Weed icide Trade name Formu lations Sele ctivity Weeds Controlled Mode of action Dosage Dala pon Dow pon W.P = 85% Selective trans located, pre and post emer gence herbi cide Sorghum halepense, Cynodon doctylon, Agropyron repens, Setaria sp., Panicum sp., Digitaria sp. Absorption and translocation is both by roots and shoots Uptake by leaves is significant Inhibits elongation of roots within 4 hours and root growth ceased within 12 hours thus weakens regenerative capacity of grasses. Persistence in soil is very fast only 2-4 weeks. --- TCA (Tri chloro acetic acid)   W.P = 90% Selective trans located, pre and post emer gence herbicide Sorghum halopense, Agropyron repens, Cynodon dactylon Highly soluble and rapidly absorbed and translocated by roots. 5 to 10 kg/ha. Alac hlor Lasso EC 48%, Gra nules 10% Selective mostly as pre- eme rgence annual grasses and certain broad leaved weeds. Absorbs mainly near the first node of germinated shoots, secondarily by roots and translocated throughout the plant and then metabolized with in 10 days. 2-3 kg/ha. Dinitra mine Cobex EC. 25% Selective pre emer gence Annual grasses and broad leaved weeds Prevents germination of seeds and inhibits root growth. Strongly absorbed by soil and not leached through the soil. 0.5 to 0.75 kg a/ha Nitra lin Plana vin W.P = 75% Sele ctive pre- emer gence Annual grasses and broad leaf weeds particularly crab grass, water grass and foxtail are highly sensitive. Absorbed only by seeds or roots by imbibing water. Inhibits cell division. Relatively immobile or stable in soil and leaches very slowly. 0.5 to 2.0 kg/ha. Triflu ralin Teflon EC 48% Gra nules 5%. Sele ctive pre- emer gence Echino- chloa crusgalli, Digitaria spp, Setaria spp, Sorghum halo-pense, Chenopo- diumalbum. Amaranthus spp., Tribulus terrestris, Portulaca sp., Affects seed germination and only actively growing young tissues such as root tips and coleoptiles. It is not applied to plant foliage since there is no contact activity. Strongly absorbed on soil colloids and shows no leaching. Persists in soil for 4 to 6 months and hence it has the potential for seasonal weed control. 0.5 to 1.5 kg/ ha. Amit role Weeda zol, ami zol WP 50% Non-selective, trans located pre or post- emer gence her bicide, mostly used in non-cropped areas. Amaranthus viridis, Euphorbia sp., Cirsium arvense Rhus radi- cams Calotropis procera; Agropyron repens, Cynodon dactylon, Cyprus rotundus, Poa annua, Allium sp., Setaria gluca Echornia crassipes, Typha sp. Readily absorbed by the foliage. highly mobile and hence readily translocated to rhizomes of perennial weeds, deep in to the soil and injure auxillary buds through foliar application. Produces phytotoxic symptoms, showing bleaching first in young and then older leaves. is readily absorbed on organic soils but has very short residual life(2-4 weeks) --- Diuron Kar mex W.P 80% Non Sele ctive pre- emer gence Digitaria sp., Echinochloa crusgalli, Sorghum halopense, Setaria sp., and broad leaf weeds like Amaranthus sp., portulaca sp., Ipomea sp., chenopodium album Absorbed mainly through the root system and translocated for leaves. Inhibits photosynthesis and interferes with nitrogen metabolism. Absorption is more in clay soil with organic matter content. 4-10 kg/ha for annual weeds 15 to 30 kg/ha for perennials Monu ron Tel var WP 50% Non selective herbicide for general weed control in non-cropped areas. It is also used as selective pre- emer gence herbicide in low doses Digitaria sp., Echinochloa crusgalli, Setaria sp., Sorghum halopense, and broad-leaved weeds like Amaranthus, portulaca, chenopodium, convolvulus sp. Readily absorbed through root system and is translocated upward in the xylem. Inhibits photosynthesis and interferes with nitrogen metabolism. 0.5 to 5 kg/ha Selective Selectivity is the phenomena where in a chemical kills the target plant species in a mixed plant population without harming or only slightly affecting the other plants. It is considered to be the greatest single factor that helped in the success of chemical read control. Non selective The chemical kills all parts what come in contact will the herbicide. They are also used as contact herbicides. Translocated The plants absorb herbicides sprayed on plants and the toxic affects the growing parts and kills the plants. Presowing Application of herbicide before the crop is sown or transplanted. Pre-emergence Herbicide application after the crop is sown but before it has emerged. Post-emergence Application of herbicide after the crop has emerged from the soil. Details of Herbicides used in Cotton Dalapon Trade Name Dowpon Formulations W.P = 85% Selectivity A selective, translocated, pre and post emergence herbicide. Weeds Controlled Effective control of perennial grasses such as sorghum halepense, cynodon doctylon, Agropyron repens control grasses like setaria sp., panicum sp., digitaria sp., annual and emergent water weed like typha sp., Mode of action Absorption and translocation is both by roots and shoots Uptake by leaves is significant Though the absorption continued for 48 hours but first six hours is most important. Translocated readily via both apoplastic and symplastic systems Main accumulation in growing tips and meristimatic tissue Inhibits elongation of roots within 4 hours and root growth ceased within 12 hours thus weakens regenerative capacity of grasses. Leaches rapidly in soils Persistance in soil is very fast only 2-4 weeks. High rate of application accute plant toxicity – Rapid precipitation of cell proteins – destruction of cell constituents – intensive scorching of leaves. TCA (Trichloro acetic acid) Formulations WP 90% Selectivity Aliphatic compound. Selective translocated herbicide but at higher doses, it is non-selective and soil sterilant. Mostly applied to the soil as pre and post emergence and hence its uptake by roots is most significant. Weeds Controlled To control perennial grasses such as Johnson grass, (sorghum halopense) quack grass (Agropyron repens), Burmuda grass (cynodon dactylon) etc., Also effective for aquatic weeds. Mode of action Highly soluble and rapidly absorbed and translocated by roots. There after, it is exclusively transported via apoplastic system and accumulates in growing tissues. It reduces both cuticle and lamina thickness in leaves, Inhibits the enzymes, thus allowing the accumulation of toxic levels of free ammonia. Readily leached from the soil because of its high water solubility. Dosage The normal dosage is 5 to 10 kg/ha. It is a strong acid. It is corrosive to iron, fine alluminium also, corrosive to skin and irritant to eyes and hence to be used cautiously. Alachlor Trade Name: Lasso Formulations: EC 48%, Granules 10% Selectivity: selective herbicide, mostly as pre-emergence spray on the soil and hence sufficient soil moisture is a pre-requisite for its effectivity. Weeds Controlled annual grasses and certain broad leaved weeds. Mode of action Absorbs mainly near the first node of germinated shoots, secondarily by roots and translocated throughout the plant and then metabolized with in 10 days. Inhibits protein synthesis on susceptible plants. It inhibits growth of young seedlings by inhibiting root elongation, mitotic activity, enlargement of cells Inhibits production of by enzymes, amylase and protease in susceptible species. absorbed soil colloids, and the soil persistence is upto 10 weeks, no residual toxicity is found in the next crop because it breaks down with in 10-12 weeks. Dosage 2-3 kg/ha. Dinitramine Trade Name: (Cobex) Formulations: EC.25% Selectivity selective pre emergence or pre planting herbicide which is sprayed in the field and incorporated after application. Weeds controlled annual grasses and broad leaved weeds in cotton. The grassy weeds controlled include, ( barn yard grass, carpet weed, crabgrass, johnson grass, jungle rice, pursolane.) Mode of action prevents germination of seeds and inhibits root growth. Strongly absorbed by soil and not leached through the soil. Dosage 0.5 to 0.75 kg a/ha Nitralin Trade name: (Planavin) Formulations: WP = 75% Selectivity selective pre-emergence or pre-planting herbicide. Which is incorporated in the soil through mechanical means. Weeds Controlled Annual grasses and may broad leaf weeds particularly crab grass, water grass and foxtail are highly sensitive. Mode of action not absorbed by plant foliage and there fore is not a post emergence herbicide. Absorbed only by seeds or roots by imbibing water. inhibits cell division. relatively immobile or stable in soil and leaches very slowly. Dosage 0.5 to 2.0 kg/ha. Trifluralin Trade Name: Teflon Formulation: EC 48% Granules 5%. Selectivity a selective pre-emergence or pre-plant herbicide, applied on the soil and incorporated with in 8 hours after application. Weeds Controlled grasses like Echinochloa crusgalli, digitaria species, setaria spp., sorghum halopense and certain broad leaved weeds such as chenopodium album. Amaranthus spp., Tribulus terrestris, portulaca sp., Mode of action affects seed germination and only actively growing young tissues such as root tips and coleoptiles. It is not applied to plant foliage since there is no contact activity. several biochemical responses including changes in carbohydrates, lipids, nitrogen and nucleic acid content. inhibits nodule formation and induce nitrogen deficiency symptoms. inhibits accumulation of cotyledonory reserves. strongly absorbed on soil colloids and shows no leaching. persists in soil for 4 to 6 months and hence it has the potential for seasonal weed control. Dosage 0.5 to 1.5 kg/hac. Amitrole Trade Name: weedazol, amizol. Formulation: WP 50% Selectivity heterocylic compound non-selective, translocated pre or post-emergence herbicide, mostly used in non-cropped areas. pre-plant treatment in cotton and orchards and also used as a defoliant in cotton. Weeds Controlled Perennial broad leaved weeds like Amaranthus viridis, Euphorbia sp., cirsium arvense (Canada thristle), Rhus radicams (poison ivy), Calotropis procera (milk weed); certain annual grasses/sedges Agropyron repens, cynodon dactylon, cyprus rotundus, poa annua, Allium sp., setaria gluca and also some aquatic weeds like Echornia crassipes, Typha sp., etc., Mode of Action readily absorbed by the foliage. highly mobile and hence readily translocated to rhizomes of perennial weeds, deep in to the soil and injure auxillary buds. Through foliar application. Readily translocated to the meristimatic tissues through symplastic and apoplastic systems. inhibits chlorophyll formation, affects formation of chloroplasts in younger leaves, causing photosynthetic disruption and there by inhibits regrowth. Produces phytotoxic symptoms, showing bleaching first in young and then older leaves. is readily absorbed on organic soils but has very short residual life(2-4 weeks) Diuron Trade Name: Karmex. Formulation: W.P 80% Selectivity relatively non-selective herbicide and mostly applied as soil sterilant. at low rates, it acts as pre-emergence herbicide and selectively controls germinating broad leaved and grassy weeds. used as pre-emergence in cotton At high rates it acts as non-selective general weed killer and also act as soil sterilant in non-cropped areas. Weeds controlled an effective weedicide for the control of annual and perennial grasses and herbacious weeds. the main weeds controlled are: Digitaria sp., Echinochloa crusgalli, Sorghum halopense, Setaria sp., and broad leaf weeds like Amaranthus sp., portulaca sp., Ipomea sp., chenopodium album etc., Mode of action absorbed mainly through the root system and translocated for leaves. inhibits photo synthesis and interferes with nitrogen metabolism. Used as pre-emergence treatment, provide adequate moisture in the soil to activate the herbicide. absorption is more in clay soil with organic matter content. Dosage 0.5 to 4 kg/ha in crop areas, 4-10 kg/ha for control of annual weeds 15 to 30 kg/ha for perennials in non cropped areas. Monuron Trade Name: Telvar Formulation: WP 50%. Selectivity an urea compound. non selective herbicide for general weed control in non-cropped areas. It is also used as selective pre-emergence herbicide in low doses (1-3 kg/ha) to control annual weeds. result is obtained when applied to just emerged weeds. Weeds controlled grassy weeds controlled are Digitaria sp., Echinochloa crusgalli, Setaria sp., Sorghum halopense, and broad leaved weeds like Amaranthus, portulaca, chenopodium, convolvulus sp., Mode of Action readily absorbed through root system and is translocated upward in the xylem. inhibits photosynthesis and interferes with nitrogen metabolism. At higher rates, phytotoxicity persists more than one season. Dosage at 0.5 to 5 kg/ha, but as a soil sterilant at 10 to 15 kg/ha against perennial weeds.

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