The estimation of viability equation in seeds of perennial rye (Secale montanum) under different conditions of temperature and moisture content

nvestigate the Ellis and Roberts deterioration model in seeds of Secale montanum seeds and to introduction constants of viability equation، this experiment was conducted in Tehran university، Department of agronomy and plant breeding during 1384-85. Seeds were provided by Secale montanum seed production station in markazi province and after determining seed viability، seed vigor and initial moisture content، seeds were adjusted to 9، 11، 13 and 15% and sealed hermetically in aluminum packets. Storage temperatures were 25، 35، 45 and55c˚. The interval of sampling depended on the storage conditions. Seed viability constants to predict seed longevity in this species was estimated. The viability equation for this species is: V=ki-p/105. 98-2. 65log10m-0. 025t-0. 000057t2. Relationionship between sigma and moisture content and temperature was determined and after probit analysis، survival curves were depicted in each condition. Sigma logarithm to moisture content and temperature lines were parallel. The results show that survival curves is constrained to a common origin. Also the results show that with increasing in moisture content، in each temperature، especially in high temperature، seed longevity decrease، is higher with increase in moisture content.