STUDIES ON DODDER (CUSCUTA SPP.) INFESTATION IN CLOVER ( TRIFOLIUM ALEXANDRINUM L.) FIELDS IN SOME GOVERNORATES IN NILE DELTA

Set of field, laboratory and farmer questionnaire studies were conducted in three governorates in the Nile Delta i.e. Menoufia, Kafr El-Sheikh and Gharbia in the period from 2000/2001 to 2004/2005 winter seasons to throw light on the magnitude of dodder problem in Egyptian clover and provide information on dodder infestation level and measures for its control. Field surveillance study in 260 clover fields in Menouha governorate shows that 11.1% of surveyed fields were infested with dodder from Curvet? pfameora / pedicellata mixture appeared as scattered patches ranged from 0.25 to 22 m¹ in its size. Severity (%) Or covered area by dodder represents 0.52% of total surveyed area in clover fields over governorate. Results of seed contamination from 150 fanner seed samples were inspected in laboratory exerted that 87% of them were contaminated with dodder seeds with average 14.4 g / kg of clover seeds. Samples collected from certified seeds were free of dodder seeds. These result indicate that clover seeds represent the main source of dodder infestation. Germination study showed that optimum temperature for dodder seed germination was 15'C and it can germinate in range of 10-20 `C. Results of questionnaire study for 100 farmers, on thew awareness by dodder problem and available measures for controlling it, indicated that 85% of farmers suffer from dodder problem, 5% use certified or cleaned seeds and 20% of them have high infestation levels in scattered patches. The available practice for 50% of the farmers to control dodder is avouch mowing or hand pulling. It was shown that 68% of farmers need an effective package