Rapid Propagation System in Vitro of Medicinal Plant Cynanchum Atratum Bunge

As a traditional Chinese medicinal material, Cynanchum atratum Bunge has been widely used in traditional Chinese medicine for its treatment of abscesses, acute urinary infection and hectic fever.Thus, wild resources of it have been endangered by overharvesting. Plant tissue culture technology is an important measure to protect wild resources of medicinal plants, including C. atratum. Therefore, a fast and efficient propagation system of C. atratum through axillary bud proliferation pathwayhas been established. Through axillary bud proliferation, the medium [MS+sucrose 30 g/L+Agar 7 g/L+NAA 0.2 mg/l+IBA 1.5mg/l+KT 0.5 mg/l] can effectively proliferate adventitious buds, and the induction rate was 100 %, proliferation coefficient could reach 8.56. MS medium was used to induce adventitious bud rooting, with rooting rate of 98% and no callus. The highest survival rate was 90% when the ratio of grass mud pond and orchard red soil was 1:1. To our knowledge this is the first report of rapid propagation system in C. atratum, it achieve rapid reproduction of C. atratum.

Regeneration of Pruatjan (Pimpinella pruatjan Molk): Axillary Bud Proliferation and Encapsulation

<p class="p1">Purwoceng (<em>Pimpinella alpina </em>KDS atau <em>Pimpinella pruatjan </em>Molk.) merupakan tanaman obat asli Indonesia yang terancam punah. Akarnya dapat dimanfaatkan sebagai obat afrodisiak, diuretik, dan tonik. Teknik kultur <em>in vitro </em>merupakan teknologi alternatif yang dapat diterapkan untuk konservasi dan perbanyakan tanaman tersebut. Mikropropagasi telah dilakukan melalui jalur organogenesis dengan proliferasi tunas aksilar dan enkapsulasi. Penelitian dilakukan di Laboratorium Kultur Jaringan BB-Biogen, Bogor mulai tahun 2004 hingga 2005. Penelitian ini terbagi atas empat percobaan, yaitu (1) optimasi lingkungan tumbuh kultur, (2) optimasi formulasi media untuk proliferasi tunas aksilar dan enkapsulasi tunas aksilar, (3) induksi perakaran, dan (4) aklimatisasi. Kondisi lingkungan kultur yang optimum adalah di <em>growth chamber </em>dengan suhu 9<span class="s1">o</span>C dan intensitas cahaya 1000 lux. Formulasi media terbaik untuk proliferasi tunas aksilar adalah media DKW dengan penambahan BA 4 ppm dengan eksplan berupa tunas tanpa daun. Penggunaan arginin 100 ppm lebih baik daripada glutamin 100 ppm dan modifikasi vitamin (mioinositol 100 ppm dan thiamine-HCl 1 ppm). Pada media yang sama, pertumbuhan tunas aksilar terenkapsulasi juga paling baik dan tunas tersebut dapat menembus kapsul alginat setelah 4 minggu dalam periode <em>in vitro </em>(85%). Penggunaan NAA 1,0 ppm menginduksi perakaran paling cepat (40 hari) dengan persentase perakaran paling tinggi (100%). Vermikulit bertekstur kasar paling baik untuk aklimatisasi tunas aksilar terenkapsulasi sedangkan arang sekam paling baik untuk aklimatisasi planlet.</p>

Axillary Bud Proliferation Approach for Plant Biodiversity Conservation and Restoration

Due to mainly human population pressure and activities, global biodiversity is getting reduced and particularly plant biodiversity is becoming at high risk of extinction. Consequently, many efforts have been deployed to develop conservation methods. Because it does not involve cell dedifferentiation of differentiated cells but rather the development and growth of new shoots from preexisting meristems, the axillary bud proliferation approach is the method offering least risk of genetic instability. Indeed, meristems are more resistant to genetic changes than disorganized tissues. The present review explored through the scientific literature the axillary bud proliferation approach and the possible somaclonal variation that could arise from it. Almost genetic stability or low level of genetic variation is often reported. On the contrary, in a few cases studied to date, DNA methylation alterations often appeared in the progenies, showing epigenetic variations in the regenerated plants from axillary bud culture. Fortunately, epigenetic changes are often temporary and plants may revert to the normal phenotype. Thus, in the absence of genetic variations and the existence of reverting epigenetic changes over time, axillary bud culture can be adopted as an alternative nonconventional way of conserving and restoring of plant biodiversity.

Research note: Micropropagation of Eucalyptus polybractea selected for key essential oil traits

A protocol for the micropropagation of Eucalyptus polybractea R.T. Baker (blue mallee) using axillary bud proliferation from lignotuber-derived explants is described. Three different ages of plants were used as explant sources: glasshouse-grown seedlings, field-grown saplings, and coppice of field-grown mature lignotubers. Explants from each source initiated successfully and no significant difference was observed for shoot proliferation, rooting success or hardening success between explant sources. Leaf oil quantity and quality for hardened clones transplanted to a field plantation were assessed after 3 months of growth. Ramets of all clones contained high quality oil with over 80% 1,8-cineole. For seedling-derived clones, foliar oil concentrations of ramets were higher than those of the ortets from which they were derived. For sapling and mature lignotuber derived clones the opposite was the case. This suggests that ontogenetic and physiological constraints may be influencing yield in the young ramets. The age of the explant source did not appear to influence the success of micropropagation, and as a result older plants (for which key oil traits are known) can be selected as elite plants for multiplying selected genotypes via micropropagation.