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A field experiment conducted at Instructional farm, Rajasthan College of Agriculture, MPUAT, Udaipur during rabi 2016-17 and 2017-18 to study the effect of weed management practices on weed control and seed yield of fenugreek. The experiment consists of thirteen weed management treatments comprising imazethapyr (70 g ha -1 , 70 g ha -1 fb hoeing at 40 DAS), imazethapye 50 g ha -1 at 2-4 leaf stage of weeds, imazethapyr + imazamox 50 and 60 g ha -1 at 2-4 leaf stage of weeds, pendimethalin 750 g ha -1 PE, oxyfluorfen (120, 150 g ha -1 and 120 g ha -1 fb hoeing at harvest, oxadiargyl (100 g ha -1 and 100 g ha -1 fb hoeing at 40 DAS) including weed free and weedy check in main plot treatments and levels of vermicompost, viz. control and 5 t ha -1 in sub plot treatments. The experiment was laid out in split plot design with three replications. The soil of experimental field was clay loam in texture, slightly alkaline in reaction, medium in organic carbon, available nitrogen, available phosphorus and high in available potassium. Fenugreek variety RMT-305 was sown at 30 cm distance with 25 kg ha -1 seed rate and fertilize with recommended dose of fertilizers. Pre-emergence application of oxadiargyl 100 g ha -1 followed by hoeing at 40 DAS recorded significantly lower weed density (15.00 m -2 ) and weed dry matter (54.20 g m -2 ), higher weed control efficiency (86.29% ), crop resistance index (10.20), weed persistence index (1.79%) and lowest weed index (3.03% ). Also the same treatment recorded higher growth, yield attributes and seed yield (2820 kg ha -1 ) of fenugreek however this treatment was remained at par with weed free check.

Background: A field experiment was conducted at the Instructional Farm of Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur during Rabi 2016-17 and 2017-18 to study the weed flora, growth, yield and economics of fenugreek. The experiment was laid out in split plot design with three replications having Fenugreek variety RMT-305 (25 kg ha-1) and RDF of 40 kg N and 40 kg P2O5 ha-1 (basal dose through urea and DAP). Methods: Herbicide applied as pre-emergence (PE) at one day after sowing, while post-emergence (PoE) application at 2-4 leaf stage of weeds (21 DAS) with knapsack sprayer having flat fan nozzle using 500 liters of water ha-1. Result: The pooled results revealed that pre-emergence application of oxadiargyl 100 g/ha fb hoeing at 40 DAS recorded significantly higher weed control efficiency (82.3%), plant height (59.83 cm), number of branches (6.09), number of pods (44.86), number of seeds/pod (17.33), seed weight (9.05 g/plant) of fenugreek. Also, significantly maximum seed yield (2.82 t/ha), haulm yield (6.70 t/ha) and harvest index (29.7%) of fenugreek was recorded under oxadiargyl 100 g/ha PE fb hoeing at 40 DAS which was at par with weed free treatment. Significantly higher net returns (98158 `/ha) and B C ratio (2.63) was obtained with application of oxadiargyl 100 g/ha Pre-Emergence (PE) fb hoeing at 40 DAS. Residual effect of herbicides used in fenugreek did not showed any phytotoxic effect on succeeding summer fodder maize in terms of visual phytotoxicity rating at various growth stages of maize, weed flora, dry matter of weeds as well as crop at 30 DAS and green fodder yield of summer fodder maize.

A field experiment was conducted on clay loam soil during kharif, 2017 at Instructional Agronomy Farm, Rajasthan College of Agriculture, Udaipur to find out the best chemical weed management practices in maize. The experiment comprising 13 treatment combinations i.e. weedy check, atrazine 0.5 Kg ha-1 PoE at 10 DAS, atrazine 0.5 Kg ha-1 PoE at 15 DAS, atrazine 0.5 Kg ha-1 PoE at 20 DAS, atrazine  0.5 Kg ha-1  + halosulfuron  0.09 Kg ha-1 PoE at 10 DAS, atrazine  0.5 Kg ha-1  + halosulfuron  0.09 Kg ha-1 PoE at 15 DAS, atrazine  0.5 Kg ha-1  + halosulfuron  0.09 Kg ha-1 PoE at 20 DAS, atrazine  0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1 PoE at 10 DAS, atrazine  0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1 PoE at 15 DAS, atrazine  0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1 PoE at 20 DAS, atrazine  0.5 Kg ha-1  + topramezone 0.025 Kg ha-1 PoE at 10 DAS, atrazine  0.5 Kg ha-1  + topramezone 0.025 Kg ha-1 PoE at 15 DAS, and atrazine  0.5 Kg ha-1  + topramezone 0.025 Kg ha-1 PoE at 20 DAS.These 13 treatment  were replicated thrice in randomized block design with the objectives to find out the effect of herbicides and their tank mix  application on nutrition in plant as well as weed and chlorophyll content of maize and their economics. The minimum NPK  uptake by weeds at harvest also was found under the treatment of atrazine  0.5 Kg ha-1+  tembotrione  0.125 Kg ha-1 PoE at 15 days after sowing. All the weed control treatments increased the chlorophyll content of maize over weedy check. The post-emergence application of atrazine 0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1at 15 DAS  treatment resulted in maximum seed yield (5240 Kg ha-1) which was statistically at par with post-emergence application of atrazine 0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1 at 20 DAS (4963 Kg ha-1). The maximum uptake of total nitrogen (144.49 Kg ha-1) and phosphorus (34.99 Kg ha-1) by the crop was observed under application of atrazine 0.5 Kg ha-1  + tembotrione  0.125 Kg ha-1 PoE at 15 DAS, while  maximum uptake of potassium (130.42 Kg ha-1) recorded  in atrazine  0.5 Kg ha-1  + topramezone 0.025 Kg ha-1 PoE at 20 DAS which were significantly higher over all other herbicidal treatments.