Dr. Ashutosh MishraHANUMAGOUDA BHARAMAGOUDRA2024-06-202024-06-202022https://krishikosh.egranth.ac.in/handle/1/5810210677The present investigation “Efficacy of Herbicides on weed control in African marigold (Tagetes erecta L.) cv. Kalkatia Laddu” was conducted during 2021-22 in the instructional farm of the Department of Floriculture and Landscape Architecture, College of Horticulture and Forestry, Jhalawar. The experiment consisted of eleven treatments replicated thrice in Randomized Block Design. Among the herbicidal applications, pre-emergence application of Oxyfluorfen @ 1.5 kg a.i/ha recorded minimum number of grass weeds, Broad leaves weeds, Fresh and Dry biomass of weeds at 30 DAT (2.62, 1.36, 3.68 g/m2 and 1.23 g/m2) and at 60 DAT (5.06, 2.72, 6.84 g/m2 and 2.28 g/m2). However, at later stage of crop growth i.e., 90 DAT minimum number of grass weeds (7.32), Broad leaves weeds (3.69), Fresh and Dry biomass of weeds (9.65 g/m2 and 3.21 g/m2) was observed in Weed free (Manual weeding) treatment. The maximum values for these parameters were recorded in control treatment. Similarly, maximum weed control efficiency (83.41% at 30 DAT and 77.24% at 60 DAT) was observed in Oxyfluorfen @ 1.5 kg a.i/ha. However, it was maximum (75.80%) in Weed free treatment at 90 DAT of marigold crop. The minimum weed index (0.00%) recorded in weed free treatment. However, control treatment recorded maximum values for these parameters. Similarly, application of Oxyfluorfen @ 1.5 kg a.i/ha resulted in the maximum plant height (29.16 cm, 54.22 cm and 73.74 cm at 30, 60 and 90 DAT, respectively), plant spread (21.56 cm, 51.31 cm and 67.02 cm at 30, 60 and 90 DAT, respectively), number of primary branches (8.48, 17.26 and 20.64 at 30, 60 and 90 DAT, respectively), stem diameter (7.49 mm, 11.26 mm and 14.26 mm at 30, 60 and 90 DAT, respectively), Fresh and Dry biomass of plants (483.52 g and 101.02 g), days taken to bud visibility (54.51 days), days taken from bud to flower opening (6.15 days), days to 50 % flowering (69.38 days) and maximum B:C ratio (4.49). The maximum fresh and dry weight of flowers (45.59 g and 5.71 g), chlorophyll content (1.82 mg/g), xanthophyll content (2.97 mg/g), essential oil content (0.167 %), number of flowers per plant (84.49), Flower yield per plant, plot, square meter and hectare (325.02 g, 8.12 kg, 2.02 kg and 203.13 q) recorded in Weed free treatment. The maximum flower diameter 91 (4.84 cm) was recorded in Atrazine @ 1.5 kg a.i/ha treatment. The minimum values for these parameters were recorded in control treatment. On the basis of present investigation, it can be concluded that, cultivation of marigold with application Oxyfluorfen @ 1.5 kg a.i/ha was found effective in controlling weeds and enhancing growth, flowering and yield of marigold crop.EnglishThesis