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Effect of auxin type on some antioxidative enzymes during in vitro root induction of saffron (Crocus sativus L.) was investigated to reveal the variation of activities and isoenzyme banding patterns during root induction of saffron (C. sativus L.). Indole-3- butyric acid (IBA) and naphtalene acetic acid (NAA) at different concentrations were added to the solidified MS or B5 medium. Corm explants of saffron were placed on root inducing media and enzyme levels in explants prior or after adventitious root formation were measured and compared. Percentage of root formation on B5 medium containing 2.46 ìM IBA was highest; however the maximum number of root per explant and per cm2 observed on MS medium with 19.6 ìM IBA. Significant changes occurred in the activities of these enzymes. Some polymorphisms occurred in patterns of lactate dehydrogenase and esterase during root induction in different treatments.

Periwinkle (Catharanthus roseus) is one of the most important medical and ornamental plants in the world. In this investigation, periwinkle seeds, after sterilization were cultured on MS medium. Petiolesegments of seedlings (4 day old) were subcultured to medium containing various concentrations of NAA accompanied with Kin and subcultured to regenerate the callus and root. Callus and roots wereobtained from petioles in some of treatments. The extracts of callus and roots from different treatments were analyzed by spectrophotometer, TLC and HPLC with respect to the indole alkaloids producingcapacity. Alkaloids were produced callus and roots from petiole of C. roseus in the presence of 0.1, 5, 10 and 20 mg/l Kin and NAA. MS with 0.1 mg/l NAA + 0.1 mg/l Kin had the highest vindoline, catharanthine, vincristine and root organogenesis capacity. But the level of these alkaloids and ajmalicine were very low compared to that in petiole of intact plant, and the level of serpentine was similar. New roots, callus roots, and callus from MS medium containing 0.1 mg/l NAA + 0.1 mg/l Kin were subcultured in hormone-free and 0.1 mg/l NAA + 0.1 mg/l Kin media and for organogenesis and growth. The most alkaloids amount was produced in new roots and callus roots. The indole alkaloidlevels of new roots in new media were higher than in petioles of intact plants. In this study, 10-fold catharanthine, 125-fold serpentine, 0.5-fold vindoline and 0.34-fold ajmalicine were produced by newroots. The most interesting result was presentation of two important ant-cancer dimeric alkaloids, vinblastine and vincristine with amounts of 20-fold vinblastine and 6-fold vincristine to compare that inthe petioles of intact plants.

Light impact on growth of Skeletonema costatum at 20 treatments of light regimes including combination bf five intensities of 2000, 4000, 6000, 8000 and 10000 lux and four periods of (LightDark) 24:0, 18:6, 12:12 and 6:18 hours was studied. Daily random sampling was done for all treatments to determine cell concentration and growth rate. Among different light periods, growth rate was maximum and cell concentration was minimum at continuous light. At 4000 lux growth rate was higher than other intensities. However, there were not significant differences between treatments for growth, except 6:18 h (L:D); in this light period at different irradiances, growth rate and cell concentration was very low, and this made a significant difference between these treatments and others. The results showed that S. castatum's active cells adapted to light changes very well. But in older cells, i. e. the cells at late stationary phase or at death phase, there might be some growth disorders caused by environmental parameters, before active growth begin.