Identification of most important weed species in wheat crop under high altitude in northern Pakistan

A field survey was carried out to highlight the most important and problematic weeds of wheat crop at District Dir (Lower), Pakistan during, 2016. The weeds were randomly sampled from the fields of wheat crop using a quadrate of size 1 m x 1 m randomly thrown at 5 different sites. The data were recorded on weed density, relative weed density weed frequency, relative weed frequency, importance value index, fresh biomass and dry biomass of weeds. The survey data showed that total 14 plant weed species, belonging to 10 families were collected and identified from the study area. The data further showed that the surveyed fields were mostly infested with Phalaris minor, Cannabis sativa, Stellaria media, Poa annua, Coronopus didymus, Medicago minima, Fumaria indica, Euphorbia helioscopia, Medicago denticulata, Malcolmia africana, Vicia sativa, Ranunculus muricatus, Avena fatua and Chenopodium album. While the dominant weed species of the wheat field were Phalaris minor, Cannabis sativa and Stellaria media. The results further revealed that the highest density (30.4 m-2), relative weed density (16.8%) and important valve index (25.1%) were recorded for Phalaris minor, while the lowest valves for these parameters were noted from Chenopodium album (4.3 m-2), (2.4%) (8.4%) respectively. Cannabis sativa showed the maximum valves for weed frequency (88%) and relative weed frequency (8.7%), while the lowest were recorded for Chenopodium album (60%) and (5.9%) respectively. The maximum fresh and dry biomass of 142.6 g plant-1 and 59.1 g plant-1 respectively were noticed from Cannabis sativa. While, minimum fresh and dry biomass were obtained from Medicago denticulata (17.2 g plant-1) and (8.8 g plant-1) respectively. Among the different identified weeds Phalaris minor (G.sokay), Cannabis sativa and Stellaria media are the most problematic weed of wheat crop and should be managed through integrated weed management approach in wheat crop in the target area.