Penapisan Kapang Asal Lahan Sulfat Masam Kalimantan Selatan Sebagai Penghasil Enzim Ekstraseluler

Kalimantan acid sulphate land has the potential to be developed into productive land, with good land optimization. Utilization of rhizosphere microorganism diversity, especially mold can potentially provide a solution in optimizing agricultural land, namely the ability to produce extracellular enzymes. This study aims to determine the potential of mold originating from acid sulphate fields in producing extracellular enzymes (pectinase, chitinase, glucanase, cellulase, and phosphatase). The study was conducted in June-July 2019 at the Microbiology Laboratory, Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development. Screening  of extracellular enzyme-producing fungi was carried out on selection media. The results obtained by some isolates have the ability to produce extracellular enzymes. Indications of the ability of mold to produce extracellular enzymes are the presence of clear zones in the selection medium. In pectinase, chitinase and glucanase testing all isolates showed negative results. Potential isolates in producing extracellular enzymes include Penicillium sp. Paddy 4.1 (cellulolytic index 2.43),  Clonostachys sp. KRMT 17.9 and Penicillium singorense KLK 13.7 (proteolytic indices 3.97 and 3,00, respectively). The difference in index values ​​indicates the variation in the level of enzyme activity.Lahan sulfat masam kalimantan berpotensi untuk dikembangkan menjadi lahan yang produktif, dengan pengoptimalan lahan yang baik. Pemanfaatan keanekaragaman mikroorganisme rhizosfer, khususnya kapang dapat berpotensi memberikan solusi dalam pengoptimalan lahan pertanian, yaitu dengan kemampuan menghasilkan enzim-enzim ekstraseluler. Penelitian ini bertujuan untuk mengetahui potensi kapang asal lahan sulfat masam dalam menghasilkan enzim extraseluler (pektinase, kitinase, glukanase, selulase, dan fosfatase). Penelitian dilakukan pada bulan Juni-Juli 2019 di Laboratorium Mikrobiologi, Balai Besar Penelitian dan Pengembangan Bioteknologi dan Sumberdaya Genetik Pertanian, Bogor. Penapisan kapang penghasil enzim ekstraseluler dilakukan pada media  seleksi. Hasil penelitian diperoleh beberapa isolat memiliki kemampuan dalam menghasilkan enzim ekstraseluler. Indikasi adanya kemampuan kapang dalam menghasilkan enzim ekstraseluler yaitu adanya zona bening pada medium seleksi. Pada pengujian pektinase, kitinase dan glukanase semua isolat menunjukan hasil yang negatif. Isolat yang potensial dalam menghasilkan enzim ekstraseluler diantaranya Penicillium sp. Padi 4.1 (indeks selulolitik 2.43),  Clonostachys sp. KRMT 17.9 dan  Penicillium singorense KLK 13.7 (masing-masing indeks proteolitik 3.97 dan 3,00). Perbedaan nilai indeks menunjukan adanya variasi tingkat aktivitas enzim. &nbsp

<i>In vitro</i> Embryogenesis Derived from Shoot Tips in Mass Propagation of Two Selected-Clones of <i>Phalaenopsis</i>

Phalaenopsis is of high economic value and market demand in Indonesia; however, orchid products are mostly imported from other countries. ‘Kristina Dwi’ (KD) 69.274 and ‘Dedeh’ (D) 802.28 are two selected clones with high potential utilized and developed commercially. To support their commercialization, a reliable in vitro propagation protocol is essential.  In the current study, an in vitro mass propagation protocol for KD 69.274 and D 802.28 clones was successfully established using shoot tips as explant sources. A high number of embryos, up to 8.2 embryos per explant, with 58.5% explant regeneration, and 3.5 regenerated-explants in average were regenerated from shoot tips of KD 69.274 clone cultured on  half-strength Murashige and Skoog (MS) medium, with full strength micro, Fe-chellate and vitamin containing 0.5 mg/L thidiazuruon (TDZ) and 0.25 mg/L N6-benzyladenine (BA). The initial embryos were proliferated by culturing embryos individually on half-strength MS medium with 0.13 mg/L TDZ and 0.25 mg/L BA and resulted in high embryo regeneration up to 91.4%, with 10.2 embryos per explant and no embryo browning. The embryos were multiplied under periodical subcultures of 3 months each, resulting in gradual increasing number of embryos from the first subculture till the fifth subculture, with 23.6 embryos produced, then declined afterward. The embryos were easily germinated on half-strength MS medium with full strength of vitamin and hormone free, with 73.9% embryo germination and 14.9 germinated embryos. Healthy plantlets were stimulated on the same medium with 2 g/L activated charcoal (AC) and successfully acclimatized on Cycas rumphii bulk, with 88.3% survival plantlets. Finally, it can be summarized that a new in vitro mass propagation protocol, as new alternative choice for Phalaenopsis propagation, was successfully established