Induksi Kalus Dan Regenerasi Beberapa Genotipe Gandum (Triticum Aestivum L.) Secara in Vitro

Callus Induction and In Vitro Plant Regeneration ofWheat Genotypes (Triticum aestivum L.). AtmitriSisharmini, Aniversari Apriana, and Sustiprijatno. Developmentof a reliable in vitro plant regeneration procedure forwheat is a prerequisite for its improvement by genetic transformation.The purpose of this study was to obtain methodsof callus induction and regeneration of wheat genotypes.This experiment was conducted at ICABIOGRAD. Immatureembryos from four wheat genotypes, ie Perdix, Naxos Wew,Combi and Fasan were used to induce callus formation andregeneration rate of callus. For the preparation of callusinduction medium, MS-L7 basal medium was supplementedwith combination of growth regulators 2,4 dichlorophenoxyacetic acid (2,4-D) and 4-amino-3,5,6-trichloropicolinic acid(picloram). While, plant regeneration medium was preparedusing MS basal medium supplemented with combination ofthree growth regulators i.e. IAA, BAP and kinetin. The resultsshowed that genotype, in vitro culture medium and growthregulators played a dominant role in callus induction andplantlet regeneration. All the 4 genotypes responded positivelyto callus induction, however, variability was observednot only among the genotypes but also within callusinduction medium used. The best induction medium wasthe MS-L7 basal medium supplemented with combination ofphytohormon 4 mg/l 2,4-D + 2 mg/l picloram (GIK-3) whichshowed 100% callus induction frequency. Whereas, the bestregeneration medium was shown by MS basal medium withcombination of phytohormon 1.5 mg/l BAP dan 0.5 mg/lkinetin (RG3). Regarding plant regeneration, Perdix was themost responsive genotype to be regenerated with regenerationfrequency of 57.33%. The successfully acclimatizedplanlets in greenhouse were obtained from Perdix andNaxos Wew genotypes. These results will potentially facilitategenetic transformation research of wheat in Indonesia

Identifikasi Galur Dan Gen-gen Terkait Toleran Kekeringan Pada Padi Transgenik CV. T309 Yang Mengandung Vektor Penanda Aktivasi

Activation tagging is an efficient tool forfunctional analysis of the rice genes. We have developed anumber of transgenic rice lines (Oryza sativa L. ssp.japonica cv. Taipei 309) containing activation tagging vector.However, the phenotypes and genotypes of these lines, inrelation to the drought stress, have not been analyzed. Theobjectives of this research were to identify transgenic ricelines that showed tolerance to the drought stress and toidentify the genes that may be associated with the droughtstress. The drought stress tolerance in transgenic rice lineswas identified by testing their tolerance to the drought stressand also by detecting the presence of bar and nptII genes.The result showed that 56 out of 59 rice lines were resistantto Basta herbicide and three of them showed tolerance todrought stress, namely PA.T-1.2, PA.T-4.1, and PA.T-5.1 lines.PCR analysis showed that PA.T-1.2 and PA.T-4.1 containedboth hptII and bar genes, while the PA.T-5.1 line containedbar gene only. Thermal Asymetric Interlaced-PCR (TAILPCR)analysis showed that two genes may be asssociatedwith the drought stress tolerance. Those genes areOSJNBa0004120.14 that produces uridylate putative kinaseand OsPPCK2L that produces phosphoenolpyruvatecarboxylase kinase

Respon Padi Transgenik CV. Nipponbare Generasi T1 Yang Mengandung Gen Oryza Sativa Dehydration-response Element Binding 1a (Osdreb1a) Terhadap Cekaman Salinitas [Response of T1 Generation Transgenic Rice CV. Nipponbare Containing an Oryza Sativa Dehydration-response Element Binding 1a (Osdreb1a) Gene to Salinity Stress]

Salinity is one of the abiotic constraints in the cultivation of rice crop. One of the reasons agricultural land becomes saline is due to the intrusion of seawater into the mainland as a result of global climate change. Dehydration-responsive element binding (DREB) gene is a plant -specific transcription factor gene that have important role in regulating plant responses to abiotic stresses, including high salinity. Transgenic rice plants cv. Nipponbare carrying OsDREB1A gene have been generated. However, study of the response of putative transgenic plants to salinity has not been done. The research objective is to study the response of T1 generation Nipponbare-OsDREB1A transgenic rice plants to salinity stress. The result showed that the response of putative transgenic rice Nipponbare-OsDREB1A to salinity stress 25 mM and 150 mM NaCl indicated a level of tolerance varies from highly sensitive to highly tolerance. These variations were possibly occurred because of the segregation state of the T1 generation transgenic rice. Based on damage symptom scoring and PCR analysis provided information that transgenic rice plant cv. Nipponbare-OsDREB1A which showed positive PCR had a very high tolerance to salinity stress 150 mM compared with non-transgenic rice cv. Nipponbare

Construction and Transient Expression of Chimeric Cassettes Containing CaMV 35S or OsAER1 Promoter and GUS Gene Fusion in Tobacco

Reporter gene assays are commonly used to study the expression pattern of a gene and the promoter activity. The purpose of this study was to assemble the chimeric gene constructs consisting of CaMV 35S promoter orOsAER1 gene promoter connected to the β-glucuronidase (GUS) reporter gene encoding the β-glucuronidase enzyme and to obtain an efficient method for Agrobacterium tumefaciens-mediated transient transformation of tobacco sprouts. The CaMV 35S promoter fragment reamplified from pCAMBIA1301 binary vector and the OsAER1 gene promoter fragment amplified from rice cv. Awan Kuning were ligated into pCAMBIA1300int::gus::tNOS to produce binary vectors pCAMBIA1300int::p35S::gus::tNOS and pCAMBIA1300int::prOsAER1::gus::tNOS. The vectors were used for transient transformation of 5–day old tobacco seedlings. The transformation was carried out using two bacterial cultures with densities of OD600 = 0.5 or OD600 = 1.0 combined with a vacuum for 15 or 30 minutes. Tobacco seedlings transformed with pCAMBIA1300int::p35S::gus::tNOS showed higher transformation efficiency as compared tothe ones transformed with pCAMBIA1300int::prOsAER1::gus::tNOS. A higher efficiency was obtained from transformation using bacterial culture with density of OD600 = 0.5 in combination with a vacuum for 30 minutes. Expression of GUS gene in the tobacco sprouts transformed with CaMV 35S promoter construct was observed through out the sprouts area (root, hypocotyl, cotyledon, and leaf), where as expression of GUS gene was observed in root, hypocotyl, and cotyledon, but not in leaf on tobacco sprouts transformed with OsAER1 promoter construct. These results indicate that the transient transformation is a quick and simple method for testing a chimeric gene construct