Effect of planting date on growth, development, aerial biomass partitioning and flower productivity of marigold (Tagetes erecta L.) cv. Siracole in Indo-gangetic plains of West Bengal

Abstract: The investigation was carried out to evaluate the growth, flowering, yield and quality of African marigold cv. Siracole, as influenced by different planting dates. The crop planted on 9^th June (T₃) was found to have the highest plant height (96.93 cm). Maximum number of primary (5.3) and secondary (14.15) branches/plant, total fresh weight (502.00 g/plant), contribution by stem (385.00 g/plant) to the total fresh weight, higher dry (126.25 g/plant) matter accumulation and also the dry matter accumulation in stem per plant (98.00 g/plant) were found maximum with 12 April (T₁) planting. The individual leaf area (4.73 sq cm) on 90 days after planting was significantly higher in the crop planted on 16 May (T₂). It took minimum days (13.01 days) from visible bud to colour shown and bud emergence to full bloom (20.16 days), maximum diameter of individual flower (3.99cm) were found with 12 April (T₁) planting. Heaviest flower (2.55 g) was recorded with October 12 (T₇) planting. 16th May (T₂) planting produced maximum number (7434.67) of flowers per plot (6.4 m²). Maximum carotene content was noted with 12^th October (T₇) planting. Crops planted between 50^th MSW (T₉) 2011 to 3^rd MSW (T₁₀) 2012 produced very less crop biomass, dry matter content and flower yield.