Germination of two Rumex Species in Response to Light and Soil Moisture Conditions

Photocontrol is a preventive method in weed management which aims to reduce the germination of photoblastic weed seeds. One of the basic researches in photocontrol is, identifying these species and their germination behavior in various environmental conditions. In this study, germination behavior of two Rumex species were investigated under two different soil moistures during nine months of burying in soil, in response to three different light conditions. Results showed both species are positively photoblastic but their response to soil moisture environment were different. Under the natural circumstances Rumex crispus showed a peak of germination in autumn and one in late spring, while R.obtosifolius seeds germinated greatly in late autumn, winter and spring, both in presence of light. R.crispus seeds became more sensitive to light when buried in dry soil and germination increased in full light condition. Dormancy of R.obtosifolius seeds seemed to alleviate more slowly in dry soil. Our results indicate that seasonal dormancy cycle would occur in both species under natural moisture conditions, and also there is a possibility of environmental factors replacing each other to satisfy germination requirements.