Phytosociological studies on weeds of wheat (Triticum aestivum) in the middle Indo-Gangetic plains

Abstract

Wheat (Triticum aestivum L.) is the second most important food crop of India next to rice but wheat fields are generally infested with a large number of weeds. Due to their highly competitive ability and allelopathic interference, weeds cause irreversible damage to the crop. The weed inventory surveys and phytosociological studies in wheat fields were conducted in Patna district of Bihar during 2016–18 to identify the weed flora composition, density, frequency and Importance Value Index of 30 major weed species in wheat. In this study, Asteraceae was found as the largest family in respect of weed species, whereas Poaceae and Leguminosae jointly occupied the second position in terms of number of weed species. Phytosociological studies further revealed that Phalaris minor (6.21) and Cynodon dactylon (5.32) have larger relative frequency among other weed species while Chenopodium album and Avena fatua have larger relative abundance in the study area. Studies on relative density of weeds revealed that densities of Phalaris minor (7.06) and Chenopodium album (5.39) were higher over other weed species and similar trends were also observed in respect of Importance Value Index of weeds. The study will be helpful in planning of weed management strategies in wheat crop in the respective area through which the losses in wheat yield could be minimized.

Keywords

• Importance Value Index
• Phytosociology
• Relative abundance
• Relative frequency
• Weed flora