In vitro propagation of a medicinal plant: Tripterygium wilfordii Hook f.

In this study a reliable protocol was developed for the establishment of commercial in vitro cultures of Tripterygium wilfordii Hook f.. Juvenile shoots from one-year-old elite plants were used as the source of explants. New axillary shoots were obtained after 30 days of culture on a MS medium supplemented with BAP （2.0 mg.L^-1） and NAA （0.1 mg.L^-1）. The optimal multiplication medium was a modified MS medium supplemented with BAP （1.0 mg.L^-1） and NAA （0.1 mg.L^-1）. This yielded a multiplication rate of 2.4 for each subculture. Slightly more than 92% of shoots rooted when cultured on a modified MS medium containing IBA （0.2 mg.L^-1） and activated charcoal （0.5 mg.L^-1）. Activated charcoal promoted both a strong and a high rooting rate during the rooting phase. Plantlets were transferred to pots for a short acclimatization stage in a greenhouse where 95% of the plantlets survived. This highly reproducible procedure can be adopted for large-scale propagation of T. wilfordii.

In Vitro Propagation Potential via Somatic Embryogenesis of the Two Maturing Early Cultivars of European Chestnut (Castanea sativa Mill.)

Turkey ranks the third in the production of chestnuts in the world having an important place both in domestic and global markets. However, the chestnut production and the number of trees have been diminishing in recent years. Therefore, in vitro propagation of the chestnut, in addition to the classical propagation techniques, should be applied. Especially the propogation of the early maturing cultivars and production of the quality chestnuts will provide a better income to the producer. Here, somatic embryo production and regeneration from the immature cotyledons of the early maturing cultivars of the European chestnut (Castanea sativa Mill), Haciibis and Karamehmet, were studied using the somatic embryogenesis, one of the in vitro propagation techniques. To induce the somatic embryogenesis, 168 different combinations were applied to both cultivars. The somatic embryogenesis rate in Haciibis cultivar, in which the interactions were observed among the applications, was found to be 9.9% while it was 11.1% for the Karamehmet cultivar. Dessication, cold treatment, gibberellic acid (GA3) and benzyladenine (BA) + naphthaleneacetic acid (NAA) applications were performed on the regeneration of the somatic embryos, and 40% conversion to plant was obtained with desiccation together with BA + NAA supplementation to the medium.

Micropropagation of yellow mangosteen:a valuable endemic tree of India

We developed a method for in vitro regenera- tion of Garcinia xanthochymus （yellow mangosteen） from matured seed segments. Multiple shoots were induced on woody plant （WP） medium supplemented with cytokinins. An average of 11 shoots per explant were regenerated from mature seed segments on WP medium containing 20 μM 6-benzylaminopurine. Histological analysis revealed that hypodermal cells of seed segments were initially involved in active division, which later developed into meriste- moids, subsequently leading to the formation of shoot buds. Shoot elongation was achieved by repeated subculturing of seed explants in shoot regeneration medium. Rooting of shoots was achieved on WP medium supplemented with indole-3-butyric acid or s-naphthalene acetic acid. Plant- lets were transplanted to pots containing soil： compost （1：1） and survival rate was 90 %.

Effects of chemical sterilization of the culture media,porous membranes and luminosity on in vitro culture of Eucalyptus grandis×Eucalyptus urophylla

Hybrid combinations of Eucalyptus have increased due to expansion of plantations into unconventional areas and to the search for higher quality timber.However,most of these species have difficulties surviving in vitro cultivation.Active chlorine and sealing systems are often used to reduce contamination and increase gas exchange.The aim of the present study is to evaluate the establishment,multiplication,elongation and adventitious rooting of E.grandis × E.urophylla.Two clones(C1 and C2) and four active chlorine concentrations(0.000%,0.001%,0.003%,and 0.005%) were tested in the establishment and multiplication phases.Three sealing forms(W/M,1/M and 3/M) and the same four active chlorine concentrations were applied to the elongation phase.Two luminosities(dark and light)and three sealings(W/M,1/M and 3/M) were tested during adventitious rooting.Active chlorine concentration of0.005% led to the lowest fungal contamination rate and to the highest in vitro establishment.Active chlorine concentration of 0.003% resulted in the greatest length and highest number of shoots per explant in the multiplication phase.There were no phytotoxicity problems and the quality of plants grown in an environment with active chlorine was maintained in comparison with those grown in an autoclave.The increase in gas exchange in ventilation systems had a positive impact on the in vitro growth and development of plants.