The interactive effects of vernalization, photoperiod and light intensity on the length of the apex or spike and main shoot, and the diameter of the main shoot of five different wheat (Triticum aestivum L.) cultivars (Çukurova-86, Atay-85, Lancer, Haymana79 and Bezostaya-1) having different biological characters were investigated. | Turk J Agric For 24 (2000) 475–486 © TÜBİTAK Interactive Effects of Vernalization, Photoperiod and Light Intensity on Reproductive Development of Wheat Cultivars Yasemin EKMEKÇİ, Serpil TERZİOĞLU Hacettepe University, Faculty of Science, Department of Biology, 06532 Beytepe, Ankara-TURKEY Received: Abstract: The interactive effects of vernalization, photoperiod and light intensity on the length of the apex or spike and main shoot, and the diameter of the main shoot of five different wheat (Triticum aestivum L.) cultivars (Çukurova-86, Atay-85, Lancer, Haymana79 and Bezostaya-1) having different biological characters were investigated. The research was carried out in four independent experiments, which were the combinations of two different photoperiods (12 and 16 ) and light intensities (200µmol m-2s1 and 500µmol m-2s-1 PFD) with different vernalization periods. At the end of each photoperiod and light intensity treatment, supplementary illuminance, which was arranged to be 35% of main light regime, was applied for two hours. Vernalization treatment was applied for 0, 15, 30, 45 and 60 days at 2 ±1˚C in a dark cold room at 80% humidity and also 90 days only in the short daylow light intensity experiments. In all experimens; ear emergence was completed in Çukurova-86 and Atay-85 in the control and all vernalization treatments while it was completed in Lancer, Haymana-79 and Bezostaya-1 in 30, 45 and 60 days of vernalization treatment. Since the spike development was slow in short day conditions and the required radiation was provided by high light intensity, the longest spike was obtained in the short day-high light intensity experiment. The shortest spike was obtained in the long day-high light intensity experiment. Low light intensity accelerated the transition of the apex from the vegetative to the reproductive stage through an effect probably similar to that of vernalization, only in short day conditions. The length of the main shoot increased
