Crop Weed Competition Study in Onion (Allium cepa L.) under Dry Temperate High Hills Condition of Himachal Pradesh
Abstract
Weed crop competition was studied to determine the critical period in onion (Allium cepa L.) during summer seasons of 1999 and 2000 at the Research Farm of H. P. K. V. Research Sub-Station, Lari (Lahaul and Spiti). Malva parvifora, Poa annua, Chenopodium album, Amaranthus sp., Anagalis arvensis and Melilotus indica were the dominant weed species associated with the crop. Among these M. pamiflora and P. annua were the most predominating weeds. Bulb yield loss increased with the increase in the duration of competition and maximum loss (594.7%) occurred due to full season competition. Significantly highest bulb yield and onion yield contributing characters were obtained in the plots remaining weed-free during the first 60 days after transplanting and resulted in 15.4 tons of onion bulb yield which indicated that the critical period of weed competition was found to be 60 days.
