VARIETY RESPONSE TO DIRECT GERMINATION OF STENOSPERMIC SEEDS CLASSIFIED ACCORDING TO THE HARDNESS OF THEIR SEED COATS

J.G. Valdez, M.A. Andreoni, P. Castro, S.M. Ulanovsky
In plant breeding programs for table grapes the embryo rescue technique is used to improve the seedless percentage in F1. Embryo excision is a time consuming and delicate task, instead direct germination (DG) is a good alternative. Embryos were excised after 100 d and 400 d of in ovulo culture. The number of embryos germinating directly was recorded. Cross breeding was classified according to the hardness of the mother seed coats. A significant influence of the pollen source was observed in all cases except when seminal traces of Superior crosses were dissected for embryos at 100 d. There were no embryos in the soft seed coat group at 400 d, but the numbers of them obtained in the hard seed coat group were significant. In Superior seedless it was observed that the number of embryos obtained by excision at 100 d was higher than the number of total plantlets obtained at 400 d. The observed in vitro abortion could be explained by tissue exudates. It is necessary to perform embryo excision in varieties with hard seed coats, given that these seem to resist mechanical germination. Varietal characterization from the response of open pollinated seminal traces when they are cultivated in vitro, should be taken cautiously because of the influence of the pollinator.
Valdez, J.G., Andreoni, M.A., Castro, P. and Ulanovsky, S.M. (2000). VARIETY RESPONSE TO DIRECT GERMINATION OF STENOSPERMIC SEEDS CLASSIFIED ACCORDING TO THE HARDNESS OF THEIR SEED COATS. Acta Hortic. 528, 659-662
DOI: 10.17660/ActaHortic.2000.528.98
https://doi.org/10.17660/ActaHortic.2000.528.98
Vitis vinifera L., embryo rescue, direct germination, seed coat resistance, pollen influence, toxic exudates

Acta Horticulturae