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 Regeneration of Triploid Plants of Euonymus alatus ‘Compactus’ (Burning Bush) from Endosperm Tissues

Euonymus alatus (Thunb.) Sieb., commonly known as “burning bush,” is an extremely popular landscape plant in the United States as a result of its brilliant showy red leaves in fall. However, E. alatus is also seriously invasive because of its prolific seed production and effective seed dispersal by birds. Thus, development of sterile, non-invasive, seedless triploid E. alatus is in high demand. In this article, we report successful production of triploid E. alatus using endosperm tissues as explants. In our study, ≈50% of immature endosperm explants and 14% of mature endosperm explants formed compact, green calli after culture in the dark for 8 weeks and then under light for 4 weeks on Murashige and Skoog (MS) medium supplemented with 2.2 μM BA and 2.7 μM α-naphthaleneacetic acid (NAA). Approximately 5.6% of the immature endosperm-derived calli and 13.4% of mature endosperm-derived calli initiated shoots within 8 weeks after they were cultured on MS medium with 4.4 μM benzyladenine (BA) and 0.5 μM indole-3-butyric acid (IBA). Eighty-five percent of shoots rooted after culture on woody plant medium (WPM) containing 4.9 μM IBA for 2 weeks and then on hormone-free WPM medium containing 2.0 g·L−1 activated charcoal for 4 weeks. Eight independently regenerated triploid plants have been identified. Triploid plant regeneration rates observed were 0.42% from immature endosperm explants and 0.34% from mature endosperm explants, respectively, based on the number of endosperm explants cultured. Because triploid plants cannot produce viable seeds, and thus are sterile and non-invasive, some triploid E. alatus plant lines reported here can be used to replace the currently used invasive counterparts. Chemical names used: benzyladenine (BA), indole-3-butyric acid (IBA), and α-naphthaleneacetic acid (NAA).