Effect of different weed management techniques on weed growth, quality and husk yield of psyllium (Plantago ovata)

摘要

The integration of herbicides with one weeding at 40 days after sowing (DAS) induced desirable quality parameters like swelling factor and husk recovery percentage and husk yield and decreased quality deteriorative parameters such as huskless (redden)seeds, huskless seed percentage, huskless seed weight and equal husked seed weight over sole application of the herbicides. Weed free check recorded the lowest weed growth and resulted in the lowest quality deteriorative parameters and the highest desirable quality parameters and husk yield, followed by two weeding at 40 and 60 DAS, isoproturon at 0.5 kg ha~(-1) as pre-emergence + weeding at 40 DAS and 2,4-D Na salt at 0.4 kg ha~(-1)+ weeding at 60 DAS. Among herbicides, pre-emergence application of isoproturon at 40 DAS and 2,4-D Na salt at 0.4 kg ha~(-1) + weeding at 60 DAS. Among herbicides, pre-emergence application of isoproturon at 1.0 and 0.5 kg ha~(-1) proved conducive to desirable quality parameters and seed husk yield over its post-emergenceapplication at 1.0 and 0.5 kg ha~(-1) and other herbicides. Levels of pendimethalin (0.5-0.75 kg ha~(-1)), fluchloralin (0.5-0.75 ha~(-1)) and alachlar granules (0.5 -1.0 kg ha~(-1)) proved phytotoxic (47.31, 57.28, 25.83, 35.45 21.33 and 34.31 % respectively) to psyllium crop and caused significant deterioration in quality and husk yield compared with tolerant herbicides. These herbicides registered negligible residues (0.0001-0.0009 ppm) in psyllium plants. Residues of herbicides like isoproturon, 2,4-D Na salt, pendimethlin, fluchloralin and alachlor granules were below detectable level in psyllium seeds.