Effects of salinity and temperature on germination of Hyssop (Hyssopus officinalis)

In order to study the effects of salinity stress (made by sodium chloride and calcium chloride) and temperature interaction on germination characteristics of hyssopus officinalis، an experiment was conduct on factorial basis and in a completely randomized design with three replication at laboratory of Khorasan Razavi Agriclultural and Natural Resource Research Center in 2010. In this experiment، different osmotic potentials (0، -3، -6 and -9 bar) and also different temperatures (20، 25، 30 and 35 centigrade degree) were used. In this research، the percentage and rate of germination، the length of radicle and plumule، length ratio of radicle and plumule and seed vigor characteristics has been measured. The results showed a very significant effect of salt levels، osmotic potential and temperature on the above characteristics. The mean comparison for percentage and rate of germination characteristics showed that calcium chloride with 63% and 7. 11 respectively had a significant difference with sodium chloride with 50% and 1.. The highest percent and rate of germination were seen in -3 bar osmotic potential made by calcium chloride in 25 centigrade degree. The highest length of radicle and vigor was in -3 bar osmotic potential made by calcium chloride in 20 centigrade degree. The highest length of plumule was seen in both sodium chloride and calcium chloride in 0 bar (control) osmotic potential and 30 centigrade degree. Generally while the osmotic potential increases and temperature goes up to 30 centigrade degree all the characteristics in sodium chloride and calcium chloride had a remarkable reduction. Also increment of high temperatures had more harmful effects in NaCl than CaCl2. Study the Hyssop plant response to different levels of salinity and temperature on germination stage، it will assist farmers in establishment and desirable production.