The effect of drought stress on the germination percentages in some tree species

Especially the use of drought - resistant plant species reduce maintenance and irrigation costs as well as plants increase the retention and success to continue its life in arid landscape. In this study used some plant species have been studied to determine their tolerance to drought stress in gardens and parks in Kastamonu. For this purpose conducted -2, -4, -6 and -8 Bar water stress under the germination trials. Landscaping applications commonly used some species such as Cupressus sempervirens L., Ailanthus altissima (Mill.) Swingle, Pyracantha coccinea Roem, Thuja orientalis, Pinus sylvestris L., Sophora japonica, Cedrus libani A. Rich., Acer pseudoplatanus L., Pinus brutia Ten. and Pinus nigra Arnold. ssp. pallasiana (Lamb.) Holmboe. Their seeds were evaluated different levels of water stress in the germination percentage. PEG 6000 solution was used in the formulation of water stress. The seeds were exposed to constant temperature of 25 ° C for a period of 35 days at germination cabinet. As a result this experiment calculated of germination in different water stress levels what percentage has fallen, so the least affected by increased water stress were studied to determine the species. Also results showed increased water stress, reduce the percentage of germination in all species. The highest level of water stress - 8 Bar, which was also obtained stress level proportional germination values Pinus nigra Arnold. ssp. pallasiana (Lamb.) Holmboe (64.8%) and Pinus brutia Ten. (46.5%).