بررسی اثرات تنش شوری روی جوانه زنی و رشد گیاهچه های برنج (Oryza sativa L.) و علف هرز سوروف Echinochloa cruss-galli))

One of the most important steps during the growth period is germination stage, that may affected by invironmental stresses, particularly salinity stress and plant and weed competition, then in order to compare the resistance to salinity in Rice and Barnyardgrass on germination and growth stage, an experiment was conducted in completely randomized design in laboratory of agronomy department of university of Guilan. The factors was consist of salinity stress treatments in nine concentrations include (-0/2, -0/4, -0/6, -0/8, -1, -1/2, -1/4 and -1/6 Mpa) and the concentration 0 (distilled water) was as control. Results showed that in concentrations of salinity consist (-0/6, -0/8 and -1 Mpa) the seedling growth of rice was higher than barnyardgrass and in the concentrations up to -1, seedling growth of barnyardgrass became high, that maybe because of this weed,s acclimation in stress condition.In Barnyardgrass seed germination percent and rate was higher than Rice, which could be due to the faster initial deployment and better use of available resources in Barnyardgrass. In general in both salinity and drought stress, the germination and seedling growth of rice and barnyardgrass were decreased with increasing of the salinity and drought stress concentrations.