Milk Thistle(Silybum marianum)Seed Germination

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 (KNO3) added to the germination substrate at 1.0 mM enhanced the germination of milk thistle seeds at 2 and 5 C incubation temperatures.

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Seed germination of Solanum spp. (Solanaceae) for use in rehabilitation and commercial industries

Australian Journal of Botany ◽

10.1071/bt07209 ◽

2008 ◽

Vol 56 (4) ◽

pp. 333 ◽

Cited By ~ 20

Author(s):

L. E. Commander ◽

D. J. Merritt ◽

D. P. Rokich ◽

G. R. Flematti ◽

K. W. Dixon

Keyword(s):

Seed Germination ◽

Food Industry ◽

Incubation Temperature ◽

Solanum Species ◽

Seed Embryo ◽

Physiological Dormancy ◽

Incubation Temperatures ◽

Smoke Water ◽

Solanum Spp ◽

Seeds Germination

Effective methods for propagation of native Solanum species are required for mine rehabilitation and the native food industry in Australia. This study investigated seed germination of eight native Solanum species with respect to incubation temperature and the efficacy of germination-promoting compounds gibberellic acid (GA3), the butenolide isolated from smoke (karrikinolide, KAR1) and smoke water (SW). Seeds of all species were tested under a temperature regime of 26/13°C or 33/18°C. In these conditions, seeds of only two species, S. cunninghamii Benth. and S. phlomoides Benth. germinated to high levels without treatment. Of the remaining six species, GA3 alone promoted germination in S. chippendalei Symon, S. diversiflorum F.Muell. and S. sturtianum F.Muell., whereas GA3, KAR1 and SW were effective at promoting germination of S. centrale J.M.Black, S. dioicum W.Fitzg. and S. orbiculatum Dunal ex Poir. to varying degrees. Additional incubation temperatures (10, 15, 20, 25 and 30°C) were examined for S. centrale and S. orbiculatum. For both species, broadly similar patterns were noted in the response of seeds to GA3, KAR1 and SW across all temperatures. However, for S. centrale seeds, germination percentages were higher at 26/13°C than at any of the constant temperatures, and there was a trend of increasing germination with increasing constant temperature for S. orbiculatum seeds. Analysis of seed embryo type and imbibition characteristics and consideration of the subsequent germination results indicates that dormant Solanum seeds possess physiological dormancy.

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Evaluation of milk thistle (Silybum marianum (L.) Gaertn.) seed germination in relation to seed health and seedling emergence

Herba Polonica ◽

10.2478/hepo-2018-0013 ◽

2018 ◽

Vol 64 (3) ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Agnieszka Rosińska ◽

Hanna Dorna ◽

Dorota Szopińska ◽

Lidia Irzykowska ◽

Katarzyna Seidler-Łożykowska

Keyword(s):

Seed Germination ◽

Seedling Emergence ◽

Correlation Coefficients ◽

Milk Thistle ◽

Silybum Marianum ◽

Seed Health ◽

Plant Emergence ◽

Blotter Paper ◽

Positive Correlations ◽

Method Of Evaluation

Summary Introduction: : Milk thistle (Silybum marianum (L.) Gaertn.) is an important medicinal plant. Achenes of milk thistle contain sylimarin, protecting liver cells against toxic compounds. Objective: The aim of the research was to find an optimum method of evaluation of milk thistle seed germination. Methods: Ten seed samples were tested. The seeds were germinated: on top of blotter paper, on top of blotter paper after seed disinfection, between pleated blotter paper, in rolled blotter paper and in sand. Germination at the first and final counts, the percentages of abnormal seedlings and dead seeds were determined. The correlation coefficients between seed germination, evaluated with various methods, and seedling emergence were calculated. Moreover, fungi associated with seeds and diseased seedlings were identified. Results: The lowest percentage of normal seedlings was observed after germination on the top of blotter. Highly significant positive correlations were noted between seedling emergence and seed germination at the final count evaluated in rolled paper, between pleated paper and in sand. The fungi from genera: Alternaria, Fusarium, Penicillium, Trichoderma, Ulocladium and Verticillium were frequently identified on seeds and seedlings. Conclusions: Infestation with fungi significantly affected milk thistle seed germination and plant emergence. Germination in rolled blotter paper may be recommended for evaluation of milk thistle seed germination, as the most practical and significantly correlated with seedling emergence.

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Initial Egg Weight, Time to Maximum Alevin Wet Weight, and Optimal Ponding Times for Chinook Salmon (Oncorhynchus tshawytscha)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f85-036 ◽

1985 ◽

Vol 42 (2) ◽

pp. 287-291 ◽

Cited By ~ 38

Author(s):

Peter J. Rombough

Keyword(s):

British Columbia ◽

Chinook Salmon ◽

Oncorhynchus Tshawytscha ◽

Incubation Temperature ◽

Egg Weight ◽

Size Groups ◽

Wet Weight ◽

Time Required ◽

Incubation Temperatures ◽

Best Fit

Eggs of chinook salmon (Oncorhynchus tshawytscha) were segregated into eight size groups (range 163–437 mg) and incubated at 5, 7.5, 10, and 12.5 °C. The time required to reach maximum alevin wet weight (MAWW) varied significantly (p < 0.01) both with mean incubation temperature (T °C) and with initial egg weight (W mg). A good (R2 = 98.4%, n = 21) prediction of days postfertilization to MAWW (D) is given by[Formula: see text]Optimal ponding times are closely associated with the attainment of MAWW and can be estimated using this equation. Data relating mean incubation temperatures (T) to actual ponding time were collected from 17 hatcheries throughout British Columbia. The equation[Formula: see text]where D′ is days postfertilization to ponding, provided the best fit to the data (R2 = 97.5%, n = 85). Hatchery ponding times were not significantly different from times to MAWW predicted for 200-mg eggs.

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Non-Deep Simple Morphophysiological Dormancy and Germination Characteristics of Gentiana triflora var. japonica (Kusn.) H. Hara (Gentianaceae), a Rare Perennial Herb in Korea

Plants ◽

10.3390/plants10101979 ◽

2021 ◽

Vol 10 (10) ◽

pp. 1979

Author(s):

Hyeon-Min Kim ◽

Jun-Hyeok Kim ◽

Da-Hyun Lee ◽

Young-Ho Jung ◽

Chung-Youl Park ◽

...

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Incubation Temperature ◽

Potassium Nitrate ◽

Perennial Herb ◽

Cold Stratification ◽

Gentiana Triflora ◽

Nitrate Treatment ◽

Morphophysiological Dormancy ◽

Seed Propagation

This study investigated the kind of seed dormancy and seed germination of Gentiana triflora var. japonica (Kusn.) H. Hara for developing a seed propagation method. The seeds were collected in October 2020 from plants at Mt. Sobaeksan, Korea. In a water imbibition experiment, seed weights increased by > 101.9% of their initial masses over 12 h. Effects of incubation temperature (5, 15, 20, 25, 15/6, or 25/15 °C), cold stratification period (5 °C; 0, 4, 8, or 12 weeks), and gibberellic acid (GA3; 0, 10, 100, or 1000 mg∙L−1) and potassium nitrate treatment (KNO3; 0, 1000, 2000, or 4000 mg∙L−1) on seed germination were investigated to characterize seed dormancy. These seeds exhibited underdeveloped embryos during seed dispersal. The seeds failed to reach the final germination of 15.0% after treatment at 5, 15, 20, 25, 15/6, or 25/15 °C. After cold stratification for 8 weeks, the germination increased dramatically by > 90.0% compared to that at 0 weeks. After the GA3 treatment, the germination reached > 80.0% within 5 days. The final germination was 90.0% in the 100 mg∙L−1 GA3 treatment group. However, the KNO3 treatment had no effect on seed germination. Therefore, the G. triflora var. japonica seeds exhibited non-deep simple morphophysiological dormancy.

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Effect of Chitosan on Seed Germination and Biochemical Traits of Milk Thistle (Silybum marianum) Seedling under Salt Stress

Iranian Journal of Seed Research ◽

10.29252/yujs.3.2.105 ◽

2017 ◽

Vol 3 (2) ◽

pp. 105-118

Author(s):

Mehdi Aghighi Shahverdi ◽

Heshmat Omidi ◽

Sayed Esmail Mousavi

Keyword(s):

Salt Stress ◽

Seed Germination ◽

Milk Thistle ◽

Silybum Marianum ◽

Biochemical Traits

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Geographical variation in seed germination and biochemical response of milk thistle (Silybum marianum) ecotypes exposed to osmotic and salinity stresses

Industrial Crops and Products ◽

10.1016/j.indcrop.2020.112507 ◽

2020 ◽

Vol 152 ◽

pp. 112507

Author(s):

Hossein Hammami ◽

Bijan Saadatian ◽

Seied Amir Hossein Hosseini

Keyword(s):

Seed Germination ◽

Geographical Variation ◽

Biochemical Response ◽

Milk Thistle ◽

Silybum Marianum

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A hydrothermal time model of seed after-ripening in Bromus tectorum L.

Seed Science Research ◽

10.1017/s0960258500003214 ◽

1996 ◽

Vol 6 (4) ◽

pp. 155-164 ◽

Cited By ~ 66

Author(s):

Maren Christensen ◽

Susan E. Meyer ◽

Phil S. Allen

Keyword(s):

Seed Germination ◽

Water Potential ◽

Time Course ◽

Bromus Tectorum ◽

Incubation Temperature ◽

Hydrothermal Time ◽

Germination Time ◽

Water Potentials ◽

Incubation Temperatures ◽

Base Water Potential

AbstractBromus tectorum L. is an invasive winter annual grass with seeds that lose dormancy through the process of dry after-ripening. This paper proposes a model for after-ripening of B. tectorum seeds based on the concept of hydrothermal time. Seed germination time course curves are modelled using five parameters: a hydrothermal time constant, the fraction of viable seeds in the population, base temperature, mean base water potential and the standard deviation of base water potentials in the population. It is considered that only mean base water potential varies as a function of storage duration and incubation temperature following after-ripening. All other parameters are held constant throughout after-ripening and at all incubation temperatures. Data for model development are from seed germination studies carried out at four water potentials (0, −0.5, −1.0 and −1.5 MPa) at each of two constant incubation temperatures (15 and 25°C) following different storage intervals including recently harvested, partially after-ripened (stored for 4, 9 or 16 weeks at 20°C) and fully after-ripened (stored for 14 weeks at 40°C). The model was fitted using a repeated probit regression method, and for the two seed populations studied gave R2 values of 0.898 and 0.829. Germination time course curves predicted by the model generally had a good fit when compared with observed curves at the incubation temperature/water potential treatment combinations for different after-ripening intervals. Changes in germination time course curves during after-ripening of B. tectorum can largely be explained by decreases in the mean base water potential. The simplicity and good fit of the model give it considerable potential for extension to simulation of after-ripening under field conditions.

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Effects of stratification, temperature, and oxygen on woolly cupgrass (Eriochloa villosa) seed dormancy

Weed Science ◽

10.1017/s0043174500091037 ◽

1998 ◽

Vol 46 (5) ◽

pp. 526-529 ◽

Cited By ~ 12

Author(s):

Iliya A. Bello ◽

Harlene Hatterman-Valenti ◽

Micheal D. K. Owen

Keyword(s):

Seed Germination ◽

Oxygen Concentration ◽

Seed Dormancy ◽

Field Experiments ◽

Soil Surface ◽

Burial Depth ◽

Low Oxygen ◽

Germination Temperature ◽

Woolly Cupgrass ◽

Eriochloa Villosa

Laboratory and field experiments were conducted to determine the effects of temperature, oxygen, and seed burial depth on woolly cupgrass seed dormancy. Woolly cupgrass seeds at physiological maturity are innately dormant. Stratifying these seeds at 5 C for 8 wk increased germination to greater than 90%, regardless of the germination temperature. Alternating the germination temperature hastened germination by 2 wk, while seedcoat removal hastened germination by another 4 wk. Low oxygen concentration was more detrimental to seed germination when seeds were subjected to constant temperatures in comparison to alternating temperatures. Oxygen concentration did not affect seed germination when seeds were placed in an alternating 15/25 C regime. Seed germination was approximately 15% less when seeds were stratified for 2 wk and subjected to oxygen concentrations below the ambient oxygen concentration, whereas this decrease was present only at the 8% oxygen concentration when seeds were stratified 4 wk. In the field, the stratification requirement was satisfied by early December for the study year. Seeds remaining on the soil surface overcame dormancy sooner than seeds buried 2 or 4 cm.

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