| Abstract:In the pot experiment, the Brassica oleracea was used as rootstock and the Nasturtium officinale was used as the scion to study the physiological characteristics and selenium absorption of the N.officinale cuttings after the first grafting, second grafting and third grafting under the condition of soil selenium content of 10 mg/kg. The results showed that multiple grafting was beneficial to the biomass and soluble sugar content of the N.officinale cuttings, the biomass of roots, stems and leaves of the N.officinale increased by 266.84%, 256.49%, 174.03% compared with control. Compared with the self-rooted seedlings of N.officinale, different number of grafting significantly increased the chlorophyll a, chlorophyll b and carotenoid content of the N.officinale cuttings, while the chlorophyll a/b was reduced. In addition, the CAT activity of the N.officinale cuttings increased with the increase of the number of grafting, while the SOD activity, POD activity and malondialdehyde content all showed a downward trend. As far as the selenium absorption characteristics of the N.officinale cuttings, the first, second and third grafting significantly increased the selenium content of the roots in N.officinale cuttings, and increased by 7.05%, 6.84% and 6.47% compared with control, respectively. However, the selenium content of the shoots in N.officinale cuttings and transport factor decreased with the increase of grafting number, which inhibited the transfer of selenium to shoots to some extent. Never the less, because grafting significantly promoted the accumulation of dry matter in N.officinale, the accumulation of selenium in all parts of the N.officinale cuttings was significantly higher than that of control, and increased with the increase of grafting number. Among them, the third grafting resulted in the maximum selenium accumulation in the roots and shoots of N.officinale cuttings and increased selenium accumulation by 290.44% and 110.08% respectively compared with the control, which was beneficial to the accumulation of selenium of the N.officinale cuttings. |
