Effect of plant spacing and weed-management practices on growth, biomass and steviol glycosides of candyleaf under western Himalayas

A field experiment was conducted during 2015 and 2016 to study the effect of plant spacing and weed-management practices on development, yield and steviol glycosides of candyleaf [Stevia rebaudiana (Bertoni) Bertoni] in the western Himalayas. Treatments included 2 plant spacings (45 cm × 45 cm and 60 cm × 45 cm) and 5 weedmanagement practices [weedy check, weed-free, hand-weeding, pendimethalin at 1.5 kg/ha followed by 1 handweeding (HW) at 40 days after spray (DAS) and oxyfluorfen at 0.25 kg/ha followed by 1 HW at 40 DAS]. Weed population and weed dry biomass under different plant spacing remained unaffected during both the years. Number of leaves (1792.58), dry leaf biomass (1481.32 kg/ha) and total dry biomass (3914.65 kg/ha) were significantly high under narrow spacing. However, total steviol glycosides (%) were significantly high (11.05%) under wider row spacing. Weed population (9.39/m²) and dry biomass of weeds (11.53 g/m²) were significantly reduced by the application of oxyfluorfen. Significantly higher number of leaves (2010.83), dry leaf biomass (1498.90 kg/ha) and total dry biomass (4256.45 kg/ha) were obtained with oxyfluorfen during both the years. Steviol glycoside content (12.05%) was significantly higher in hand-weeded plots. A spacing of 45 cm × 45 cm with application of oxyfluorfen could manage weeds efficiently for the perennial crop of candyleaf - a natural sweetner under western Himalayas.