Leaf ageing was initiated in wheat leaves by floating excised leaves on distilled water in darkness for up to three days. After a given period of time the leaves were blotted and wilted to a leaf water potential (ψleaf) of approximately — 12 · 102 k Pa and then placed in a sealed chamber so that the stress-induced ethylene could be determined. The longer the period of leaf ageing the smaller were the levels of stress-induced ethylene. Treatments which are known to delay leaf senescence, such as floating the leaves on solutions of 6-benzyladenine (BA) or in the light instead of in the dark, were found to partly restore or even enhance the stress-induced ethylene levels. For example leaves allowed to age for 1 day whilst floating on 10-4 mol l-1 BA solution produced up to 200% more ethylene than freshly harvested leaves when both were subjected to water stress treatment. When BA solutions were applied as foliar sprays to wheat seedlings, the day before wilting treatment, the amount of stress-induced ethylene diffusing from the freshly harvested leaves (i.e. no leaf ageing treatment) was significantly increased. This occurred when water stress was induced in the leaves by either immersing the roots of seedlings in carbowax solution or by wilting excised leaves in a stream of warm air. There was a substantial synergistic effect between BA treatment and water stress in relation to the amount of ethylene diffusing from the leaves. This effect was 7.5-fold in experiments where excised leaves were floated on 10-4 moll-1 BA solutions for 1 day prior to wilting and 4.7-fold for intact plants where the BA solution was applied as a foliar spray the day before water stress induction by carbowax. We can postulate from the experiments in this paper that leaf ageing (and/or the depletion of an ethylene substrate, probably a photosynthetic product or a substance derived from it) and the level of endogenous cytokinin are probably important factors which determine the amount of ethylene emanating from leaves during water stress. Moreover, the results suggest that wheat shoots may contain sub-optimal levels of cytokinins in regard to their potential ability to produce ethylene under stress.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
- ψleaf :
leaf water potential
Abeles, F.B.: Auxin stimulation of ethylene production. Plant Physiol. 41, 585–588 (1966)
Abeles, F.B., Holm, R.E., Gahagen, H.E.: Abscission: the role of aging. Plant Physiol. 42, 1351–1357 (1967)
Ben-Yehoshua, S., Aloni, B.: Effect of water stress on ethylene production by detached leaves of Valencia Orange (Citrus sinensis Osbeck). Plant Physiol. 53, 863–865 (1974)
Burg, S.P., Burg, E.A.: The interaction between auxin and ethylene and its role in plant growth. Proc. Nat. Acad. Sci. USA 55, 262–269 (1966)
Burg, S.P., Burg, E.A.: Ethylene formation in pea seedlings: its relation to the inhibition of bud growth caused by indole-3-acetic acid. Plant Physiol. 43, 1069–1074 (1968)
El-Beltagy, A.S., Hall, M.A.: Effect of water stress upon endogenous ethylene levels in Vicia faba. New Phytol. 73, 47–59 (1974)
Fuchs, Y., Lieberman, M.: Effects of kinetin, IAA and gibberellin on ethylene production, and their interactions in growth of seedlings. Plant Physiol. 43, 2029–2036 (1968)
Hall, M.A., Kapuya, J.A., Sivakuman, S., John, A.: The role of ethylene in the response of plants to stress. Pestic. Sci. 8, 217–223 (1977)
Imaseki, H., Kondo, K., Watanabe, A.: Mechanism of cytokinin action on auxin-induced ethylene production. Plant Cell Physiol. 16, 777–787 (1975)
Itai, C., Vaadia, Y.: Cytokinin activity in water-stressed shoots. Plant Physiol. 47, 87–90 (1971)
Jackson, M.B., Campbell, D.J.: Waterlogging and petiole epinasty in tomato: the role of ethylene and low oxygen. New Phytol. 76, 21–29 (1976)
Jordan, W.R., Morgan, P.W., Davenport, T.L.: Water stress enhances ethylene-mediated leaf abscission in cotton. Plant Physiol. 50, 756–758 (1972)
Kawase, M.: Effect of flooding on ethylene concentration in horticultural plants. J. Am. Soc. Hortic. Sci. 97, 584–588 (1972)
Kawase, M.: Role of ethylene in induction of flooding damage in sunflower. Physiol. Plant. 31, 29–38 (1974)
Lau, O.L., Yang, S.F.: Mechanism of a synergistic effect of kinetin on auxin-induced ethylene production. Suppression of auxin conjugation. Plant Physiol. 51, 1011–1014 (1973)
Lau, O.L., Yung, K.: Synergistic effect of kinetin on IAA-induced ethylene production. Plant Cell Physiol. 15, 29–35 (1974)
Lau, O.L., John, W.W., Yang, S.F.: Effect of different cytokinis on ethylene production by Mugn Bean hypocotyls in the presence of indole-3-acetic acid or calcium ions. Physiol. Plant. 39, 1–3 (1977)
Livne, A., Vaadia, Y.: Stimulation of transpiration rate in barley leaves by kinetin and gibberellic acid. Physiol. Plant. 18, 658–664 (1965)
McMichael, B.L., Jordan, W.R., Powell, R.D.: An effect of water stress on ethylene production by intact cotton petioles. Plant Physiol. 49, 658–660 (1972)
Morgan, P.W., Hall, W.C.: Effect of 2,4-dichlorphenoxyacetic acid on the production of ethylene by cotton and grain sorghum. Physiol. Plant. 15, 420–427 (1962)
Scholander, P.F., Hammel, H.T., Bradstreet, E.D., Hemmingsen, E.A.: Sap pressure in vascular plants. Science 148, 339–346 (1965)
Taylor, H.F., Knight, B.E.A.: The wheat seedling method for assessing growth-retardant properties. United States Dept. Agric. Handbook 336, 69–72 (1968)
Wright, S.T.C., Hiron, R.W.P.: (+)-Abscisic acid, the growth inhibitor induced in detached wheat leaves by a period of wilting. Nature 224, 719–720 (1969)
Wright, S.T.C.: The relationship between leaf water potential (ψleaf) and the levels of abscisic acid and ethylene in excised wheat leaves. Planta 134, 183–189 (1977)
About this article
Cite this article
Wright, S.T.C. The effect of 6-benzyladenine and leaf ageing treatment on the levels of stress-induced ethylene emanating from wilted wheat leaves. Planta 144, 179–188 (1979). https://doi.org/10.1007/BF00387268
- Leaf ageing
- Water stress