Abstract. Fendiyanto MH, Satrio RD, Darmadi D. 2020. Metabolic profiling and pathway analysis in red arillus of Salacca sumatrana demonstrate significant pyruvate, sulfur, and fatty acid metabolisms. Biodiversitas 21: 4361-4368. Salak or snake fruit (Salacca Reinw.; Arecaceae) is a tropical fruit that has high biodiversity in a tropical country such as Indonesia. Several types of salak can be found in Indonesia, one of which is Salacca sumatrana (Becc.) Mogea. Research on profiling metabolites in S. sumatrana has not been conducted. Therefore, the aim of this study was to determine the metabolite profile and pathway analysis in S. sumatrana, especially in red arillus tissue. This research was conducted by the method of gas chromatography-mass spectrometry (GC-MS) and the study of bioinformatics through metabolomics approaches. The results showed that red arillus had metabolites consisting of groups of fatty acids, esters, alcohols, xylene, phenols, etc.. Significant metabolites found were isobutyl acetate, palmitic acid, formic acid, 2-pentanoic acid, ethylic acid, n-hexadecoic acid, hydroxypentanoic acid, etc. There was a tendency that metabolite ethylic acid, identified as C00033 accession, was a key metabolite in either the pyruvate metabolism pathway or sulfur metabolisms with relatively high impact values. Pathway analysis using bioinformatics studies using MetaboAnalyst shows that four of ten pathways detected had a high log-ratio (p)/pathway impact, i.e., pyruvate metabolism, sulfur metabolism, fatty acid biosynthesis, and biosynthesis of unsaturated fatty acids. Thus, pyruvate, sulfur, and fatty acid metabolisms are important pathways in the red arillus of S. sumatrana. This study can be used as a reference in early metabolomic studies on S. sumatrana using GC-MS and the metabolites identified as metabolite markers can be used for plant breeding and biologists to understand the metabolic mechanism of the red arillus tissues from S. sumatrana.

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Abstract. Fendiyanto MH, Satrio RD, Suharsono, Tjahjoleksono A, Miftahudin. 2019. Correlation among Snpb11 markers, root growth, and physiological characters of upland rice under aluminum stress. Biodiversitas 20: 1243-1254. The cultivation of upland rice in acid soils faces aluminum (Al) toxicity. Development of Al-tolerant rice could be one of the solutions to overcome the problem. Marker-assisted breeding to develop Al-tolerant rice requires at least a molecular marker for foreground selection. Snpb11 is a molecular marker developed from the nucleotide differences in a specific allele between Al-tolerant and sensitive rice. Snpb11 has never been used as a molecular marker in rice. Therefore this study aimed to examine the correlation among Snpb11 marker, root growth, and physiological characters under Al stress in upland rice. We used physiological characters and the Snpb11 marker to justify the Al tolerance level in several upland rice varieties. We found that physiological characters, i.e.: primary root length, total root length, chlorophyll, and carotenoid content showed positive correlation to Snpb11. Conversely, root malondialdehyde content, which represents the level of lipid peroxidation showed a negative correlation to Snpb11. There is evidence that the Snpb11 highly correlated with primary and total root length characters, which are the Al tolerance parameters used in rice. Therefore, Snpb11 markers can be used to distinguish the Al tolerance level in upland rice.

The DWARF AND LOW TILLERRING (DLT) gene is a transcription factor for a gene involved in Brassinosteroid (BR) biosynthesis. Manipulating BR biosynthesis will affect the height and tiller number of rice. CRISPR-Cas9 is an accurate tool to edit a gene sequence. The accuracy of site editing of the CRISPR-Cas9-mediated target gene editing is determined by the 20 nucleotide sequences in the sgRNA and the binding site known as the Protospacer Adjacent Motif (PAM). The study aimed to design sgRNA and predict the DLT gene mutation sites in rice cv. Hawara Bunar. The exon 1 of the DLT gene was amplified using a primer pair designed from the reference gene. The PCR product was then sequenced, and the sequence was used to design sgRNA. The study has designed sgRNA located on the targeted sequence that corresponds to the Gras family protein domain of the exon1 DLT gene. The mutation sites were predicted to be at the domain site through the alignment of the nucleotide and amino acid sequences of the DLT gene and the reference gene. It is predicted that mutations in the target site that corresponds to the protein domain will change the protein structure and its function.