated for reinforcement of the therapeutical potential of the plant by breeding.
Competition and Relative Yield: Estimation and Interpretation at Different Densities and Under Various Nutrient Concentrations Using Silybum Marianum and Cirsium Vulgare
Article
Full-text available
  • Mar 1988
(1) The role of the yield-density relationship in determining the choice of an additive or substitutive experimental design for competition experiments is examined, with particular reference to the design of multispecies experiments. A competition experiment between two thistle species Silybum marianum and Cirsium vulgaris at five density levels and six nutrient concentrations is described. (2) The design allows the influence of density and nutrient concentration on the relative yield in mixture compared with monoculture (RY) of the two species (as estimated from a substitutive design of N/2 plants in mixture) to be examined, and compared with that estimated from an additive design of N plants in mixture, where N is number of plants in monoculture. (3) Yields of the two species in monoculture show similar significant responses to both nutrient concentration and density: maximum yield occurs at a nutrient concentration four times standard Hoagland, and response to density is asymptotic. S. marianum has similar performance in mixture while C. vulgare yields are markedly reduced. Nutrient concentration has a significant influence on the RY of both species. A clear influence of density is only apparent at extremely high nutrient concentrations. (4) Acceptance of an asymptotic yield-density function implies that RY values between 0.5 and 1.0 cannot be interpreted unambiguously as being due to competition in substitutive experiments. Analysis of the substitutive design for S. marianum gives RY between 0.5 and 1.0, which cannot be interpreted as due to competition from C. vulgare. The additive design provides no evidence for such a competitive effect. RY values for C. vulgare are less than 0.5 in both designs indicating a competitive effect by S. marianum. (5) Choice of substitutive or additive design depends on knowledge of the yield-density function. Unequivocal results require a range of density combinations to be included in the design.
Production and quality of milk thistle ( Silybum marianum (L.) Gaertn.) cultivated in cultural conditions of warm agri-climatic macroregion
Article
Full-text available
  • Jun 2009
A polyfactorial field experiment was established and investigated during vegetation periods from 2004 to 2007 at the Dolná Malanta locality (Nitra district, Slovakia). The following parameters were measured: (1) yields of milk thistle (Silybum marianum [L.] Gaertn.) achenes, i.e. fruits, in 2004-2007; (2) content of Silymarin in dry fruits of milk thistle in 2006-2007; and (3) total yields of Silymarin per ha in 2006-2007. Factors of the experiment were as follows: (1) crop residues of cultivated pre-crop (no crop residues - K, with crop residues - R); (2) cultivation of freezing-out intercrop (no intercrop - B, with intercrop - M); (3) fertilization using artificial fertilizers (no fertilization - O, with fertilization - F); (4) year of cultivation (2004-2007). The highest yields of milk thistle fruits were recorded in 2006: from 1,426.5 kg/ha (RBO variant - incorporated crop residues without intercrop, no artificial fertilizers) to 1,832.0 kg/ha (KBF variant - without crop residues, without intercrop and with application of artificial fertilizers). The highest content of Silymarin complex in dry fruits of milk thistle was measured in 2007: from 15.14 mg/kg (RMF - with crop residues, intercrop and fertilization) to 20.01 mg/kg (KBO - without crop residues, intercrop and fertilization). The highest total yield of Silymarin per ha was recorded in investigated variants in 2006; in variant without crop residues it ranged from 16.45 kg/ha (KMF - with intercrop, with fertilizers) to 24.62 kg/ha (KMO - with intercrop, no fertilization).
Milk Thistle (Silybum marianum) Seed Germination
Article
  • Jul 1978
The germination of seeds (achenes) of milk thistle [ Silybum marianum (L.) Gaertn.] was investigated. One month after harvest, milk thistle seeds had afterripening requirements related to germination temperature that limited germination to 10 to 20 C temperatures. The time required to satisfy afterripening requirements was dependent on germination temperature. Generally the higher the incubation temperature during germination, the longer the afterripening requirement (up to a maximum of 5 months). Once afterripening requirements were satisfied, milk thistle seeds germinated over a temperature range of from 0 to 30 C. Optimum germination occurred with 2 to 15 C 16-h cold periods alternating with 10 to 30 C 8-h warm periods. Emergence of milk thistle seedlings decreased with increased burial depth, but substantial emergence occurred from 8 cm. Germination on the surface of the soil or litter was greatly reduced compared to that with slight soil or litter coverage. Potassium nitrate (KNO 3 ) added to the germination substrate at 1.0 mM enhanced the germination of milk thistle seeds at 2 and 5 C incubation temperatures.
Factors affecting the dominance of Silybum marianum L. (Asteraceae) in its specific habitats.
Article
The annual Mediterranean thistle Silybum marianum L. is a synanthropic plant (i.e. related to human habitats) common in Israel. It dominates waste places and ants’ nests, and is disseminated by wind and ants. The purpose of this study has been to find out some of the possible factors during the plant’s life cycle, which may affect its dominance in its specific habitats.
Climatic variation and growth of holy thistle (Silybum Marianum Gaertn.)
Article
There is an increasing interest in weed suppression through manipulation of crop density. To test this hypothesis as to how growth of Holy thistle (Silybum marianum) is affected by environmental conditions, experiment was conducted in RCBD with split plot arrangements by sowing four seed rates of wheat (100, 120, 140 and 160 kg ha-1) in main plots and seven S. marianum densities (0, 3, 6, 9, 12, 15 and 18 m-2) in sub-plots. Increasing seed rate of wheat greatly suppressed the growth of S. marianum during year 1 and had no effect on S. marianum growth in year 2 due to higher rainfall and low temperature which favoured the growth of S. marianum. With the increasing density of either species, the seed production plant-1 of S. marianum decreased but the magnitude of seed reduction was dependent on seed rate, S. marianum density and year effect. Thus seed rate and weed density did not give accurate prediction to estimate the yield losses and competitiveness of weed. Hence other factors like rainfall and temperature should also be considered while developing a model for crop/weed competition. Optimum seed rate (120 kg ha-1) of wheat could contribute to a strategy to reduce yield losses and to prevent this weed from seed production in long-term weed management. However, this approach can be used as a part of integrated weed management.
Cultivation of milk thistle ( Silybum marianum L. Gaertn.), a medicinal weed
Article
Milk thistle (Silybum marianum L. Gaertn.) is the most researched plant for the treatment of liver disease. Its therapeutic properties are due to the presence of silymarin, a mixture of three flavonolignans (silybin, silydianin and silycristin). The seeds contain the highest amount of silymarin, but the whole plant is used medicinally. Milk thistle is grown successfully on a range of soil types, from sandy soils to much heavier clay soils. Milk thistle is directly seeded in soils. Sowing occurs in autumn and spring, and row spacing is usually 40–75cm, with 20–30cm between plants in the row. Nutrient requirements of this crop are low to moderate since it is adapted to poor quality soils and many different growing conditions. A limiting factor in milk thistle production is weed interference. Pendimethalin and metribuzin herbicides are safe for weed control in milk thistle, both alone and in combination. Milk thistle is considered drought resistant and normal rainfall will often suffice. In a Mediterranean environment, under severe drought conditions, the crops should be irrigated during seed growth and filling. Moreover, a few varieties of milk thistle have been developed. The silymarin content most often ranges from 1.0% to 3.0% of achene dry matter but can exceed 8%. Efforts should be made to develop varieties with high silymarin content.
Germination and Phenology of Seven Introduced Thistle Species in Southern Australia
Article
Seeds of seven introduced thistle species, common and widespread in southern Australia, were germi- nated over a range of different day!night temperatures and water potentials. The thistles were Carduus nutans L. (nodding), C. pycnocephalus L. and C. tenuiflorus Curtis (slender), Carthamus lanatus L. (saffron), Cirsium vulgare (Savi) Ten. (spear), Onopordum aff. illyricum (illyrian) and Silybum marianum J. Gaertn. (variegated). Fresh seed of all thistle species germinated over a wide temperature range (15/5° to 40/30°C). Differences between taxa were expressed mainly at low temperatures (15/5° and 15/0°C), at which C. pycnocephalus germinated well and Onopordum only minimally. Germination of C. lanatus seeds was the most sensitive to moisture stress and that of C. nutans and C. vulgare the least. Radicle elongation of germinating seedlings differed at different water potentials, with C. tenuiflorus being the most sensitive to low water potential and that of C. lanatus the least, even at a water potential of - 1.5 MPa. The seven thistle species were separated into three groups based on the patterns of their phenological responses over two seasons when grown in a common environment. Carduus pycnocephalus and C. tenuiflorus behaved as short-season annuals, C. vulgare and Onopordum showed a strongly biennial response, and the other species were annual except for C. nutans, which behaved as an annual or a biennial depending on time of establishment. We conclude that the differences in germination responses to temperature and water potential between the different introduced thistles are minor. In combination with the major differences in phe- nology revealed in this study some of these differences may help to explain the predominance of the seven thistles in different regions of southern Australia. Other factors will largely determine their weediness in any one region.
Biology of milk thistle (Silybum marianum) and the management options for growers in north‐western Pakistan
Article
Milk thistle (Silybum marianum) is cultivated as a medicinal plant but it also can be a troublesome weed. It is an annual or biennial herb that prefers high rainfall and fertile soils. Milk thistle has become a widespread weed in north-western Pakistan, where it causes yield reductions ≤37% in wheat and poses harvesting problems due to its thorny nature. Shortcomings in cultural practises, such as a low crop seed rate, wide row spacing, broadcast fertilizer, and limited crop rotation have contributed to milk thistle becoming a severe weed problem for farmers in this region. This paper reviews the biology of milk thistle and discusses the possible management options for its control, considering the socioeconomic conditions of farmers in Pakistan.
First Report of Silybum marianum as a Host of Puccinia punctiformis
Article
Silybum marianum (L.) Gaertn. (milk thistle) is a problematic invasive weed in the western United States. The rust fungus, Puccinia punctiformis (F. Strauss) Rohl., is found throughout the world as a pathogen of Cirsium arvense (L.) Scop. (Canadian thistle). Recently, plants of S. marianum grown from surface-disinfested seeds in our quarantine greenhouse were parasitized by a rust. Apparently, an isolate of P. punctiformis collected from C. arvense in Turkey that was present in the greenhouse had spread to adjacent S. marianum plants and caused infection without applying any artificial dew period. Ribosomal internal transcribed spacer region sequences from fungal spore DNA isolated from the two hosts were identical. Initial signs on S. marianum were abundant, fragrant spermogonia on large leaves. These signs occur on secondary shoots of C. arvense and are indicative of systemic fungal infection (1). As the fungus infection developed on S. marianum, uredinia and urediniospores were produced. Sori on older leaves also produced teliospores. Urediniospores from infected leaves were harvested and sprayed uniformly on eight 17-day-old plants of S. marianum grown in isolation from P. punctiformis. The spore suspension consisted of 4 mg urediniospores suspended in 40 ml distilled water. Inoculated plants were incubated for 18 h in a dew chamber at 20°C in the dark and transferred to a greenhouse (20 to 25°C, 30 to 50% relative humidity, and natural light). After 13 days, uredia with urediniospores developed on four of the plants. Using the same procedure, inoculations were repeated on plants of S. marianum and S. eburneum Coss. & Durieu (the only other species described in the genus) with urediniospores of a domestic isolate of the fungus from C. arvense in Maryland. Of 51 inoculated plants of S. marianum, 23 became infected and produced uredinia. None of the 12 inoculated plants of S. eburneum showed symptoms of infection. In nature, C. arvense and S. marianum occupy different ecological areas. C. arvense is found predominately in humid temperate habitats, while S. marianum is found in habitats with a dry Mediterranean climate. Life cycles of each host are also different. C. arvense is a perennial that emerges in spring and dies back in winter, while S. marianum is a winter annual that emerges in fall and dies in late spring. Because of the differences in life cycles combined with the different geographical distribution, P. punctiformis from C. arvense may rarely encounter susceptible S. marianum plants in the field. Since fungal spores can be produced routinely on artificially inoculated plants, there might be potential to use P. punctiformis for biological control of S. marianum. To our knowledge, this is the first report of S. marianum as a host for P. punctiformis. Reference: (1) A. H. R. Buller. Puccinia sauveolens and its sexual process. Page 345 in: Researches on Fungi. Vol VII. The Sexual Process in the Uredinales, Toronto, Canada, 1950.