Effect of integrated weed management practices on emergence of Parthenium hysterophorus L. and associated weeds and their impact on kharif maize (Zea mays L.) productivity

In a field experiment conducted at Central Research Farm, Allahabad Agricultural Institute?Deemed University, Allahabad, during 2005 and 2006, pre-emergence application of Atrazine @ 2.0 kg a.i./ha as well as its combination with mechanical weeding at 45 days after sowing resulted in best inhibition of emergence of Parthenium hysterophorus L., Phyllanthus niruri L., Sorghum halepense L., Eclipta alba L., Cynodon dactylon (L.) Pers and Cyperus rotundus L. In maize, pre-emergence application of Atrazine @ 2.0 kg a.i./ha as well as its combination with mechanical weeding at 45 days after sowing resulted in least weed population, dry weight and weed control efficiency (WCE). Maximum grain yield and yield attributes as well as maximum net return and benefit: cost ratio were obtained in the same treatment.