Studies On Component Factors Of Yield And In Vitro Regeneration System Of Crocus Sativus L.

Saffron (Crocus sativus L.) belonged to Iridaceae family has been cultivated in Europe for many centuries for its stigmas, which is the world most expensive spice and is in great repute as medicinal agent with various therapeutic uses. Now the Saffron is also cultivated in China, Iran, India and other Asian countries. Most evidence from lab or clinic have showed that crocin, crocetin and safranal, which are contained in saffron stigmas, have various biological activities, such as cytotoxic, antitumor, anticarcinogenic, antimutagenic activities besides traditional medicine as emmenagogue and so on. Because of being triploid, saffron is consequentially sterile, and its beautiful flowers can't produce any seeds, propagation is possible only via corms. By conventional culture practice, the natural reproduction rate of new corms is quite low, and saffron production requires labor-intensive harvesting, including flower picking and stigma separation, thus the produce of saffron corm and stigmas can't satisfied the domestic marketIn this dissertation, a primary study of saffron on development biology of its corm was carried out, and the system of in vitro regeneration of saffron was established. At last some pathogenic fungi causing corm rottenness were identification and characterized.(1) Correlation analysis for the yield showed that there was positively linear correlation between fresh weight per corm (FW) and number of flowers per corm (FC) and number of shoots per corm (SC), correlation formula is FW = 2.063 *FC+11.228, R2 = 0.9555 and FW = 0.8891 *SC+10.14, R2 = 0.849, respectively. Averagely, FW below 10 g has 0.25 flowers and 2.25 shoots, FW between 10 g and 15 g has 1.34 flowers and 3.49 shoots, and FW above 15 g has 1.47 flowers and 5.00 shoots.Fresh weight of daughter-corms was affected by the FW, SC and cultured period of mother-corm. The higher the FW of mother corm was, the higher of the ratio between daughter corms and mother corm. The more SC, the more heavy total weight of strain was, the more light average weight of daughter corm, the more light weight of chief shoot corm; SC may increase slightly, if the mother corm was large enough. All of the axillary bud of small one should be erased. But this measure would bring injury of the mother corm and increased the risk of pathogen infection.(2) The 60Co γ -radial endurance of saffron corm would abate with its fresh weight decrease. Low dose of 60Co γ -radial would promote the axillary bud sprout.20 Gy was lethal for corm less than 1.0 g, 30 Gy was lethal for corm larger than 1.0 g.(3) Effects of age and variety of explants as well as of exogenous hormones on formation of...