Sericea lespedeza

Figure 12. -NMR spectrum of the haustorial inducer from Lespedeza sericea.

Seeds of Lespedeza sericea were surface sterilized by soaking in Captan (1 g/1) 1 h, 35% Clorox for 20 min, and washing with IN HCI and water. For quantitation of components in Lespedeza roots, seeds were sown on moistened filter paper in plastic Petri dishes. 

Table II. Root Exudate and Extract Quantitation Lespedeza sericea...

The haustoria of the parasites do not form when the plants are grown axenically, but are rapidly induced in the presence of the host roots or host root exudates (17). Several haustorial-inducing compounds have now been characterized. Xenognosin A and B were identified in gum tragacanth, an exudate of Astragalus gummifer. and soyasapogenol B was identified in roots of Lespedeza sericea. 

The haustorial inducer from Lespedeza sericea for the parasite Agalinis purpurea, however, proved to be a triterpene, soyasapogenol B (Lynn, 1985). 

Scrophulariaceae) approach those of the host, Lespedeza sericea, soyasapogenol B (74) induces haustorial formation (Fig. 23.27) (Lynn, 1985). 

Lespedeza sericea 53rd Ann. Rep. S> Carol. Exp. Sta., Clemson Agric. College, p. 71. 

Fig. 2.42. a Long-range COSY spectrum of derivative 41 from hausterium-inducing component (40), isolated from Lespedeza sericea showing four-bound coupling from H-21 (eq) to 3O-CH3 and H-19 (eq), utilizing a delay A = 0.02 sec b COSY spectrum without delay, A - 0.0 (363)... 

Labcratory rat / Sericea lespedesa tannin extract (Lespedeza cuneata Leguminosae [AD]). (26)... 

Sheep / Varieties of Sericea lespedeza (Lespedeza cuneata leguminosae [P]). (29)... 

For convenience, (+)-catechin rather than purified procyanidins is used to standardize the assay, although this leads to a considerable overestimation. For example, the use of (+)-catechin instead of purified proanthocyanidins as a standard for the analysis of Sericea lespedeza forage crop approximately doubled proanthocyanidin estimations in the samples [52]. 

Aerial portions contained more extractable inhibitory substances than did the roots. Seed germination of tall fescue, ball clover, sericea (Lespedeza cwneflW (Dumond) G. Don) and Kobe lespedeza Lespedeza striata (Thumb) H. and A.) were inhibited by extracts of pepperweed. The toxic substance(s) was present in all parts of the plant, and was toxic to crownvetch at a concentration of 1 150. The extracts were also toxic to five species of fungi. When pepperweed residues were mixed with soil there was no effect on seed germination, but seedling growth was retarded. The authors were of the opinion that the toxicity of pepperweed may be of significance in its competition with other plant species. 

Donnelly, E.D., and Anthony, W.B., 1969, Relationship of tannin dry matter digestibility and crude protein in Sericea lespedeza Crop Sci., 9 361. 

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