Lines Of Cv Research Articles

Constructed Rice Tracers Identify the Major Virulent Transcription Activator-Like Effectors of the Bacterial Leaf Blight Pathogen

Xanthomonas oryzae pv. oryzae (Xoo) injects major transcription activator-like effectors (TALEs) into plant cells to activate susceptibility (S) genes for promoting bacterial leaf blight in rice. Numerous resistance (R) genes have been used to construct differential cultivars of rice to identify races of Xoo, but the S genes were rarely considered. Different edited lines of rice cv. Kitaake were constructed using CRISPR/Cas9 gene-editing, including single, double and triple edits in the effector-binding elements (EBEs) located in the promoters of rice S genes OsSWEET11a, OsSWEET13 and OsSWEET14. The near-isogenic lines (NILs) were used as tracers to detect major TALEs (PthXo1, PthXo2, PthXo3 and their variants) in 50 Xoo strains. The pathotypes produced on the tracers determined six major TALE types in the 50 Xoo strains. The presence of the major TALEs in Xoo strains was consistent with the expression of S genes in the tracers, and it was also by known genome sequences. The EBE editing had little effect on agronomic traits, which was conducive to balancing yield and resistance. The rice-tracers generated here provide a valuable tool to track major TALEs of Xoo in Asia which then shows what rice cultivars are needed to combat Xoo in the field.

Biological and molecular interactions between bell pepper endornavirus and two tobamoviruses

Peppers (Capsicum spp.) are native plants to the Americas. They are cultivated worldwide for direct human consumption and industrial purposes. Peppers can be infected by acute plant viruses, which cause a variety of diseases and crop losses. However, many Capsicum species can also be infected by persistent viruses. These are emerging viruses and they do not cause apparent disease and are transmitted only vertically. Using two near-isogenic lines of bell pepper cv. Marengo, biological and molecular interactions between the persistent virus bell pepper endornavirus (BPEV) and two acute viruses, pepper mild mottle virus (PMMoV) and tobacco mild green mosaic virus (TMGMV), were evaluated by symptom expression, enzyme-linked immunosorbent assay, and RT-qPCR. The relative titer of BPEV decreased at least two-fold at 14 days after infection when BPEV-infected plants were single infected with TMGMV or in mixed infection of PMMoV and TMGMV. The presence of BPEV was associated with symptom reduction in pepper plants infected with single and mixed infections of PMMoV and TMGMV. This suggests that the ubiquitous infection of BPEV may trigger the plant immune response, and therefore, BPEV is active when the plant is infected with PMMoV and/or TMGMV.

Agronomic characteristics and genetic relationship of putative transgenic rice lines of cv. Fatmawati with the Glu-1Dx5 transgene

Abstract. Carsono N, Prayoga GI, Sari S, Rachmadi M. 2021. Agronomic characteristics and genetic relationship of putative transgenic rice lines of cv. Fatmawati with the Glu-1Dx5 transgene. Biodiversitas 23: 291-298. Transgenic rice lines cv. Fatmawati with the Glu-1Dx5 transgene (encoding high molecular weight glutenin sub-unit Dx5 from bread wheat) has been produced in order to improve dough functionality of rice flour. These lines have reached T1 (transformant-1) dan T2 (transformant-2) generations. Some transgenic rice plants obtained from in vitro culture and transformation events frequently show phenotypic and genotypic variations from the original plants, thus evaluation of agronomic traits of these transgenic rice is highly important in order to obtain rice genotypes with the best agronomic traits that will be integrated into rice breeding program. Nine transgenic rice lines and two check lines, i.e. seed-derived and callus-derived rice lines, were used in this experiment. A comparison between transgenic rice traits with those of non-transgenic checks was done by student’s t-test and relationship among transgenic rice lines was evaluated by UPGMA (Unweighted Pair Group Method with Mean Arithmetic) method using NT Sys (Numerical Taxonomy and Multivariate Analysis System). Results indicated that agronomic traits of transgenic rice lines were similar to those of non-transgenic check except for number of productive tillers (T2-11, T2-12, T2-20), the maximum number of tillers (T2-7, T2-11, T2-12, T2-20), number of filled grains (T1-45) and days to maturity (all T2 lines). It suggests that somaclonal variations, gene insertional effect, genetic and epigenetic mutations might occur. Genetic relationship between putative transgenic and non-transgenic checks was closely related, although somaclonal variants were found. The selected transgenic rice lines will be incorporated into rice breeding programs.

Marker-Assisted Development and Evaluation of Monogenic Lines of Rice cv. Kaohsiung 145 Carrying Blast Resistance Genes.

Rice blast is a serious threat to global rice production. Large-scale and long-term cultivation of rice varieties with a single blast resistance gene usually leads to breakdown of resistance. To effectively control rice blast in Taiwan, marker-assisted backcrossing was conducted to develop monogenic lines carrying different blast resistance genes in the genetic background of an elite japonica rice cultivar, Kaohsiung 145 (KH145). Eleven International Rice Research Institute (IRRI)-bred blast-resistant lines (IRBLs) showing broad-spectrum resistance to local Pyricularia oryzae isolates were used as resistance donors. Sequencing analysis revealed that the recurrent parent, KH145, does not carry known resistance alleles at the target Pi2/9, Pik, Pita, and Ptr loci. For each IRBL × KH145 cross, we screened 21 to 370 (average of 108) plants per generation from the BC1F1 to BC3F1/BC4F1 generation. A total of 1,499 BC3F2/BC4F2 lines carrying homozygous resistance alleles were selected and self-crossed for four to six successive generations. The derived lines were also evaluated for background genotype using genotyping by sequencing, for blast resistance under artificial inoculation and natural infection conditions, and for agronomic performance in multiple field trials. In Chiayi and Taitung blast nurseries in 2018 to 2020, Pi2, Pi9, and Ptr conferred high resistance, Pi20 and Pik-h moderate resistance, and Pi1, Pi7, Pik-p, and Pik susceptibility to leaf blast; only Pi2, Pi9, and Ptr conferred effective resistance against panicle blast. The monogenic lines showed agronomic traits, yield, and grain quality similar to those of KH145, suggesting the potential of growing a mixture of lines to achieve durable resistance in the field.

Obtaining Transgenic Potato Plants Expressing the Human Lactoferrin Gene and Analysis of Their Resistance to Phytopathogens

The human lactoferrin gene was transferred into genomes of several potato (Solanum tuberosum) cultivars of Ukrainian breeding using the Agrobacterium-mediated transformation. The plasmid vector pBIN35LF carrying the human lactoferrin gene hLf controlled by the 35S cauliflower mosaic virus promoter (CaMV35S) and the octopine synthase terminator, as well as the selective marker neomycin phosphotransferase II gene (nptII) conferring the resistance to kanamycin, was used. As a result of selection, 44 lines of Vernisage, 26 lines of cv. Levada, 25 lines of cv. Svitanok Kyivskyi, and 16 lines of cv. Zarevo cultivars resistant to 100 mg/L of kanamycin were obtained. PCR and Western blot analyses were carried out for transformed lines with primers specific to the hLf gene and a monoclonal antibody against lactoferrin to confirm the transgenic nature of selected tomato plants and hLf gene expression. The selected transgenic potato lines were tested for resistance to bacterial and fungal phytopathogens. The disk diffusion assay revealed that the juice of transgenic potato lines possesses an antibacterial effect against phytopathogenic bacteria Ralstonia solanacearum (causing potato brown rot) and Clavibacter michiganensis subsp. sepedonicus (causing potato ring rot). The resistance of transgenic potato plants to late blight was investigated by in vitro infection of plants with the Phytophthora infestans isolate. As a result, it was found that the obtained transgenic potato lines have enhanced resistance to P. infestans as compared to the control. Thus, the obtained data show that the transfer of the hLf gene into the potato genome enhances potato’s resistance to bacterial and fungal pathogens.

Challenges in the Processing Line of Spanish Style cv. Chalkidiki Green Table Olives Spontaneously Fermented in Reduced NaCl Content Brines

AbstractIn this work, the effect of different treatments using selected combinations of chloride salts (NaCl, KCl, CaCl2, MgCl2) in fermentation brine to assess the safety, quality, and nutritional value of the Spanish style cv. Chalkidiki green table olives spontaneously fermented is studied. Examination of safety parameters (bacteria/yeasts, pH, acidity) and changes in olive color and texture characteristics in brines during fermentation, and in mineral content of olives upon storage up to 12 months, is conducted using appropriate methods. Sensory evaluation takes place in certain cases. Among the tested salt combinations, those of 4.08% NaCl, 2.8% KCl, 1% CaCl2, and 0.12% MgCl2 (w/v) are found to be the most effective regarding safety, color, texture, and taste. Findings support that Spanish style cv. Chalkidiki green olives can be spontaneously fermented in reduced NaCl content brine. The 50% lower NaCl content of the fermented olives compared with that in traditionally fermented ones suggests that reformulation of cv. Chalkidiki green table olives by safe intervention is feasible.Practical Applications: cv. Chalkidiki green table olives are of high importance for the Greek economy. Traditionally they are spontaneously fermented in NaCl brine (8% w/v). Partial replacement of NaCl content with other salts in such a line results in a product acceptable in terms of safety and quality characteristics. The Greek table olive industry may profit from the findings in an attempt to remodel the traditional spontaneous fermentation in green olive processing according to international dietary guidelines.

Elevated CO2 not increased temperature has specific effects on soil nematode community either with planting of transgenic Bt rice or non-Bt rice.

BackgroundTransgenic Bt rice has not been approved for commercial cultivation because of the fierce public debate on food safety, biosafety regulation and ecological risk. Meanwhile, the concentration of CO2 and temperature in the atmosphere, as important environmental factors affecting the persistence of exogenous Bt protein, have increased. Elevated CO2, increased temperature, the planting of transgenic Bt rice and their interactions may further influence the structure and complexity of soil food web. However, the effects of transgenic Bt rice planting on soil organism remain largely unexplored before its commercial production especially under global climate change.MethodsHere, we assessed the influences of transgenic Bt rice (cv. HH with fused Cry1Ab/Cry1Ac in contrast to its parental line of non-Bt rice cv. MH63) on soil nematode communities under the conditions of elevated CO2 concentration and increased temperature for 2 years of 2016 and 2017 in open-top chambers located in Ningjin County, Shandong Province of China.ResultsElevated CO2 concentration remarkably increased the abundance of fungivores and significantly decreased their nematode channel ratio (NCR) and enrichment index (EI) irrespective of rice variety (transgenic Bt rice or non-Bt rice) or temperature (normal temperature or increased temperature). Additionally, rice variety and temperature did not significantly change soil nematode composition, abundance and ecological indices (including total maturity index (∑MI), Shannon diversity (H′), structure index (SI), NCR and EI). However, apparent seasonal changes were observed in theses aforementioned variables.DiscussionThese results suggested that atmospheric CO2 concentration but not temperature or rice variety has great impacts on soil nematode community, especially fungivores.

Arbuscular mycorrhizal fungi alter the food utilization, growth, development and reproduction of armyworm (Mythimna separata) fed on Bacillus thuringiensis maize.

BackgroundThe cultivation of Bt maize (maize genetically modified with Bacillus thuringiensis) continues to expand globally. Arbuscular mycorrhizal fungi (AMF), an important kind of microorganism closely related to soil fertility and plant nutrition, may influence the ecological risk of target lepidopteran pests in Bt crops.MethodsIn this study, transgenic Bt maize (Line IE09S034 with Cry1Ie vs. its parental line of non-Bt maize cv. Xianyu335) was inoculated with a species of AMF, Glomus caledonium (GC). Its effects on the food utilization, reproduction and development of armyworm, Mythimna separata, were studied in a potted experiment from 2017 to 2018.ResultsGC inoculation increased the AMF colonization of both modified and non-modified maize, and also increased the grain weight per plant and 1,000-grain weight of modified and non-modified maize. However, the cultivation of Bt maize did not significantly affect the AMF colonization. The feeding of M. separata with Bt maize resulted in a notable decrease in RCR (relative consumption rate), RGR (relative growth rate), AD (approximate digestibility), ECD (efficiency of conversion of digested food) and ECI (efficiency of conversion of ingested food) parameters in comparison to those observed in larvae fed with non-Bt maize in 2017 and 2018, regardless of GC inoculation. Furthermore, remarkable prolongation of larval life span and decreases in the rate of pupation, weight of pupa, rate of eclosion, fecundity and adult longevity of M. separata were observed in the Bt treatment regardless of GC inoculation during the two-year experiment. Also, when M. separata was fed with Bt maize, a significant prolongation of larval life and significant decreases in the pupal weight, fecundity and adult longevity of M. separata were observed when inoculated with GC. However, it was just the opposite for larvae fed with non-Bt maize that was inoculated with GC. The increased percentage of larval life-span, the decreased percentages of the food utilization, and the other indexes of reproduction, growth, and development of M. separata fed on Bt maize relative to non-Bt maize were all visibly lower when under GC inoculation in contrast to the CK.DiscussionIt is presumed that Bt maize has a marked adverse impact on M. separata development, reproduction and feeding, especially when in combination with the GC inoculation. Additionally, GC inoculation favors the effectiveness of Bt maize against M. separata larvae by reducing their food utilization ability, which negatively affects the development and reproduction of the armyworm. Thus, Bt maize inoculated with AMF (here, GC) can reduce the severe threats arising of armyworms, and hence the AMF inoculation may play an important ecological functions in the field of Bt maize ecosystem, with potentially high control efficiency for the target lepidopteran pests.

Development of 1AS.1AL-1DL durum wheat chromosome carrying Glu-D1a locus encoding high molecular weight glutenin subunits 2 + 12

High molecular weight glutenin subunits (HMW-GS) are well-known to directly influence the bread wheat quality. In a previous paper, our group reported the replacement of the locus Glu-A1 by the locus Glu-D1—allele Glu-D1a encoding the HMW-GS (2–12)—in a partial isohomoeoallelic lines of the French bread wheat variety cv. Courtot. We plan to exploit the novel translocated 1AS.1AL-1DL chromosome in durum wheat in order to develop durum lines presenting novel properties. The translocated chromosome was first introduced into durum wheat. However, as the distal translocated 1DL segment represents 25% (i.e., 84 Mb) of the recombinant 1AL length, it appeared worthwhile to shorten it through homoeologous recombination induced by the ph1c mutation. Two rounds of recombination were made. The shortest interstitial 1DL segment detected through SNP genotyping measured 9.19 Mb and could not be visualized by genomic in situ hybridization. Such reduced transfer not previously achieved hitherto provides regularity of the meiotic pairing and will allow the use of those subunits absent in durum wheat species for direct exploitability in breeding.

Overexpression of the Anthocyanidin Synthase Gene in Strawberry Enhances Antioxidant Capacity and Cytotoxic Effects on Human Hepatic Cancer Cells.

Food fortification through the increase and/or modulation of bioactive compounds has become a major goal for preventing several diseases, including cancer. Here, strawberry lines of cv. Calypso transformed with a construct containing an anthocyanidin synthase (ANS) gene were produced to study the effects on anthocyanin biosynthesis, metabolism, and transcriptome. Three strawberry ANS transgenic lines (ANS L5, ANS L15, and ANS L18) were analyzed for phytochemical composition and total antioxidant capacity (TAC), and their fruit extracts were assessed for cytotoxic effects on hepatocellular carcinoma. ANS L18 fruits had the highest levels of total phenolics and flavonoids, while those of ANS L15 had the highest anthocyanin concentration; TAC positively correlated with total polyphenol content. Fruit transcriptome was also specifically affected in the polyphenol biosynthesis and in other related metabolic pathways. Fruit extracts of all lines exerted cytotoxic effects in a dose/time-dependent manner, increasing cellular apoptosis and free radical levels and impairing mitochondrial functionality.

The effects of sodium azide on seed germination and seedling growth of chili pepper (Capsicum annum L. cv. Landung)

This study was aimed to determine the effects of sodium azide on the performance of chili pepper. Dry seeds from pure lines of chili pepper cv. Landung were used in this experiment. Each set containing 50 seeds was placed in nylon fishner bags, washed in flowing water and soaked in distilled water for four hours. After soaking, four sets of seeds were dabbed dry with tissue paper and were treated for two hours at 30 0C in appropriate solution of 0, 0.10, 0.20, 0.40, 0.80, 1.60 mM sodium azide with phosphate buffer at pH 3. After treatment, the seeds were germinated in plastic boxes containing sterilized sand and kept under laboratory condition by supplied with water everyday. The seeds for M1 germination percentage, seedling height, plant height and number of leaves were recorded 30 days and 60 days after treatment, respectively. Seeds which radicle emerged were considered germinated, the seedling and plant height were measured from the tip of primary root to the base of the first leaf pair, and the number of leaves were counted for only fully expanded leaves. A completely randomized block design in four replicates was used throughout the experiment. Data obtained were analysed for range, mean, standard of deviation, and percent of control using Microsoft Office Excel 2007 software. It was concluded that different doses of sodium azide influenced the performances of chili pepper cv. Landung. Very low doses of sodium azide (0-1.60 mM) might be used to study the improvement of chili pepper diversity.

Impact of compatible and incompatible barley—Blumeria graminis f.sp. hordei interactions on chlorophyll fluorescence parameters

Interactions between different barley genotypes and the fungal pathogen Blumeria graminis f.sp. hordei (Bgh) have a specific impact on the crop physiology. Within the context of plant resistance phenotyping, it is relevant to investigate early host–pathogen interactions to avoid the crop infestation. Analyzing different parameters of the photosynthesis apparatus gives in-depth information of the plant’s health status and can be used for a spatial and temporal assessment of interaction types during plant–pathogen infestation. In the present study, experiments were performed with a near-isogenic line of barley cv. Ingrid WT (susceptible), mlo3 (papilla-based resistance) as well as a near-isogenic line of cv. Pallas, containing the Mla1 (hypersensitive response-based resistance) gene. After inoculation with Bgh isolate K1, the leaves were measured daily using chlorophyll fluorescence imaging. Inoculated, susceptible wild-type leaves showed a reduced effective quantum yield of the photosystem II (ΦPSII) already 1 day after inoculation. In accordance with the quantum yield reduction, the non-photochemical quenching (NPQ) increased, indicating thermal dissipation of excess energy. The changes of ΦPSII and NPQ represent modifications of the leaf metabolism to aid the fungal nutrition uptake, which is influenced by Bgh. By analyzing these parameters, it was also possible to indicate resistance reactions of mlo3 and Mla1 barley genotypes against Bgh. During papilla formation in mlo3 leaves, ΦPSII revealed the lowest values. In contrast, inoculated Mla1 leaves showed the lowest NPQ. The present study proofs that chlorophyll fluorescence imaging is a valuable tool for investigating early plant–pathogen interaction noninvasively. Furthermore, this phytopathology study uses chlorophyll fluorescence imaging, chlorophyll extraction and microscopic observations to characterize the interaction response of different genotypes to an Bgh infection.

Improvement of Flax Drought Tolerance Using Gene Transfer

Attempt was made to produce transgenic cell lines of flax cv. Blanka tolerant to drought stress. Genetic transformation systems were used to incorporate the DREB2A gene, as the specific gene for drought stress tolerance. In biolistic transformation, hypocotyl segments were bombarded with DREB2A and GFP genes at particle flight distance of 9 cm and rupture disc pressure of 1300 psi. The expression of the gene was observed under a light microscope after 24 and 48 hrs. In Agrobacterium?mediated transformation, the hypocotyl segments were incubated overnight with Agrobacterium culture at five optical density OD600 i.e. 0.2, 0.4, 0.6, 0.8 and 1 for 30 min with occasional stirring. Later, the explants were transferred to a selection regeneration medium supplemented with 50 mg/dm3 hygromycin and 300 mg/dm3 cefotaxime and subcultured every two weeks on a new selection medium. Molecular analysis confirmed the expression of the target DREB2A gene in flax genome.Plant Tissue Cult. & Biotech. 26(2): 197-207, 2016 (December

Physiological and molecular characteristics of two ploidy mutants in Myrica rubra cv. Dongkui

In this study, two ploidy mutant lines of Myrica rubra cv. Dongkui (DK) were identified and named as DB1 and DB2. The floral organ, leaf cell structure, ploidy, and number of chromosomes of the two mutants were investigated. Meanwhile, anthocyanin contents at different developmental stages were analyzed, and the Cy-3-glu contents of DB1 and DB2 at the full ripe stages are significantly higher than that of DK by 27.84 and 23.51%, respectively. Furthermore, 6 RNA libraries at two developmental stages (young fruit stage and full ripe stage) were built for RNA-Seq. By mapping to the reference database, 28 407, 28 043, and 28 683 genes were detected in the young fruit of DB1, DB2, and DK, respectively, while 28 040, 22 256, and 27 351 genes were detected in the full ripe stage, respectively. There were 281 differentially expressed genes between DB1 and DK, with 123 and 158 genes up-regulated and down-regulated, respectively, and 47 differentially expressed genes between DB2 and DK, of which 8 and 39 genes were up-regulated and down-regulated. Using real-time PCR, the expression levels of the eight functional genes at different developmental stages of the fruit were also analyzed. These comprehensive analyses showed that both mutants are different from DK, which is the result of natural doubling of ploidy, thereby generating a pleiotropic effect. As we known, it is the first report to study the relationship between bayberry ploidy alterations and genes involved in regulation of fruit mutations, which will help to identify the morphological and cytological characteristics of M. rubra germplasm, and provide a theoretical basis and technical support for genetic improvement and creation of breeding resources.

Development and Molecular Cytogenetic Identification of a Novel Wheat-Leymus mollis Lm#7Ns (7D) Disomic Substitution Line with Stripe Rust Resistance.

Leymus mollis (2n = 4x = 28, NsNsXmXm) possesses novel and important genes for resistance against multi-fungal diseases. The development of new wheat—L. mollis introgression lines is of great significance for wheat disease resistance breeding. M11003-3-1-15-8, a novel disomic substitution line of common wheat cv. 7182 –L. mollis, developed and selected from the BC1F5 progeny between wheat cv. 7182 and octoploid Tritileymus M47 (2n = 8x = 56, AABBDDNsNs), was characterized by morphological and cytogenetic identification, analysis of functional molecular markers, genomic in situ hybridization (GISH), sequential fluorescence in situ hybridization (FISH)—genomic in situ hybridization (GISH) and disease resistance evaluation. Cytological observations suggested that M11003-3-1-15-8 contained 42 chromosomes and formed 21 bivalents at meiotic metaphase I. The GISH investigations showed that line contained 40 wheat chromosomes and a pair of L. mollis chromosomes. EST-STS multiple loci markers and PLUG (PCR-based Landmark Unique Gene) markers confirmed that the introduced L. mollis chromosomes belonged to homoeologous group 7, it was designated as Lm#7Ns. While nulli-tetrasomic and sequential FISH-GISH analysis using the oligonucleotide Oligo-pSc119.2 and Oligo-pTa535 as probes revealed that the wheat 7D chromosomes were absent in M11003-3-1-15-8. Therefore, it was deduced that M11003-3-1-15-8 was a wheat–L. mollis Lm#7Ns (7D) disomic substitution line. Field disease resistance demonstrated that the introduced L. mollis chromosomes Lm#7Ns were responsible for the stripe rust resistance at the adult stage. Moreover, M11003-3-1-15-8 had a superior numbers of florets. The novel disomic substitution line M11003-3-1-15-8, could be exploited as an important genetic material in wheat resistance breeding programs and genetic resources.

Global lipidomics profiling of cotton seed oil genotypes using CO2-based chromatography coupled to mass spectrometry

Refined cottonseed oil enjoys widespread applications in the food and chemical industries. Although the major lipids comprising cottonseed oil are well known, there are many diverse lipid species in cotton seeds that occur at much lower levels and have important nutritional or anti-nutritional properties. Lipidomics analysis of complex lipids in seed oil extracts using a single chromatographic technique is challenging due to the diversity of lipid polarity and the large range of concentrations of lipid species in biological samples. Ultra Performance Convergence Chromatography (UPC2) is a chromatographic system that utilizes liquid CO2 as primary solvent and co-solvents such as methanol as a mobile phase to leverage the chromatographic principles and selectivity of normal phase chromatography while providing the ease-of-use of reversed-phase LC. We have used UPC2 coupled to mass spectrometry for the separation of free fatty acids, neutral and polar lipids in a single cotton seed lipid extract. Several seed oil genotypes, including high oleic acid line of Gossypium hirsutum cv. Coker 312 with a nonfunctional Brassica napus allele of delta-12 fatty acid desaturase (FAD2) and naturally occurring high oleic acid line of G. barbadense, were profiled to identify global consequences of modulating seed oil fatty acid composition. Potential markers that discriminate the different genotypes were identified and quantified.

Effects of Allelic Variation in Glutenin Subunits and Gliadins on Baking-Quality in Near-isogenic Lines of Common Wheat cv. Longmai 19

Two lines, L-19-613 and L-19-626, were produced from the common wheat cultivar Longmai 19 (L-19) by six consecutive backcrosses using biochemical marker-assisted selection. L-19 (Glu-D1a, Glu-A3c/Gli-A1?; Gli-A1? is a gene coding for unnamed gliadin) and L-19-613 (Glu-D1d, Glu-A3c/Gli-A1?) formed a set of near-isogenic lines (NILs) for HMW-GS, while L-19-613 and L-19-626 (Glu-D1d, Glu-A3e/Gli-A1m) constituted another set of NILs for the LMW-GS/gliadins. The three L-19 NILs were grown in the wheat breeding nursery in 2007 and 2008. The field experiments were designed using the three-column contrast arrangement method with four replicates. The three lines were ranked as follows for measurements of gluten strength, which was determined by the gluten index, Zeleny sedimentation, the stability and breakdown time of the farinogram, the maximum resistance and area of the extensogram, and the P andWvalues of the alveogram: L-19-613 > L-19-626 > L-19. The parameters listed above were significantly different between lines at the 0.05 or 0.01 level. The Glu-D1 and Glu-A3/Gli-A1 loci had additive effects on the gluten index, Zeleny sedimentation, stability, breakdown time, maximum resistance, area, P and W values. Although genetic variation at the Glu-A3/Gli-A1 locus had a great influence on wheat quality, the genetic difference between Glu-D1d and Glu-D1a at the Glu-D1 locus was much larger than that of Glu-A3c/Gli-A1? and Glu-A3e/Gli-A1m at the Glu-A3/Gli-A1 locus. Glu-D1d had negative effects on the extensibility and the L value compared with Glu-D1a. In contrast, Glu-A3c/Gli-A1? had a positive effect on these traits compared with Glu-A3e/Gli-A1m.

Hyperspectral phenotyping on the microscopic scale: towards automated characterization of plant-pathogen interactions.

BackgroundThe detection and characterization of resistance reactions of crop plants against fungal pathogens are essential to select resistant genotypes. In breeding practice phenotyping of plant genotypes is realized by time consuming and expensive visual rating. In this context hyperspectral imaging (HSI) is a promising non-invasive sensor technique in order to accelerate and to automate classical phenotyping methods.A hyperspectral microscope was established to determine spectral changes on the leaf and cellular level of barley (Hordeum vulgare) during resistance reactions against powdery mildew (Blumeria graminis f.sp. hordei, isolate K1). Experiments were conducted with near isogenic barley lines of cv. Ingrid, including the susceptible wild type (WT), mildew locus a 12 (Mla12 based resistance) and the resistant mildew locus o 3 (mlo3 based resistance), respectively. The reflection of inoculated and non-inoculated leaves was recorded daily with a hyperspectral linescanner in the visual (400 – 700 nm) and near infrared (700 – 1000 nm) range 3 to 14 days after inoculation.ResultsData analysis showed no significant differences in spectral signatures between non-inoculated genotypes. Barley leaves of the near-isogenic genotypes, inoculated with B. graminis f.sp. hordei differed in the spectral reflectance over time, respectively. The susceptible genotypes (WT, Mla12) showed an increase in reflectance in the visible range according to symptom development. However, the spectral signature of the resistant mlo-genotype did not show significant changes over the experimental period. In addition, a recent data driven approach for automated discovery of disease specific signatures, which is based on a new representation of the data using Simplex Volume Maximization (SiVM) was applied. The automated approach - evaluated in only a fraction of time revealed results similar to the time and labor intensive manually assessed hyperspectral signatures. The new representation determined by SiVM was also used to generate intuitive and easy to interpretable summaries, e.g. fingerprints or traces of hyperspectral dynamics of the different genotypes.ConclusionWith this HSI based and data driven phenotyping approach an evaluation of host-pathogen interactions over time and a discrimination of barley genotypes differing in susceptibility to powdery mildew is possible.

The role of thionins in rice defence against root pathogens.

Thionins are antimicrobial peptides that are involved in plant defence. Here, we present an in-depth analysis of the role of rice thionin genes in defence responses against two root pathogens: the root-knot nematode Meloidogyne graminicola and the oomycete Pythium graminicola. The expression of rice thionin genes was observed to be differentially regulated by defence-related hormones, whereas all analysed genes were consistently down-regulated in M. graminicola-induced galls, at least until 7 days post-inoculation (dpi). Transgenic lines of Oryza sativa cv. Nipponbare overproducing OsTHI7 revealed decreased susceptibility to M. graminicola infection and P. graminicola colonization. Taken together, these results demonstrate the role of rice thionin genes in defence against two of the most damaging root pathogens attacking rice.

Expression of coat protein gene of Cucumber mosaic virus (CMV-subgroup IA) Gladiolus isolate in Nicotiana tabacum

The coat protein (CP)-mediated resistance against Cucumber mosaic virus (CMV) subgroup IA was developed in transgenic lines of Nicotiana tabacum cv. Petit Havana using Agrobacterium tumefaciens-mediated transformation. Ten independently transformed lines have developed, four of which were tested for resistance against CMV using virus challenge inoculations. The transgenic lines exhibiting complete resistance remained healthy and symptomless in their life span and showed reduced or no virus accumulation in their systemic leaves after virus challenge inoculation. These transgenic lines also showed resistance against CMV strains which are not closely related to CMV-Gladiolus strains. This is the first report of CP-mediated transgenic resistance against a CMV subgroup IA member isolated from India showing resistance to all CMV strains occurring in the same vicinity.