مشخصات پژوهش

In order to evaluate the effects of sowing date and intra rows spacing on yield, yield components and some of phytochemical characteristics on Roselle, a field experiment was conducted as a split plot layout based randomized complete block design with three replications in 2013 and 2014 growing season. Five sowing dates and three intra rows spacing were considered as main plots (11th and 30th March, 14th April, 5th and 22th May) and subplots (100, 75 and 50 cm), respectively. The results indicated that delayed sowing date significantly reduced plant height, number of bolls, number of branches per plant, calyx dry weight, calyx yield, seed yield and biomass yield. Plant height, calyx yield, seed yield and biomass yield were increased by reducing intra rows spacing. In addition, reducing the intra rows spacing decreased number of branches, number of bolls, calyx dry weight, seed weight, plant dry weight. Anthocyanin and vitamin C significantly reduced by delaying in sowing date. Sowing dates had no significant effect on total phenol but antioxidants were changed sowing dates. Intra rows spacing did not make any significant effect on phytochemical traits of Roselle. Based on the results, it seems sowing hibiscus tea in the late of March to mid-May and intra rows spacing 50 cm, under hot and dry climate condition in Jiroft-Iran would be suitable for increase final yield.