the effect of concentration, time and applying instruction of seaweed extract on some morphological characteristics of rooextract on some morphological characteristics of root and shoots of safflower (carthamustinctorius l.)t and shoots of safflower (carthamustinctorius l.)

in order to investigate the effect of concentration, time and consumption instruction of seaweed on some morphological characteristics of root and shoots of safflower, the present experiment in factorial form in a completely randomized design with three replications in research greenhouse of agriculture faculty, ferdowsi university of mashhad was conducted in 2014-15. factors examined included consumption concentrations of seaweed extract in four levels (non-consumption and consumption 1, 1.5 and 2 liters per hectare), consumption stages of seaweed extract in two levels (consumption at vegetative stage and consumption at reproductive stage) and applying instruction of seaweed extract at two levels (application as foliar application and as soil applied). the results showed that consumption concentrations of seaweed extract had a significant difference (p<0.01)on all the measured traits in the present experiment. consumption times of seaweed extract on all the measured traits except for the height of first branch from soil surface showed significant effect. consumption instruction of seaweed extract was significant on root volume, root dry weight, root density, biologic yield of main boll and height of first branch from soil surface. based on obtained results from interaction of concentration and time of seaweed extract consumption, the highest root dry weight and root density was related to two liters seaweed extract per hectare in the vegetative growth stage. consuming 1.5 liters per hectare seaweed extract, compared to non-consumption of the seaweed extract caused to 54.08 percent difference in total biological yield. also consuming seaweed extract in the reproductive stage compared to vegetative stage of plant allocated the largest biological yield thatthe difference was about 20.22 percent.