Photoperiodism in Oats

Photoperiodic responses of plants have been the subject of many investigations. Garner and Allard (1920) working with soybeans and tobacco found that length of day played an important role in floral development. They further reported (1923) a close relationship between temperature and photoperiod in plant growth. Most of the common species of cultivated plants now have been investigated to determine their photoperiod requirements for flower bud initiation. Extensive literature reviews on this subject have been published by Murneek and Whyte (1948) and Leopold (1951). Although the literature pertaining to the photoperiodic response of certain crop plants such as soybeans, corn, and tobacco is extensive, only a few similar experiments dealing with small grains have been reported. Gfeller and Goulden (1954) showed that a light intensity of 1500 candle power or more is necessary for satisfactory growth of oat plants. Wiggans and Frey (1955) found that photoperiods of 18 to 24 hours caused a more rapid maturation of commonly grown oat varieties than did those of 12 to 15 hours. The study reported herein was conducted to determine the effect of different length periods of light on the date of heading, tillering, and plant height of oats