Studies on weed dynamics in mustard (Brassica junceae L.) crop under Doon valley conditions of Uttarakhand

Weeds play an important role in the agriculture production system. They compete with main crop plant for water, nutrients, air and light resulting in poor crop growth and development. Weeds associated with mustard crop, categorized as broad leaved, narrow leaved, sedges and grassy weeds resulting in poor grain yield. Total eleven weed species were found in mustard crop field belonging to different family and genera. The experiment was conducted in Rabi season during the year 2018-2019. Maximum number of species belongs to broad leaved category of weeds classification. Three species were found to be grassy weeds followed with sedges. The weeds depending upon the type, density and duration of competition accounts for 23 – 70 per cent reduction in yield of mustard. Three species belongs to Poaceae family followed by Chenopodiaceae, Compositae, Asteraceae, Convolvulaceae, Fabaceae, Polygonaceae and Cyperaceae. Among the grassy weeds, Cynodon dactylon (L.) Pers. was the predominant weed followed by Polypogon monspeliensis and Phalaris minor. Cyperus rotundus L. was the only sedge present in the experimental field. Among the broadleaved weeds, Chenopodium album L. was the dominant one followed by Anagallis arvensis L., Parthenium hysterophorus L., Convolvulus arvensis, Melilotus albam Vicia hirsute and Rumex sp.