اثرات اكوفيزيولوژيك آبياري و تاريخ كاشت بر روي رشد، عملكرد و اجزاي عملكرد گياه دارويي اينكسون

The Ecophysiological Effects of Irrigation and Sowing Date on Growth ,Yield and Yield Components of Anise (Pimpinella anisum L.)

Because of the importance of medicinal plants for producing natural based drugs, this study was conducted to evaluate the ecophysiological effects of irrigation and sowing date on Anise, which is used in drug and food industries. Five irrigation treatments : I,( irrigation was omitted during stern elongation), I2 (irrigation was omitted during stem elongation and grain filling stages), 13 (irrigation was omitted during umbel appearance), I4 (irrigation was omitted during grain filling period), and 15 (irrigation in all growing stages, as a control), were studied on three sowing dates (April 4, 16 and 29). The results showed that leaf area index (LAI), specific leaf area (SLA), plant height and biomass were decreased significantly in the third sowing date. Also these characteristics were decreased significantly by irrigation disruption in I1 and 12 levels. Stomatal frequency was reduced when sowing date was delayed. However, water stress in I3 and specially in I, and 12 levels increased stomatal frequency. The results also showed that the Stomatal length was decreased due to water stress in stem elongation and umbel appearance stages, but it was not affected by sowing dates. Grain yield ranged from 893.4 to 457.2 kg. ha^-1, for D1I5 and D3I2 treatments, respectively. The mean number of umbels in plant, umbelets in umbel, grains in umbelet and 1000 grain weight were significantly decreased when sowing date was delayed and plants were exposed to water stress. The results indicated that for successful grain production, Anise must have been sown early in spring (April 4) in Tabriz and water stress during grain filling period had no effect on yield of this plant.