an appraisal of photoperiod and temperature sensitive pre-flowering phase for two cumin (cuminum cyminum l.) landraces

in order to evaluate the different photoperiod and temperature sensitive pre-flowering phases in two cumin landraces a raciprocal transfer experiment from photoperiod 8 h to 16 h and vice versa under two different day/ night temperatures 20/10 and 30/20 ˚c was conducted. two model including ellis and adams were used to analyse the data and to quantify the duration of different developmental phases. the results indicated a high probability for variation in phototermal responses among the cumin landraces of iran. it was found that photoperiod sensitivity in azarshahr is greater than mashhad landrace. in addition it was found that temperature affects on the timing of different developmental phases. this is one of the main causes of errors in phonological models. different behavior of temperature sensitive and insensitive phases provides the possibility of testing the hypothesis about the role of different gene groups in general developmental procsess. it was clear that the temperature sensitivity for photoperiod genes of azarshahr landrace is higher than mashhad landrace. these results would contribute to better understanding of variation in photoperiod and temperature sensivity in cumin as well as optimization of phonological models.