A Phyto-sociological Association of Weeds in Summer Kharif crops of Kashmir Valley under different eco-situations

The study on the phyto-sociological association of weeds in summer crops viz. rice (Oryza sativa), maize (Zea mays), saffron (Crocus sativus) and pulses of Kashmir valley was conducted during 2013 at varying altitudes from 1500 to 2500 m above mean sea level (amsl). Areas where rice is cultivated two eco-situations exist, first with abundance of soil moisture is infested with weed species like Potamagetone distinctus, Polygonum hydropiper, Monochoria vaginalis,Ammania baccifera, Gratula japonica,Cyperius defformis, C.irria, Scirpus juncoides etc. In second eco-situation where farmers have to irrigate rice fiels as per availability of water the fields are infested with weeds like Echinochloa crusgalli, Gratula japonica,Cyperius defformis, C.irria, Cyperus rotundus etc.Up to 1700 m maximum importance value index (IVI) of Potamogeton distinctus (29.28%) among broad leaves, Echinochloa crusgalli (27.15%) among grasses and Cyperus difformis (18.88%) among sedges was noticed in rice, Amaranthus viridis (20.33%) among broad leaves, Digitaria sanguinalis (16.9%) among grasses and Cyperus rotundus (20.14%) among sedges in maize and in saffron Star of Bethlehem (Ornithogalummbellatum) (31.85%) among grasses, Amaranthus virids (18.23%) among broad leaves and Cyperus rotundus (26.18%) among sedges. From 1700 to 2000m amsl maximum IVI of Potamogeton distinctus (33.03%) among broad leaves, Echinochloa crusgalli (15.48%) among grasses and Cyperus difformis(15.89%) among sedges was noticed in rice and Amaranthus viridis (22.08%) among broad leaves, Digitaria sanguinalis(17.15%) among grasses, Cyperus rotundus(14.53%) among sedges and among othersChenopodium album was 18.3% in maize + pulses. Above 2000 m amsl Potamogeton distinctus(33.59%) and Marsilea qadrifolia (28.35%) among broad leaves, Echinochloa crusgalli (17.08%) among grasses was, Cyperus difformis(17.11%) and Cyperus iria(17.12%) among sedges and among others Polygonum hydropiper was 17.18% in rice, in maize + pluses maximum IVI of 18.32% was of Amaranthus viridisamong broad leaves, 14.37% of Digitaria Sanguinalis and 14.93% of Cynodon dactylon among grasses, 12.96% of Cyperus rotundus among sedges and 13.53% of Medicago sativa was observed in maize +pluses.