This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Proebsting, W. M. Articles by Marx, G. A. Search for Related Content PubMed PubMed Citation Articles by Proebsting, W. M. Articles by Marx, G. A. Agricola Articles by Proebsting, W. M. Articles by Marx, G. A.

Articles

Photoperiodic Control of Apical Senescence in a Genetic Line of Peas ¹

Section of Genetics, Development and Physiology, Division of Biological Sciences, Cornell University, Ithaca, New York 14853, Department of Seed and Vegetable Sciences, New York State Agricultural Station, Geneva, New York 14456

An early flowering genetic line of peas (Pisum sativum L.), designated G2, has dominant genes at two different loci, both of which function in short days to greatly extend the reproductive phase and thus to delay apical senescence. Long days (18 hours) promote senescence in this line, but the effect is reversible by reinstatement of short days (9 hours) until 3 to 4 days before the apex senesces. The response to photoperiod was quantitative. Increasing the photoperiod from 14 to 18 hours led to a progressive decrease in the number of nodes formed prior to death of the apex. Induction of senescence was determined by the total number of hours of light and darkness rather than by the length of the dark period. Senescence required flower and fruit development as well as long days.