اثرات تاريخ كاشت و مقادير متفاوت بذر مصرفي بر صفات كمي و كيفي اسفرزه

The effect of planting dates and seed rates on yield and quality of Plantago ovata Forsk

Isabgol due to its mucilage in seeds is very important in pharmaceutical industry. A field experiment was conducted in Mashhad during 2001-2002 growing season to study the effect of sowing date and seed rate on growth, phenology, yield and yield components of isabgol (Plantago ovata Forsk). Treatments were arranged in a split-plot design with three replications. Main plot consisted of five sowing date (6Nov, 6Dec, 5Mar, 4April, 5May), and sub plot consisted of four seed rates (4, 8, 12, 20 kg/ha). Results showed that duration of phonological stages decreased as sowing date was delayed. The effect of sowing date on morphological characteristics such as plant height, spike length, leaf and tiller number per plant was significant, but increasing seed rates had no significant effect on these characteristics. However, spike length was significantly influenced by sowing date and seed rate. Yield components such as number of spike per plant, number of seed per spike, number of seed per plant and 1000 seed weight decreased as sowing date were delayed and seed rates were increased. LAE and total dry mater increased by increasing seed rate and decreased by delaying in date of sowing. LAE was maximum in reproduction stage. Both seed rate and sowing date had significant effect on isabgol seed and biological yields. Maximum seed and biological yields were obtained in the third sowing date and they were reduced as sowing date was delayed. Both 1000 seed weight and harvest index were not significantly influenced by these treatments. Quality characteristics, which studied, were swelling factor, husk percent and mucilage percent. Sowing date had no significant effect on quality characteristics. However, highest quantity and quality of mucilage gained at third sowing date.