Integrated weed management studies in cauliflower (Brassica oleracea var. botrytis L.)

Abstract

The present study was undertaken in cauliflower variety PSBK-1 to find out the effect of various weed control treatments on yield and contributing traits along with economics. A field experiment with 15 treatments was conducted at Hill Agricultural Research and Extension Centre, CSK Himachal Pradesh Krishi Vishvavidyalaya, Dhaulakuan during Rabi, 2004-05 and 2005-06. Simultaneously, another study comprising of 14 treatments was also conducted with the objective of determining the most critical period of crop-weed competition. The soil of the experiment fields was sandy loam in texture and slightly acidic in reaction (pH 6.0). The experiment was laid out in Randomized Block Design with three replications. Effect of various treatments was studied on total and species-wise weed count, total weed dry matter, weed control efficiency, crop growth and development, nutrient uptake by weeds and crop, yield attributes and yield of cauliflower. The dominant weeds associated with cauliflower were Coronopus didymus, Poa annua, Cyperus rotundus, Medicago denticulata and Ageratum conyzoides. The results revealed that oxadiazon 1.5 kg ha-1 and mulching with leaves reduced total and species wise weed count and total dry matter accumulation by weeds with the highest weed control efficiency and thus increasing the yield by improving yield attributes of cauliflower. Oxadiazon 1.5 kg ha-1 and mulching with leaves recorded maximum weed control efficiency of 54.91 and 53.31 per cent, respectively. Oxadiazon 1.5 kg ha-1 and mulching with leaves being statistically similar with each other resulted in significantly higher marketable yield and B:C ratio (136.8 and 130.8 q ha-1) and (1.27 and 1.18), respectively. The percent increase in marketable yield by oxadiazon 1.5 kg ha-1 and mulching with leaves over farmers practice was 27.51 and 21.96 per cent whereas, over unweeded check it was to the tune of 273.03 and 256.80 per cent, respectively. Another study resulted that the critical period of loss due to weeds was between 30 to 45 days after transplanting of the crop and removal of weeds during that period was most effective in increasing the yield of the crop.