Abstract:
An experiment was conducted at the Agricultural Research Station, Mannuthy during the crop season of 1993 and 1994 to evaluate the joint formulation of anilofos (aniloguard) and 2,4-DEE for the control of weeds in dry-sown rice. The treatments included joint formulation of anilofos and 2,4-DEE (0.3 and 0.45 kg a.i./ha), anilofos (0.3 and 0.45 kg a.i./ha), 2,4 DEE (0.4 and 0.6kg a.i./ha), butachlor (1.25 kg a.i./ha). Unweeded and hand weeded control were included weeded control were included for comparison. The experiment was laid out in split splot desigh, replicated thrice.
The main weed species found during the first year were Cynodon dactylon, Digitaris sanguinalis, Eleusine indica, Cyperus rotundus, Cyperus iria, Cleome viscosa and Ageratum conyzoides. In the second year Isachne miliaceae, Saccolepis interrupta, Echinochloa colona, Fimbrystylis miliaceae and Cyperus iria predominated.
The population of grasses were reduced by the application of butachlor @ 1.25 kg a.i./ha at 3 DAS and joint formulation of anilofos and 2,4-DEE @ 0.45 kg a.i./ha at 9 DAS. The same treatments were equally effective in loweing the number of sedges and broadleaved weeds. With respect to weed control efficiency hand weeding was superior to the herbicides during the first year. However during the second year joint formulation of anilofos and 2,4-DEE recorded the highest weed control efficiency followed by hand weeding.
No severe phytotoxic symptoms and loss were observed consequent to the application of the herbicides. Tank mix application of anilofos and 2,4-DEE recorded the highest number of tillers/m2. Joint formulation of anilofos and 2,4-DEE @ 0.45 kg a.i./ha recorded the highest dry matter production by the crop.
Yield attributing characters and yield were higher in plots with joint formulation of anilofos and 2,4-DEE @ 0.45 kg a.i./ha at 9 DAS. The same treatment was more economical over other hericides in terms of total returns and benefit cost ratio.
