EFFECT OF SPATIAL ARRANGEMENT AND DENSITY ON WEED INFESTATION AND YIELD OF MAIZE (ZEA MAYS L.)

Field experiments were conducted during summer season 2012 and consequently repeated in 2013 to assess the efficacy of row and plant spacing on weed infestation and yield of maize crop. The experiments were carried out in Randomized Complete Block (RCB) design with split plot arrangements. Three row spacings i.e. 60, 75 and 90 cm were assigned to main plots while different plant spacings i.e. 10, 15, 20, 25 and 30 cm were allotted to subplots, respectively. The results showed that for both the year's narrow row and plant spacing effectively suppressed weeds while wider row and plant spacing resulted in higher weed density. The data showed that the maximum weed density (202.07 and 218.70 m(-2)) was recorded in 90 cm row spacing in 2012 and 2013, respectively. However, among plant spacing highest weed density of 214.89 m(-2) and 219.83 m(-2) was recorded in 30 cm plant spacing during 2012 and 2013, respectively. The data regarding biological yield showed maximum biological yield in 60 cm row spacing while among plant spacing the highest biological yield was resulted in narrow plant spacing of 10 cm during both years. Furthermore, highest grain yield of 4928.9 kg ha(-1) in 2012 and 5063.9 kg ha(-1) in 2013 was recorded in 75 cm row spacing while lowest grain yield of 3026 kg ha(-1) in 2012 and 3989 kg ha(-1) in 2013 was observed for 90 cm row spacing. Among plant spacing highest grain yield of 4474.8 kg ha(-1) and 5228.5 kg ha(-1) was recorded in 15 cm plant spacing whereas lowest grain yield of 3554 kg ha(-1) and 4010.6 kg ha(-1) was observed for 30 cm row spacing in 2012 and 2013, respectively. The regression analysis also showed highest grain yield form 15-20 cm plant spacing during both years. Similarly the correlation data showed that with increase in weed density the grain yield decreases accordingly. The two years of research showed that narrow spacing (15-20 x 75 cm) enhanced the competitive ability of maize crop and suppressed weed growth.