Effect Of Vichete 5g And Rifit 500 Ec On The Occurrence And Phytosociological Attributes Of Weeds In Rice Field

Abstract

Two herbicides namely Vichete 5G (12.5, 25.0, 50.0 kg/ha) and Rifit 500 EC (0.5, 1.0 L/ ha) were applied in BRRI Dhan 28 in the field to follow their effects on the occurrence and phytosociological attributes of weeds. A total of 29 weed species belonging to 22 genera covering 10 families was found to occur. 28 weed species under 21 genera and 9 families, 16 weed species under 14 genera and 6 families and 26 weed species under 21 genera and 10 families were assessed during 1st, 2nd and 3rd weedings respectively. 12 Species ( Eragrostis unioloides, Marsilea quadrifolia, Cyperus tenuispica, Murdania nudiflora, Fimbristylis miliacea, Rotala densiflora, Cyperus iria, Setaria pumilla, Fimbristylis diphylla, Leptochloe chinensis, Monochoria hastata and Oryza rufipogon) were recorded in first weeding but not found in second weeding. Cyperus rotundus, Panicum paludosum, Cyperus difformis, Marsilea quadrifolia and Echinocholoa crussgalli were found to be present at control only. They were controlled by the use of both herbicides. However, the number of weed species was found to reduce in the 2nd weeding in comparison to 1st one in all the treatments. Between the two weedicides, 50.0 kg/ha of Vichete 5G was relatively better than other doses of Vichete 5G and Rifit 500 EC and more effective to control weed species in 1st and 2nd weedings. In first weeding phytosociological attributes were highest in Schoenoplectus erectus and lowest in Rotala densiflora . In second weeding phytosociological attributes were highest in Eleocharis congesta and lowest in Panicum paludosum and Lindernia hyssopiodes while phytosociological attributes were highest in Fimbristylis miliacea and lowest in Marsilea quadrifolia of third weeding.

Asiat. Soc. Bangladesh, Sci. 42(2): 129-144, December 2016