Posterb presentations Đề tài nghiên cứu về cây lúa

IRC14-0370 01a Ex situ conservation and dissemination of rice germplasm SHOULD THE GENEBANK STANDARDS FOR SEED DRYING PRIOR TO LONGTERM STORAGE BE CHANGED? K Whitehouse1, F Hay2, R Ellis1 Agriculture Policy and Development, University of Reading, Reading, United Kingdom Genetic Resources Center, International Rice Research Institute, Los Banos, Philippines Purpose: Despite remaining several decades under genebank storage conditions, over time seed viability declines and regeneration is required to maintain genetic integrity While recommendations for the management of genebank accessions emphasise the importance of seed drying to extend subsequent seed longevity during storage, there has not been a critical evaluation (impact on subsequent quality / longevity of the seeds) of the conditions that are actually used by genebanks for any species Approach and methods used: Seed storage experiments were used to evaluate the relative longevity of seeds of 20 diverse rice accessions (representing five variety groups), following initial drying in a dry room (DR) running within recommended genebank conditions (15% RH, 15°C), or using heated air (45°C) in a flat-bed batch dryer (BD) Seed longevity under real-time genebank storage was estimated by extrapolation from the results of the seed storage experiments Key results: The initial rate of drying did not appear to differ between the different drying methods, however initial drying in the BD resulted in significantly greater subsequent longevity compared with initial drying in the DR for 14 accessions, with the difference in longevity (as measured by the time for viability to fall to 50%; p50) as a percentage of the p50 of seeds initially dried in the DR Initial drying for a single daily cycle (8 hours) in the BD compared with drying in the DR never had a negative effect on subsequent longevity There were significant (P < 0.01) linear relationships between the percentage difference in p50 (BR/DR) and each of harvest date, harvest moisture content and the p50 of DR seeds, but not with maturity (days after anthesis) of the seeds at harvest Synthesis and Applications: IRRI currently regenerates over 4000 accessions annually; this figure could potentially be reduced due to the greater longevity of rice accessions if IRRI were to routinely use the BD for drying accessions regenerated at IRRI Beyond IRRI, if similar results are obtained from, in particular, other cereal species, it may be necessary to change the current genebank standards for drying to ensure seeds have maximum longevity when they are first placed into storage IRC14-0445 01a Ex situ conservation and dissemination of rice germplasm PHYSIOLOGICAL AND GENETIC CHANGES IN RICE (ORYZA SPP) SEEDS DURING AGEING K.A Adeboye1, I.O Daniel1, J.G Bodunde2, M.A Ayo-Vaughan1, J.A Adetumbi3, E.O Idehen1, O.W Adabale1 Plant Breeding and Seed Technology, Federal University of Agriculture Abeokuta, Abeokuta, Nigeria horticulture, Federal University of Agriculture Abeokuta, Abeokuta, Nigeria grain legumes improvement programme, Institute of Agricultural Research & Training PMB 5029 Moor Plantation, ibadan, Nigeria Purpose: Seed deterioration in terms of viability and vigour has implications on erosion of variability in genetic resources especially in gene bank seed collections This study was conducted to evaluate physiological and genetic integrity of rice seeds during storage in a controlled deterioration experiment Approach and methods used: Ten accessions of rice sourced from the gene bank of National Centre for Genetic Resources and Biotechnology (NACGRAB) Ibadan, Nigeria, were subjected to artificial ageing The procedure involved storing the seeds at 45°C and 75% Relative Humidity in a chamber Samples of three replicates of 20 seeds each were randomly drawn from the chamber at 0, 3, 24, 48, 55 and 72 hours These samples were subjected to standard germination tests and DNA analysis Data were collected on seed germination count, percentage germination and seedling length Seed germination rate and vigour index were estimated Genetic changes during ageing were evaluated by Simple Sequence Repeat (SSR) analysis using DNA primers in a Direct PCR kit All experiments were Completely Randomised and percentage germination data were subjected to arc sine transformation and Analysis of Variance Seed longevity data were subjected to Probit analysis and genetic profiles were analysed by estimating probability of genetic drift using Nei’s formula Genetic distances were estimated using PASTTM software and percentage genetic integrity was estimated from the genetic distance matrices Key results: A progressive decline was observed in the viability and seedling vigour index and were maximal at 72 hours of ageing with seed viability value for all accessions averaging 54.25% Probit analysis revealed that NERICA had the best storage potential (P50 = 82 hours) compared with other accessions Variation observed in the genetic integrity was revealed by primer RM 178, which showed significant probability (p < 0.05) of genetic drift for all the accessions Percentage genetic integrity calculated ranged from 99.45 in NERICA to 100 in IR 64 and deterioration was maximal at 72 hours of ageing when percentage seed germination was 54.25 Synthesis and Applications: In order to maintain optimal genetic integrity during storage, a seed viability benchmark of 54% is recommended for regeneration of stored rice seeds IRC14-0552 01a Ex situ conservation and dissemination of rice germplasm ASSESSMENT OF VIABILITY, GERMINATION POTENTIAL AND DORMANCY BREAKING METHODS OF SRI LANKAN ENDEMIC WILD RICE SPECIES ORYZA RHIZOMATIS G Rajkumar1, J Weerasena2, K Fernando3, Y Liyanage4 Department of Botany, University of Jaffna, Jaffna, Sri Lanka Institute of Biochemistry Molecular Biology and Biotechnology, University of Colombo, Colombo, Sri Lanka Agricultural Biotechnological Centre, University of Peredeniya, Kandy, Sri Lanka Seed Testing Laboratory, Deaprtment of Agriculture, Kandy, Sri Lanka Purpose: Oryza rhizomatis is an endemic wild rice species of Sri Lanka Seeds of O rhizomatis may have a special structure and dormancy to tide over unfavorable conditions of dry zones of Sri Lanka Studies carried out to findout prediction of viability, germination and dormancy breaking methods for the seeds of O.rhizomatis Commercial cultivated variety Bg352 was used as a control Approach and methods used: The experiments were carried out on pure seeds Four hundred seeds from each seed lot were used for viability, dormancy breaking and germination test with eight replicates of 50 seeds and these were subjected to various treatments separately The seeds were soaked in distilled water for 3-18 hours before staining and a cut was made through the middle of the embryonic axis of the seeds The seeds were immersed in 1% TZ solution These were incubated in darkness for 2-36 hours for the viability test Viability of each seed was interpreted according to the topographical staining pattern of the embryo and the intensity of the colouration Heat, mechanical and chemical treatments were done to break the dormancy of seeds The germination of O rhizomatis was tested using germination boxes containing sterile soil First and the final counts were taken after 5th and 14th days respectively by visual observation Germination and the mortality rates were calculated Key results: O rhizomatis seeds used in the study were found to be 80% viable However, only 5% of seeds germinated under the optimum laboratory conditions From this study, it was confirmed that O rhizomatis seeds are dormancy thus proper treatments are required to break the dormancy as compared to Bg352 Experiments carried out to break dormancy showed that seeds subjected to heat treatment at 50oC for 96 hours followed by removing husks and soaking them in 0.1 M HNO3 for 24 hours increased the germination up to 76% Synthesis and Applications: Therefore, these studies provide rapid, effective and valuable techniques for prediction of seed viability, breaking of dormancy and for optimum germination of the seeds of O rhizomatis The present studies will pave the way for successful cultivation and multiplication of this species, which is crucial for varietal development IRC14-1056 01a Ex situ conservation and dissemination of rice germplasm GENETIC DIVERSITY OF IRANIAN RICE GERMPLASM THROUGH AGRO-MORPHOLOGICAL TRAITS M Jahani1, M.H Fotokian2, B Nakhoda3, G Mohammadi-Nejad4 agronomy and plant breeding, Shahid Bahonar University of Kerman, Kerman, Iran agronomy and plant breeding, Shahed University, Tehran, Iran Department of molecular physiology, Agricultural Biotechnology Research Institute of Iran, Karaj, Iran Plant Breeding, Shahid Bahonar University of Kerman, Kerman, Iran Purpose: Genetic diversity constitutes the raw material for plant improvement, and provides protection against genetic vulnerability to biotic and abiotic stresses Iran has diverse agronomic landscape and potentially preserves high level of genetic resources for rice genotypes The major objective of this study was to quantify genetic diversity of Iranian rice genotypes Approach and methods used: Morphological characterization of 36 rice genotypes using 17 agro-morphological traits was done in a field experiment by a lattice design with replication Analysis of variance, Cluster analysis and principal component analysis were carried out Key results: Analysis of variance showed that the differences among genotypes for all the characters under study were highly significant, indicating that the genotypes were highly diversified PCA components explained 87.86% of variation.The clustering pattern clearly grouped the genotypes based on their originality, breeding variety, genotypes, landraces and conventional variety generally were clustered into the different groups or subgroups Synthesis and Applications: The importance of the conservation in on-farm landraces of Oryza Sativa and its wild relatives was proposed in order to ensure the genetic resources for further breeding and conserve biological diversity IRC14-1122 01a Ex situ conservation and dissemination of rice germplasm CAN CHLOROPHYLL FLUORESCENCE BE USED TO DETERMINE THE OPTIMAL TIME TO HARVEST RICE SEEDS FOR LONG-TERM GENEBANK STORAGE? S Timple1, F.R Hay1, B van Duijn2 T.T Chang Genetic Resources Center, International Rice Research Institute, Los Baños, Philippines Leiden University, Institute Biology Leiden and Fytagoras, Sylviusweg 72 2333 BE Leiden, Netherlands Purpose: The study aims to examine the potential use of chlorophyll fluorescence (CF) to determine the optimal time to harvest rice seeds for maximum longevity in genebank storage Approach and methods used: Twenty rice accessions from the International Rice Genebank (IRG) at IRRI were planted during the 2013 dry season and harvested at 24, 31, 38 and 45 days after peak flowering After threshing and drying, half of each seed lot was hand-sorted by genebank staff Comparative longevity experiments were conducted with and without hand-sorting at 10.9% moisture content and 45°C Samples were taken every days for up to 60 days for viability monitoring through a standard germination test and the time for viability to fall to 50% (p50), as a measure of seed longevity, determined Hand-sorted and non-sorted samples of the seed lots were subjected to CF analysis using the SeedAnalyser Key results: Seed longevity generally increased during seed development, with p50 increasing by between 42.8 and 348.6% between the first and last harvest CF curves (number vs pico-amps) showed distinct peaks but were significantly skewed The position of the peak and area under the curves (total CF) varied with accession, maturity and whether or not the seeds had been manually sorted Total CF was generally highest in the least mature seeds and decreased with increasing maturity (by between 0.25 and 6.30%, depending on accession) The position of the peak shifted downwards by between 60 and 1050 pA as maturity increased between 24 and 45 DAF Synthesis and Applications: Harvesting seeds at optimum maturity is extremely important to obtain seeds of high quality with maximum potential longevity It is therefore essential to have an effective and reliable technique to be able to determine optimal harvesting time of rice seeds for conservation in long-term storage Based on the CF and comparative longevity results, the potential use of CF to improve genebank operations will be discussed IRC14-1291 01a Ex situ conservation and dissemination of rice germplasm USE OF FUNGICIDES AND RELATIONS WITH THE QUALITY AND CONSERVATION OF RICE SEEDS I.S.N Dario1, A.D.L.C Novembre1 Crop Science, Universidade de São Paulo, Piracicaba, Brazil Purpose: Brasil is the 9th largest producer of rice and the first outside Asia, with production of 12.3 million tons in 2013/14 harvest and productivity of 7.0 ton/ha in irrigated areas The incidence of disease is a major factor affecting rice production in Brazil and the seed treatment with fungicides is a recent study This research has the purpose to evaluate the interference of fungicide application on the quality of rice seeds, according to the enviroment and period of storage Approach and methods used: The experiment was developed at the Laboratory of Seeds Analysis, Crop Science Department, Universidade de São Paulo, Piracicaba, Brasil The research consisted of 72 treatments and repetitions: nine seed lots of three important cultivars of rice produced in Brazil, treated with the fungicides Penflufem + Trifloxystrobin, Thiabendazole + Metalaxyl + Fludioxonil and Pyraclostrobin + Thiophanate-methyl + Fipronil, at doses of 50, 100 and 150 ml / 100 kg seed of rice, respectively, having a control without treatment, these seeds were stored for 120 days in two environments: natural and dry cold room (10 °C and 20% RH) The seeds were evaluated 1, 15, 30, 60 and 120 days after treatment To determine the seed quality were evaluated water content, germination, vigor (first count of germination, seedling length, accelerated aging and cold tests) and sanity The experimental design was completely randomised, with analysis of variance for each cultivar and comparison of average by Tukey test (5%) Key results: The results indicate: a) There is the influence of the fungicide, the environment and the storage period on rice seeds quality; b) The fungicide interference on the rice seeds quality varies according to the cultivar; c) Fungicides are efficient for the control of major pathogenic fungus associated with rice seeds Synthesis and Applications: It is vital that the rice seeds are stored in period and environment appropriate to maintain their quality for a longer period of time, and are treated with fungicides to ensure their sanity, preventing the spread of disease in producing areas IRC14-1361 01a Ex situ conservation and dissemination of rice germplasm THE INTERNATIONAL RICE GENEBANK: RECENT DEVELOPMENTS IN MANAGING THE WORLD RICE COLLECTION F De Guzman1, R Reano1, M.S Almazan1, G.L Capilit1, N.R Sackville Hamilton1 TTC Genetic Resources Center, International Rice Research Institute, Los Baños, Philippines Purpose: The International Rice Genebank (IRG) at IRRI, having more than 121,000 available accessions, holds the largest and the most diverse collection of rice genetic resources The search, development and implementation of best conservation strategies have been the utmost priority of IRG to maximize the storage life, maintain genetic integrity, and ensure availability of high quality seeds and information of the collection Approach and methods used: IRG, through the support of the Global Crop Diversity Trust (GCDT) is continuously renovating its facilities and improving protocols The Seed Physiology section with modern equipment was established to conduct research to optimize procedures and practices focusing on seed development, drying, storage and dormancy New applications and modifications were added to the Genetic Resources Information Management System (GRIMS) to cope with the improvement in protocols It was linked to the International Rice Information System (IRIS) for better documentation, genealogy and germplasm tracking The genebank has implemented the use of barcoding and Android technology not only for precise inventory of stocks and accurate seed dissemination but also for efficient paperless data collection for plant monitoring and characterization activities Biosystematic studies are being done to verify relationship between and among species, and molecular research activities are conducted to enhance germplasm utilization Key results: The improvements in facilities and procedures, and shift to automated data collection resulted to a more efficient and cost effective conservation, regeneration, characterization and distribution strategies to handle the increasing collections (e.g GCDT regeneration and Gatsby collection projects, genetic stocks) and requests The collection is now more secured with approximately 98% backed up at National Center for Genetic Resources Preservation (NCGRP) and Svalbard Global Seed Vault (SGSV) Synthesis and Applications: The recent genebank developments have greatly helped in managing the huge collection and facilitated the seed distribution process These various activities and strategies undertaken by IRG have mitigated identified risks in the conservation of rice genetic resources as well as assured the general public and germplasm owners of the availability of quality seeds and information IRC14-0057 01b In situ conservation of wild rices ASSESSMENT OF MORPHOLOGICAL DIVERSITY WITHIN WILD RICE (ORYZA RUFIPOGON GRIFF.) GERMPLASM OF NBU CAMPUS (WEST BENGAL) FOR IN SITU CONSERVATION- A CASE STUDY S Roy1 Department of Botany, University of North Bengal, Siliguri, India Purpose: Population of Oryza rufipogon Griff (Poaceae) have been gradually reduced due to ecological stresses It has proven to be a valuable reservoir of genes for rice genetic improvement as a progenitor of cultivated rice (O sativa L.) It needs immediate attention with high priority so that we could not loss this agriculturally important Oryza gene pool Approach and methods used: Natural population of Oryza rufipogon in the North Bengal University campus is characterized based on phylogeographic and morphological parameters for conservation purposes Twenty-five plants were considered randomly to measures twenty-six different types of morphological passport data for genetic relatedness analysis within the population Diagnostic characters are provided to delineate the species morphologically Key results: Plant is annual ecotype having culms height 64 cm -145 cm Profuse fibrous roots of mm thick and – cm long creamy-white in colour grows from the floating nodes, node region is solid and pinkish in colour (5-7 mm long) Flag leaf length ranges from 13 cm – 40 cm with 0.3 cm – 1.8 cm width Flag leaf blade attitude is varying from deflexed to horizontal to semierect Auricle was hard, curved and 13 – 15.5 mm in size Two-cleft ligule length ranges 17 mm to 35 mm Panicle length varies from 15.4 cm – 30 cm with cm – cm wide with 5-13 primary branches Attitude of primary branches is spreading, well-exserted (100%), alternately arranged on the wavy axis Length of the lemma varies 6-11 mm and 1.4 – 2.3 mm wide, lemma-awn junction marked by a pinkish pubescent constriction with 23 – 80 mm long red awn Yellow colour anthers vary in length 4-8 mm long Stigma was bifurcated (> mm) and purple in colour comes out from the spikelets Seeds (blackish) are harvested during November-December and vary in length (7.5 mm – 10 mm) Density of fertile spikelets ranges from 15 to 82 Grain length/breadth ratio was 3.73 (average) and average kernel length/breadth ratio was 3.99 Synthesis and Applications: The results suggest that the population of NBU campus are genetically diversified, heterogeneous and should be conserved in situ to protect this precious genetic resource as separate ecological race (ecotype or intergrade) for germplasm enhancement IRC14-0080 01c Conservation and use of traditional varieties (incl on farm conservation) CONSERVATION OF AROMATIC RICE BIODIVERSITY: HERITAGE OF BANGLADESH M Salam1, M Islam1, P Saha1 Agriculture and Food Security, BRAC, Gazipur, Bangladesh Purpose: Small grain aromatic rice landraces are the thousand year’s tradition of Bangladesh Because of many aristocratic dishes viz Polao, Berani, Firny and Payesh are prepared from this group of rice varieties Serving those prestigious foods to dignitaries, guests and ceremonial functions is a Bangladeshi culture But the cultivation of these varieties has been progressively diminishing due to their low yields and photoperiod sensitivity that restrict their production to the wet season Recently, several media reports reflected concerns of the risk of extinction of this precious heritage Therefore, efforts have been taken to collect and conserve these cultivars to maintain rice biodiversity Approach and methods used: Nationwide field collection was done by village level staff of BRAC Accessions were assembled from BRRI gene bank and Bangabandhu Sheikh Mujibur Rahaman Agricultural University and 154 genotypes were grown at BRAC farm, Gazipur, during Aman season of 2013 Twenty five days old seedlings were transplanted at spacing of 15x20 cm in 5.1m2 plot, with one seedling per hill Date of flowering, plant height, maturity, grain color, shape, size, pericarp color and aroma were compared for purification and removal of duplications Breeding programs were initiated for the improvement of these national grade aromatic varieties and pure lines (PL) are being evaluated in multilocation trials Key results: The varieties showed a wide variation in dates of flowering, plant height and grain shape, size, color and aroma We isolated and purified 104 accessions and preserved the seeds PLs were distinct, for example, Kalijira-PL1 and Kalijira-PL9 were one week earlier and had 0.5 t ha-1 yield advantage over the original Kalijira check, and their grain morphology is distinguishable from each other and the original variety Breeding populations were developed by involving these aromatic landraces and small grain HYVs Synthesis and Applications: DNA fingerprinting of these varieties is in progress for IPR issue The pure stocks of seeds are now ready for sharing with rice scientists and relevant organizations for further improvement BRAC will continue to save this heritage through on-farm conservation and proper storage IRC14-1296 01d Taxonomy of rice TOWARDS A STABLE ORYZA TAXONOMY: BIOSYSTEMATICS RESEARCH IN THE INTERNATIONAL RICE GENEBANK M.C.N Banaticla-Hilario1, M.E.B Naredo1, M.S.R Almazan1, S.M.Q Mercado1, G.L.S Capilit1, K.L McNally1, N.R Sackville Hamilton1 T.T Chang Genetic Resources Center, International Rice Research Institute, Los Baños, Philippines Purpose: Taxonomic information is vital in documenting and managing plant genetic resources Accurate classification and identification of genebank accessions provide a solid foundation for characterization, evaluation, and utilization of the conserved germplasm The International Rice Genebank (IRG) aims to authenticate the taxonomic identity of all the (~4700) wild Oryza accessions under its custody Depending on the classification scheme, however, nomenclatural problems exist in the genus Oryza mainly attributed to (1) presence of diploid and tetraploid forms in a taxon (2) presence of continuous morphological variation between two taxa Approach and methods used: At the IRG, studies are being conducted to verify relationships between and among taxa based on various biosystematic evidences such as phenotype-, genotype- and crossability data Species or species complex in focus for the problems identified include: 1) the African CC genome species, O punctata; 2) the Asian AA genome species O nivara and O rufipogon; and 3) species of the O meyeriana complex, O granulata and O meyeriana Key results: Morphological data on Series Latifoliae species separated the tetraploids from the diploid forms of O punctata This supports the recognition of the tetraploid forms as a distinct species O schweinfurthiana An ecogeographic analysis of O nivara and O rufipogon accessions suggested the treatment of these taxa as separate species based on the following arguments: a) ecological distinction; b) substantial pre-zygotic isolation; 3) differences in gene flow– and genetic variation patterns; 4) local scale genetic divergence and 5) reinforced gene flow barriers under sympatric conditions Preliminary analyses based on morphological and molecular data support the treatment of O granulata and O meyeriana as distinct species Synthesis and Applications: Through these biosystematic studies, IRG hopes to resolve species relationships and contribute to a more stable taxonomy for the genus Oryza The research results can enable the gene bank community to correctly classify and manage their wild rice collections IRC14-1362 07d Production systems and crop management/protection POTASSIUM PHOSPHITE AND FUNGICIDE IN THE CONTROL OF STEM ROT AND SHEATH SPOT OF RICE S Martínez1, F Escalante1, L.A Casales1, A Vergara1 Plant Pathology, INIA Treinta y Tres, Treinta y Tres, Uruguay Purpose: Stem rot (Sclerotium oryzae) and sheath spot (Rhizoctonia spp.) are serious diseases of rice crop in Uruguay Disease management is complicated in intensive cropping systems and fungicide application is the most common management practice Phosphites are salts of phosphorous acid used in agriculture in control of plant diseases caused by Oomycetes and Fungi However, little information is available about the use of phosphites in plant disease control in the rice crop The present work is a preliminary study on the effects of K phosphite (Kph) in the control of stem and sheath diseases of rice Approach and methods used: Field experiments were conducted in 2012/13 and 2013/14 at UEPL-INIA Treinta y Tres field experimental station on rice plots (cv El Paso 144) Seven treatments consisting of early flowering applications of Kph (71% w/v) in simple (2.5 L/ha) and double doses (2Kph), fungicide (F, Azoxystrobin 250 g/L + Ciproconazole 100 g/L, 300 cc/ha), fungicide plus simple (FKph) and double doses of Kph (F2Kph), half doze of fungicide with simple doze of Kph (½FKph) and an untreated control Stem rot and sheath spot incidence and severity (severity index level, IGS) at flowering and harvest and yield and yield components were evaluated Key results: The IGS of stem rot was significantly (p