58 research outputs found
Toleransi Tembakau Transgenik Yang Mengekspresikan Gen P5cs Terhadap Stres Kekeringan
Tolerance of Transgenic Tobacco Expressing P5CS Gene Against Drought Stress. Drought is majorosmotic stress that dramatically limit plant growth and productivity. Proline accumulation has been correlatedwith tolerance to drought stress in plants. Therefore, overproduction of proline in plants may lead to increasedtolerance against these abiotic stresses. The objectives of this experiment were to determine the effects of droughtstress at the period of 15 – 90 days after planting (DAP) on growth of T1 plants derived from transgenic GStobacco, to evaluate their tolerance against drought stress, and to determine their leaf proline content. One groupof the tobacco plants were grown in plastic pots and subjected to stress condition during the period of 15 – 90DAP. The other group was grown optimally in plastic pot up to harvest period. All tobacco plants were harvestedat 91 DAP. Leaf proline content was determined at 63 DAP (after six periods of stress). The results indicatedreduced plant height, shoot diameter, leaf number, leaf dry weight and leaf area of all tobacco plants. Stresssensitivity index calculated using leaf dry weight character grouped T1 plants derived from P5CS transgenicGS tobacco into tolerance, medium tolerance and sensitive against drought stress while that of non-transgenicGS tobacco were only medium tolerance and sensitive against drought stress. Higher leaf proline content underdrought stress was observed in all T1 plants derived from P5CS transgenic tobacco than that of non-transgenicGS tobacco. These data demonstrated that proline accumulation as an osmoprotectant and that over-expressionP5CS gene results in the increased tolerance to osmotic stress in T1 plants derived from P5CS transgenic tobacco.Key words: Proline biosynthesis, proline accumulation, sensitivity index, biomass yield Stres kekeringan merupakan masalah utama stres osmotik yang dapat menjadi faktor pembataspertumbuhan dan produktivitas tanaman. Akumulasi prolina berkorelasi dengan tingkat toleransi tanamanterhadap stres kekeringan. Oleh karena itu over-produksi prolina diduga dapat meningkatkan toleransi tanamanterhadap stres kekeringan. Tujuan penelitian ini adalah (1) untuk mengevaluasi pengaruh stres kekeringanmelalui pengurangan air terhadap pertumbuhan dan hasil tanaman TI zuriat dari tembakau GS transgenik P5CSgenerasi TO, (2) menganalisis akumulasi prolina daun tanaman TI zurlat dari tembakau GS transgenik P5CSgenerasi TO kondisi stres dan non-stres, serta (3) menganalisis hubungan antara akumulasi prolina daun padakondisi stres kekeringan dengan pertumbuhan dan hasil tanaman. Percobaan dua faktor (tembakau transgenikstres kekeringan) disusun dengan rancangan acak kelompok. Sebagian tanaman yang diuji disiram setiap hari hingga mencapai kondisi kapasitas lapang dari awal tanam sampai dengan 90 HST dan digunakan sebagaiperlakuan non-stres. Sedangkan kelompok tanaman yang lain dipelihara dalam kondisi kapasitas lapanghingga 14 HST dan diberi perlakuan stres kekeringan dari umur 15 HST hingga panen (90 HST). Kandunganprolina diukur pada umur 63 HST (setelah 6x periode stres). Hasil penelitian menunjukkan semua tanamantembakau yang diuji mempunyai tinggi tanaman, diameter batang, jumlah, berat kering dan luas daun yanglebih rendah akibat perlakuan stres kekeringan yang diberikan dibandingkan dengan kondisi non-stres.Berdasarkan hasil perhitungan indeks sensitivitas terhadap stres kekeringan menggunakan peubah bobotdaun kering per tanaman maka tanaman TI zurlat dari tembakau GS transgenik P5CS generasi TO yang diujibersegregasi untuk kategori toleran, medium toleran dan peka, sedangkan tembakau GS non-transgenikdikategorikan sebagai medium toleran dan peka terhadap stres kekeringan. Tanaman TI zurlat dari tembakau GStransgenik P5CS generasi TO menunjukkan kandungan prolina yang lebih tinggi dalam kondisi stres kekeringandibandingkan dengan tembakau GS non-transgenik. Peningkatan akumulasi prolina yang cukup tinggi akibatover-ekspresi dari gen P5CS diduga berkorelasi dengan peningkatan toleransi tanaman terhadap stres kekeringan
Daya Gabung Galur-galur Jagung Berkualitas Protein Tinggi
Quality Protein Maize (QPM) is a special maize functioning as source of carbohydrate and protein, which contain protein components lysine and tryptophan higher than that of normal maize. Experiment was carried out to evaluate the combining abilities of inbred lines introgressed with opaque-2 mutant gene and their hybrid performances on grain yield and other agronomic characters. Genotype test consisted of eight lines, eight testers, sixty four hybrid crosses between lines x tester and four check varieties. The experiment was arranged in a randomized complete block design, with two replications, on the lowland in Walenreng (Bone) and on dry land in Bajeng (Gowa). Variance analyses were done following the line x tester model. Results showed that the effect of genotype x location interactions were significant for ear weight and yield characters. The grain yields of three lines showed positive and significant general combining ability those were Nei9008+o2-09 (L1), Nei9008+o2-14 (L3) and Nei9008 + o2-27 (L7), but for the tester was only MR10+o2-31 (T7). Another eight crosses were showing significant effect for specific combining ability, but only combination of Nei9008+o2-09 and o2+MR10-31 lines was significantly superior to all check hybrids
Identification of Wide Compatibility Varieties in Some Tropical Japonica Rice
The F1 hybrid sterility in indica/japonica crosses is the major barrier in developing hybrid rice varieties between these two diverse germplasm. The sterility problem in japonica/indica hybrids can be overcome by using wide compatibility genes. The objective of this study was to identify wide compatibility varieties (WCVs) in some tropical japonica rice. Twenty five tropical japonica varieties as male parents were crossed with indica (IR64) and japonica (Akitakomachi) testers as female parents. The crosses were planted following a randomized complete block design with three replications. Varieties having average spikelet fertility of more than 70% with both the indica and japonica testers were rated as WCVs. Result from this study showed that six tropical japonica varieties were classified as WCVs, i.e., Cabacu, Grogol, Kencana Bali, Klemas, Lampung Lawer, and Napa. Hybrid sterility is caused by partial sterility of male and female gametes. The WCVs from the present study can be used in hybrid rice breeding program to solve hybrid sterility in indica/japonica hybrids
Daya Hasil Dan Stabilitas Ratun Galur Padi Pada Lahan Pasang Surut
The study was aimed to determine the productivity and yield stability of ratoon rice genotypes in three environments and to obtain rice genotypes suistable for ratoonning on specific environment of tidal land. The experiment was designed in a randomized complete block with three replicates. Seedling was planted at 21 days old with spacing of 20 x 20 cm, one seedling per hill. Plants were harvested 30 days after heading by cutting at a height of 10 cm from the soil surface. One day after harvest, the land was irrigated as high as 3 cm and fertilized with Urea 50 kg/ha, TSP 30 kg/ha, and KCl 25 kg/ha. Yield stability was analyzed according to Eberhart and Russel (1966). Ratoons were sensitive to the environmental changes. Genotype IPB97-F-13-1-1, IPB 4S, and IPB 3S produced the main crop + ratoon grain yield of 5.26 t/ha, 5.14 t/ha, and 5.64 t/ha dry milling grain (DMG), respectively. Based on yield of the main crop + ratoon, IPB97-F-13-1-1 and IPB 4S was each considered as adaptable to the suboptimum condition (bi<1). Ratoon crop yield of genotype IPB97-F-13-1-1, IPB 4S, and IPB 3S each was the highest in three locations. The ratoon crop contribution to the rice production was from 31.3% to 61.9% to the main crop
Uji Cepat Toleransi Tanaman Padi terhadap Cekaman Rendaman pada Fase Vegetatif
The major constraint of rice cultivation in the flood-prone area is the lack of tolerant varieties. A rapid screening method have to be developed under controlled environments, such as a green house, to improve the effectiveness and efficiency of the selection under submergence condition. The aim of this research was to study the correlation beetween selection methods in greenhouse and in the field. This experiment was conducted at a green house of Muara Experimental Station, Bogor in 2011/2012. The experimental designs used were randomized complete design for greenhouse experiment and randomized complete block design for field experiment, with three replicates respectively. There were four sub-experiments in the greenhouse experiment, grouped based on seedling age (10 days and 35 days after seeding) and duration of submergence (10 days and 14 days). Those sub-experiments in the green house were compared with the experiment in the field. The results showed that there was strong correlation between recovery percentage in the green house and percentage recovery in the field. The same correlation indeed happen between recovery percentage in the green house to grain yield. Complete submergence at 10-day-old seedlings in green house could be developed as rapid selection method for submergence tolerant rice.Keywords: aciotic stress, correlation, flooding, Oryza sativ
Molecular Analysis and Effectiveness Assay of AV1 Gene in Transgenic Tobacco for Resistance to Begomovirus
Genetic transformationof tobacco plant using AV1 gene was conducted atthe previously experiment and generated transgenic tobaccoplants positively carrying the selectable marker nptII gene.The objectives of this experiment were to (1) analyze thepresence of Begomovirus AV1 gene in T0 generation putativetransgenic tobacco plants using PCR technique with specificprimers and its correlation with resistance phenotype, (2)analyze the integration and copy number of the transgene inT0 generation putative transgenic tobacco plants and itscorrelation with resistance response, (3) screen the T0generation putative transgenic tobacco plants with the targetvirus infection and to detect the presence of the virus in thetransgenic plant tissue using universal primers. PCRdetection of AV1 gene in tobacco transgenic was conductedby using specific primer for Begomovirus AV1 gene.Meanwhile, Southern Blot analysis was conducted by usingthe AV1 gene probe. The effectiveness of AV1 gene intobacco transgenic was tested by inoculation of target virususing whiteflies vector. Result of the experiments showedthat there was a positive correlation between the presenceof the AV1 transgene in T0 generation putative transgenictobacco plants and the resistant phenotype. Transgenicplants with a single copy integration of the transgeneexhibited more resistant than the multiple copy one. andnon transgenic plant. The resistance as a result of AV1 geneexpression was indicated with no symptom in T0 generationtransgenic tobacco plants and the accumulation of the virusin the transgenic plants tissue. Northern and Westernhybridization analysis need to be perfomed for investigatingthe presence of mRNA or protein accumulation so that theresistance mechanism of the AV1 gene could be explainedmore detail
SCAR (Sequence Characterized Amplified Region) Analysis for Pi-b and Pi-ta Genes on 28 Genotypes of Rice
Evaluation to blast disease (Pyricularia grisea) resistance was carried out by using two SCAR (Sequence Characterized Amplified Region) markers of Pi-b and Pi-ta blast resistance genes, and spray-inoculation method with 10 races of P. grisea on 28 paddy genotypes, that consisted six wild genotypes of rice. The results revealed that among 28 paddy genotypes, fifteen genotypes carrying both genes including Oryza rufipogon; six genotypes carrying Pi-b genes including O. alta, two genotypes carrying Pi-ta gene, and five genotypes did not possess both gene including O. glumaepatula, O. officinalis, O. latifolia, and O. malapuzhaensis. Based on infection intensity, the evaluated genotypes were vary in responses to different ten races of P. grisea, indicated that the evaluated genotypes were vary in carrying Pi genes. Analysis in detail indicated that existence of Pi-ta gene associated with lower infection intensity caused by P. grisea race 063 C
- …