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Linkage of 23 Microsatellite Marker on Chromosome 6 and 7 to Downy Mildew Resistance on Maize. Roberdi, Hajrial Aswidinnoor, Asep Setiawan, Sutrisno, Marcia B. Pabendon, and M. Azrai. Downy mildew caused by Peronosclerospora is one of most important maize disease in several countries, including Indonesia. Parental and progenies selection based on conventional breeding is time consuming and laborious. Development of molecular biology produces many DNA markers used for selection, one of them is microsatellite. The aim of this research to identify microsatellite markers associated with downy mildew resistance on maize progeny MR-4 X AMATLCOHS-9-1-1-1-1-1-2-B, on chromosome 6 and 7. This research was consisted of two activities, phenotypic and genotypic analysis. Phenotypic analysis used 175 progenies BC 1 F 2 and both of parents. This analysis included planting of spreading row, inoculums preparation, inoculation of spreader rows, test material planting, inoculation of test material and observation. Genotypic analysis used 175 progenies BC 1 F 1 and both of parents. This analysis included DNA genome isolation, PCR analysis, electrophoresis, gel staining and data scoring. Percentage of downy mildew infections on MR-4 was 76%, while these on AMATLCOHS-9-1-1-1-1-1-2-B was 16%, and on 175 progenies had range from 10.1-100%. Out of 23 SSR, 12 markers could be mapped in chromosome 6 and 11 markers in chromosome 7. QTL analyses showed that chromosome 7 contain one QTL in position between phi082 and phi116I marker as far as 18.6 cM with 2.6 LOD value.

To select a rehabilitation area of coral reefs in Pahat Island within Anambas Islands, this study was conducted to asses coral reefs condition using diver-towed or manta tow surveys and underwater photo transects (UPT). The results of the manta tow surveys showed coral cover dominated by hard corals percentage ranged between 11% and 50% (categories 2 and 3) in the western, northern and southern parts of Pahat Island. Distribution of hard coral percentage with more than 50% (Category 4: 51% - 75% and 5: 76% -100%) was observed in the eastern part of Pahat Island. While results from UPT showed the hard coral percentage of 62.5%, 33.67% and 17% in the eastern, western and northern of Pahat Island, respectively. There are similarities in the results of coral reef cover Obtained by the manta tow and UPT methods. Conclusions, this study recommends western Pahat Island as a good alternative for a rehabilitation site as the coral coverage was in poor condition.

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One of the emerging topics in agriculture is application of biophysical method such as the use of magnetic field (MF) to treat seeds for improved plants production. An experiment has been carried out to determine the effect of MF exposure on sorghum seeds and its subsequent growth in soil. The treatments were different strength of MF (control, 1 mT, 6 mT) and exposure duration (5, 10, 15 min). The magnetically treated seeds showed higher seed germination percentage, vigour index, seed germination index, seedling growth, plant growth and chlorophyll content compared to non-magnetically treated seeds. The best duration of MF exposure was 15 minutes, either at MF strength 1 mT or 6 mT. It is suggested that pre-sowing MF treatment has the potential to improve crop productivity through the enhancement of germination, seedling emergence, and growth of plants.