THE EFFECT OF LYOPHILIZED SOIL EXTRACTS O N GERMINATION, LENGTH OF HYPOCOTYL AND ROOT OF TRIFOLIUM-PRATENSE, CV VESNA AND FESTUCA-ARUNDINACEA, CV KORA

Allelopathic action of extracts from soil samples from grasslands take n from eight perennial grass species (trial A) and from band reseeding into grassland (four depths) in four dates (trial B) was studied as a ffected the energy of germination capacity, length of hypocotyl and ro ots of Trifolium pratense, cv. Vesna and Festuca arundinacea, cv. Kora . Soil samples with above-ground biomass (stubble of the 100 mm height ) were taken, extracted with distilled water, lyophilized and subseque ntly diluted to three concentrations of calculated weight moisture of soil according to M-RL=a.W-hmI.M-PVL/a.W-hm+M-v.(M-srel+W-hm). Testing of soil samples was conducted by the method after Pederson the formul a (1986). Water extracts from soil samples of grasses inhibited statis tically highly significantly the root length, less the energy of germi nation capacity and length of hypocotyl. Inhibition of the root length of Trifolium pratense, cv. Vesna (Fig. 1) was falling in the order Ar rhenatherum elatius, Bromus inermis, generic hybrid H (Z) over cap-5-D K, Festuca arundinacea, Alopecurus pratensis, Paa pratensis, Dactylis glomerata, Phalaris arundinacea; inhibition of root length is statisti cally highly significant in all grass species compared with the contro l with the distilled water, only in Phalaris arundinacea the inhibitio n is statistically significant. The hypocotyl length of Trifolium prat ense, cv. Vesna inhibited extracts in the following order: Bromus iner mis > Festuca arundinacea > Arrhenatherum elatius > Dactylis glomerata compared with distilled water and they stimulated in the order: Poa p ratensis < Alopecurus pratensis < generic hybrid H (Z) over cap-5-DK < Phalaris arundinacea; decrease in the length of hypocotyl against con trol with distilled water is highly significant in Bromus inermis and increase is highly significant in Phalaris arundinacea. Energy of germ ination was inhibited in descending order Bromus inermis > Festuca aru ndinacea > Arrhentherum elatius > Dactylis glomerata > Poa pratensis < Phalaris arundinacea > generic hybrid H (Z) over cap-5-DK > Alopecuru s pratensis, whereas decrease of energy of germination capacity in Bro mus inermis and Festuca arundinacea is statistically highly significan t against control (distilled water). Tn the experiment A statistically highly significant inhibitory action of concentration of soil extract s on average of grass species on energy of germination, length of hypo cotyl and roots of Trifolium pratense, cv. Vesna at increasing concent ration of soil extract (Fig. 2) was found. Soil extracts from differen t depths of sampling in the experiment B (Fig. 6) inhibited the length of roots- of Trifolium pratense (statistically highly significantly) in all depths compared with distilled water; length of roots of Festuc a arundinacea was strongly stimulated, that is again statistically hig hly significantly compared with distilled water. Extracts from soil sa mples taken band reseeding into grassland on four dates of reseeding ( Fig. 9) demonstrated highly significantly action on the length of root s and length of hypocotyl among different dates in both tested species . The results obtained showed that in the grassland ecosystem are comp rised specifically active substances which can stimulate or inhibit in itial growth and development of introduced species in dependence on th e concentration of substances comprised in soil solution. Allelopathic action is a significant regulatory mechanism of technology of additio nal seeding into grasslands.