Phytosociological study of weeds of wheat crop under edaphic variation: A case study from district Swabi, Khyber Pakhtunkhwa, Pakistan

The present study explains phytosociological attributes and communities structure of weeds of wheat crop under edaphic variation.This study was conducted in tehsil Razar district Swabi, Khyber Pakhtunkhwa, Pakistan during April 2016.A total of 200 quadrats having size (1x1 m 2 ) were established in 20 randomly selected wheat fields.Analytical quantitative characters i.e. density, frequency and cover were calculated for each weed species.Twenty weed communities were recognized on the basis of highest importance value (HIV) of three leading species.For each community, importance values (IV) of weed species were added to obtained total important value (TIV) of three dominant species and the remaining associated species.Sorensen's index was used to study similarity between weed communities.Higher similarity (76.1%) was recorded between Veronica-Papaver-Phalaris community and Trifolium-Cynodon-Melilotus community while lower similarity (16.6%) was recorded between Anagallis-Emex-Phalaris community and Veronica-Cerastium-Anagallis community.Physico-chemical analysis of soil showed that texture ranged from sandy-loam to loam, sandy clay-loam, slit-loam and loamy-sand or sand.Soil pH ranged from 5.8 to 8.1.Electrical conductivity (EC) ranged from 0.06 dsm -1 to 0.23 dsm -1 .Organic matter (OM) varied from 0.15% to 1.94%.While Calcium carbonates (CaCO3) ranged from 5.5% to 23.5%.It was concluded that soil texture, pH, electrical conductivity, Calcium carbonates and organic matter were strong edaphic variables that gives rise to diverse weed species composition, richness and distribution.This research will provide baseline knowledge about the weed ecology and it will be helpful in future studies.