Four field experiments were conducted during four successive seasons of 2001, 2002, 2003 ant 2004 at EL-Manzalla district, Dakahlia Governorate in the salt affected regions, which close to Manzalla Lake, Egypt. The experiments were conducted to known weeds species associated with rice crop as well as to produce a program for controlling all weeds in rice fields with herbicides without any effect on rice yield. These treatments were included four herbicides with three different rates as well as three mixture combinations, hand weeding at two times at 30 and 45 days after planting and weedy check. The obtained results could be summarized as follows:
Survey of common weed species associated with rice in salted affected regions which close to Manzala Lake, were Eleocaris geniculata which was the predominant weed with the highest frequency and density at proportion of 76.6 % weed flora, Cyperus difformis which recorded the second rank 10.8 %, the occurrence of Echinochloa curus – galli reached 6.5 % and Ammannia spp. rank for four number in important 6 % in both seasons.
All weed control treatments gave better control number of total weed/m2, fresh weight of all weeds/m2 and dry weight of total weeds g/m2 as compared with weedy check. The tank – mixed application of bispyribac – sodium plus pyrazosulfuron – ethyl at (16 + 10 g ai/fed) released 100 % control of all weeds at 60 days after planting.
The results indicated that all weed control treatments significantly increased panicles length (cm), panicles weight (g), 1000-grain weight (g) and grain yield (t/fed). The tank – mixed herbicide of bispyribac – sodium plus pyrazosulfuron – ethyl at (16 + 10 g ai/fed) produced the highest grain yield (t/fed), while the lower grain yield (t/fed0 produced from the weedy check treatment.