<![CDATA[Lahan kritis berkapur, karst, memberikan cekaman abiotik pada tanaman karena hambatan hidrasi dan nutrisi. Asam absisat (ABA) adalah hormon yang diekspresikan tumbuhan pada kondisi cekaman abiotik. CmBG1 merupakan salah satu gen peregulasi hormon ABA pada melon yang akan terakumulasi saat tumbuhan mengalami cekaman. Tujuan penelitian ini adalah mendeskripsikan pengaruh lahan kritis karst terhadap ekspresi gen CmBG1 secara kualitatif dan kuantitatif melon hasil turunan kultivar TACAPA, yaitu kultivar PT dan AT yang ditanam pada medium tanah karst dari wilayah Agroekosistem II dan III Yogyakarta (Gunungsewu, Dlingo, maupun Sentolo). cDNA library diperoleh dari reverse transcription isolat RNA. cDNA diamplifi kasi dengan primer spesifi k, kemudian dispektrofotometri pada λ260 nm untuk mengetahui konsentrasi gen CmBG1. Ekspresi gen dianalisis dengan real time PCR dengan gen referensi Cm-actin. Uji kualitatif dilakukan dengan elektroforesis gel agarosa 1,5%. Hasil penelitian menunjukkan gen CmBG1 terdeteksi dengan ukuran ±1258 bp pada kultivar PT dan AT. Konsentrasi gen CmBG1 melalui spektrofotometri menunjukkan semua kultivar yang ditanam pada media kontrol memiliki konsentrasi yang lebih rendah bila dibandingkan media tanam dengan perlakuan lahan kritis baik Gunungsewu, Dlingo, maupun Sentolo. Hasil ini sama dengan uji ekspresi gen CmBG1 menggunakan analisis kuantitatif real time PCR. Karsts critical land gives abiotic stresses in plants because of hydration and nutrition disturbances. Abscisic acid (ABA) is a hormone that expressed in the plant in abiotic stress conditions. CmBG1 is one of the regulatory genes encoding hormone ABA in melon plants which is accumulated in stress condition. The purpose of this study was to describe the infl uence of karsts critical land on the genes expression of CmBG1 melon cultivars PT and AT qualitatively and quantitatively. The plants were grown in medium karst land of Agroecosystems II and III of Yogyakarta (Gunungsewu, Dlingo, and Sentolo). Total RNA was extracted from leaf tissue then Reversed Transcriptase (RT-PCR) to collect cDNA library. cDNA was amplifi ed using specifi c primer. Spectrophotometry was conducted in λ260 nm and electrophoresis run in 1.5% agarose gel. Control band and reference gene chosen in Real Time PCR was Cm-Actin. CmBGI band (± 1258 bp) was showed both on PT and AT. Cm-actin was showed band of DNA as ± 445 bp. CmBGI gene concentration in critical land medium treatment which is given greater stress on melons are higher than normal condition. This suggests that the CmBGI gene is expressed more in cultivar PT and AT melons when they are grown under stress condition. This result show similarly when using real time PCR.]]>
