Adaptation of red clover to the long day environment

Authors

• Seppo Pulli Agricultural Research Centre Dept, of Plant Breeding SF-31600 Jokioinen

DOI: https://doi.org/10.23986/afsci.72293

Abstract

Five known varieties and five local strains of red clover from the latitudes 60 to 66°N were studied in greenhouse conditions. Photoperiods during the growing period were 12, 16 and 20h day, night temperatures 17°and 14°C and light intensity 21.2 klux. The plants were cut three times. Flowering, height development and shoot DM yield were assessed at each harvest. The number of shoots and leaves per plant and leaf area per plant were determined at the second harvest and root size at the third harvest. After the second harvest one replicate of each strain under the three light regimes was placed at +4°C under an 8-h light regime at 10 klux for 26 days. For assessment of plant response to hardening conditions, chemical analyses were performed on roots for TNC, long-chain fatty acids and proline. The study showed that the adaptation of red clover to certain daylength conditions influences plant behaviour with respect to its growth, development and hardening. The present study on daylength and growth together with developmental and chemical analysis are useful for breeding.