Lepidium sativum, seed germination

Cress (Lepidium sativum) and radish (Raphanus sativus) are small seeds, quick to germinate and sensitive to phytotoxic (plant damaging) substances like the organic acids temporarily present in immature composts. 

The general procedure for seedling bioassay was as follows 25 seeds of each species were placed per dish, excepting Hordeum vulgare (10 seeds per dish), with 5 mL of the test solution, and incubated in the dark at 25°C. Four replicates for each concentration were set up. Germination and growth time varied for each plant species Lepidium sativum, 3 days Lactuca sativa and Hordeum vulgare, 5 days and Allium cepa, 7 days. 

Crude extracts, fractions, or pure compounds are dissolve in an appropriate solvent, then serially diluted to obtain the desired concentration. Solutions are filter sterilized prior to bioassay. In a glass petri dish, a known quantity of test solutions are applied onto a filter paper (Whatman No. 1) and allowed to evaporate to dryness. To each petri dish, 10-15 seeds of the test species are added followed by deionized Water (1.5 ml). For example, curley cress (Lepidium sativum L.)is used as an example for a broad leaf species. Negative controls consist of an equal amounts of evaporated solvent and deionized H2O. All treatments are replicated thrice. Petri dishes are then covered, randomized, and placed in a humid chamber for 72 h at 26°C. Thereafter, root lengths are measured and an I50 (50% germination or growth inhibition) level is determined for each of the treatments. Data are subjected to ANOVA and means are compared by an LSD test [92]. 

C22H28O6, Mr 388.46, square prisms, mp. 196-197 °C. G., a very bitter-tasting diterpene of the 4a,5/S- cler-odane type from the liverwort Gymnocolea inflata, shows a number of biological activities Thus anti-feedant effects on larvae of Japanese Pieris species, inhibition of root growth (10 -10 Mol) in the cress (Lepidium sativum), and promotion of germination (10 -10" Mol) of wheat seeds have been reported. Ut. J. Hattori Bot. Lab. 39,215 (1975). Zinsmeister Mues (eds.), Bryophytes, their Chemistry and Chemotaxonomy (Proc. Phytochem. Soc. Eur. 29), p. 399,404, Oxford Clarendon Press 1990. 

Fig. 4.4. The ultimate percentage germination of seeds of Lepidium sativum and Agros-temma githago on sintered glass plates at controlled moisture tensions with (—and without (---) added mucilage. Plant mucilage obtained from seeds of Plantago psyllium and called Coreine was used. After Harper and Benton, 1966 [25]...

Buss, W., Masek, O., 2014. Mobile organic compounds in biochar — a potential source of contamination — phytotoxic effects on cress seed (Lepidium sativum) germination. Journal of Environmental Management 137, 111—119. http //dx.doi.0rg/lO.lOl6/j.jenvman. 2014.01.045. 

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