Effects of Daily Photoperiod/Nyctoperiod and Temperature on Autumn Development of Crown Buds and Dormanc y, Freeze Tolerance, and Storage of Food Reserves in Latitudinal Ecotypes of Biennial White Sweetclover

Abstract

The investigation consisted of both an outdoor experiment and one conducted indoors in controlledenvironment chambers. Objectives were to determine during late-summer/autumn the effects of (a) the changing daily light/dark (photoperiod/nyctoperiod) pattern, and (b) seasonally lowering temperatures on pre-winter behavior of sweetclover. Measurements were made of certain morphological characteristics and various facets of the winter-hardening process. Both experiments were conducted at the University of Alaska’s Palmer Research Center (61.6°N) in southcentral Alaska