Standardization of zygotic embryo culture from Nerium oleander L. and comparative analysis of biosynthesized cardiac glycosides within in vitro and acclimatized plants

The primary result of our experiment revealed that the germination percentage of N. oleander mature seeds is only 30%. From this observation, the concept of protocol standardization for zygotic embryo culture of this plant was originated. Zygotic embryo culture was proved an efficient in vitro multiplication system of N. oleander. The maximum germination percentage (96%) of zygotic embryos was observed on ¼ MS medium with 15 gm/L sucrose, whereas the best growth medium was optimized as ½ B5 with same sucrose concentration. The second part of this study was aimed to find out the cardiac glycoside accumulation pattern in both in vitro and acclimatized plants. For this purpose, one-month-old in vitro plantlets and acclimatized plants were subjected to LC-MS analysis and 09 cardiac glycosides were detected and quantified in both the systems. Most of the cardiac glycosides including odoroside A (32.71 mg/gm DW), odoroside H (4.69 mg/gm DW) and oleandrin (0.52 mg/gm DW) were found to be accumulated at maximum level within in vitro plantlets. CG 840b (1.89 mg/gm DW) is the only cardiac glycoside, which was maximally accumulated in acclimatized plants. From this study, it can be concluded that, zygotic embryo culture is a better choice for in vitro multiplication of N. oleander when compared to matured seeds and in vitro grown plantlets of this species favor cardiac glycosides biosynthesis in comparison to acclimatized plants. Therefore, all future research on the enrichment of cardiac glycosides from this plant may be conducted on zygotic embryos derived in vitro grown plantlets or cultures.

Reproductive Characteristics of the Selected Cocoa (Theobroma cacao L.) Clones after Regenerated from the Somatic Embryogenesis Culture

This study was conducted to evaluate the reproductive characteristics of 4 elite cocoa clones (MCBC1, PBC230, KKM22 and KKM4) propagated via somatic embryogenesis culture. From the findings, all clones have similar reproductive characteristics with clones from conventional grafted. However, only KKM4 clone from immature zygotic embryo culture produced the shortest staminode to style distance of 1.83 mm. This consequently influenced flower stability by reducing the efficiency of pollination by insects. It was found that this clone also has the highest number of flowers drop after anthesis (5 flowers) and lowest production of cherelle (5 cherelles). Further observation revealed that floral development from first bud visible (BBCH51) to flower anthesis (BBCH68) of all clones took around 31 days. These cocoa flowers which remained receptive soon after anthesis at 10 am (day-31) until the next day (day-32) suggesting 2 days’ period of receptivity. HIGHLIGHTS It is crucial to assess the presence of off-type characteristics in the reproductive organ structure such as the distance between staminode to style, period of reproductive cycle and stigmatic receptivity of cocoa clones regenerated from somatic embryogenesis The converging and parallel type of staminode to style distances are the ideal flower spatial arrangements for the optimal pollination in cocoa plant compared to splay type Only KKM4 clone propagated from immature zygotic embryo culture showed variation in the distance between staminode to style distance and this caused pollination failure by insect which then consequently caused minimum cherelle production All regenerated cocoa clones observed with typical period of the reproductive cycle and stigmatic receptivity GRAPHICAL ABSTRACT

Kultur In Vitro Endosperma, Protokol yang Efisien untuk Mendapatkan Tanaman Triploid secara Langsung

<p>In Vitro Culture of Endosperm: An efficient protocol to<br />propagate triploid plants directly. L. Agus Sukamto.<br />Triploid plants are very vigorous and beneficial since they<br />generally produce seedless fruits, bigger flowers, and produce<br />more volume of wood than the diploid counterparts.<br />The triploid plants can be produced by crossing diploid and<br />tetraploid plants, but this method is cumbersome and takes<br />a long time. In vitro culture of endosperm is an alternative<br />method to produce triploid plants directly. The success of<br />endosperm culture is dependent on many factors, such as<br />maturity of endosperm, presence of the zygotic embryo, culture<br />medium, growth regulators, browning, culture period,<br />an plant species. Generally, a mature endosperm needs an<br />initial association with an embryo to induce cell divisions,<br />while proliferation of an immature endosperms is not<br />dependent on the embryo. Endosperm of most parasitic<br />angiosperms shows direct organogenesis without callus<br />formation. Plants produced from endosperm culture are<br />generally triploid, although some plants possess different<br />ploidy levels.</p>

In vitro zygotic embryo culture of Pinus peuce Gris.: Optimization of culture conditions affecting germination and early seedling growth

This study reports a protocol for the germination and early seedling growth of Pinus peuce Gris. using zygotic embryo culture. In order to overcome seed dormancy and optimize organogenesis, the effect of nutritional, plant growth regulatory and physical factors on in vitro germination and growth of isolated mature zygotic embryos of P. peuce were investigated.