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BackgroundSystemic acquired resistance (SAR) is induced in non-inoculated leaves following infection with certain pathogenic strains. SAR is effective against many pathogens. Salicylic acid (SA) is a signaling molecule of the SAR pathway. The development of SAR is associated with the induction of pathogenesis related (PR) genes. Arabidopsis non-expressor of PR1 (NPR1) is a regulatory gene of the SA signal pathway [1-3]. SAR in soybean was first reported following infection with Colletotrichum trancatum that causes anthracnose disease. We investigated if SAR in soybean is regulated by a pathway, similar to the one characterized in Arabidopsis.ResultsPathogenesis-related gene GmPR1 is induced following treatment of soybean plants with the SAR inducer, 2,6-dichloroisonicotinic acid (INA) or infection with the oomycete pathogen, Phytophthora sojae. In P. sojae-infected plants, SAR was induced against the bacterial pathogen, Pseudomonas syringae pv. glycinea. Soybean GmNPR1-1 and GmNPR1-2 genes showed high identities to Arabidopsis NPR1. They showed similar expression patterns among the organs, studied in this investigation. GmNPR1-1 and GmNPR1-2 are the only soybean homologues of NPR1and are located in homoeologous regions. In GmNPR1-1 and GmNPR1-2 transformed Arabidopsis npr1-1 mutant plants, SAR markers: (i) PR-1 was induced following INA treatment and (ii) BGL2 following infection with Pseudomonas syringae pv. tomato (Pst), and SAR was induced following Pst infection. Of the five cysteine residues, Cys82, Cys150, Cys155, Cys160, and Cys216 involved in oligomer-monomer transition in NPR1, Cys216 in GmNPR1-1 and GmNPR1-2 proteins was substituted to Ser and Leu, respectively.ConclusionComplementation analyses in Arabidopsis npr1-1 mutants revealed that homoeologous GmNPR1-1 and GmNPR1-2 genes are orthologous to Arabidopsis NPR1. Therefore, SAR pathway in soybean is most likely regulated by GmNPR1 genes. Substitution of Cys216 residue, essential for oligomer-monomer transition of Arabidopsis NPR1, with Ser and Leu residues in GmNPR1-1 and GmNPR1-2, respectively, suggested that there may be differences between the regulatory mechanisms of GmNPR1 and Arabidopsis NPR proteins.

process (FLIP), genes (Koornneef et al., 1998; Levy and Dean, 1998; Piñ eiro and Coupland, 1998). Flowering Time of flowering is a quantitatively inherited character of agrotime genes are those that display major effects on the nomic importance in soybean [Glycine max (L.) Merr.]. The genetics duration of vegetative development. These genes act of flowering time has been extensively studied in the model plant before FLIP genes and may activate or repress floral Arabidopsis thaliana (L.) Heynh. The first objective of this study was to map onto the soybean genetic map orthologous genes known I.M. Tasma,

Potato is one of high economically horticultural plant. The increasing of national consumption of potato becomes a challenge for potato breeders. The success of breeding programs is depending on availability of genetic diversity. The aim of this research was to analyze the genetic diversity of fourteen accessions of potato by using SSR and STS markers. PCR analysis was scored as biner data and the collected data was analyzed using NTSYS and PowerMarker. The result showed that there were 63% polymorphic (12 markers) of total markers. As many as 60 alleles with the size of 200-500 bp were identified by a range of 2-9 alleles per locus. The polymorphism level was 0.59 (0.36-0.74). Result also showed the average of major allele frequency was 49.42% (35.71-63.64%). Nine markers which have polymorphism level more than 0.5 could be used to detect genetic diversity of potato. The average of genetic diversity index was 0.65. Cluster analysis showed that 14 accessions of potato were split in two groups (coefficient 0.70). The first groups consisted of Atlantik, GM 05, Granola Kembang Merbabu 17, and the second groups consist of Repita, Maglia, Medians, CIP397078.7, CIP392781.1, Margahayu, Granola, CIP394613.139, Amabile, and Tenggo. The information of genetic diversity of this germplasm could be used as a preliminary basis for choosing crossing parents in potato breeding in Indonesia.Keywords: Potato (Solanum tuberosum L.), SSR, STS, genetic diversity. ABSTRAKKentang (Solanum tuberosum L.) merupakan salah satu tanaman hortikultura yang memiliki nilai ekonomis tinggi. Meningkatnya kebutuhan konsumsi kentang nasional menjadi tantangan bagi pemulia kentang. Tersedianya sumber keragaman genetika merupakan prasyarat keberhasilan program pemuliaan suatu varietas. Penelitian ini bertujuan menganalisis keragaman genetika empat belas aksesi kentang menggunakan marka simple sequence repeats (SSR) dan sequence-tagged sites (STS). Hasil analisis polymerase chain reaction (PCR) diberi skor sebagai data biner. Analisis data dilakukan menggunakan perangkat lunak NTSYS dan PowerMarker. Hasil penelitian menunjukkan dari 19 marka yang digunakan terdapat 12 marka (63%) yang bersifat polimorfik. Sebanyak 60 alel berukuran antara 200-500 bp dengan kisaran 2-9 alel per lokus berhasil dideteksi. Nilai polymorphic information content (PIC) menunjukkan rerata sebesar 0,59 dengan nilai tertinggi 0,74 (RGH-SSR 21) dan nilai terendah 0,36 (RGH-SSR 30). Rerata frekuensi alel utama adalah 49,42% dengan nilai terendah 35,71% (STG-0016) dan nilai tertinggi 63,64% (RGH-SSR 40). Terdapat 9 marka dengan nilai PIC >0,5 yang dapat digunakan untuk mendeteksi keragaman genetika aksesi kentang. Keragaman aksesi kentang tersebut cukup tinggi, seperti yang direfleksikan oleh nilai rerata diversitas gen, yaitu 0,65. Hasil analisis klaster menunjukkan bahwa keempat belas aksesi kentang tersebut mengelompok menjadi dua kelompok utama pada koefisien 0,70. Kelompok pertama terdiri atas varietas Atlantik, GM 05, Granola Kembang, dan Merbabu 17, sedangkan kelomp...

Stem and root rot caused by the oomycete pathogen, Phytophthora sojae, is a serious soybean disease. Use of Phytophthora resistance genes (Rps) in soybean cultivars has been very effective in controlling this pathogen. Resistance encoded by Rps genes is manifested through activation of defense responses. In order to identify candidate signaling genes involved in the expression of Phytophthora resistance in soybean, a cDNA library was prepared from infected etiolated hypocotyl tissues of a Phytophthora resistant soybean cultivar harvested 2 and 4 h following P. sojae inoculation. In silico subtraction of 101,833 expressed sequence tags (ESTs) originating from unstressed cDNA libraries from 4,737 ESTs of this library resulted in identification of 204 genes that were absent in the unstressed libraries. Of the 204 identified genes, seven were P. sojae genes. Putative function of 91 of the 204 genes could not be assigned based on sequence comparison. Macroarray analyses of all 204 genes led to identification of 60 genes including 15 signaling-related soybean genes and three P. sojae genes, transcripts of which were induced twofold in P. sojae-infected tissues as compared to that in water controls. Eight soybean genes were down-regulated twofold following P. sojae infection as compared to water controls. Differential expression of a few selected genes was confirmed by conducting Northern and RT-PCR analyses. We have shown that two putative regulators of chromosome condensation 1 (RCC1) family proteins were down-regulated in the incompatible interaction. This observation suggested that the nucleocytoplasmic transport function for trafficking protein and non-coding RNA is suppressed during expression of race-specific Phytophthora resistance. Characterization of a cDNA library generated from tissues harvested almost immediately following P. sojae-infection of a resistant cultivar allowed us to identify many candidate signaling genes that are presumably involved in regulating the expression of defense-related pathways for expression of Phytophthora resistance in soybean.

Soybean is an important crop in Indonesia and its consumption has consistently surpassed local production in recent times. As the average yield is relatively low, a more efficient breeding programme that utilizes the latest technological developments in DNA analysis is required. To provide a genomic data resource for future breeding programmes, in this study, wholegenome sequencing was performed for five Indonesian soybean varieties, with an average sequencing depth of 34 reads. Comparison of these sequences with the Williams 82 reference sequence revealed 3,150,869 DNA variations, which averages to one variation in every 308 bases. Comparison of these variations with known single-nucleotide polymorphisms (SNPs) in the SoyKB database revealed that approximately 29% of them were novel SNPs unique to the Indonesian cultivars. Variations found within exons totalled 95,154. Of these, 57,171 were capable of causing mutations that would modify the amino-acid composition of the encoded proteins (nonsynonymous mutations). Phylogenetic analysis using a subset of these SNP data indicated that the cultivars had genetic similarities to landraces from China and Japan, which could provide clues to the origin of soybeans that were introduced into Indonesia.

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<p>Keracunan aluminium merupakan salah satu<br />kendala utama dalam budidaya kedelai pada lahan masam.<br />Pembentukan populasi F2 merupakan langkah awal yang<br />menentukan keberhasilan program pemuliaan tanaman. Tujuan<br />penelitian ini untuk membentuk dan mengkarakterisasi<br />populasi F2 hasil persilangan tetua toleran dan tetua peka<br />keracunan Al. Pembentukan populasi dilakukan menggunakan<br />bantuan marka SSR. Dengan marka SSR populasi dapat<br />dibentuk dengan cepat, akurat, dan efisien. Skrining genotipa<br />kedelai pada tanah masam kahat hara menghasilkan dua<br />genotipa toleran dan dua peka. Empat persilangan tunggal<br />dibuat untuk mendapatkan benih F1. Tanaman F1 dan F2 diidentifikasi<br />menggunakam marka SSR Satt_070. Dua populasi<br />(B3462 X B3293 dan B3462 X B3442) dipilih berdasarkan<br />superiotas fenotipa pada lahan masam dan karakteristik molekuler<br />pasangan tetua. Karakterisasi kedua populasi di lapang<br />menunjukkan transgresiveness luas untuk karakter reproduksi<br />seperti jumlah polong dan berat 100 biji. Ini mengindikasikan<br />bahwa karakter penting lain selain karakter ketahanan<br />terhadap keracunan Al potensial untuk dipetakan<br />dari populasi ini. Metoda pembentukan populasi ini akan sangat<br />bermanfaat bagi pemulia tanaman khususnya pemulia<br />kedelai untuk meningkatkan efisiensi program pemuliaan<br />ketahanan terhadap keracunan Al.</p>