A field experiment was conducted with fourteen treatments (oxadiarzyl 0.180 kg/ha, pendimethalin 1.50 kg/ha, trifluralin 1.50 kg/ha and isoproturon 1.25 kg/ha alone and at half rate with hand weeding (HW), oxadiarzyl, pendimethalin and  trifluralin each at half rate followed by (fb) isoproturon 0.75 kg/ha (post), pendimethalin fb clodinafop each at half rate, hand weeding  twice and weedy check) at Palampur during Rabi 2006-2007 and 2007-08. Phalaris minor (28.2%), Avena ludoviciana (25.2%) and Lolium temulentum (19.2%) were the predominant grassy weeds. The broad-leaved weeds (Vicia sativa, Coronopus didymus and Anagallis arvensis) as a whole constituted 26.7% of the total weed flora. Hand weeding twice and pendimethalin fb isoproturon were more effective in reducing the population of P. minor. Pendimethalin + hand weeding and hand weeding twice were effective against A. ludoviciana. Similarly integration of one hand weeding with isoproturon and trifluralin and hand weeding twice effectively taken care of L. temulentum. Pendimethalin + isoproturon and hand weeding twice reduced N and S removal by weeds. Pendimethalin fb isoproturon and trifluralin fb isoproturon resulted in significantly higher yield attributes (silique/plant, seeds/silique, 1000-seed weight), seed yield and seed N per cent of mustard. Trifluralin + HW and pendimethalin fb isoproturon gave higher gross and net returns due to weed control over other treatments. Isoproturon resulted in highest net return per rupee invested on weed control (18.5).

A field experiment was conducted during 2008-09 and 2009-10 at G.B. Pant University of Agriculture & Technology, Pantnagar (Uttarakhand). The soil of the experimental field was clay loam texture, medium in organic carbon (0.66%), available phosphorus (27.5 kg P/ha) and potassium (243.5 kg K/ha) with pH 7.2. Experiment consisted of six treatments were laid out in randomized block design with four replications. In the experimental field Cyperus rotundus, Ehinochloa colona, Brachiaria reptans,Commelina benghalensis, Ipomoea spp. and Parthenium hysterophorus were major weeds in both the years. Beside these, Digitaria sanguinalis was also observed as major weed during 2009-10. Other weeds were Cleome viscosa, Corchorus acutangulus, Dactyloctenium aegyptium and phylanthus niruri. Lowest density as well as dry weight of total weeds were recorded under the treatment of three hoeing at 30, 60 and 90 days after harvesting (DAH) of main crop which was at par with per-emergence application of metribuzin 0.88 kg/ha followed by (fb) hoeing at 45 DAH fb 2,4-D 1.0 kg/ha at 90 DAH. The highest cane yield was recorded with the execution of three hoeings at 30, 60 and 90 DAH treatment which was closely fb metribuzin at 0.88 kg/ha at 3 DAH fb hoeing at 45 DAH fb 2,4-D 1.0 kg/ha at 90 DAH of main crop.

A field study was conducted during 2008 and 2009 at G.B. Pant University of Agriculture and Technology, Pantnagar to evaluate the effect of two seeding time (before and after onset of monsoon) and six methods of weed control in direct dry seeded rice. Among the weed control treatments, butachlor applied 1.5 kg/ha in year 2008 and broadcasting of Sesbania knocked down by the application of  2, 4-D (brown manuring) at 30 days after sowing in 2009 recorded lowest weed dry weight. Pre-emergence application of butachlor 1.5 kg/ha yielded highest followed by the application of pretilachlor 0.5 kg/ha and broadcasting of Sesbania knock down with 2,4-D 0.5 kg/ha at 30 DAS which were at par with each other during both the year of experimentation.

In the new alluvial soil of Navsari (Gujarat), a field experiment was conducted in Rabi season to study the yield, quality and post harvest life of onion (Allium cepa L.) cv. ‘Gujarat Onion White-1’ as affected by weed management and fertilizer levels during two conjunctive years of 2008-09 and 2009-10. Weed population were decreased significantly with application of pendimethalin 1 kg/ha or oxyfluorfen 0.24 kg/ha supplement with one hand weeding at 40 DAT during both the season of investigation. Echinochloa spp., Trianthema portulacastrum, Digera arvensis. Physalis minima. and Cynodon dactylon. were found as major weeds in experiment field. Further, pendimethalin 1.0 kg/ha followed by one hand weeding  produced higher onion bulb yield of 39.3, 36.6 and 38.0 t/ha during both years as well as in pooled, respectively and found at par with oxyflourfen 0.24 kg/ha + one hand weeding at 40 DAT and weed free treatments. In pooled, increasing fertilizer rate from 75% to 125% of RDF was found effective and the higher level of fertilizer (125% RDF) gave the highest bulb yield, which was 10.52 and 19.43% more than of the F2 and F1 levels, respectively. Regarding post harvest life of bulbs, weight losses (%), black mould development (%) and sprouting (%) were remained unaffected by weed management and fertilizer levels except significantly higher weight losses (%) was observed under weed management treatment. On the basis of interaction, it is inferred that the treatment combination of (pendimethalin 1 kg/ha fb one hand weeding at 40 days after transplanting supplement with 100% RDF) found most appropriate (39.86 t/ha) and profitable not only to secure the net return of   2,69,422/ha with  7.85 BCR per unit cost of onion production but also save 25% of fertilizer.

Movement studies were carried out using packed soil columns to know the distribution pattern of pendimethalin in clay loam and sandy loam under saturated and unsaturated conditions. Pendimethalin was applied at 20 mg/kg of soil and the soil columns were kept for movement studies at time intervals of 1, 3, 5, 7, 15, 22 and 37 days. The soils used in the study were clay loam and sandy loam. Pendimethalin remained primarily in the top soil layers. Under saturated conditions movement of pendimethalin was more in sandy loam as compared to clay loam. Under unsaturated conditions, pendimethalin showed more mobility in clay loam.  The increase in herbicide movement was observed with increase in days. The factors that influence movement are the herbicide solubility, soil structure and texture and the amount of water passing through the soil profile influenced movement of herbicide. Pendimethalin moved up to 20-25 and 5-20 cm under unsaturated and saturated conditions at 37 days after application, respectively.  In clay loam soil, under saturated and unsaturated conditions, pendimethalin moved up to 15-20 cm  at 37 days after application.

A field experiment was conducted during  2003-04 and 2004-05 to develop an effective weed management practice to study the effect of weed management practice in French bean cropping system under subtropical agro-ecosystems of western Uttar Pradesh. Pre-planting and pre-emergence application of fluchloralin 1.0 kg/ha and pendimethalin 1.0 kg/ha reduced the population of Anagallis arvensis, Melilotus alba, Melilotus indica and Phalaris minor significantly than weedy check and other herbicide treatments and resulted significant increase in growth and yield attributes, viz. plant height, no. of branches, dry matter accumulation, no. of pods/plant and seeds/pod, seed and straw yield of french bean. Maximum yield was recorded in fluchloralin 1.00 kg/ha and pendimethalin 1.00 kg/ha treatments with a corresponding value of 1.11 and 1.11 t/ha of French bean and 37.1 and 36.2 t/ha of fodder sorghum  during both the years of experimentation. Application of fluchloralin 1.0 kg/ha and pendimethalin 1.0 kg/ha increased the net return of French bean significantly over weedy check, besides at B: C. ratio of 1.18 and 1.12 during two cropping seasons.

Experiment was carried out under heavy black clay soil (vertisol) at the Experimental Farm,  N.M. College of Agriculture, Navsari Agricultural University, Navsari during two successive seasons of 2007-08  and 2008-09 to study the effect of varying plant population and weed management practices on weed flora and productivity of sweet corn (Zea mays L. Saccharata). Weed density and biomass was significantly lower with crop population of 1,11,111 plants/ha. Significantly higher green cob (9.5 t/ha) and green fodder (14.9 t/ha) yield with net return ( 75,779/ha) and benefit: cost ratio (5.36) was produced with plant population of 1,11,111 plants/ha and was at par with crop population of 83,333 plant/ha.  Significantly lowest weed biomass was recorded in weed free check which recorded highest yield of green cob (10.7 t/ha) and fodder (17.1 t/ha). Application of atrazine 1 kg/ha + hand weeding at 40 days after sowing was remunerative  with higher net return ( 88,873/ha) and benefit: cost ratio (6.72).

Field experiment was conducted during 2009-10 and 2010-11 at Agronomical Research Farm of Birsa Agricultural University, Ranchi with four tillage management (zero till rice and zero till wheat; zero till rice and conventional till wheat;  conventional till rice and zero till wheat and conventional till rice and conventional till wheat) in main plot and three methods of weed control practices viz.,weedy check, recommended herbicides butachlor 1.5 kg/ha pre-emergence + 2,4-D 0.5 kg/ha post-emergence for rice and isoproturon 0.75 kg/ha + 2,4-D  0.5 kg/ha post-emergence for wheat and two hand weeding (20 and 40 DAS for rice and 25 and 50 DAS for wheat) in sub plot to assess the productivity and profitability of rice -wheat (cropping system under conservation tillage. Direct seeded rice–wheat sequence with conventional tillage produced maximum rice equivalent yield 7.44 t/ha (for 3.1 t/ha rice and 3.6 t/ha wheat) and net return (Rs. 58,206/ha). Among weed control, rice-wheat either with butachlor 1.5 kg/ha pre-emergence + 2,4-D 0.5 kg/ha post-emergence in rice and isoproturon 0.75 kg/ha + 2,4-D 0.5 kg/ha post-emergence in wheat or, with two hand weeding in both crops produced maximum rice equivalent yield (7.4 t/ha and 7.8 t/ha) and net return (Rs. 62,258/ha and  Rs. 60,498/ha)

A field experiment was conducted at Agricultural Research Farm of  Banaras Hindu University, Varanasi to study the effect of methods of rice establishment and weed management practices in irrigated direct seeded rice. Treatment comprised of three crop establishment methods, viz. dry seeding after land preparation using stale seed bed method by shallow ploughing or by glyphosate 1 kg/ha, puddled wet seeded in main plot and five weed control measures in subplot, viz. weedy, hand weeding at 15 and 30 DAS, pendimethalin 1 kg/ha pre emergence followed by 2,4-D EE 500 g/ha at 30 DAS, butachlor 1 kg/ha pre-emergence followed by 2,4-D 500 g/ha, fenoxaprop-p-ethyl with safener 56 g/ha 15 DAS followed by ethoxy sulfuron 18 g/ha at 20 DAS in a split plot design replicated thrice. Crop establishment methods did not influence rice growth and yield components, and yield. Irrespective of method of establishment, hand weeding twice was found to be superior in managing weeds in DSR than all sequentially applied herbicide treatments.

A field experiment was carried out during Rabi season from 2007-2010 at Chatha, Jammu to find out relative efficiency of weed management practices in gladiolus (Tagets erecta L.). Result revealed significant enhancement in spike yield with 2 hand weedings at 20 and 40 days after transplanting (6.05 t/ha) and pendimethalin 2 kg/ha + 1 hand weeding (5.79 t/ha), both of which were superior to weedy check (3.25 t/ha). The highest weed control efficiency (78.2%) was also achieved with 2 hand weedings, followed by pendimethalin + hand weding 76.9%). Application of pendimethalin along with hand weeding proved to be economical.

A field experiment was conducted during Kharif seasons of 2010 at JNKVV, Jabalpur to study the efficacy of bispyribac-sodium and other herbicides against weeds in drilled rice.  The field was infested with grassy weeds viz., Echinochloa colona, Dinebra retroflexa, Cyperus iria, Eclipta alba and Phyllanthus niruri. The efficacy of bispyribac-sodium as post- emergence was significantly superior when applied at 80 g/ha over other herbicides. However, the application of bispyribac-sodium 20 g/ha was more remunerative. Among the herbicidal treatments bispyribac-Na 80 g/ha recorded maximum grain yield (4.59 t/ha) which was at par with other doses of bispyribac-Na except 10 g/ha and significantly higher as compared to cyhalofop-butyl and butachlor.

The experiment was laid out in split plot design and replicated thrice at Agricultural College and Research Institute, Madurai during Rabi 2009-2010. The main plot treatment consisted of mulching with crop residue and no mulch as control. Foliar spray of micronutrient mixture, NAA at 40 ppm, salicylic acid at 100 ppm, brassinolide at 0.1 ppm, triacontanol at 500 ppm and no spray were assigned to sub plot. Among the main plot treatments, mulching with crop residue effectively controlled the weed density of grasses, sedges and broad leaved weeds which increased the yield attributes. The eonomic parameters, viz. gross return, net return, and benefit cost ratio were higher in mulching. The subplot treatment foliar spray of NAA at 40 ppm reduced the weed density significantly, which also enhanced the yield and yield attributes despite recording more economic returns. When  both the main and subplot treatments combined together, they gave better control of sedges  at 40 and 60 DAS and grasses at 60 DAS due to shade effect of robust stature of plants. This treatment combination resulted in substantial increase in yield and yield attributes and also more economic returns.

Experiment carried out to assess the viability of Asian spider flower seeds revealed that presoaking embryos of Cleome viscosa in 1% H₂O₂  for 30 M followed by 0.2% tetrazolium (Tz) staining for 4 h showed pronounced improvement in staining compared to embryos not subjected to H₂O₂ that remained unstained.

Transplanted crop recorded the lowest total weed population and dry matter and similar to dry seeding on 0 days after nursery sowing. Total weed population and dry matter was lower under early sowing on 0, 7 and 14 DANS as compared to delayed sowings. Sequential application of herbicides effectively controlled Echinochloa sp. and D. sanguinalis while control of Eragrostis sp. and L. chinensis was very poor. Transplanted crop recorded the highest rice grain yield, at par with dry seeding on 0 DANS but significantly higher than dry seeding on later dates. Three hand hoeings gave significantly higher grain yield than herbicides. Rice seeding directly on 0, 7 and 14 DANS produced similar grain yield under herbicides and three hand hoeings. Further delay in seeding significantly reduced grain yield under herbicides as compared to hand hoeings.

field experiment was conducted to study the effect of different herbicides alone or in combination, viz. BCSAA 10717-2% + glyphosate (42% SC), BCSAA10717-500 (SC), It is glyphosate (42% SC), glyphosate (41% SC) and paraquat(24 SL) for management of annual and perennial broad-leaved weeds in grapes after October pruning of the year 2010-2011. Herbicide treatments in grape vineyard significantly reduced the total number of weed. Among the tested herbicides, the most effective weed control was recorded with BCSAA 10717 (2%) + glyphosate 42% SC (85.0 + 1700 g/ha) which showed lowest weed density of 22 (4.80) plants/m2 and lowest dry weight (0.212 g) of weed after 30 days. While paraquat (24 SL) found effective in increasing the yield with decreasing competition between grape vine and weed,  The highest yield (32.12 t/ha) was found in area where paraquat 24 SL was used for weed control. No phytotoxic signs or symptoms, viz. leaf tip/surface injury, wilting, vein clearing, necrosis, epinasty and /or hyponasty were observed by weed management treatments.

A field experiment was conducted during Kharif season of 2007 to study the weed management in pearlmillet inter-cropping systems. The experiment was laid out in factorial randomized block design and replicated three times. Pre-emergence application of pendimethalin at 0.75kg/ha and oxyfluorfen at 0.2 kg/ha decreased the crop growth and yield attributes, viz. plant stand, plant height, dry matter production, root weight and root length compared to two hand weeding due to some phytotoxic effect but superior to one hand weeding and weedy check. Significantly higher seed, stover, biological and pearlmillet equivalent yield were recorded in two hand weeding treatment over all other treatments except weed free. The N and P uptake of pearlmillet and net returns increased significantly under all the weed control treatments as compared to weedy check.

A field experiment was conducted during Rabi season of 2011-12 at Madurai to study the effect of brown manuring on weed dynamics, yield and yield attributes and economics of irrigated maize. The weed management practice of PE alachlor 1.0 kg/ha + brown manuring proved to be effective in registering the lowest weed density of grasses, sedges, broad-leaved weeds and total weeds at 20, 40 and 60 days after sowing (DAS) and was at par with PE alachclor 1.0 kg/ha + daincha as intercrop with in-situ incorporation on 35 DAS except at 20 and 40 DAS. The above said prominent treatment has also registered higher weed control efficiency (84.41, 92.15 and 89.65% at 20, 40 and 60 DAS, respectively). As a result, the above promising treatment   has  increased  the  yield attributes such as cob length (17.09 cm), no. of rows/cob (14.76), no. of grains/row (38.56) and 100-grain weight (23.57 g), which in turn reflected   in    registering  higher grain yield of  7,227 kg/ha and stover yield of 11,563 kg/ha. The net returns ( 45,993/ha) and benefit cost ratio (3.61) were also more in PE alachlor 1.0 kg/ha + Brown manuring. The weed management practice of PE alachlor 1.0 kg/ha + daincha as intercrop with in-situ incorporation on 35 DAS was found to be the next best treatment in recording the higher grain and stover yield and economic returns.