TITLE:
Weed Interference in Zero-Till Cotton (Gossypium hirsutum L.)
AUTHORS:
Ayyadurai Pachamuthu, Poonguzhalan Ramadoos, Sathya Priya Ramalingam
KEYWORDS:
Weed Density, Dry Weight, Weed Index, Critical Period, Yield
JOURNAL NAME:
Open Access Library Journal,
Vol.1 No.6,
September
25,
2014
ABSTRACT: An investigation to study the effect of weed competition on zero-till
cotton was carried out at the experimental farm of the Pandit Jawaharlal Nehru
College of Agricultural and Research Institute, Karikal during the summer
season (February to July) of 2007. The predominant weed species found in the
experimented field were Echinochola colanum L., Leptochloa chinensis L., Cyperus rotundus L., Trianthema portulacastru, Rotala densiflora, Eclipta alba, Phyllanthus maderaspatensis, Echinochloa colonum and Leptochloa chinensis. Weed population
increased between 20 - 60 days after sowing and decreased thereafter. Weed competition
during the first 20 days after sowing resulted in an average yield loss of 12.5
percent which increased to 96.5 percent with full season competition. The seed
cotton yield increased from 353 kg/ha to 2308 kg/ha as the initial weed- free
period was increased from 20 days after sowing (DAS) to full season. The
critical period of weed competition in zero-till cotton prevailed 20 to 60 DAS
during which the crop should be kept free of weeds to prevent the potential
losses in seed cotton yield.