biologia plantarum

Biologia plantarum 37:423-428, 1995 | DOI: 10.1007/BF02913992

Changes in glucose-6-phosphate dehydrogenase and ribonucleases activities during PVY-RNA biosynthesis in infected potato plants

L. Burketová¹

¹ Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Praha 6, Czech Republic

Changes in glucose-6-phosphate dehydrogenase, ribonucleases activities and chlorophyll content were studied in leaves of plants systemically infected by potato virus Y, necrotic strain (PVY^N). Potato cultivars Jara and Adretta differing in resistance to potato virus Y were used. No statistically significant differences were observed between healthy and infected plants of both cultivars in chlorophyll content. Activity of glucose-6-phosphate dehydrogenase slowly increased in connection with virus multiplication and reached 203.4% of the values of non-infected control in susceptible cv. Jara and 160.4% in the resistant cv. Adretta. Differences between cultivars were significant from 60 d after inoculation (P≤0.05). The activity of ribonucleases quickly increased in the initial period of the experiment and then slowly decreased. Their activities reached 195.6% in susceptible cultivar and 183.5% in the resistant one. Significant differences (P≤0.01) between susceptible and resistant cultivars was found from 18 to 35 d after inoculation. The activities of enzymes corresponded to PVY^N multiplication which was since 40 d considerably higher (P<0.01) in susceptible cultivar in comparison with the resistant one. Thus the activities of studied enzymes could be considered as markers of resistance of potato cultivars to PVY^N multiplication.

Keywords: chlorophyll; potato virus Y; Solanum tuberosum

Received: September 30, 1994; Accepted: March 20, 1995; Published: September 1, 1995  Show citation