Fresenius Environmental Bulletin, cilt.24, sa.8A, ss.2561-2566, 2015 (SCI-Expanded)
Cotton (Gossypium hirsutum L) seed germination is greatly influenced by variations in temperature and light conditions. Majority of cultivars had significant differences among them for ability to tolerate temperature stress with variable seed germination behavior at three temperatures. This study reports effects of varying temperatures on seed germination of five cotton cultivars SG-125, ST-468, Ozbek-100, Ozaltin-404 and Ayhan-107. Disinfected seeds of each cultivar germinated in between sandwiched tissue papers contained in culture vessels at three temperatures (4°, 20° and 30° C) and 45 μMol photons m-2 s-1 light intensity in growth chamber. The results confirmed that increase in temperature significantly accelerated germination with variable radicle emergence range (74.1-95%) in all cotton cultivars at 30° C in 2 days time. The germinated seeds of all cultivars in general and cv. SG-125 in particular had maximum shoot-root length, fresh shoot and root weight, dry shoot and root weight including seed vigor index at 30° C. The seeds of these cultivars showed slow germination at 20° C and inhibited germination at 4° C. Therefore, 30° C temperature was identified as optimum for early cotton seed germination and obtaining most healthy cotton embryos for meaningful use in genetic transformation studies.