Pengaruh Cekaman Aluminium terhadap Kandungan Asam Organik dalam Kalus dan Pinak Tomat (Lycopersicon esculentum Mill.)

<p class="p1">The purpose of this research was to evaluate the effects of Al stress on citric, malic and oxalic acid content of <em>L. esculentum </em>cv. Intan callus and plantlet, also aluminum content of <em>L. esculentum </em>plantlet. Callus was induced from cotyledone of <em>L. </em><em>esculentum </em>on Murashige &amp; Skoog (MS) media containing 10<span class="s1">-7 </span>M NAA and 10<span class="s1">-6 </span>kinetin. The callus was then transferred step wisely at 3 weeks interval to media containing 220, 275, 330, 385, 440, 550, 825, and 1100 μM AlCl<span class="s1">3</span>. The callus cultures on the control media and media with the addition of 550 μM AlCl<span class="s1">3 </span>were able to regenerate and produce shoots after 8 passages of subculture. The shoots from media with the addition of 550 μM AlCl<span class="s1">3 </span>were transferred into the media with addition of 825 μM AlCl<span class="s1">3</span>, then to the media with 1100 μM AlCl<span class="s1">3</span>. The High Pressure Liquid Chromatography (HPLC) analysis showed that Al stress callus and plantlets contained malic acid, but no citric and oxalic acid. The content of malic acid in callus decreased with increasing AlCl<span class="s1">3 </span>concentration from 0 to 385 μM. On the other hand, the content of malic acid in callus increased with increasing AlCl<span class="s1">3 </span>concentration from 440 μM to 1100 μM. Similarly, the content of malic acid in root increased with increasing concentration of AlCl<span class="s1">3 </span>from 550 μM to 1100 μM. The result of Neutron Activation Analysis showed that Al content in root decreased as the amount of AlCl<span class="s1">3 </span>increased in the media. These results suggested that <em>L. esculentum </em>callus and plantlet respond to the Al stress by producing higher amount of malic acid.</p>