Effects of Scarification and Stratification on Seed Germination and Dormancy of Turgenia Latifolia, Cuscuta Sp and Sophora Alopecuroides in Different Temperature Regimes

One of the major problems with effective weed control is the presence ofdormancy in weed seeds. in this study, the effects of stratification and scarification on seed germination and dormancy of turgenia latifolia, cuscuta sp and sophora alopecuroides seeds in different temperature regimes were investigated. none of turgenia latifolia hulled seedsgerminated in any of the temperature regimes, whereas dehulled seeds germinated at 15 and 20dc. also, scarification by acid sulfuric as a means of promoting germination significantly increased germination percentages of cuscuta sp and sophora alopecuroides seeds. stratifying intact dormant seeds for 2, 4, 6, and 8wk increased germination rates dramatically. best turgenia latifolia seed germination was achieved with 8 wk stratification at 15 and 20dc (60 and 64%,respectively). stratification did not stimulate the germination of cuscuta seeds, whereas 8-wk stratification of sophora alopecuroides seeds increased germination up to 40% regardless of the germination temperature. the results showed that both seed coat-imposed and internal dormancy were the main causes of turgenia latifolia seed dormancy, whereas only seed coat-imposed dormancy was the main cause of cuscuta sp and sophora alopecuroides seeds.