Aims: To isolate and characterize novel bacteriophages infecting the phytopathogen, Ralstonia solanacearum, and to evaluate them as resources with potential uses in the biocontrol of bacterial wilt. Methods and Results: Fourteen phages infecting R. solanacearum were isolated from soil samples collected in Chiang Mai, Thailand. The phages showed different host ranges when tested against 59 R. solanacearum strains isolated from Thailand and Japan. These phages were characterized as nine podoviruses and five myoviruses based on their morphology. Podovirus J2 in combination with another podovirus (φRSB2) lysed host cells very efficiently in contaminated soil. J2 treatment prevented wilting of tomato plants infected with a highly virulent R. solanacearum strain. Conclusions: Treatment with J2 effectively reduced the amount of the bacterial wilt pathogen in contaminated soil and prevented bacterial wilt of tomato in pot experiments. Myovirus J6 possessed jumbo phage features, giving a unique opportunity to study its utilization as a biocontrol agent. Significance and Impact of the Study: As exemplified by J2, the phages isolated in this study represent valuable resources with potential uses in biocontrol of bacterial wilt. A rare jumbo phage J6 served as a valuable subject to understand and utilize this new group of phages.

The study aims to develop a valid, practical and effective Biology student's book based on Science Technology Engineering and Mathematics (STEM) on the topic of biotechnology for Grade XII. The method applied for the study was research and development with the 4-D model. The subjects were 58 Grade XII students of SMAN 1 Muncar, Banyuwangi-Indonesia. The results showed that the average of validation result of STEM-based student's book was 86.4% which fell under a strong valid category. The average percentage of legibility test and practicality were in very good category of 87.18% and 96.53%, respectively. Meanwhile, the average of effectiveness test was 0.77 of normalized gain categorized in high criteria. In conclusion, it could be determined that STEM-based student's book of biotechnology is valid, pratical, and effectively used in learning process.

The genome organization, gene structure, and host range of five podoviruses that infect Ralstonia solanacearum, the causative agent of bacterial wilt disease were characterized. The phages fell into two distinctive groups based on the genome position of the RNA polymerase gene (i.e., T7-type and ϕKMV-type). One-step growth experiments revealed that ϕRSB2 (a T7-like phage) lysed host cells more efficiently with a shorter infection cycle (ca. 60 min corresponding to half the doubling time of the host) than ϕKMV-like phages such as ϕRSB1 (with an infection cycle of ca. 180 min). Co-infection experiments with ϕRSB1 and ϕRSB2 showed that ϕRSB2 always predominated in the phage progeny independent of host strains. Most phages had wide host-ranges and the phage particles usually did not attach to the resistant strains; when occasionally some did, the phage genome was injected into the resistant strain's cytoplasm, as revealed by fluorescence microscopy with SYBR Gold-labeled phage particles.

This study aims to determine the effectiveness of the STEAM (Science, Technology, Engineering, Arts, and Mathematics)-based biotechnology module equipped with flash animation for learning biology in high school. This research was conducted in a high school, involving 32 students of Year XII. The research design was the design model for development of R2D2 with one group pretestposttest design as effectiveness tests. This study utilized a learning design, biotechnology modules equipped with flash animation, instrument testing, validation sheet and questionnaire as research instruments. Data validation and the questionnaire results were then converted into qualitative data into a category. The effectiveness test data were analyzed using the N gain. The results of the validation material, media and users indicated that the module was valid with the final score of 89.85. Students' responses to the module in terms of readability, clarity of presentation, the attractiveness and usefulness of the results were in very good category (81.2%). The effectiveness test showed that result of post-test greater than pre-test and the value of N gain were in the high category (0.72).

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The aim of this research was to assess the classification of science test items of TIMSS grade 8 based on higher order thinking skills (HOTS) and determine whether those classified-science test items can be an assessment tool in science class. Sixteen sample test items of HOTS were chosen from 37 reasoning items of TIMSS 1999, 2003, and 2011; which were 6 of analysing, 6 of evaluating, and 4 of creating. The selected items were tested to 410 ninth grade students in 14 public schools in Jember, Indonesia. Data were analysed by using point-biserial correlation to measure the index of discrimination and degree of difficulty at items of each level of HOTS test. The result revealed that the point-biserial index of discrimination for each item was higher than 0.25. The degree of difficulty of analysing, evaluating and creating test items exhibited a similar trend, which was in good range. Each test item has significant validity. Whilst reliability analysis showed that each test item was acceptable and indicating a high level of internal consistency. In conclusion, the classified science test items of TIMSS are good to use as assessment tools to measure HOTS of students in science class. Keywords: higher order thinking skills, point biserial correlation, science test items.

This research aims to identify the errors of students’ answers in solving the TIMSS cognitive domain of reasoning. This research was a qualitative descriptive research. A total 259 students from four secondary schools located in rural and urban areas in Jember, East Java participated in a paper and pencil test. Error identification was examined by reducing the result of wrong students’ answer and grouping based on error type of general errors. The results showed that the average percentage of total errors from the four schools were contradicting error of 7.3%, disregarding evidence error of 5.2%, misreading error of 45.7%, and opinion-based judgment error of 40.9%. In conclusion, there were four types of general errors made by students in answering TIMMS test item of reasoning domain with misreading and disregarding evidence as the highest and lowest error, respectively.

Penggunaan Virtual Laboratory dapat membantu siswa dalam memahami konsep yang bersifat abstrak. Penelitian ini bertujuan untuk mengembangkan media Virtual Laboratory pada topik kultur jaringan tumbuhan. Jenis penelitian ini adalah penelitian pengembangan (Research and Development). Subjek penelitian ini yaitu siswa kelas XII MIA SMA Negeri 3 Jember (N=39). Model pengembangan yang digunakan adalah model 4D (define, design, develop, disseminate). Hasil penelitian menunjukan tingkat kelayakan Virtual Laboratory yang telah dikembangkan sebesar 84,72% pada aspekateri; 80,73% pada aspek pengembangan bahan ajar; dan 79,73% pada aspek media. Dengan demikian dapat disimpulkan bahwa media Virtual Laboratory yang dikembangkan layak untuk diterapkan dalam pembelajaran serta dapat meningkatkan hasil belajar siswa pada topik kultur jaringan tumbuhan.