Published in Scientific Papers. Series B, Horticulture, Vol. LXIV, Issue 2
Written by Stanislav BOJIMIROV, Tzvetan KIKINDONOV, Ahmed MEHMED
In the conditions of Bulgaria stevia multiplies by storage of the rhizomes and obtainment of seedlings of cuttings and from in vitro maintained clones. Seeds are obtained episodically in conditions of short day at the end of vegetation with a warm and continuous autumn. Aiming art gene fund enrichment, in 2018-2019 are harvested seeds by gathering and cleaning of tied seeds from selected plants of the Selection Field of Agricultural Institute - Shumen. For the seeds progenies in laboratory conditions the germination energy on the 4th day reaches up to 46%. On the seventh day the mean germination increases to 40.9%. In a soil mixture the average value for the seventh day falls back insignificantly to that in laboratory conditions, and the variation between the origins is significantly higher. On the 14-th day the germination reaches mean of 47.5%, as for separate genotypes it exceeds 75%. The results of the seeds obtained from regenerants show a decrease of the mean values of germination to 36.2%in laboratory, and to 31.1% - in external conditions. A bigger variation is registered in the germination energy in laboratory conditions. The one year storage of the seeds decreases the germination to the average of 15.8%. It is impressive the influence of the genotype for the germination preservation, the variation increases to 52.1%, and the lack of significant correlation between the germination before and after storage.
[Read full article] [Citation]