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Acetylsalicylic acid (aspirin) induces resistance to tobacco mosaic virus in tobacco
VIROLOGY
99, 410-412
(1979)
SHORT COMMUNICATIONS Acetylsalicylic
Acid (Aspirin) Induces Resistance Virus in Tobacco
to Tobacco
Mosaic
R. F. WHITE Rothamsted
Experimental Station, Harpenden,
Hertfordshire
AL,5 ZJQ, England
Accepted August 23, 1979
Tobacco cv. Xanthi-nc becomes resistant to tobacco mosaic virus (TMV) and produces b proteins when injected with the interferon inducer polyacrylic acid. Injection of acetylsalicylic acid (aspirin), benzoic acid, or salicylic acid also induces this response in Xanthi-nc. Injection of aspirin, benzoic acid, or salicylic acid similarly induces resistance and the formation of new proteins in the White Burley and Samsun NN cultivars of tobacco.
Tobacco, Nicotiana tabacum cv. Xanthinc, becomes completely resistant to infection with TMV 2-3 days after injecting the leaves with a 50 pg/ml solution of polyacrylic acid, molecular weight 3500 (1). Three new proteins (b,-b,) appear in the injected leaves at the same time as they become resistant. These new proteins coelectrophorese with three of the four new proteins produced in leaves of Xanthi plants following TMV infection. Such leaves are also resistant to further infection with TMV. Resistance to infection breaks down and the proteins disappear when injected or infected plants are kept at 32” for l-2 days (1). In experiments reported here injection with acetylsalicylic acid (aspirin) also induced the formation of b proteins and resistance to TMV in Xanthi tobacco plants. A 0.02% solution of aspirin, adjusted to pH 6.5 with 1 N NaOH, was injected into
half-leaves of 9- to lo-week-old plants of tobacco cv. Xanthi-nc. The other half of each leaf was similarly injected with water. Four days later the entire upper surface of each leaf was inoculated with TMV at 5 pug/ml. Injection with aspirin decreased the number of local lesions by over 90% (see Table 1). The few lesions that did occur on the treated half of the leaf were very small as are any lesions that develop on polyacrylic acid injected half-leaves (1). The resistance disappeared when treated plants were kept at 32” for 2 days. Protein extracts (2) made at pH 2.8 from leaves injected 7 days previously with aspirin solution, when electrophoresed on polyacrylamide gels were found to contain the same three b proteins as those induced by polyacrylic acid (Fig. 1). A 0.01% solution of salicylic acid and a 0.1% solution of benzoic acid (the pH of both
TABLE 1 RESISTANCE
OF LEAVES, BENZOIC
Tobacco cultivar
Water
Aspirin
Xanthi-nc Samsun NN White Burley
642” 288 407
57 0 31
PREVIOUSLY INJECTED WITH ASPIRIN, SALICYCLIC ACID, TO INFECTION BY TMV 4 DAYS LATER
Reduction (%) 92” 100
92
Water 228 639
435
n Total number of lesions from eight half-leaves. b Mean of three experiments. 0042-6822/79/160410-03$02.00/O Copyright 6 1979 by Academic Fress, Inc. All rights of reproduction in any form reserved.
410
ACID,
OR
Salicylic acid
Reduction (%)
Water
Benzoic acid
Reduction (%)
18 67 25
92 90 94
648 294 404
23 22 16
96 93 96
SHORT COMMUNICATIONS
411
ante or b proteins. Benzoic acid, salicylic acid, and aspirin are all negatively charged and induce resistance whereas methyl salicylate is neutral and does not induce resistance even when a 0.1% solution is injected. Polyacrylic acid does not induce resistance a -b, to TMV or the formation of b proteins in c-b, the Samsun NN (Antoniw and White, sub--bl mitted for publication) or White Burley (3) cultivars of tobacco although similar proteins are produced in response to TMV infection in these varieties (4) (Antoniw and White, submitted for publication). However aspirin, benzoic acid, and salicylic acid induce both resistance (Table 1) and the formation of new proteins (Fig. 1) in these varieties. These results widen the range of chemicals --ba b that could be investigated with a view to --b, controlling virus infection in the field. Pre-h liminary experiments suggest that although both aspirin and polyacrylic acid induce resistance when applied to the plant as a . i i'. spray or by watering the soil, aspirin is effective at lower concentrations than polyacrylic acid. In one experiment only 17 lesions appeared when a 0.05% solution of aspirin was sprayed onto 8 Xanthi-nc leaves which were inoculated 10 days later with 5 pug/mlTMV. The 8 control leaves sprayed C with water produced 228 lesions. The induction of resistance and produc-3 tion of b proteins following virus infection -2 w-1 has been likened to the interferon system in animals (5). Interferon, like the resistance and associated b proteins in tobacco, is FIG. 1. Electrophoresis on 10% acrylamide gels of induced in animal tissues by synthetic polysoluble leaf proteins extracted at pH 2.8 from (a) anions or virus infection (1, 6, 7), and its Xanthi-nc, (b) Samsun NN, and (c) White Burley. The induction is inhibited by actinomycin D (5,6X leaves analyzed were (i) healthy, (ii) inoculated with It has been shown (8) that aspirin, salicylic TMV, (iii) injected with aspirin, (iv) injected with acid, and benzoic acid inhibit multiplication salicylic acid, and (v) injected with benzoie acid. of encephalomyocarditis virus in primary b,-b, and 1-3 are new proteins. mouse embryo tissue cultures. In view of the similarity between the interferon and solutions adjusted to 6.5 with 1 N NaOH) b protein systems it would be interesting when injected into Xanthi-nc leaves also in- to discover more about the mechanism of duced resistance and the formation of new this inhibition. proteins (Table 1 and Fig. 1). It has been suggested (1) that induction of resistance in REFERENCES tobacco by polyacrylic acid may depend upon the molecules’ negative charge because polyI. GIANINAZZI, S., and KASSANIS, B., J. Gen. Viral. 23, 1-9 (1974). acrylamide (neutral) does not induce resistI
II
Ill
IV
v
412
SHORT COMMUNICATIONS
2. GIANINAZZI, S., PRATT, H. M., SHEWRY, P. R., and MIFLIN, B. J., J. Gen. Viral. 34, 345-351 (1977). 9. KASSANIS, B., and WHITE, R. F., Phytopathol. 2. 91, 269-272 (1978). 4. VAN LOON, L. C., Physiol. 289-300 (1975).
Plant
Pathol.
6,
5. KASSANIS, B., and WHITE, R. F., J. Gen. Viral. 25, 323-324 (1974). 6. LOEBENSTEIN, G., Annu. Rev. Phytopathol. 10, 177-206 (1972). 7. KASSANIS, B., GIANINAZZI, S., and WHITE, R. F., J. Gen. Viral. 23, 11-16 (1974). 8. KOCHMAN,. M., MASTALERZ, P., and INGLOT, A. D., Nature (London) 207, 888-890 (1965).
99, 410-412
(1979)
SHORT COMMUNICATIONS Acetylsalicylic
Acid (Aspirin) Induces Resistance Virus in Tobacco
to Tobacco
Mosaic
R. F. WHITE Rothamsted
Experimental Station, Harpenden,
Hertfordshire
AL,5 ZJQ, England
Accepted August 23, 1979
Tobacco cv. Xanthi-nc becomes resistant to tobacco mosaic virus (TMV) and produces b proteins when injected with the interferon inducer polyacrylic acid. Injection of acetylsalicylic acid (aspirin), benzoic acid, or salicylic acid also induces this response in Xanthi-nc. Injection of aspirin, benzoic acid, or salicylic acid similarly induces resistance and the formation of new proteins in the White Burley and Samsun NN cultivars of tobacco.
Tobacco, Nicotiana tabacum cv. Xanthinc, becomes completely resistant to infection with TMV 2-3 days after injecting the leaves with a 50 pg/ml solution of polyacrylic acid, molecular weight 3500 (1). Three new proteins (b,-b,) appear in the injected leaves at the same time as they become resistant. These new proteins coelectrophorese with three of the four new proteins produced in leaves of Xanthi plants following TMV infection. Such leaves are also resistant to further infection with TMV. Resistance to infection breaks down and the proteins disappear when injected or infected plants are kept at 32” for l-2 days (1). In experiments reported here injection with acetylsalicylic acid (aspirin) also induced the formation of b proteins and resistance to TMV in Xanthi tobacco plants. A 0.02% solution of aspirin, adjusted to pH 6.5 with 1 N NaOH, was injected into
half-leaves of 9- to lo-week-old plants of tobacco cv. Xanthi-nc. The other half of each leaf was similarly injected with water. Four days later the entire upper surface of each leaf was inoculated with TMV at 5 pug/ml. Injection with aspirin decreased the number of local lesions by over 90% (see Table 1). The few lesions that did occur on the treated half of the leaf were very small as are any lesions that develop on polyacrylic acid injected half-leaves (1). The resistance disappeared when treated plants were kept at 32” for 2 days. Protein extracts (2) made at pH 2.8 from leaves injected 7 days previously with aspirin solution, when electrophoresed on polyacrylamide gels were found to contain the same three b proteins as those induced by polyacrylic acid (Fig. 1). A 0.01% solution of salicylic acid and a 0.1% solution of benzoic acid (the pH of both
TABLE 1 RESISTANCE
OF LEAVES, BENZOIC
Tobacco cultivar
Water
Aspirin
Xanthi-nc Samsun NN White Burley
642” 288 407
57 0 31
PREVIOUSLY INJECTED WITH ASPIRIN, SALICYCLIC ACID, TO INFECTION BY TMV 4 DAYS LATER
Reduction (%) 92” 100
92
Water 228 639
435
n Total number of lesions from eight half-leaves. b Mean of three experiments. 0042-6822/79/160410-03$02.00/O Copyright 6 1979 by Academic Fress, Inc. All rights of reproduction in any form reserved.
410
ACID,
OR
Salicylic acid
Reduction (%)
Water
Benzoic acid
Reduction (%)
18 67 25
92 90 94
648 294 404
23 22 16
96 93 96
SHORT COMMUNICATIONS
411
ante or b proteins. Benzoic acid, salicylic acid, and aspirin are all negatively charged and induce resistance whereas methyl salicylate is neutral and does not induce resistance even when a 0.1% solution is injected. Polyacrylic acid does not induce resistance a -b, to TMV or the formation of b proteins in c-b, the Samsun NN (Antoniw and White, sub--bl mitted for publication) or White Burley (3) cultivars of tobacco although similar proteins are produced in response to TMV infection in these varieties (4) (Antoniw and White, submitted for publication). However aspirin, benzoic acid, and salicylic acid induce both resistance (Table 1) and the formation of new proteins (Fig. 1) in these varieties. These results widen the range of chemicals --ba b that could be investigated with a view to --b, controlling virus infection in the field. Pre-h liminary experiments suggest that although both aspirin and polyacrylic acid induce resistance when applied to the plant as a . i i'. spray or by watering the soil, aspirin is effective at lower concentrations than polyacrylic acid. In one experiment only 17 lesions appeared when a 0.05% solution of aspirin was sprayed onto 8 Xanthi-nc leaves which were inoculated 10 days later with 5 pug/mlTMV. The 8 control leaves sprayed C with water produced 228 lesions. The induction of resistance and produc-3 tion of b proteins following virus infection -2 w-1 has been likened to the interferon system in animals (5). Interferon, like the resistance and associated b proteins in tobacco, is FIG. 1. Electrophoresis on 10% acrylamide gels of induced in animal tissues by synthetic polysoluble leaf proteins extracted at pH 2.8 from (a) anions or virus infection (1, 6, 7), and its Xanthi-nc, (b) Samsun NN, and (c) White Burley. The induction is inhibited by actinomycin D (5,6X leaves analyzed were (i) healthy, (ii) inoculated with It has been shown (8) that aspirin, salicylic TMV, (iii) injected with aspirin, (iv) injected with acid, and benzoic acid inhibit multiplication salicylic acid, and (v) injected with benzoie acid. of encephalomyocarditis virus in primary b,-b, and 1-3 are new proteins. mouse embryo tissue cultures. In view of the similarity between the interferon and solutions adjusted to 6.5 with 1 N NaOH) b protein systems it would be interesting when injected into Xanthi-nc leaves also in- to discover more about the mechanism of duced resistance and the formation of new this inhibition. proteins (Table 1 and Fig. 1). It has been suggested (1) that induction of resistance in REFERENCES tobacco by polyacrylic acid may depend upon the molecules’ negative charge because polyI. GIANINAZZI, S., and KASSANIS, B., J. Gen. Viral. 23, 1-9 (1974). acrylamide (neutral) does not induce resistI
II
Ill
IV
v
412
SHORT COMMUNICATIONS
2. GIANINAZZI, S., PRATT, H. M., SHEWRY, P. R., and MIFLIN, B. J., J. Gen. Viral. 34, 345-351 (1977). 9. KASSANIS, B., and WHITE, R. F., Phytopathol. 2. 91, 269-272 (1978). 4. VAN LOON, L. C., Physiol. 289-300 (1975).
Plant
Pathol.
6,
5. KASSANIS, B., and WHITE, R. F., J. Gen. Viral. 25, 323-324 (1974). 6. LOEBENSTEIN, G., Annu. Rev. Phytopathol. 10, 177-206 (1972). 7. KASSANIS, B., GIANINAZZI, S., and WHITE, R. F., J. Gen. Viral. 23, 11-16 (1974). 8. KOCHMAN,. M., MASTALERZ, P., and INGLOT, A. D., Nature (London) 207, 888-890 (1965).