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"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 "

"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 ... "

"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."

"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."

"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."

"Analisis Morfologi dan Molekular Padi Transgenik cv. Nipponbare yang Membawa Gen CONSTANS (CO) Terkait Umur Pembungaan. Pembungaan merupakan proses penting yang mengawali produktivitas pada tanaman. Metode rekayasa genetika dengan mengintroduksi gen CONSTANS dari tanaman Arabidopsis thaliana (AtCO) ke dalam tanaman padi kultivar Nipponbare digunakan sebagai upaya peningkatan produksi padi. Gen CO diketahui mampu menginduksi terjadinya pembungaan yang lebih awal pada tanaman. Penelitian bertujuan mengetahui integrasi gen AtCO pada genom padi, pengaruh gen tersebut terhadap waktu pembungaan, dan karakter agronomi pada tanaman padi Nipponbare transgenik generasi T2. Hasil pengamatan morfologi menunjukkan bahwa tanaman padi transgenik cenderung memiliki karakter agronomi lebih baik dibandingkan tanaman padi kontrol, namun tidak menunjukkan waktu pembungaan lebih cepat. Analisis Polymerase Chain Reaction (PCR) menunjukkan 169 dari 227 tanaman padi transgenik memiliki gen hpt dan CO yang terintegrasi ke dalam genom padi.

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Flowering is an important process that initiates plant productivity. Rice (Oryza sativa cv. Nipponbare) was genetically engineered by introducing a CONSTANS (CO) gene from Arabidopsis thaliana (AtCO) to improve rice productivity. The CO gene is a gene responsible for inducing early flowering. The aims of the experiment were to use morphological and molecular analysis to study the integration of the AtCO gene and its influence on agronomic traits in the T2 generation of Nipponbare transgenic AtCO rice. Morphological observations showed that agronomic traits tended to be better in the transgenic plants than in the wild type (controls), although the transgenic plants flowered later than the wild type. Polymerase Chain Reaction (PCR) analysis showed that 169 out of 227 transgenic rice plants showed hpt and CO gene integration."

"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 .."

"Population Structure of Trichogrammatoidea armigera, Egg Parasitoid of Helicoverpa armigera Based on RAPD-PCR Analysis. Bahagiawati, Damayanti Buchari, Nurindah, H. Rizjaani, Dwinita W. Utami, B. Sahari, and A. Sari. Genetic structures of Trichogrammatoidea armigera (Hymenoptera: Trichogrammatidae), the egg parasitoid of Helicoverpa armigera (Lepidoptera: Noctuidae) were studied. Egg masses of H. armigera were collected from fields of several locations in West Java and East Java with different distances among them and two distinct cultural practices, i.e., monoculture and polyculture. Genetic relationships among T. armigera populations that emerged from the collected H. armigera eggs were analysed by the RAPD-PCR technique using four oligonucleotide primers. The four primers revealed 55 presumptive polymorphic loci that were used to estimate the population structures. The estimated values of Fixation Index (Fst) was 0.16, indicating that there was a division of the populations into subpopulations. This Fst value implied the present of reproductive isolation among the populations that might be due to their low migration rate (1.3 insect per generation). This low migration rate indicated the present of low level of gene flow among the populations. A dendrogram resulted from the NTSYS analysis indicated that the West Java and East Java populations of the egg parasitoid had quite wide genetic distances, while within each of the populations there was a subdivision of minor populations. This finding has an important implication on the program to release Trichogramma spp. as a biological control agent. The release of the parasitoid cannot be done randomly, because if we pick up a minor population, the starter or the released population will mate with the local population and multiply, thus the inundation will fail to control the target pest."