Survey of Germination and Phenology of Dodder (Cuscuta campestris) in Sugar Beet (Beta vulgaris) Fields

Field dodder (C. campestris), as an obligate stem parasite, damages sugar beet fields of west Azarbaijan province severely. In this research, we evaluated germination indices and parasitic effects of field dodder on sugar beet yield under laboratory, greenhouse and field conditions in West Azarbaijan Agricultural and Natural Resources Research Center during 2014. Results showed that maximum germination percent (73 to 76 %) occurred at 25-30 ºC. By increasing the planting distance from 5 to 15 cm between sugar beet and dodder plants, dry weight of dodder reduced by 63% and root weight of sugar beet increased by 31.4 %. The dry shoot weight of sugar beets that were surrounded with dodder whitin 5, 10, and 15 cm distance as compared to sugar beet that were surrounded with no dodder (control) reduced by 38, 29, and 12.3%, respectively. Results also showed that field dodder life cycle, from seed to seed needed 716.9 growth degree-days. Finally, the flowering (473growth degree-days) and germination (95growth degree-days) periods were identified as the longest and lowest growing stage respectively.