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"Information on genetic divergence of inbred lines and performance of the hybrids developed from the lines is a great value in maize hybrid program. A study was conducted to evaluate genetic diversity of six QPM and five normal maize inbred lines, to determine the relationship between genetic distance based on SSR markers and the grain yield of single cross hybrid, and to get information promising hybrid from the single cross of QPM hybrid. Twenty four polymorphic primers that covered the 10 maize chromosomes were used to fingerprint the lines, detecting in 94 alleles (average of 3.9 and a range of 2-6 alleles per locus). Genetic divergences were determined using the Jaccard’s similarity coefficient, and a dendrogram was constructed using the UPGMA. Cluster analysis divided the inbreds into two clusters that were confirmed by principal coordinate analysis. Two promising QPM hybrids that are crossed from different heterotic group were found. The estimated value of simple correlations (r) of GDs with the gain yield of single cross hybrid was negatif (-0.07). There is a need to conduct more field trials to obtain more accurate correlations, particularly in a practical utility for predicting maize hybrid performance for grain yield."

"Genetic Diversity of Rice Blast Fungus Pyricularia oryzae Based on a Specific Primer Pot-2 (Rep-PCR). Tasliah, Reflinur, and Masdiar Bustamam. Rice blast (Pyricularia oryzae) is one of the most important diseases of rice. It can be very destructive in the field, when the environmental conditions are favourable. Information on genetic diversity of this pathogen could assist plant breeders in determining strategy for a successful control of the disease. This study was conducted to analyze genetic diversity in P. oryzae isolates by a pair of Pot-2 primers using the rep-PCR technique. These primers were designed from a transposon element of the entire blast fungus genomic DNA. DNA samples were extracted from 212 isolates of P. oryzae collected from two endemic areas of the disease in Indonesia, i.e., Tamanbogo, Lampung, and Sukabumi, West Java, as well as from some non-endemic areas in North Sumatra and West Sumatra). Results of the study indicated that the 212 isolates could clustered into 21 haplotypes. The most dominant haplotypes as indicated by their highest frequency of haplotypes were haplotype Pot 2-019 (54.46%) followed by haplotype Pot 2-021 (14.73%) and haplotipe Pot 2-016 (6.25%). Regardless of origins of the P. oryzae isolates, we found 6 haplotypes from Tamanbogo (out of 117 samples), 13 haplotypes from Sukabumi (out of 77 samples), and 11 haplotypes from North Sumatra and West Sumatra (out of 18 isolates). It seems that genetic diversity of the P. oryzae isolates was not affected by the total number of samples/isolates, but rather by place of the origin and rice genotypes from which the isolates were collected."

"Improvement of Plant Genetic Variability through Soma- clonal Variations. Sri Hutami, Ika Mariska, and Yati Supriati. High genetic variability’s are important factors in the development of new crop varieties. In vitro techniques are applicable for development of crop variability that is not found in the gene pool. One of the in vitro techniques that can be used for this purpose is the somaclonal variation technique. Somaclonal variation may be derived from gen- etic variations in explants and genetic variations in tissue cultures. Variations in the explant may be obtained from cell mutations or polysomic mutations of a certain tissue. Gen- etic variations in tissue culture may be caused by ploidy of chromosomes (endomitosis fusion), changes of chromosom structures (crossings), as well as changes of genes and cyto- plasms. Changes of genetic characters may be improved if anorganic compound was added into the medium. To im- prove the plant tolerances to biotic or abiotic factors, selec- tion components may also be added to the medium. Re- search results showed that somaclonal variation in tissue culture can improve genetic variations in plants. The vari- ation produced in tissue culture provide chances to develop new plant genotipes. Many selection components, such as Gamma-ray irradiation, Al contents and low pH, pure toxin or filtrate, polyethylene glycol (PEG), and plant growth regula- tors can be used to improve somaclonal variations in many plants to produce new genotipes."

"Agarwood or gaharu is a plant that has a high economic value in Asia, due to its use for production of incense and traditional medicines. The agarwood formation occurs in the trunk and roots of trees that have been infected by a fungus, such as acremonium spp ... "

"Callus Induction and Plant Regeneration of Four Rice Varieties through In Vitro Culture. Ragapadmi Purnamaningsih. A study was conducted at the Tissue Culture Laboratory of ICABIOGRAD, Bogor, to obtain an optimum medium formulation for calli regenerations of for rice varities (Ciherang, Cisadane, IR64, and T-309). The research activities were done in five steps, i.e., callus induction, callus regeneration, shoot multiplication, root formation, and plant acclimatization. The type of explants used in the study was embriozygotic explants. Five media formulations were used for the callus induction, while four media formulations were used for the callus regeneration. The results showed that the best medium formulation for induction of callus formation was MS + 2,4-D 2 mg/l + casein hidrolisat 3 mg/l, while the best medium formulation for callus regeneration was MS + BA 3 mg/l "

"Pruatjan (Pimpinella pruatjan Molk.) is an Indonesian medicinal plant which is categorized as endangered plant and included in Appendix I based on CITES. The in vitro conservation techniques have been studied. However, the storage period was very short (4 months) when plant growth retardant and media dilution were applied. Beside that, the residual effect of growth retardant was strong enough so that it needed more than 4 months for recovery. Thus, the use of certain carbon source may prolong the preservation period with shorter time for recovery. The objective of the study was to know the effects of carbon sources (sucrose and mannitol) and culture conditions (culture room and growth chamber) to the growth of pruatjan cultures. This application was hoped to prolong preservation period of pruatjan longer than 4 months and to cut the recovery period after presservation. The study was conducted at Tissue Culture Laboratory in Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development from August 2006 to July 2007. The activities included propagation of in vitro shoot grown in vitro as explants source, preservation of in vitro shoots of pruatjan, and regeneration of the cultures after preservation. The experiment was designed as factorial in Randomized Completely Block Design with 6 replications. The DKW basal media containing 1 ppm BA, 0.2 ppm thidiazuron, and 100 ppm arginine were supplemented with mannitol or sucrose at the level of 1, 2, 3, 4, and 5%. The observed variables were total number of leaves, number of shoot, and number of wilt leaves. The result revealed that pruatjan cultures could be stored longer than 4 months. Generally, the effect of mannitol or sucrose was more dominant than that of cultures condition. The mannitol (1-5%) strongly inhibited the growth of pruatjan cultures so that only a few cultures survived at 7 months preservation period and needed about 1 month for recovery. On the contrary, the effect of sucrose (at the same level) was better than mannitol. The 2.5% sucrose optimally inhibited pruatjan cultures. At that condition, the cultures could be stored for 10 months withoutmorphological changes so that they could recover spontaneously."

"Detection of multiplex microsatellite markers in a single capillary array on a laser detection system is traditionally conducted with specific primers that are labelled with fluorescent dyes. An alternative method using fluorescent labels that are appended to 5' end of universal primer M13 instead of to the specific primers offers flexibility in designning multiplex panels and a less expensive method ... "

"Microsatellite Marker-based Genetic Characterization of Indonesian Maize Inbred Collections. Marcia B. Pabendon, M. Dahlan, Sutrisno, and M. L. C. George. Information on genetic relationships among available crop germplasm such as maize inbred lines, has important implications to breeding programs. A set of 26 maize inbreds togeher with six standard lines from CIMMYT (CML51, CML292, CML202, CML206, CML236, dan CML396), was characterized using 26 SSR markers, which were coverage of the maize genomes. The objective of this study was to analyze genetic diversities among the Indonesian maize inbred collections. Polymorphism Information Content (PIC) value and the observed genetic distance indicated the existence of large variabilities among the inbreds. Cluster analysis based on 27% of the Jaccard’s similarity coefficient placed the inbreds into three groups. Genetic distances among all the possible pairs without the standard maize lines varied from 0.32 (KSX360F2-5-1-3-1v vs KSX2601F2-5-1-1-v) to 0.88 (PT963298-1-B-B-Bv vs Mr13). Cluster and Principal Coordinate Analysis of the genetic distances, revealed a clear differentiation of the inbred lines into groups according to their source populations. This clustering were consistent with those of the known pedigree records of the inbreds based on their morphological characters. These results support the use of morphological traits in the production of maize hybrids. The SSR markers proved to be effective to characterize, identify, and demonstrate genetic similarities among the maize inbred lines."

"Genetic parameters of bisma maize population under different levels of fertilizer application. I. Additive-dominant variance of grain yield. Sutoro, Abdul Bari, Subandi, and Sudirman Yahya. New maize varieties could be obtained through improvement of their plant populations. The method used in selection in the crop improvement was based on values of their genetic parameters. Bisma is one of the maize varieties that has a broad genetic background. New maize varieties be obtained by improving their population through selection under different environmental conditions. Genetic parameter value were estimated by conducting an experiment under NCD II crossing at Bogor. Twenty seven sets, which were developed from three females and three males of S1 as parents of each set, were evaluated under three different fertilization schemes. Results of the experiment showed that the additive genetic variance was significanlty different from zero, and so among the different levels of fertilizer applications .."

"Cell suspension culture could be defined as a process that allows rapidly dividing homogeneous suspension of cells to grow in liquid nutrient media. there are two main types of suspension cultures: (1) Batch cultures in which cells are nurtured in a fixed volume of medium until growth ceases and (2) continuous cultures in which cell growth is maintained by continuous replenishment of sterile nutrient media ... "