The present investigation was conducted keeping above aspect in mind at Regional Research Station (Hill zone), Uttar Banga Krishi Viswavidayalay, Kalimpong (1250 m asl), West Bengal, India during the year of 2012 and 2013. Our focus on present study was mostly confined to Lava (2200 m asl), Rishav (2000 m asl), Rimbhik-Phalut (3000 m asl), Sukhiapokhri and Algarah of Darjeeling Himalaya. Changes in temperature, precipitation and increasing carbon dioxide all have potentially important consequences for crop/weed interactions, which is evident from a consideration of the basic biology of weeds and crops. The cereals like wheat, maize, rice, and vegetable crops occupy the major proportion of cultivated land in the hill. The other important crops include pulses (mash, rajmash, gram, peas, lentil, cowpea), potato and mustard crop. Weeds have been considered enemies of the farmers and reduce crop yield 16 to 74%. Depending upon their diversity and intensity they cause severe losses in the productivity of field, orchard, vegetable crops and grasslands. Amongst various grassy weeds, population of Echinochloa colonum, E. crusgalli, Setaria glauca, Cyperus spp. Digitaria sanguinalis and Eleusine indica increased drastically from mid to high hill zone of Darjeeling Himalaya. Among broad-leaved weeds Polygonum sp. and Ageratum conyzoides dominate in warm mountainous regions of Kalimpong and Khurseong region. Commelina benghalensis, Brachiaria ramosa and Gallinsoga parviflora have been found dominating in low and mid-hill areas with slight rising of temperature. Digitaria sanguinalis and Amaranthus viridis predominate specifically in low hills (Taria belt) and shifted to high hill zone of Lava and Rishav due to change in weather parameter for last ten years.
Climate change, Hill, Temperature, Weed, Production potential
