Alleviation of the Thermodormancy of Lettuce(Lactuca SativaL.) Seeds

Publisher Website
Google Scholar
Abstract
Imbibed lettuce seeds become thermodormant even at moderately high temperatures (above 27°C), and this tendency is intensified by the absence of light. Moreover, such seeds can then no longer germinate at certain lower temperatures which would have permitted the germination of non-dormant seeds, and either light or an appreciably lower temperature is required to break this induced dormancy. The timing and the duration of the high temperature period are critical. A long enough cool period preceding a warm one during imbibition will prevent thermodormancy ; and a temperature that could induce thermodormancy, given for a short period early during imbibition, may even accelerate germination. A practical way of preventing thermodormancy is to soak lettuce seeds for 15 min in a 70–100 mg 1-1 solution of kinetin in dichloromethane. This does not wet the seeds, yet permits sufficient kinetin to be taken up to enable them, even when sown more than a year later, to germinate in complete darkness at considerably higher temperatures than untreated seeds, and without causing the morphological abnormalities that could result from treatment with gibberellic acid.

This publication has 0 references indexed in Scilit: