Hasil Pencarian  ::  Simpan CSV :: Kembali

Abstrak :
Kemuning (Murray a panicxilata (L. ) Jack), yang dikenal sebagai tanaman bias, berpotensi sebagai tanaman obat. Telah dilakukan kultur kalus batang kemuning yang d iper lakiikan dengan kolkisin. Kolkisin merupakan senyawa kimia yang umura d-igunakan untuk merangsang pembentukan sel-sel yang bersifat poliploid pada tanaman. Perlakuan perendaman ujung batang kemuning selama 10 . raenit dalam larutan kolkisin 0, 5, 10, 15, 20, 25 dan 30. /■ ppm, sebelum ditanam pada modifikasi medium MS (1962), dapat merangsang pertumbuhan eksplan hingga membentuk kalus. Pengamatan kualitatif memper1ihatkan terbentuknya kalus berwarna krem dengan tipe "friabel kompak"; dan dari sayatan anatomi kalus setelah dikultur selama 8 minggu memper1ihatkan kecenderungan pembesaran inti sel pada perlakuan 5, 10, 15, 20, dan 25 ppm. Hasil uji Kruskal-Wal lis pada a = 0,05, menunjukkan bahwa kolkisin tidak berpengaruh nyata terhadap berat basah kalus, tetapi berpengaruh nyata terhadajp berat kering kalus. Uji perbandingan berganda pada a = 0,05, menunoukkan bahwa berat kering kalus,dengan perlakuan kolkisin 5, 15 dan 25 ppm berbeda nyata dengan kontrol; sedangkart antar perlakuan % terdapat beda nyata antara perlakuan kolkisin 5 ppm dengan | 20 dan 30 ppm; 15 ppm dengan 30 ppm; serta 25 ppm dengan f- 30 ppm.

Abstrak :
The hypersensitive reaction (HR) jn plants is a plant defense system against pathogen attack. HR is characterized by the rapid death of infected cells accompanying the formation of necrotic lessions in which pathogens are thought to be enclosed. Following the early signaling events activated by pathogen attack, the elicitor signals are often amplified through the generation of secondary signal molecules such as salicylic acid (SA) and Jasmonate acid (JA). Some studies have shown thai SA- and JA-signaling pathways are interconnected in complicated ways and it is still not clear how defense response is modulated by SA and JA. To understand better the involvement of JA. the action of MeJA on harpin-induced HR was investigated by using tobacco plant (wildtype and transgenic carrying a chimeric gene of PSPAL2 promoter and GUS gene. Leaves of of tobacco were infiltrated with harpin and MeJA. The results from HR assay and GUS histochemical staining showed that induction of HR by harpin (250 ug/ml) seems to be modulated by 100 uM MeJA. These results suggest that exogenenously application of MeJA will affect the endogenous concentration in plant that will become a switching point for MeJA to lead the potentiation or suppression of defense response.