Effect of Sucrose on Microtuber Induction and Inulin Accumulation in Jerusalem Artichoke (Helianthus tuberosus L.)

The effect of sucrose concentrations and photoperiod applying on microtuber induction and inulin accumulation of Jerusalem artichoke (Helianthus tuberosus L.) have conducted under in vitro condition. Numbers, lengths and weights of microtubers induced from the single node explants with 0.50 cm above stem node- and stem node- cutting was not significant difference. Concentration of sucrose (51.70, 60, 80, 100 and 108.20 g/l) containing in microtuber induction medium (MST) and photoperiod applying (10.30/13.70, 12/12, 16/8, 20/4 and 21.60/2.40 h light/dark) significant effected to numbers of microtubers (P ≤ 0.05). The optimized sucrose concentration and photoperiod applying for highest numbers of microtubers was 100 g/l and 20/4 h light/dark, respectively. The significant difference of inulin content (P ≤ 0.05) in microtuber induced from various conditions was determined. The microtubers induced on MST medium supplemented with 80 g/l sucrose under 16/8 h light/dark accumulated highest inulin content (324.84 ± 40.78 mg/ g dry weight) when compared with others. Data suggested that sucrose and light duration played role in microtuber induction and inulin accumulation of Jerusalem artichoke. Keywords: Inulin, Jerusalem artichoke, Microtuber, Photoperiod, Sucrose

In vitro Microtuber Induction and Regeneration of Plantlets from Microtuber Discs of Cultivated Potato (Solanum tuberosum L.)

In vitro microtuber induction potential of a popular potato (Solanum tuberosum L.) variety Diamant was examined using different supplements of growth regulators. Results showed that MS supplemented with 4.0 mg/l BAP, 1.0 mg/l IAA and 1.0 mg/l GA3 produced the best response towards microtuber induction from in vitro raised stem cuttings. Further, these in vitro raised microtubers were used to establish a highly efficient shoot regeneration system. Highest number of regenerated shoots were obtained from the peripheral region of microtuber disc explant on the MS containing 4.0 mg/l BAP and 2.0 mg/l IAA. Histological analysis revealed that microtuber periderm was composed of a several layers of uniform meristematic phellogen cells which were responded to growth hormones in the above mentioned medium producing healthy multiple shoots. Effective roots developed from these in vitro raised shoots on half strength of MS with 0.2 mg/l IBA. The plantlets were eventually acclimatized in pots containing soil for their establishment. Plant Tissue Cult. & Biotech. 29(1): 63-72, 2019 (June)

MULTIPLIKASI TUNAS DAN INDUKSI UMBI MIKRO SATOIMO (Colocasia esculenta (L.) Schott) PADA BEBERAPA KONSENTRASI SUKROSA DAN BENZILAMINOPURIN

Taro or Satoimo (Colocasia esculenta (L) Schott var antiquorum) is an alternative of non-rice food. To support saitomo mass cultivation in several regions in Indonesia, shoot multiplication and induction of satoimo microtuber through in vitro technique is amongst the stage to be undertaken. The aims of this study were to determine the effect of BAP (benzylaminopurine) and sucrose for shoot multiplication and microtuber induction of in vitro culture of satoimo. The experiment was arranged in two factors: BAP (0, 1, 2 and 3 mg/L) and sucrose (30, 60, 90 and 120 g/L). The result showed that the single effect of BAP or sucrose and interaction of both significantly increased the number of shoots. The effect of 2 mg/L BAP was more homogeneous than that of 1 and 3 mg/L BAP. Sucrose with the concentration of 30 g/L was the best concentration for shoot multiplication. The highest number of microtuber was achieved with 2 mg/L BAP + 30 g/L sucrose treatments, but tended to decrease due to increasing sucrose concentration. In 2 and 3 mg/L BAP treatments, the number of microtuber increased along with the increasing sucrose concentration.Keywords: satoimo, in vitro shoot, microtuber, benzylaminopurine, sucrose ABSTRAKSatoimo (Colocasia esculenta (L) Schott var antiquorum) merupakan bahan pangan alternatif non-beras. Untuk mendukung produksi massal satoimo di beberapa wilayah di Indonesia, multiplikasi tunas dan induksi umbi mikro secara in vitro merupakan tahapan yang harus dilakukan. Tujuan penelitian ini adalah untuk mengetahui pengaruh BAP dan sukrosa terhadap multiplikasi tunas dan induksi umbi mikro satoimo dalam kultur in vitro. Perlakuan terdiri dari 4 taraf konsentrasi BAP (0, 1, 2 dan 3 mg/L) dan 4 taraf konsentrasi sukrosa (30, 60, 90 dan 120 g/L). Hasil penelitian menunjukkan bahwa BAP dan sukrosa secara tunggal serta interaksinya berpengaruh nyata terhadap multiplikasi tunas in vitro. Pengaruh konsentrasi BAP 2 mg/L lebih homogen dibandingkan perlakuan BAP 1 dan 3 mg/L. Sukrosa 30 g/L merupakan konsentrasi terbaik untuk multiplikasi tunas. Umbi mikro terbanyak terdapat pada perlakuan BAP 1 mg/L + sukrosa 30 g/L tetapi cenderung mengalami penurunan jika konsentrasi sukrosa dinaikkan pada konsentrasi BAP tetap. Pada perlakuan BAP 2 dan 3 mg/L jumlah umbi mikro yang terbentuk cenderung meningkat seiring dengan peningkatan konsentrasi sukrosa.Kata kunci: satoimo, tunas in vitro, umbi mikro, benzilaminopurin, sukrosa

Microtuberization of Potato (Solanum tuberosum) under Saline Stress

In vitro bioassays for screening and selection of salinity (NaCl)-tolerant potato have primarily focused on nodal cuttings. However, the relative tolerance of the microtuberization stage to salinized medium may be more relevant. A two-step microtuberization protocol was used in which in vitro layering was followed by microtuber induction in salinized media. `Norland', `Russet Burbank', and `Superior' shoots were layered in liquid Murashige and Skoog (1962) basal salt medium with 20 g sucrose/liter and incubated for 4 weeks at 25C with 50 μmol–m–2·s–1 photosynthetic photon flux density and 16-h day/8-h night period. Medium was replaced with liquid medium containing 80 g sucrose/liter and NaCl at 0, 80, or 160 mM. Cultures were incubated for 4 weeks at 15C with 50 μmol–m–2–s–1 photosynthetic photon flux density and 8-h day/16-h night period. Relative salinity tolerance of cultivars differed during the microtuberization stage. Low salinity (80 mM) stimulated, but high salinity (160 mM) depressed, microtuber yields compared with controls.