the effect of bio-fertilizers on growth and quantitative yield of cassia angustifolia vahl. in karaj region, iran

background & aim: cassia angustifolia vahl is a valuable medicinal plant that it is important for constipation treatment. according to the importance of organic agriculture in increasing the yield of medicinal plants, the effect of bio-fertilizer on quantities yields of cassia angustifolia vahl or senna in karaj region (iran) was examined. experimental: this research was carried out in randomized complete block design (rcbd) with four replications and 13 treatments in 2009-2010. the seeds of senna were scratched with h2so4 (73%), then the bio-fertilizers and chemical fertilizer were added before sowing. the leaf surface and its chlorophyll content (spad) were measured with delta-t and chlorophyll-meter. results & discussion: the highest effect on quantities yield of plant was obtained from chemical fertilizers treatment. the bio-nitroxin and mixture of two bio-fertilizers (bio-sulfur and bio-phosphate fertilizer) increased quantities yield of this plant. the fertilizer treatments had a significant effect on plant height, stem diameter, chlorophyll content, leaf area, leaf dry weight and leaf fresh weight (ppindustrial and practical recommendations: additive nitroxin as bio-fertilizers in soil for increasing quantitative yield of cassia angustifolia vahl is recommended.