Influence of temperature and daylength on the phenological development of annual Medicago species with particular reference to M. truncatula, cv. Jemalong

Abstract

In a glasshouse and two growth-room trials, carried out in conjunction with 12 serial plantings in pots in the open, it was found that the phenological development of Medicago truncatula, M. tornata, M. aculeata, M. polymorpha, M. scutellata and M. littoralis cultivars differed markedly in response to vernalization. In M. truncatula cv. Jemalong daylength interacted strongly with vernalization. Using the data of the 12 serial plantings, a mathematical model was developed to predict the period from emergence to flowering using daylength and temperature inputs. Because of the differential influence of temperature and daylength on different genotypes it was concluded that a separate model would have to be developed for each cultivar.