Producing more food from less applied water is vital, particularly in arid and semi-arid regions which suffer from water scarcity. A study was conducted at the Research and Experimental Station, Faculty of Agriculture, Ain Shams University at Shalakan, Kalubia Governorate, Egypt, to evaluate the effect of two irrigation systems (trickle and modified furrow irrigation) and five maize (M)-cowpea (C) intercropping patterns (sole M-30, sole M-15, ridge side M: ridge side C, ridge M: ridge C and sole C) on weeds and maize ( Zea mays
L.) attributes, and water use efficiency (WUE). Trickle irrigation surpassed the modified furrow by 6.0 and 36.0% in kernels number row-1
and maize grain yield, respectively. The ridge M: ridge C intercrop was the most effective action for diminishing weed biomass. Intercropping patterns were substantially leveled with sole M-30 in maize grain yield. Ridge M: ridge C under two irrigation systems, along with Ridge side M: Ridge side C, and sole M-30 under trickle irrigation were the effective combinations for lowering weed biomass. Each intercropping pattern under trickle irrigation, surpassed its counterpart under modified furrow for promoting kernels number row-1
, 100 kernels weight and grain yield of maize. The applied water with trickle irrigation was lower than that of modified furrow irrigation, saving about 8.2% of irrigation water. Also, trickle irrigation achieved higher WUE (45.5%) over the modified furrow. Land equivalent ratio illustrated that ridge M: ridge C and ridge side M: ridge side C patterns saved 25 and 9% of land, respectively. Aggressivity showed that maize was the dominant crop, while cowpea was the dominated one.