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Rapid identification of transgenic cotton (Gossypium hirsutum L.) plants by loop-mediated isothermal amplificationOriginal PaperNiloofar Rostamkhani, Ali Haghnazari, Masoud Tohidfar, Aboubakr MoradiCzech J. Genet. Plant Breed., 2011, 47(4):140-148 | DOI: 10.17221/7/2011-CJGPB In an attempt to speed up the process of screening of transgenic cotton (G. hirsutum L.) plants, a visual and rapid loop-mediated isothermal amplification (LAMP) assay was adopted. Genomic DNA was extracted from fresh leaf tissues of T2 transgenic cotton containing chitinase (chi) and cry1A(b) genes. Detection of genes of interest was performed by polymerase chain reaction (PCR), LAMP and real-time PCR methods. In LAMP assay the amplification was performed after 30 min at 65°C when loop primers were involved in the reaction. The involvement of loop primers decreased the time needed for amplification. By testing serial tenfold dilutions (10-1 to 10-8) of the genes of interest, the detection sensitivity of LAMP was found to be 100-fold higher than that of PCR. The rapid DNA extraction method and LAMP assay can be performed within 30 min and the derived LAMP products can be directly observed as visually detectable based on turbidity in the reaction tube. The accuracy of LAMP method in the screening of transgenes was confirmed by PCR and real-time PCR. The developed method was efficient, rapid and sensitive in the screening of cotton transgenic plants. This method can be applied to any other crops. |
AFLP and SSR markers linked to the yellow seed colour gene in Brassica juncea L.Original PaperZhen HUANG, Yu ZHANG, Hui Qiang LI, Li YANG, Yuan Yuan BAN, Ai Xia XU, En Shi XIAOCzech J. Genet. Plant Breed., 2011, 47(4):149-155 | DOI: 10.17221/109/2011-CJGPB Yellow mustard, cultivated in northern Shaanxi of China, is a valuable germplasm of Brassica juncea with low erucic acid content. Its yellow seed colour is controlled by a recessive allele of a single gene, whose dominant allele conditions brown seed colour. To map the yellow seed colour allele, amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) technologies were used to identify markers linked to the recessive allele. The analysis was done on 386 F2 plants, segregating for seed colour, from the cross Wuqi yellow mustard × Wugong mustard. The plants were selfed to determine their seed colour genotype. Twenty AFLP markers and eight SSR markers were identified from 256 AFLP primer combinations and 624 pairs of SSR primers, respectively. Blast analysis indicated that the sequences of four closely linked AFLP and SSR markers showed good collinearity with those of Arabidopsis chromosome 3, and the homologue of the yellow seed colour allele was located between At3g14190 and At3g32130. Sequence information of the region between the two genes of Arabidopsis could be used to develop more closely linked markers to narrow down the homologue of the yellow seed colour allele. These results would accelerate the procedure of yellow seed colour gene cloning and marker-assisted selection for yellow mustard. |
Wheat germplasm screening for stem rust resistance using conventional and molecular techniquesA. KOKHMETOVA, A. MORGOUNOV, S. RSALIEV, A. RSALIEV, G. YESSENBEKOVA, L. TYPINACzech J. Genet. Plant Breed., 2011, 47(10):S146-S154 | DOI: 10.17221/3270-CJGPB In Central Asia, stem rust (Puccinia graminis f.sp. tritici) causes considerable damage, especially during growing seasons with high rainfall. Ug99 is a race of stem rust that is virulent to the majority of wheat varieties. To develop disease-free germplasm, wheat material was screened using the predominant stem rust races of Kazakhstan and tested in two nurseries; CIMMYT-Turkey and the Plant Breeding Station at Njoro, Kenya. A total of 11 pathotypes of P. graminis f.sp. tritici were identified in Kazakhstan from the stem rust samples collected in 2008-2009. In particular, pathotypes TDT/H, TPS/H, TTH/K, TKH/R, TKT/C and TFK/R were highly virulent. Of the 170 advanced lines of wheat, 21 CIMMYT lines resistant to 5 aggressive Kazakhstani pathotypes of P. graminis were identified. A high level of resistance was observed in 11 wheat cultivars and advanced lines: Taza, E-19, E-99, E-102, E-572, E-796, E-809 (Kazakhstan), Ekinchi (Azerbaijan), Dostlik, Ulugbek 600 (Uzbekistan) and Umanka (Russia). Based on data obtained from Turkey-CIMMYT and the Plant Breeding Station Njoro, Kenya nurseries, out of 13 tested entries, 6 wheat breeding lines which were resistant to both stem and yellow rust and 10 wheat lines which showed high and moderate levels of resistance to Ug99 were selected. Using the sequence tagged site (STS) molecular marker Sr24#12, associated with Sr24/Lr24, seven wheat entries resistant to stem rust were identified. These results will assist breeders in choosing parents for crossing in programmes aimed at developing varieties with desirable levels of stem rust resistance in Kazakhstan and they will also facilitate stacking the resistance genes into advanced breeding lines. |
Breeding adult plant resistance to stripe rust in spring bread wheat germplasm adapted to Sichuan Province of ChinaE.N. YANG, Y. C. ZOU, W. Y. YANG, Y. L. TANG, Z.H. HE, R.P. SINGHCzech J. Genet. Plant Breed., 2011, 47(10):S165-S168 | DOI: 10.17221/3273-CJGPB Sichuan is an important wheat producing province of China where severe stripe rust epidemics occur annually. Developing high-yielding wheat varieties with good and stable stripe rust resistance is a foremost breeding objective of all breeding programs. Because minor gene based adult-plant resistance (APR) is considered durable, a shuttle breeding program between Sichuan Academy of Agricultural Sciences (SAAS) and CIMMYT was initiated in 2000 to transfer APR identified in CIMMYT wheats to wheat germplasm adapted in Sichuan. During 2007-2009, a total of 669 advanced generation lines obtained from this shuttle breeding effort were provided to the Plant Protection Research Institute, SAAS for official multi-environment stripe rust tests, and 231 elite lines were characterized for yield performance by the agronomists at the Crop Research Institute, SAAS. Between 11-39% lines were highly resistant depending on the year of testing and 17 (7.3%) lines had 5% or higher yields than the check mean. The adapted resistant lines are being used by various breeding programs to enhance resistance diversity, and three lines are being tested in National or Provincial Yield Trials for possible releases. |
N.I. Vavilov's theory of centres of diversity in the light of current understanding of wheat diversity, domestication and evolutionJ. DVORAK, M.-C. LUO, E.D. AKHUNOVCzech J. Genet. Plant Breed., 2011, 47(10):S20-S27 | DOI: 10.17221/3249-CJGPB N.I. Vavilov hypothesized that the geographical centres of diversity of crops indicate their geographical centres of origin. Vavilov's conclusions about the geographical origins of einkorn, durum and common wheat agree well with current population and molecular genetic studies when macro-geography is used but agree poorly when they are examined at higher resolution. We examined the causes of such disagreements for tetraploid emmer wheat and hexaploid common and club wheat. Molecular studies suggest that emmer was domesticated in the Diyarbakir region in south-eastern Turkey. Nucleotide diversity of wild emmer in the Diyarbakir region estimated earlier was compared with nucleotide diversity of wild and domesticated emmer across their distribution estimated here. Although domesticated emmer is only half as diverse as wild emmer, it is more diverse than the ancestral wild emmer population in the Diyarbakir region. Its centre of diversity is in the Mediterranean and does not coincide with the geographical centre of emmer origin. A similar disagreement exists in hexaploid wheat. Its centre of molecular diversity is in Turkey, which is west of the putative site of its origin in Transcaucasia and north-western Iran. It is shown that the primary cause of the disagreements between geographical centres of crop diversity and geographical centres of crop origin is gene flow from an ancestor subsequently to crop origin, which modifies the geographical pattern of crop diversity. When such gene flow takes place and when crop is domesticated in a peripheral population of the ancestor, the centre of crop diversity and the centre of crop origin are unlikely to coincide. |
Transferring useful rye genes to wheat, using triticale as a bridgeN.N. SAULESCU, G. ITTU, M. CIUCA, M. ITTU, G. SERBAN, P. MUSTATEACzech J. Genet. Plant Breed., 2011, 47(10):S56-S62 | DOI: 10.17221/3255-CJGPB Rye has already proven to be a good donor of genes for improving important traits and diversity in wheat breeding. The agronomic advantages of wheat-rye translocations, as well as their detrimental pleiotropic effects,were shown to be dependent on the source of the transferred rye chromatin. This justifies continued effort for introgression of rye genes from various sources into various wheat backgrounds. There are still many genes of interest for wheat improvement, not yet transferred, that are available in the rye genome. This paper describes the strategy applied at the National Agricultural Research and Development Institute Fundulea (Romania), to take advantage of the existence of intensive breeding programs in both winter wheat and triticale, and presents some of the results obtained so far by applying this strategy, in obtaining lines with common bunt, barley yellow dwarf (BYDV) and other diseases resistances, as well as improved seedling vigour and crop spectral reflectance. |
Tracking of powdery mildew and leaf rust resistance genes in Triticum boeoticum and T. urartu, wild relatives of common wheatOriginal PaperNelli A. Hovhannisyan, Mohammad Ehsan Dulloo, Aleksandr H. Yesayan, Helmut Knüpffer, Ahmed AmriCzech J. Genet. Plant Breed., 2011, 47(2):45-57 | DOI: 10.17221/127/2010-CJGPB Wild Triticum and Aegilops species are increasingly used in wheat breeding programmes around the world as donors of genes conferring resistance to biotic and abiotic stresses, as well as of genes that contribute to the improvement of grain quality. In the present study, thirty-nine accessions of diploid species with the A genome (Triticum boeoticum and T. urartu) were evaluated for the presence of the genes conferring resistance to powdery mildew (Blumeria graminis) and leaf rust (Puccinia recondita) using both inoculation tests and sequence tagged sites (STS) marker analyses in order to find correspondence between STS markers and resistance as a trait. The most resistant entries were T. boeoticum accessions. All the marked Lr and Pm resistance genes (Pm1, Pm2, Pm3, Lr10, Lr47, Lr25 and Lr28) were identified in the check T. aestivum cultivar Bezostaya 1. The resistance to powdery mildew in the material studied was conferred by the combination of the Pm1 gene with either Pm2 or Pm3. The Pm1 and Pm3 markers appeared to be suitable for tracking these powdery mildew resistance genes, while the Pm2 gene marker cannot be considered as usable in various genetically different wheat accessions. The presence of the genes Lr25, Lr28 and Lr47 seems to be particularly useful for obtaining leaf rust resistance in T. boeoticum and T. urartu species. |
Pseudo-embryogenic structures in anther and isolated microspore cultures in vitro: a cautionary guideReviewUgur BAL, Mehran E. SHARIATPANAHI, Antonio J. CASTRO, Delphine EMERY, Christophe CLÉMENT, Maryam DEHESTANI-ARDAKANI, Khadijeh MOZAFFARI, Alisher TOURAEVCzech J. Genet. Plant Breed., 2012, 48(2):51-60 | DOI: 10.17221/176/2011-CJGPB This review describes sources of structures of non-microspore origin observed in anther and microspore cultures. Various characteristics of these structures may cause a wrong diagnosis of these structures as embryos or cell/tissue clusters of microspore origin. Here we suggest such structures to be named as pseudo-embryogenic structures. The introduction of pseudo-embryogenic structures and their origins could be helpful to distinguish them from true microspore-derived structures. Prompted by certain environmental cues, somatic cells existing as a contamination in immature pollen (microspores) cultures can lead to the formation of 'pseudo-embryos' commonly known as embryoids. The pseudo-embryogenic structures may be classified in the following groups: (i) pseudo-star-like structures; pseudo-multicellular structures; (ii) pseudo-embryos with pseudo-suspensors; (iii) contaminating bacteria appearing as callus colonies; (iv) calli and embryos of somatic origin; (v) giant tetrad-like structures; (vi) anther wall cells. The exact origin of these structures is discussed in this paper, and some recommendations are proposed in order to avoid misinterpretation. |
Molecular analysis of temporal genetic structuring in pea (Pisum sativum L.) cultivars bred in the Czech Republic and in former Czechoslovakia since the mid-20th centuryOriginal PaperJaroslava CIESLAROVÁ, Miroslav HÝBL, Miroslav GRIGA, Petr SMÝKALCzech J. Genet. Plant Breed., 2012, 48(2):61-73 | DOI: 10.17221/127/2011-CJGPB Changes in genetic diversity of peas bred in the Czech Republic and in former Czechoslovakia since the mid-20th century were analysed using 38 molecular marker loci, including retrotransposons and microsatellites, differentiating a total of 84 alleles. Both marker types were comparably effective in revealing the genetic diversity, with a high correlation (r = 0.81), although the pairwise genetic distances of each marker type differed. In total, 175 accessions, selected from the Czech pea gene bank collection and representing the pea cultivars collected or bred in the country, were divided into three groups according to their date of sampling or variety registration. The first group contained 70 old cultivars and landraces collected prior to 1961. The second group contained 46 cultivars released from 1961 to 1980. The third group contained 59 cultivars released between 1981 and 2004. In spite of the decline in several diversity measures, differences in allele frequencies and even allele loss in three microsatellite loci were recorded over the 70-year period, while these differences between the groups were not statistically significant. In addition, genetic heterogeneity was detected in 29 accessions (15%). This indicates that although no genetic erosion could be observed since then, it is important to monitor the genetic diversity, furthermore it highlights the vital role of germplasm collections for the crop diversity conservation. |
EMS induced intercellular chromatin transmigration in Papaver somniferum L.Short CommunicationGirjesh KUMAR, Sana NASEEMCzech J. Genet. Plant Breed., 2013, 49(2):86-89 | DOI: 10.17221/85/2012-CJGPB The phenomenon of chromatin migration was observed during microsporogenesis in an ethyl methane sulphonate (EMS) treated population of poppy, which is an important medicinal plant. Cytomixis occurred through a cytoplasmic channel or by direct fusion of pollen mother cells (PMCs); the former was more recurring than the latter. The process was associated with irregular meiosis. PMCs with differing chromosome numbers from the normal diploid number (2n = 22) through cytomixis may lead to the production of aneuploid and polyploid gametes. An increase in the concentration of EMS had a positive effect on the percentage of PMCs showing cytomixis. In addition to cytomixis, other chromosomal abnormalities were also found. Cytomixis along with the related chromosomal abnormalities largely affected the post-meiotic products resulting in some pollen sterility. |
Questions and avenues for lucerne improvementReviewPaolo Annicchiarico, Carla Scotti, Maria Carelli, Luciano PecettiCzech J. Genet. Plant Breed., 2010, 46(1):1-13 | DOI: 10.17221/90/2009-CJGPB Six crucial questions for lucerne breeders are set up and discussed in relation to the available information. (i) Which width of adaptation? Genotype נlocation interaction is region-specific and may be wide enough to justify breeding for specific adaptation. Genotype נexploitation interaction requires contrasting plant types for mowing and intensive grazing. (ii) Can we breed very drought-tolerant varieties? One drought-tolerant landrace exhibited a drought-avoidance, water-conservation strategy based on limited root development, while large root featured material adapted to favourable environments and/or frequent mowing. (iii) Which selection scheme and variety type? Many schemes were proposed for synthetic varieties, but empirical or theoretical comparisons were limited in number and inference space. Non-additive genetic variation may be exploited by free hybrids (semi-hybrids) through procedures varying in complexity, possibly assisted by marker evaluation. Previous selection of exotic germplasm for adaptation is essential. (iv) How to improve the forage quality? Selection for modified stem morphology (increased internode number, decreased internode length) proved effective. Combined selection for forage yield and leaf/stem ratio seems also feasible. (v) Which opportunities for marker-assisted selection? Linkage maps for lucerne are available but useful markers for forage yield may be site-specific. Bulk segregant analysis is promising in breeding for stress tolerance. (vi) How to exploit genomic information from M. truncatula? This model species can help in developing markers and locating genes which control metabolic pathways, such as saponin content and composition. Information from M. truncatula on marker-trait association for forage yield or tolerance to abiotic stresses may be little exploitable. |
Response of durum wheat (Triticum durum Desf.) growth to salt and drought stressesOriginal PaperRhouma SAYAR, Houcine BCHINI, Mohamed MOSBAHI, Habib KHEMIRACzech J. Genet. Plant Breed., 2010, 46(2):54-63 | DOI: 10.17221/85/2009-CJGPB Two durum wheat (Triticum durum Desf.) cultivars were tested for salt and drought tolerance at germination, seedling emergence and early seedling growth in NaCl and PEG-8000 solutions of different osmotic potentials (-0.2, -0.4, -0.6 and -0.8 MPa). Daily and final germination and emergence percentage, as well as germination and seedling emergence rate, seedling growth, fresh and dry weight were recorded under controlled conditions. Results showed that germination and emergence rates were delayed by both solutions in both cultivars, but Omrabia showed higher germination and emergence rates than BD290273 in NaCl while BD290273 was less affected by NaCl and PEG solutions at the emergence stage. Sodium chloride had a lesser effect on both cultivars in terms of germination rate, emergence rate, final germination and emergence percentage than did PEG-8000. This conclusively proves that the adverse effect of PEG-8000 on germination, emergence and early seedling growth was due to the osmotic effect rather than to the specific ion. Seedling growth was reduced by both stresses. However, NaCl usually caused less damage than PEG to durum wheat seedlings, suggesting that NaCl and PEG acted through different mechanisms. |
Potential of chloroplast genome in plant breedingReviewJana ŘepkováCzech J. Genet. Plant Breed., 2010, 46(3):103-113 | DOI: 10.17221/79/2010-CJGPB Chloroplast engineering (or chloroplast transformation technology, CTT) is a strategy consisting of inserting a transgene into the chloroplast genome of a plant instead of its nuclear genome. CTT brings advantages such as control of the site of gene insertion, high rates of transgene expression and protein accumulation, lack of transmission of the transgene via pollen due to the fact that plastid genes are maternally inherited and an absence of epigenetic effects. Tobacco remains the species most amenable to CTT to date, although chloroplast genetic engineering has also been achieved successfully in crops such as maize, tomato, cotton, potato, rice and sugar beets. Improving agricultural traits such as herbicide and pathogen resistance, resistance to drought, salt tolerance and phytoremediation potential are all promising applications. Molecular pharming is another area of chloroplast engineering with high potential; the production of a wide range of products such as vaccine antigens, pharmaceutical proteins (human somatotropin, human serum albumin, human interferon, monoclonal antibodies) and industrial proteins (avidin, beta casein, liquid crystal polymers, xylanase, anthranilate synthase) is economically beneficial in comparison with bacterial cultivation or animal cell cultures. This review summarises the current status of CCT and its potential economic impact from the viewpoint of high levels of transgene expression and high accumulation of foreign proteins. |
Genetic diversity of selected medicinal plants in protected landscape areas in the Czech RepublicK. Dušek, E. Dušková, K. SmékalováCzech J. Genet. Plant Breed., 2010, 46(10):S34-S36 | DOI: 10.17221/2449-CJGPB Agrimonia eupatoria, Betonica officinalis, Hypericum perforatum, Plantago media, Salvia pratensis and S. verticillata were selected as subjects for a research project studying the genetic diversity of wild medicinal plants in the Czech Republic. Some plants (both in the vegetative form and as seeds) from 26 localities at 5 protected landscape areas around the Czech Republic were transferred to the field nursery in Olomouc; there the contents of the active compounds (essential oil, tannins, hypericin and hyperforin, mucus) were evaluated. The large number of results provides a good opportunity to evaluate the quality of natural medicinal plants for pharmaceutical purposes; with regard to its origin, and to selecting starting materials for both breeding and the production of drugs. |
Possibilities and reality of on-farm conservationV. Holubec, T. Vymyslický, F. PapršteinCzech J. Genet. Plant Breed., 2010, 46(10):S60-S64 | DOI: 10.17221/2670-CJGPB Conservation of crops is based on ex situ collection into gene banks. Additionally, crop's wild relatives can be conserved in situ, and landraces and obsolete cultivars also can be conserved using the on-farm method. The definition and methodology of on-farm conservation is discussed. On-farm conservation has been set up in the Czech Republic as model examples in several institutions dealing with nature protection, education, cultural conservation, as well as by some private farmers. Problems, plus positive and negative experiences are presented. On-farm conservation in open-air-museums in the natur (skansens) as well as in the national parks, seem to be suitable ways forward for the Czech Republic. |
On-farm orchards of fruit treesF. Paprštein, J. Sedlák, V. HolubecCzech J. Genet. Plant Breed., 2010, 46(10):S65-S69 | DOI: 10.17221/2669-CJGPB Four on-farm plantations (KRNAP Vrchlabí, the Orchard of Reconciliation in Neratov, Podyjí National Park, and Šumava National Park) were successfully established in a traditional form, with large orchard trees on seedling rootstocks. Certain accessions (cultivars) for on-farm conservation in the given locality were selected, according to the incidence and presentation of genotypes in these particular areas. This information was obtained by localization of fruit trees in situ and the determination of certain cultivars. Nursery stock production for onfarm plantations is described. Because of the longevity of the plantation, seedling rootstocks were used for the production of planting materials for the on-farm plantations. Techniques of on-farm plantation establishment and orchard management are stated within the paper. Four established on-farm plantations have ensured the long-term preservation of landraces in their original areas. |
Transgene coding of a key enzyme of the glycolytic pathway helps to decrease sugar content in potato tubersShort CommunicationOldřich NAVRÁTIL, Petr BUCHER, Josef VACEKCzech J. Genet. Plant Breed., 2012, 48(1):42-45 | DOI: 10.17221/147/2011-CJGPB Cold-stored potato tubers gradually accumulate reducing sugars. A proposed reason is a cold-induced blocking of glycolysis. The introduction and expression of the bacterial gene Lbpfk coding for cold-tolerant phosphofructokinase might counteract this effect. We have recently introduced this gene into several Czech potato cultivars. The obtained transgenic lines were then tested for three years in field trials. In 17 transgenic lines derived from two of the cultivars we have investigated the accumulation of reducing sugars during two and four months of cold storage. Although in all transgenic lines the sugar content still increased between the 2nd and the 4th month of cold-storage, the level of reducing sugars was in all transgenic lines after both two and four months of cold storage considerably lower than in the original cultivars. The extent of sugar accumulation was also influenced by the parental genotype. No significant differences in sugar accumulation were observed between the transgenic lines from the same parent. |
Hop varieties Bohemie and Saaz LateNew VarietiesV. NesvadbaCzech J. Genet. Plant Breed., 2012, 48(2):98-99 | DOI: 10.17221/24/2012-CJGPB |
Physiologic specialization of wheat leaf rust (Puccinia triticina Eriks.) in the Slovak Republic in 2009-2011Original PaperAlena Hanzalová, Taťána Sumíková, Jozef Huszár, Pavel BartošCzech J. Genet. Plant Breed., 2012, 48(3):101-107 | DOI: 10.17221/28/2012-CJGPB In 2009-2011 virulence of the wheat leaf rust population was studied on Thatcher near-isogenic lines with Lr1, Lr2a, Lr2b, Lr2c, Lr3a, Lr9, Lr11, Lr13, Lr15, Lr17, Lr19, Lr21, Lr23, Lr24, Lr26 and Lr28. Samples of leaf rust were obtained from different parts of the Slovak Republic. A total of 122 wheat leaf rust isolates were analysed. Resistance gene Lr19 was effective to all tested isolates. Virulence to Lr9 was found, however only in one isolate. Gene Lr24 conditioned resistance to almost all rust collections. A lower frequency of virulence to Lr2a and Lr28 was also observed. Nineteen winter wheat cultivars grown in Slovakia were tested with 8 leaf rust isolates. Winter wheat cultivar Bona Dea was resistant to all isolates applied in the greenhouse test. Presence of Lr genes was estimated according to the reactions of the tested cultivars. Presence of Lr10, Lr26, Lr34 and Lr37 was studied by molecular markers. |
Results of the Czech National Ring Tests of disease resistance in wheatScientific ReportsJana CHRPOVÁ, Václav ŠÍP, Pavel BARTOŠ, Alena HANZALOVÁ, Jana PALICOVÁ, Lenka ŠTOČKOVÁ, Lubomír ČEJKA, Irena BÍŽOVÁ, Petr LAML, Tomáš NOVÁČEK, Pavel HORČIČKACzech J. Genet. Plant Breed., 2012, 48(4):189-199 | DOI: 10.17221/173/2012-CJGPB In this contribution actual results of the Czech national ring tests of disease resistance in wheat are presented that are performed at 3-5 locations each year. Special attention was paid to possibilities of increasing resistance to rusts, powdery mildew, Fusarium head blight and brown leaf spot diseases. New sources of resistance to the above-mentioned diseases were detected and described. Achievements and prospects of wheat breeding for resistance to these diseases, as well as to other important diseases and pests (common and dwarf bunt, eyespot and stem base diseases, barley yellow dwarf virus, orange wheat blossom midge) are discussed. |
QTL analysis for yield related traits using populations derived from an indica-japonica hybrid in rice (Oryza sativaL.)Original PaperLutfor Rahman, Most Sakina Khanam, Hee-Jong KohCzech J. Genet. Plant Breed., 2008, 44(3):93-104 | DOI: 10.17221/16/2008-CJGPB Introgression has been achieved from a wild species Oryza minuta (2n = 48, BBCC, Acc No.101141) into O. sativa subsp. indica IR71033-121-15. This introgression line was developed at International Rice Research Institute (IRRI) through embryo rescue as well as three backcrosses using IR31917-45-3-2 as a recurrent parent. These two IR lines resemble each other but differ in several important agronomic traits, which can be attributable to O. minuta introgressions. Out of 530 STS markers tested for introgression analysis, at least 14 introgressed chromosomal segments from O. minuta were detected throughout 12 chromosomes. Most of the introgressed segments were quite small in size, as they were detected by single markers and flanking markers were negative for introgressions. A population from the cross between japonica cultivar Junambyeo and introgressed indica line IR71033-121-15, consisting of 146 plants, was evaluated for ten agronomic traits. Genotyping of F2 lines and phenotyping from both F2 and F3 were considered for QTL analysis. A total of 11 single-locus QTLs (S-QTLs) were identified for ten traits, i.e. days to heading (DTH), panicle number (PN), spikelet fertility (SF), panicle length (PL), spikelet per panicle (SPP), grain length (GL), grain width (GW), grain length to width ratio (GLW) and grain thickness (GT) in both populations. The O. minuta derived alleles of QTLs, spp6, gl3, glw3, glw5 and t12 were detected in both populations indicating robust QTLs for these traits. QTLs from O. minuta introgression could be new sources of natural genetic variation for genetic improvement of rice. |
Yield stability and resistance to leaf spot diseases and rosette in groundnutOriginal PaperGodfrey Akpan IWO, P.E. OLORUNJUCzech J. Genet. Plant Breed., 2009, 45(1):18-25 | DOI: 10.17221/30/2008-CJGPB Twenty-three advanced groundnut lines were evaluated for yield and resistance to early leaf spot (Mycosphaerella arachidis Deighton), late leaf spot (Mycosphaerella berkeleyi W.A. Jenkins) and rosette virus in on-station trials in 2001 and 2002. All the early groundnut lines were relatively resistant to rosette virus, early leaf spot and late leaf spot except ICGV-SM-93523 and ICGV-SM-93525, which were susceptible to late leaf spot. The medium maturing lines showed mostly higher levels of diseases, except MS16-791, which performed very well against all three diseases. The late groundnut lines were mostly susceptible to one or more of the diseases, except 49-85A and ICGV-SM-93532. Nine groundnut lines, combining high yield and resistance against all three diseases, were selected for on-farm trials at four locations in 2004 and 2005. In the on-farm trials all the nine selected lines were also resistant or highly resistant to rosette and both early and late leaf spot, while the local check, Makodi, was susceptible to all three diseases in both the on-station and on-farm trials. The analysis of yield data obtained at the eight environments, based on the linear statistical model yij = μ + ai+ ej + rij, estimated the genetic variance about three times higher than the residual variance. Still better results were obtained with the multiplicative model yij = μaibj+ ej + rij, where the genetic variance was more than four times higher than the residual variance and a still better differentiation of cultivars was thus possible. Significant differences in cultivar stability, expressed as the variation coefficient of the ai estimates (i.e. the variation of Standardised Relative Yields) from the multiplicative model across the eight environments, were observed. The check cultivar Makodi, though quite stable, was the lowest yielding of all tested ones. The groundnut line ICGV-1S-96805 combined very high yielding capacity and outstanding disease resistance with good, though not the highest, yield stability. |
Reaction of wheat varieties to infection with barley yellow dwarf virus and prospects for resistance breedingOriginal PaperOndřej Veškrna, Jana Chrpová, Václav Šíp, Tibor Sedláček, Pavel HorčičkaCzech J. Genet. Plant Breed., 2009, 45(2):45-56 | DOI: 10.17221/32/2009-CJGPB The reaction of winter and spring wheat to infection with barley yellow dwarf virus (BYDV-PAV) was evaluated in three-year small-plot field trials on 71 wheat varieties registered in the Czech Republic and at two locations for two years on 63 selected potential sources of resistance. Disease symptoms (VSS) were visually recorded using a 0-9 scale and the percent reduction of grain weight per spike (GWS-R) was measured on twenty plants per plot. The evaluation showed that among the registered varieties of winter and spring wheat no variety had a high resistance to BYDV (with VSS lower than 3.5). GWS-R ranged between 24% and 60%. Higher variability in VSS was detected for the registered varieties of spring wheat compared to winter wheat. Among the registered varieties of winter wheat, Saskia, Rialto, Meritto, Rexia, and Svitava, as well as the spring wheat Leguan, received the best long-term evaluations. The highest level of resistance was detected for the PSR 3628 line (a hybrid of wheat and couch-grass), but in connection with a low agronomic value. The WKL91-138 line of spring wheat and some varieties (lines) with the detected moderate level of resistance, in particular, could offer good prospects for use in breeding. The presence of the Bdv2 gene was expressed only in the reduction of virus content on the 11th day after inoculation. Nevertheless, genotypes carrying this gene were evaluated in field trials as susceptible or very susceptible to infection with the Czech PAV isolate. Similarly, the presence of the Bdv1 gene detected with the help of WMS130 marker was no assurance of an increased level of resistance to BYDV. Hybridological analyses of crosses with the WKL91-138 line showed a polygenic nature of inheritance. Thus, the marker-assisted selection does not obviously promise success without a focus on detecting a larger number of QTLs. |
Cytogenetical investigations in colchicine-induced tetraploids of Cyamopsis tetragonoloba L.Original PaperSangeeta BEWAL, Jigyasa PUROHIT, Arun KUMAR, Rajkumari KHEDASANA, Satyawada Rama RAOCzech J. Genet. Plant Breed., 2009, 45(4):143-154 | DOI: 10.17221/41/2009-CJGPB Successful induction of autotetraploidy has been achieved in five accessions of Cyamopsis tetragonoloba L. The diploid seedlings of these accessions were treated with different concentrations of aqueous colchicine using the cotton-swab method for 10-18 hours within 2-3 days. The highest percentage of success was recorded when the seedlings were treated with 0.2% colchicine for 10 h within two days. The synthesized plants showed remarkable enhancement in several morphological and floral characters making them more robust and better plants from the food and feed aspect. Cytologically, quadrivalent frequency ranging from 3.18 to 5.45 and univalent frequency ranging from 0.08 to 1.10 were characteristic of the colchicine-induced tetraploids. Among all the associations, bivalent chromosome associations were observed more frequently (2.95 to 6.04). The anaphase I and II disjunction of bivalents/chromosomes was leading more or less regularly and equally to the formation of at least few seeds from some of the synthesized plants. Significant enhancement in morphological traits as revealed in colchicine-induced tetraploid plants having a better food and feed value and normal meiotic behaviour of synthesized autotetraploids leading to a good seed set may ultimately result in the genetic improvement of Cyamopsis tetragonoloba. |
Standard descriptors and EURISCO developmentI. FaberováCzech J. Genet. Plant Breed., 2010, 46(10):S106-S109 | DOI: 10.17221/1521-CJGPB The paper gives information about both the genesis, and a survey of, the descriptors used for the documentation of plant genetic resources held in ex situ crop collections. The first international documentation standards were developed by the FAO in the 1950s. In 1974, a specific body for plant genetic resources, the IBPGR (International Board for Plant Genetic Resources), was established within the FAO. Since the 1970s, the descriptor lists for main crop collections have been developed, including passport descriptor sets. For the most part, the passport descriptors were common to all crops, with only slight differences. In 1997, the first attempt to create a standard set of descriptors resulted in 24 passport descriptors developed by FAO and IPGRI (International Plant Genetic Resources Institute) working in cooperation. In 2001, the official Multi-Crop Passport Descriptor list (MCPD) was published, including a revised standard set of 28 descriptors. The European ex situ crop catalogue (EURISCO) enlarged the standard set of passport descriptors by adding 6 additional fields in 2002; and another 2 new descriptors were added in November of 2008. A global level of data compatibility is preferred; therefore projects aimed at world-wide utilization and standardization of systems, such as GRINGlobal, and Accession-Level Information System (ALIS), are supported. |
Post-harvest content of free titratable acids in the grain of proso millet varieties (Panicum milliaceum L.), and changes during grain processing and storageV. Dvořáček, D. Janovská, L. Papoušková, E. BicanováCzech J. Genet. Plant Breed., 2010, 46(10):S90-S95 | DOI: 10.17221/699-CJGPB A triennial evaluation of the content of titratable acids (TA) in grain was carried out on 12 varieties of proso millet (Panicum miliaceum L.). The model variety, Mironovskoe 94, harvested in 2004, was used for the monitoring of sensory changes in TA content, in relationship to different storage conditions and the application of different grain processing methods. The Czech state norm (CSN 56 0512-9 1995) Determination of Titratable Acids, with a slight modification, was used as the standard method. The TA contents in dry matter varied between 39 and 78 mmol/kg of grain dry matter, and significant differences between varieties and experimental years were found. The method of proso millet processing had a key role in the final sensitivity to rancidity. The storage conditions had a much lower influence on TA content than the processing technology. The clearly detected sensory changes found in scoured grains corresponded with TA contents within the range of 90 to106 mmol/kg. The monitoring of the TA content can be considered as a suitable tool for the prediction of rancidity processes in millet grains. |
Expression of resistance to Ramularia leaf spot in winter barley cultivars grown in conditions of the Czech RepublicShort CommunicationPavel Mařík, Zdenek Šnejdar, Pavel MatušinskyCzech J. Genet. Plant Breed., 2011, 47(1):37-40 | DOI: 10.17221/34/2010-CJGPB The fungus Ramularia collo-cygni is increasingly important as the causal agent of Ramularia leaf spot (RLS), a novel leaf spot disease of barley. The work aimed to identify gene resources suitable for developing new breeding lines of winter barley with improved resistance. During the first experimental period (2001-2005), RLS incidence was monitored in 711 cultivars and advanced breeding lines. Differences were detected in the intensity of symptomatic expression, but no material showed high resistance. During the second experimental period (2006-2009), response to natural RLS infection was evaluated in 19 winter barley cultivars (12 six-row and 7 two-row) registered in the Czech Republic. Highest susceptibility was detected in 6-row cvs. Luran, Laverda and Wendy while cvs Breunskylie (2-row), Merlot and Highlight (both 6-row) showed relatively lower disease incidence. High resistance was not detected. On average, 2-row cultivars showed lower intensity than 6-row cultivars and significant variation was observed among years. |
Dissimilarity of barley powdery mildew resistances Lomerit and Heils HannaOriginal PaperAntonín DREISEITLCzech J. Genet. Plant Breed., 2011, 47(3):95-100 | DOI: 10.17221/45/2011-CJGPB The resistance Heils Hanna (HH) was postulated in several tens of 471 previously tested winter barley cultivars. In this paper, new tests on 29 of these cultivars are reported. Thirty-two reference isolates of Blumeria graminis f.sp. hordei held in the pathogen genebank at the Agricultural Research Institute in Kromeriz, Ltd. including a Japanese isolate and five Israeli isolates were used for response tests. However, the resistance HH conferred by the gene Mla8 and herein characterised by reaction type 0 to an old Japanese isolate known as Race I was now postulated only in four cultivars. In the other 25 cultivars another resistance, characterised by reaction type 0 to Race I and also to two Israeli isolates, was detected. In addition to the two mentioned resistances, eight known (Bw, Dr2, Ha, IM9, Ln, Lv, Ra and Sp) resistances were found in the set examined. Lomerit was the only registered cultivar tested here in which the newly detected resistance was present alone, therefore, it is recommended that this resistance be designated Lo. |
Wheat science into the 21st century - challenges and opportunitiesH.-J. BraunCzech J. Genet. Plant Breed., 2011, 47(10):S1-S2 | DOI: 10.17221/3246-CJGPB |
Evaluation of CIMMYT germplasm for resistance to leaf spotting diseases of wheatP.K. SINGH, E. DUVEILLER, R.P. SINGHCzech J. Genet. Plant Breed., 2011, 47(10):S102-S108 | DOI: 10.17221/3263-CJGPB The leaf spotting disease complex is a major biotic constrain in enhancing grain production in the major wheat growing regions. Two leaf spotting diseases, tan spot, caused by an ascomycete fungus Pyrenophora tritici-repentis, and Stagonospora nodorum blotch besides causing average yield losses of 5-10%, cause significant losses in grain quality by red smudge, black point and grain shriveling. Conservation agriculture in combination with wheat monoculture involving cultivation of susceptible cultivars has resulted in frequent onset of leaf spots epidemics worldwide. Development of resistant wheat cultivars, in conjunction with crop rotation, will provide an effective, economical, and environmentally safe means of controlling leaf spot. International Maize and Wheat Improvement Center (CIMMYT), Mexico has initiated major efforts to mitigate the threat of tan spot. Efforts include screening of wheat germplasm, identification of new sources of resistance, characterization of new tan spot resistance genes through classical and molecular genetic analysis, incorporation of resistance into adapted cultivars, and assessing the variability in the tan spot fungus. Screening studies reveal that elite CIMMYT germplasm has high level of resistance to tan spot caused by P. tritici-repentis race 1. These germplasm have diverse genetic make-up and the resistance is likely broad based. Association mapping studies done with CIMMYT germplasm reconfirmed the presence of previously identified genomic regions for tan spot resistance; however, novel genomic regions on long arm of chromosomes 6A and 7B have also been identified. Studies done to date indicate that CIMMYT germplasm possess high level diverse genetic based resistance to tan spot of wheat. Efforts are in place to develop desired wheat cultivars with tan spot resistance. Virulence studies indicate presence of P. tritici-repentis race 1 only with some variability in level of toxin Ptr ToxA produced in each of the 76 isolates studied. |
