Application of electron and X-radiation of nano- and subnanosecond duration in sea buckthorn breeding

 

Pavlovskaya E.M., Pavlovskaya N.G., Loyko T.V., Nedoykash Ju.M., Russian Nuclear Center, Russia
Fefelov V.A., Kuznetsova T.N., Selekhov V.V., Nizhny Novgorod State Agricultural Academy, Russia

The actual problem of genetic work and breeding now is the search for new inductors of variability that would increase outcomes of experimental mutagenesis.

In the Russian Nuclear Center there have been developed small megavolt pulsing accelerators generated electron and X-radiation with pulse duration of 10 8 10 10 sec and dose power of 10 8 10 12 Gr/sec. Such a short duration is similar to relaxation time of the ions appeared after irradiation. Since molecular reactions take nanosecond intervals of time (about 10 9 sec) we consider those inductors to have perspectives in creation new genetically enriched initial material for selection.

Objects of investigation were sea buckthorn pollen, seeds and sprouts. Pollen was irradiated with the doses of 10, 25, 40, 55, 70 kRad. Stimulated effect on pollen fertility was revealed in the variants with the dose of 25 kRad. There was observed certain dependence: the higher dose was applied the shorter pollen tubes were formed at germination. Probably it s connected with the deviation in the tube synthesis. Irradiation doesn t affect number of filled pollen grains. Noticed higher viability of pollen with increased content of starch.

In some variants irradiated pollen has stimulated effect on fruit setting versus controls (with non-radiated pollen) but later yield reduction was more there and number of mature fruits appeared less then in control variants.

Irradiated pollen significantly affects biochemical composition of sea buckthorn fruits. Along with rising of the dose the content of sugar increases but fat and vitamin C content falls. Maximal fat content was at 40 kRad. There were intervarietal differences observed.

Sea buckthorn seeds were exposed to radiation from 40 to 280 kRad of power. The doses above 120 kRad decrease germination, energy and simultaneity of sprouting. Even irradiated with the dose of 280 kRad some seeds normally germinated.Titel des Vortrages: New sea buckthorn cultivars for Northern conditions