Sajith Babu, D., Sansamma George and Nishan, M.A.
College of Agriculture, Vellayani, Thiruvananthapuram, Kerala – 695522
Abstract: The field survey on floral diversity and dominance was carried out to develop a database on the floral diversity and relative species dominance in wetland rice ecosystem of Thiruvananthapuram district during the first and second crop seasons, in both cultivated and fallow fields. The results revealed that in the cultivated fields during both seasons, the most prominent weed species among the three classes of weeds (grasses, sedges and broad leaved weeds) wereIsachne miliacea, Cyperus iria and Monochoria vaginalis respectively. The relative dominance of the weeds in the fallows was found slightly different. While Isachne miliacea remained to be the dominant grass weed, the dominant sedge weed in the fallows was Cyperus distans during the first crop season while it was Fimbristylis miliacea during the second crop season. Monochoria vaginalis and Ludwigia perennis topped the list of broad leaved weeds in the rice fallows during first and second crop seasons respectively.
Keywords: Relative dominance,Weed flora, Wetland, Rice ecosystem, Rice fallow
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