<abstract xmlns="http://www.w3.org/1999/xhtml">
				
				<p> Tobacco leaf disks were subjected to various types of lighting and chemical solutions to determine the interaction of these factors in leaf senescence. Far-red light promoted senescence more than light of lower wave-lengths. Magnesium at 50 mM was a potent inhibitor of senescence, whereas EDTA-disodium salt at 50 mM promoted senescence in the light but retarded senescence in the dark. Additional work with the effect of ethylene on detached leaves demonstrated that hydrolytic enzyme activity for amylase, peptidase and protease increased as a result of treatment but esterase activity decreased. The response differed with regard to variety and leaf maturity. Exposure to ethylene increased chlorogenic acid oxidase in lower leaves of pale yellow tobacco but decreased the enzyme in NC-95 lower leaves. These data relate to the growth behaviour of the two genotypes in that physiological maturity occurs at considerably different rates in pale yellow and NC-95 plants. The results help to explain why leaves of pale yellow plants tend to ripen within a much shorter time than leaves of conventional green tobacco cultivars. </p>
			</abstract>

Tobacco leaf disks were subjected to various types of lighting and chemical solutions to determine the interaction of these factors in leaf senescence. Far-red light promoted senescence more than light of lower wave-lengths. Magnesium at 50 mM was a potent inhibitor of senescence, whereas EDTA-disodium salt at 50 mM promoted senescence in the light but retarded senescence in the dark. Additional work with the effect of ethylene on detached leaves demonstrated that hydrolytic enzyme activity for amylase, peptidase and protease increased as a result of treatment but esterase activity decreased. The response differed with regard to variety and leaf maturity. Exposure to ethylene increased chlorogenic acid oxidase in lower leaves of pale yellow tobacco but decreased the enzyme in NC-95 lower leaves. These data relate to the growth behaviour of the two genotypes in that physiological maturity occurs at considerably different rates in pale yellow and NC-95 plants. The results help to explain why leaves of pale yellow plants tend to ripen within a much shorter time than leaves of conventional green tobacco cultivars.

Some Factors Influencing Tobacco Leaf Senescence

Tobacco Research Laboratory, Agricultural Research, Science and Education Administration, U.S. Department of Agriculture, Oxford, North Carolina, U.S.A.

Contributions to Tobacco & Nicotine Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

{"article-title":"Some Factors Influencing Tobacco Leaf Senescence"}

Tobacco leaf disks were subjected to various types of lighting and chemical solutions to determine the interaction of these factors in leaf senescence. Far-red...

Some Factors Influencing Tobacco Leaf Senescence

Pubblicato online: 14 ago 2014

Pagine: 48 - 56

Ricevuto: 02 ott 1978

Accettato: 26 apr 1979

DOI: https://doi.org/10.2478/cttr-2013-0468

© Beiträge zur Tabakforschung International

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.