Studies on weed diversity and its associated phytosociology under direct dry seeded rice systems

Chhattisgarh is commonly known as Bowl of rice where rice is grown as monocrop in the entire state whether soil is bhata, matasi, kanhar or black soil. Present study is based on the study of biodiversity of weeds under Direct Dry Seeded Rice Systems in Koria District (C.G.) Study was conducted to assess the phytosociological studies of weed species in paddy field at Baikunthpur, Koriya district, Chattisgarh. A total of 43 genera and 9 families of Dicotyledonae and 3 families of monocots and 1 Pteridophytes was also observed and 43 weed species were identified Ratio of Sedges: (Grasses:Broad-leaved weeds was calculated as 9:12:18 Ratio) under direct dry seeded rice systems. The results obtained indicated that Echinochloa colona, Cyperus iria and Cynodon dactylon were the most frequent in 2007; E. colona and C. iria were the most frequent in 2008 and 2009. The importance value index (IVI) revealed that the most important weeds within the community were Poaceae and Cyperaceae. Out of 12 angiosperm families the predominance was shown by monocot families Cyperaceae and Poaceae having and weed species, respectively. The pteridophyta family Marsileaceae was represented by 1 weed species