Whole genome association mapping of plant height in winter wheat (Triticum aestivum L..

Directory of Open Access Journals (Sweden)

Christine D Zanke

Full Text Available The genetic architecture of plant height was investigated in a set of 358 recent European winter wheat varieties plus 14 spring wheat varieties based on field data in eight environments. Genotyping of diagnostic markers revealed the Rht-D1b mutant allele in 58% of the investigated varieties, while the Rht-B1b mutant was only present in 7% of the varieties. Rht-D1 was significantly associated with plant height by using a mixed linear model and employing a kinship matrix to correct for population stratification. Further genotyping data included 732 microsatellite markers, resulting in 770 loci, of which 635 markers were placed on the ITMI map plus a set of 7769 mapped SNP markers genotyped with the 90 k iSELECT chip. When Bonferroni correction was applied, a total of 153 significant marker-trait associations (MTAs were observed for plant height and the SSR markers (-log10 (P-value ≥ 4.82 and 280 (-log10 (P-value ≥ 5.89 for the SNPs. Linear regression between the most effective markers and the BLUEs for plant height indicated additive effects for the MTAs of different chromosomal regions. Analysis of syntenic regions in the rice genome revealed closely linked rice genes related to gibberellin acid (GA metabolism and perception, i.e. GA20 and GA2 oxidases orthologous to wheat chromosomes 1A, 2A, 3A, 3B, 5B, 5D and 7B, ent-kaurenoic acid oxidase orthologous to wheat chromosome 7A, ent-kaurene synthase on wheat chromosome 2B, as well as GA-receptors like DELLA genes orthologous to wheat chromosomes 4B, 4D and 7A and genes of the GID family orthologous to chromosomes 2B and 5B. The data indicated that besides the widely used GA-insensitive dwarfing genes Rht-B1 and Rht-D1 there is a wide spectrum of loci available that could be used for modulating plant height in variety development.

Multitemporal field-based plant height estimation using 3D point clouds generated from small unmanned aerial systems high-resolution imagery

Science.gov (United States)

Malambo, L.; Popescu, S. C.; Murray, S. C.; Putman, E.; Pugh, N. A.; Horne, D. W.; Richardson, G.; Sheridan, R.; Rooney, W. L.; Avant, R.; Vidrine, M.; McCutchen, B.; Baltensperger, D.; Bishop, M.

2018-02-01

Plant breeders and agronomists are increasingly interested in repeated plant height measurements over large experimental fields to study critical aspects of plant physiology, genetics and environmental conditions during plant growth. However, collecting such measurements using commonly used manual field measurements is inefficient. 3D point clouds generated from unmanned aerial systems (UAS) images using Structure from Motion (SfM) techniques offer a new option for efficiently deriving in-field crop height data. This study evaluated UAS/SfM for multitemporal 3D crop modelling and developed and assessed a methodology for estimating plant height data from point clouds generated using SfM. High-resolution images in visible spectrum were collected weekly across 12 dates from April (planting) to July (harvest) 2016 over 288 maize (Zea mays L.) and 460 sorghum (Sorghum bicolor L.) plots using a DJI Phantom 3 Professional UAS. The study compared SfM point clouds with terrestrial lidar (TLS) at two dates to evaluate the ability of SfM point clouds to accurately capture ground surfaces and crop canopies, both of which are critical for plant height estimation. Extended plant height comparisons were carried out between SfM plant height (the 90th, 95th, 99th percentiles and maximum height) per plot and field plant height measurements at six dates throughout the growing season to test the repeatability and consistency of SfM estimates. High correlations were observed between SfM and TLS data (R2 = 0.88-0.97, RMSE = 0.01-0.02 m and R2 = 0.60-0.77 RMSE = 0.12-0.16 m for the ground surface and canopy comparison, respectively). Extended height comparisons also showed strong correlations (R2 = 0.42-0.91, RMSE = 0.11-0.19 m for maize and R2 = 0.61-0.85, RMSE = 0.12-0.24 m for sorghum). In general, the 90th, 95th and 99th percentile height metrics had higher correlations to field measurements than the maximum metric though differences among them were not statistically significant. The

Binary co-generative plants with height temperature SOFC fuel cells

International Nuclear Information System (INIS)

Tashevski, D; Dimitrov, K.; Armenski, S.

2005-01-01

In this paper, a field of binary co-generative plants with height temperature SOFC fuel cells is presented. Special attention of application of height temperature SOFC fuel cells and binary co-generative units has been given. These units made triple electricity and heat. Principle of combination of fuel cells with binary cycles has been presented. A model and computer programme for calculation of BKPFC, has been created. By using the program, all the important characteristic-results are calculated: power, efficiency, emission, dimension and economic analysis. On base of results, conclusions and recommendations has been given. (Author)

Binary co-generative plants with height temperature SOFC fuel cells

International Nuclear Information System (INIS)

Tashevski, D; Dimitrov, K.; Armenski, S.

2006-01-01

In this paper, a field of binary co-generative plants with height temperature SOFC fuel cells is presented. Special attention of application of height temperature SOFC fuel cells and binary co-generative units has been given. These units made triple electricity and heat. Principle of combination of fuel cells with binary cycles has been presented. A model and computer programme for calculation of BKPFC, has been created. By using the program, all the important characteristic-results are calculated: power, efficiency, emission, dimension and economic analysis. On base of results, conclusions and recommendations has been given. (Author)

Metal resistance sequences and transgenic plants

Science.gov (United States)

Meagher, Richard Brian; Summers, Anne O.; Rugh, Clayton L.

1999-10-12

The present invention provides nucleic acid sequences encoding a metal ion resistance protein, which are expressible in plant cells. The metal resistance protein provides for the enzymatic reduction of metal ions including but not limited to divalent Cu, divalent mercury, trivalent gold, divalent cadmium, lead ions and monovalent silver ions. Transgenic plants which express these coding sequences exhibit increased resistance to metal ions in the environment as compared with plants which have not been so genetically modified. Transgenic plants with improved resistance to organometals including alkylmercury compounds, among others, are provided by the further inclusion of plant-expressible organometal lyase coding sequences, as specifically exemplified by the plant-expressible merB coding sequence. Furthermore, these transgenic plants which have been genetically modified to express the metal resistance coding sequences of the present invention can participate in the bioremediation of metal contamination via the enzymatic reduction of metal ions. Transgenic plants resistant to organometals can further mediate remediation of organic metal compounds, for example, alkylmetal compounds including but not limited to methyl mercury, methyl lead compounds, methyl cadmium and methyl arsenic compounds, in the environment by causing the freeing of mercuric or other metal ions and the reduction of the ionic mercury or other metal ions to the less toxic elemental mercury or other metals.

Molecular Mapping of Reduced Plant Height Gene Rht24 in Bread Wheat.

Science.gov (United States)

Tian, Xiuling; Wen, Weie; Xie, Li; Fu, Luping; Xu, Dengan; Fu, Chao; Wang, Desen; Chen, Xinmin; Xia, Xianchun; Chen, Quanjia; He, Zhonghu; Cao, Shuanghe

2017-01-01

Height is an important trait related to plant architecture and yield potential in bread wheat ( Triticum aestivum L.). We previously identified a major quantitative trait locus QPH.caas-6A flanked by simple sequence repeat markers Xbarc103 and Xwmc256 that reduced height by 8.0-10.4%. Here QPH.caas-6A , designated as Rht24 , was confirmed using recombinant inbred lines (RILs) derived from a Jingdong 8/Aikang 58 cross. The target sequences of Xbarc103 and Xwmc256 were used as queries to BLAST against International Wheat Genome Sequence Consortium database and hit a super scaffold of approximately 208 Mb. Based on gene annotation of the scaffold, three gene-specific markers were developed to genotype the RILs, and Rht24 was narrowed to a 1.85 cM interval between TaAP2 and TaFAR . In addition, three single nucleotide polymorphism (SNP) markers linked to Rht24 were identified from SNP chip-based screening in combination with bulked segregant analysis. The allelic efficacy of Rht24 was validated in 242 elite wheat varieties using TaAP2 and TaFAR markers. These showed a significant association between genotypes and plant height. Rht24 reduced plant height by an average of 6.0-7.9 cm across environments and were significantly associated with an increased TGW of 2.0-3.4 g. The findings indicate that Rht24 is a common dwarfing gene in wheat breeding, and TaAP2 and TaFAR can be used for marker-assisted selection.

In-Field High-Throughput Phenotyping of Cotton Plant Height Using LiDAR

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Shangpeng Sun

2017-04-01

Full Text Available A LiDAR-based high-throughput phenotyping (HTP system was developed for cotton plant phenotyping in the field. The HTP system consists of a 2D LiDAR and an RTK-GPS mounted on a high clearance tractor. The LiDAR scanned three rows of cotton plots simultaneously from the top and the RTK-GPS was used to provide the spatial coordinates of the point cloud during data collection. Configuration parameters of the system were optimized to ensure the best data quality. A height profile for each plot was extracted from the dense three dimensional point clouds; then the maximum height and height distribution of each plot were derived. In lab tests, single plants were scanned by LiDAR using 0.5° angular resolution and results showed an R2 value of 1.00 (RMSE = 3.46 mm in comparison to manual measurements. In field tests using the same angular resolution; the LiDAR-based HTP system achieved average R2 values of 0.98 (RMSE = 65 mm for cotton plot height estimation; compared to manual measurements. This HTP system is particularly useful for large field application because it provides highly accurate measurements; and the efficiency is greatly improved compared to similar studies using the side view scan.

Correlation between agronomic and stem borer resistant traits in ...

African Journals Online (AJOL)

GY had significant relationship with days to 50% pollen shed, (DTA) (rg = 0.49**), plant height (PH) (rg ... that either days to 50% pollen shed or plant height could be considered in selection for stem borer resistance. ... HOW TO USE AJOL.

Genetic and Physiological Characterization of Two Clusters of Quantitative Trait Loci Associated With Seed Dormancy and Plant Height in Rice

OpenAIRE

Ye, Heng; Beighley, Donn H.; Feng, Jiuhuan; Gu, Xing-You

2013-01-01

Seed dormancy and plant height have been well-studied in plant genetics, but their relatedness and shared regulatory mechanisms in natural variants remain unclear. The introgression of chromosomal segments from weedy into cultivated rice (Oryza sativa) prompted the detection of two clusters (qSD1-2/qPH1 and qSD7-2/qPH7) of quantitative trait loci both associated with seed dormancy and plant height. Together, these two clusters accounted for >96% of the variances for plant height and ~71% of t...

High-resolution analysis of a QTL for resistance to Stagonospora nodorum glume blotch in wheat reveals presence of two distinct resistance loci in the target interval.

Science.gov (United States)

Shatalina, Margarita; Messmer, Monika; Feuillet, Catherine; Mascher, Fabio; Paux, Etienne; Choulet, Frédéric; Wicker, Thomas; Keller, Beat

2014-03-01

Stagonospora nodorum glume blotch (SNG), caused by the necrotrophic fungus Stagonospora nodorum, is one of the economically important diseases of bread wheat (Triticum aestivum L.). Resistance to SNG is known to be quantitative and previous studies of a recombinant inbred line (RIL) population identified a major quantitative trait locus (QTL) for resistance to SNG on the short arm of chromosome 3B. To localize this QTL (QSng.sfr-3BS) with high resolution, we constructed a genetic map for the QTL target region using information from sequenced flow-sorted chromosomes 3B of the two parental cultivars 'Arina' and 'Forno', the physical map of chromosome 3B of cultivar 'Chinese Spring' and BAC-clone sequences. The mapping population of near-isogenic lines (NIL) was evaluated for SNG resistance in field infection tests. NILs segregated for disease resistance as well as for plant height; additionally, we observed a high environmental influence on the trait. Our analysis detected a strong negative correlation of SNG resistance and plant height. Further analysis of the target region identified two linked loci associated with SNG resistance. One of them was also associated with plant height, revealing an effect of QSng.sfr-3BS on plant height that was hidden in the RIL population. This result demonstrates an unexpectedly high genetic complexity of resistance controlled by QSng.sfr-3BS and shows the importance of the study of QTL in mendelized form in NILs.

Recessive Resistance to Plant Viruses: Potential Resistance Genes Beyond Translation Initiation Factors

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Masayoshi Hashimoto

2016-10-01

Full Text Available The ability of plant viruses to propagate their genomes in host cells depends on many host factors. In the absence of an agrochemical that specifically targets plant viral infection cycles, one of the most effective methods for controlling viral diseases in plants is taking advantage of the host plant’s resistance machinery. Recessive resistance is conferred by a recessive gene mutation that encodes a host factor critical for viral infection. It is a branch of the resistance machinery and, as an inherited characteristic, is very durable. Moreover, recessive resistance may be acquired by a deficiency in a negative regulator of plant defense responses, possibly due to the autoactivation of defense signaling. Eukaryotic translation initiation factor (eIF 4E and eIF4G and their isoforms are the most widely exploited recessive resistance genes in several crop species, and they are effective against a subset of viral species. However, the establishment of efficient, recessive resistance-type antiviral control strategies against a wider range of plant viral diseases requires genetic resources other than eIF4Es. In this review, we focus on recent advances related to antiviral recessive resistance genes evaluated in model plants and several crop species. We also address the roles of next-generation sequencing and genome editing technologies in improving plant genetic resources for recessive resistance-based antiviral breeding in various crop species.

Effect of fiber post length and abutment height on fracture resistance of endodontically treated premolars prepared for zirconia crowns.

Science.gov (United States)

Lin, Jie; Matinlinna, Jukka Pekka; Shinya, Akikazu; Botelho, Michael George; Zheng, Zhiqiang

2018-04-01

The purpose of this study was to compare the fracture resistance, mode of fracture, and stress distribution of endodontically treated teeth prepared with three different fiber post lengths and two different abutment heights, using both experimental and finite element (FE) approaches. Forty-eight human maxillary premolars with two roots were selected and endodontically treated. The teeth were randomly distributed into six equally sized groups (n = 8) with different combinations of post lengths (7.5, 11, and 15 mm) and abutment heights (3 and 5 mm). All the teeth restored with glass fiber post (Rely X Fiber Post, 3M ESPE, USA) and a full zirconia crown. All the specimens were thermocycled and then loaded to failure at an oblique angle of 135°. Statistical analysis was performed for the effects of post length and abutment height on failure loads using ANOVA and Tukey's honestly significant difference test. In addition, corresponding FE models of a premolar restored with a glass fiber post were developed to examine mechanical responses. The factor of post length (P abutment height (P > 0.05) did not have a significant effect on failure load. The highest mean fracture resistance was recorded for the 15 mm post length and 5 mm abutment height test group, which was significantly more resistant to fracture than the 7.5 mm post and 5 mm abutment height group (P abutment heights.

Resistance mechanisms to plant viruses: an overview

NARCIS (Netherlands)

Goldbach, R.W.; Bucher, E.C.; Prins, A.H.

2003-01-01

To obtain virus-resistant host plants, a range of operational strategies can be followed nowadays. While for decades plant breeders have been able to introduce natural resistance genes in susceptible genotypes without knowing precisely what these resistance traits were, currently a growing number of

Genetic analysis of plant height in induced mutants of aromatic rice

International Nuclear Information System (INIS)

Kole, P.C.

2005-01-01

Inheritance of plant height in five gamma-ray induced mutants of aromatic rice cultivar Gobindabhog was studied through 6 x 6 diallel cross and segregation analyses. Diallel analysis revealed presence of additive and non-additive gene action with the preponderance of the latter. Proportion of dominant and recessive alleles was distributed unequally among the parents. The direction of dominance was towards tallness. The number of groups of genes was found to be three. The segregation analysis indicated the role of a single major recessive gene for height reduction in three mutants and, in another mutant, a single major recessive gene with negative modifiers. The other semi-dwarf mutant had two major recessive genes with almost equal effect in height reduction. The mutant allele(s) of the latter two mutants were non-allelic to sd sub(1) gene, which could be used as an alternative source of Dee Gee Woo Gen to widen the genetic diversity in semi-dwarfism [it

Linking aboveground and belowground inducible plant resistance

NARCIS (Netherlands)

Bezemer, T.M.

2009-01-01

Induced resistance of plants against pests and diseases via plant defense responses is well documented and can occur aboveground, in the leaves, and belowground in the roots. A number of recent studies have shown that soil-borne pests can also induce plant resistance aboveground and vice versa.

Plant Translation Factors and Virus Resistance

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Hélène Sanfaçon

2015-06-01

Full Text Available Plant viruses recruit cellular translation factors not only to translate their viral RNAs but also to regulate their replication and potentiate their local and systemic movement. Because of the virus dependence on cellular translation factors, it is perhaps not surprising that many natural plant recessive resistance genes have been mapped to mutations of translation initiation factors eIF4E and eIF4G or their isoforms, eIFiso4E and eIFiso4G. The partial functional redundancy of these isoforms allows specific mutation or knock-down of one isoform to provide virus resistance without hindering the general health of the plant. New possible targets for antiviral strategies have also been identified following the characterization of other plant translation factors (eIF4A-like helicases, eIF3, eEF1A and eEF1B that specifically interact with viral RNAs and proteins and regulate various aspects of the infection cycle. Emerging evidence that translation repression operates as an alternative antiviral RNA silencing mechanism is also discussed. Understanding the mechanisms that control the development of natural viral resistance and the emergence of virulent isolates in response to these plant defense responses will provide the basis for the selection of new sources of resistance and for the intelligent design of engineered resistance that is broad-spectrum and durable.

Editing plants for virus resistance using CRISPR-Cas.

Science.gov (United States)

Green, J C; Hu, J S

This minireview summarizes recent advancements using the clustered regularly interspaced palindromic repeats-associated nuclease systems (CRISPR-Cas) derived from prokaryotes to breed plants resistant to DNA and RNA viruses. The CRISPR-Cas system represents a powerful tool able to edit and insert novel traits into plants precisely at chosen loci offering enormous advantages to classical breeding. Approaches to engineering plant virus resistance in both transgenic and non-transgenic plants are discussed. Iterations of the CRISPR-Cas system, FnCas9 and C2c2 capable of editing RNA in eukaryotic cells offer a particular advantage for providing resistance to RNA viruses which represent the great majority of known plant viruses. Scientists have obtained conflicting results using gene silencing technology to produce transgenic plants resistant to geminiviruses. CRISPR-Cas systems engineered in plants to target geminiviruses have consistently reduced virus accumulation providing increased resistance to virus infection. CRISPR-Cas may provide novel and reliable approaches to control geminiviruses and other ssDNA viruses such as Banana bunchy top virus (BBTV).

Plant height and grain yield of soybean depending on the year, irrigation and variety

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Daria Galić Šubašić

2017-01-01

Full Text Available Three-year field trials determined the influence of the year, irrigation treatment and varieties on plant height and grain yield of soybeans in the eastern Croatia conditions. All three investigated factors, as well as their interactions, with the exception of irrigation interactions and varieties that were significant at P=0.05, show a statistically significant influence (P=0.01 on the height of soybean plants. Soybean grain yields, as well as all their interactions, affect the significance level P=0.01. The obtained values of soybean grain yields during the study (mostly greater than 3000 kg ha-1 indicate the importance of selecting appropriate varieties and irrigation treatment in adapting soybean production to adverse weather effects of the year.

Plant age, communication, and resistance to herbivores: young sagebrush plants are better emitters and receivers.

Science.gov (United States)

Shiojiri, Kaori; Karban, Richard

2006-08-01

Plants progress through a series of distinct stages during development, although the role of plant ontogeny in their defenses against herbivores is poorly understood. Recent work indicates that many plants activate systemic induced resistance after herbivore attack, although the relationship between resistance and ontogeny has not been a focus of this work. In addition, for sagebrush and a few other species, individuals near neighbors that experience simulated herbivory become more resistant to subsequent attack. Volatile, airborne cues are required for both systemic induced resistance among branches and for communication among individuals. We conducted experiments in stands of sagebrush of mixed ages to determine effects of plant age on volatile signaling between branches and individuals. Young and old control plants did not differ in levels of chewing damage that they experienced. Systemic induced resistance among branches was only observed for young plants. Young plants showed strong evidence of systemic resistance only if airflow was permitted among branches; plants with only vascular connections showed no systemic resistance. We also found evidence for volatile communication between individuals. For airborne communication, young plants were more effective emitters of cues as well as more responsive receivers of volatile cues.

Transgenic Strategies for Enhancement of Nematode Resistance in Plants

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Muhammad A. Ali

2017-05-01

Full Text Available Plant parasitic nematodes (PPNs are obligate biotrophic parasites causing serious damage and reduction in crop yields. Several economically important genera parasitize various crop plants. The root-knot, root lesion, and cyst nematodes are the three most economically damaging genera of PPNs on crops within the family Heteroderidae. It is very important to devise various management strategies against PPNs in economically important crop plants. Genetic engineering has proven a promising tool for the development of biotic and abiotic stress tolerance in crop plants. Additionally, the genetic engineering leading to transgenic plants harboring nematode resistance genes has demonstrated its significance in the field of plant nematology. Here, we have discussed the use of genetic engineering for the development of nematode resistance in plants. This review article also provides a detailed account of transgenic strategies for the resistance against PPNs. The strategies include natural resistance genes, cloning of proteinase inhibitor coding genes, anti-nematodal proteins and use of RNA interference to suppress nematode effectors. Furthermore, the manipulation of expression levels of genes induced and suppressed by nematodes has also been suggested as an innovative approach for inducing nematode resistance in plants. The information in this article will provide an array of possibilities to engineer resistance against PPNs in different crop plants.

Induced lodging resistance in upland rice

International Nuclear Information System (INIS)

Arumugam Pillai, M.; Subramanian, M.

1990-01-01

Full text: Seeds of two short duration but tall upland rice varieties ''PMK 1'' and ''Poongar'', susceptible to lodging, were subjected to mutation breeding in 1988-1989. Dry seeds of these two varieties were treated with 20, 25 and 30 krad of gamma rays and soaked seeds were treated with 40, 50 and 60 mM concentration of EMS. In M 2 generation lodging was measured and a correlation study was made between the angle of lodging and various characters like plant height, length of lower internode, productive tiller number, culm diameter and panicle weight. The angle to which the main tiller can be bent before lodging on the 25th day after flowering was measured by using a protractor. Those plants which lodged at an angle beyond 30 deg. from the vertical plane were classified as lodging. From 60,000 M 2 plants, 78 lodging resistant semi-dwarf mutants and 5 dwarf mutants were selected. As expected, there was generally a negative correlation between internode length and lodging resistance and a positive correlation of culm diameter with lodging resistance. For plant height and tiller numbers, correlations were not so clear. (author)

Vitamins for enhancing plant resistance.

Science.gov (United States)

Boubakri, Hatem; Gargouri, Mahmoud; Mliki, Ahmed; Brini, Faiçal; Chong, Julie; Jbara, Moez

2016-09-01

This paper provides an overview on vitamins with inducing activities in plants, the molecular and cellular mechanisms implicated, and the hormonal signalling-network regulating this process. Moreover, it reports how vitamins might be part of the molecular events linked to induced resistance by the conventional elicitors. Induced resistance (IR), exploiting the plant innate-defense system is a sustainable strategy for plant disease control. In the last decade, vitamins have been proven to act as inducers of disease resistance, and these findings have received an important attention owing to their safety and cost effectiveness. Vitamins, including thiamine (TH, vitamin B1), riboflavin (RF, vitamin B2), menadione sodium bisulfite (MSB, vitamin K3), Para-aminobenzoic acid (PABA, vitamin Bx), and folic acid (FA, vitamin B9) provided an efficient protection against a wide range of pathogens through the modulation of specific host-defense facets. However, other vitamins, such as ascorbic acid (AA, vitamin C) and tocopherols (vitamin E), have been shown to be a part of the molecular mechanisms associated to IR. The present review is the first to summarize what vitamins are acting as inducers of disease resistance in plants and how could they be modulated by the conventional elicitors. Thus, this report provides an overview on the protective abilities of vitamins and the molecular and cellular mechanisms underlying their activities. Moreover, it describes the hormonal-signalling network regulating vitamin-signal transduction during IR. Finally, a biochemical model describing how vitamins are involved in the establishment of IR process is discussed.

Phosphorylation and proteome dynamics in pathogen-resistant tomato plants

OpenAIRE

Stulemeijer, I.J.E.

2008-01-01

Microbial plant pathogens impose a continuous threat on global food production. Similar to disease resistance in mammals, an innate immune system allows plants to recognise pathogens and swiftly activate defence. For the work described in this thesis, the interaction between tomato and the extracellular fungal pathogen Cladosporium fulvum serves as a model system to study host resistance and susceptibility in plant-pathogen interactions. Resistance to C. fulvum in tomato plants follows the ge...

Reevaluating the conceptual framework for applied research on host-plant resistance.

Science.gov (United States)

Stout, Michael J

2013-06-01

Applied research on host-plant resistance to arthropod pests has been guided over the past 60 years by a framework originally developed by Reginald Painter in his 1951 book, Insect Resistance in Crop Plants. Painter divided the "phenomena" of resistance into three "mechanisms," nonpreference (later renamed antixenosis), antibiosis, and tolerance. The weaknesses of this framework are discussed. In particular, this trichotomous framework does not encompass all known mechanisms of resistance, and the antixenosis and antibiosis categories are ambiguous and inseparable in practice. These features have perhaps led to a simplistic approach to understanding arthropod resistance in crop plants. A dichotomous scheme is proposed as a replacement, with a major division between resistance (plant traits that limit injury to the plant) and tolerance (plant traits that reduce amount of yield loss per unit injury), and the resistance category subdivided into constitutive/inducible and direct/indirect subcategories. The most important benefits of adopting this dichotomous scheme are to more closely align the basic and applied literatures on plant resistance and to encourage a more mechanistic approach to studying plant resistance in crop plants. A more mechanistic approach will be needed to develop novel approaches for integrating plant resistance into pest management programs. © 2012 Institute of Zoology, Chinese Academy of Sciences.

Frost resistance in alpine woody plants.

Science.gov (United States)

Neuner, Gilbert

2014-01-01

This report provides a brief review of key findings related to frost resistance in alpine woody plant species, summarizes data on their frost resistance, highlights the importance of freeze avoidance mechanisms, and indicates areas of future research. Freezing temperatures are possible throughout the whole growing period in the alpine life zone. Frost severity, comprised of both intensity and duration, becomes greater with increasing elevation and, there is also a greater probability, that small statured woody plants, may be insulated by snow cover. Several frost survival mechanisms have evolved in woody alpine plants in response to these environmental conditions. Examples of tolerance to extracellular freezing and freeze dehydration, life cycles that allow species to escape frost, and freeze avoidance mechanisms can all be found. Despite their specific adaption to the alpine environment, frost damage can occur in spring, while all alpine woody plants have a low risk of frost damage in winter. Experimental evidence indicates that premature deacclimation in Pinus cembra in the spring, and a limited ability of many species of alpine woody shrubs to rapidly reacclimate when they lose snow cover, resulting in reduced levels of frost resistance in the spring, may be particularly critical under the projected changes in climate. In this review, frost resistance and specific frost survival mechanisms of different organs (leaves, stems, vegetative and reproductive over-wintering buds, flowers, and fruits) and tissues are compared. The seasonal dynamics of frost resistance of leaves of trees, as opposed to woody shrubs, is also discussed. The ability of some tissues and organs to avoid freezing by supercooling, as visualized by high resolution infrared thermography, are also provided. Collectively, the report provides a review of the complex and diverse ways that woody plants survive in the frost dominated environment of the alpine life zone.

Frost resistance of alpine woody plants

Directory of Open Access Journals (Sweden)

Gilbert eNeuner

2014-12-01

Full Text Available This report provides a brief review of key findings related to frost resistance in alpine woody plant species, summarizes data on their frost resistance, highlights the importance of freeze avoidance mechanisms, and indicates areas of future research.Freezing temperatures are possible throughout the whole growing period in the alpine life zone. Frost severity, comprised of both intensity and duration, becomes greater with increasing elevation and, there is also a greater probability, that small statured woody plants, may be insulated by snow cover.Several frost survival mechanisms have evolved in woody alpine plants in response to these environmental conditions. Examples of tolerance to extracellular freezing and freeze dehydration, life cycles that allow species to escape frost, and freeze avoidance mechanisms can all be found. Despite their specific adaption to the alpine environment, frost damage can occur in spring, while all alpine woody plants have a low risk of frost damage in winter. Experimental evidence indicates that premature deacclimation in Pinus cembra in the spring, and a limited ability of many species of alpine woody shrubs to rapidly reacclimate when they lose snow cover, resulting in reduced levels of frost resistance in the spring, may be particularly critical under the projected changes in climate.In this review, frost resistance and specific frost survival mechanisms of different organs (leaves, stems, vegetative and reproductive over-wintering buds, flowers and fruits and tissues are compared. The seasonal dynamics of frost resistance of leaves of trees, as opposed to woody shrubs, is also discussed. The ability of some tissues and organs to avoid freezing by supercooling, as visualized by high resolution infrared thermography, are also provided. Collectively, the report provides a review of the complex and diverse ways that woody plants survive in the frost dominated environment of the alpine life zone.

Effects of Sludge Compost on EC value of Saline Soil and Plant Height of Medicago

Science.gov (United States)

Sun, Chongyang; Zhao, Ke; Chen, Xing; Wang, Xiaohui

2017-12-01

In this study, the effects of sludge composting on the EC value of saline soil and the response to Medicago plant height were studied by planting Medicago with pots for 45 days in different proportions as sludge composting with saline soil. The results showed that the EC value of saline soil did not change obviously with the increase of fertilization ratio,which indicated that the EC value of saline soil was close to that of the original soil. The EC decreased by 31.45% at fertilization ratio of 40%. The height of Medicago reached the highest at 40% fertilization ratio, and that was close to 60% fertilization ratio, and the difference was significant with other treatments. By comprehensive analyse and compare,the optimum application rate of sludge compost was 40% under this test condition.

Inheritance and identification of a major quantitative trait locus (QTL) that confers resistance to Meloidogyne incognita and a novel QTL for plant height in sweet sorghum

Science.gov (United States)

Southern root-knot nematodes (Meloidogyne incognita) are a pest on many economically important row crop and vegetable species and management relies on chemicals, plant resistance, and cultural practices such as crop rotation. Little is known about the inheritance of resistance to M. incognita or the...

Genetic study on heading time and plant height of wheat irradiated by 137Cs and 60Co γ-rays

International Nuclear Information System (INIS)

Wang Guixue; Zhu Xiaoda

1995-01-01

The 137 Cs and 60 Co γ-rays with 0, 20, 30 and 40 krad were used to irradiate two wheat varieties to study the genetic effects of both irradiation sources on heading time and plant height. It revealed that both irradiation sources had similar impact on heading time and plant height and the effects were significant. It was clear that both irradiation sources were able to induce the generation of early ripening and short-stalked mutants. With regard to the heading time and plant height, the means and genetic parameters, e.g., genetic variance, genetic coefficient of variation, heritability, genetic advance and relative genetic advance, varied with varieties, irradiation dosages and generations. Mutants with good characters were obtained by using variety 77-zhong-2882 and an irradiation dose of 30 krad. The genetic effects of irradiation were remarkable in their M 2 and M 3 generations

The Lr34 adult plant rust resistance gene provides seedling resistance in durum wheat without senescence.

Science.gov (United States)

Rinaldo, Amy; Gilbert, Brian; Boni, Rainer; Krattinger, Simon G; Singh, Davinder; Park, Robert F; Lagudah, Evans; Ayliffe, Michael

2017-07-01

The hexaploid wheat (Triticum aestivum) adult plant resistance gene, Lr34/Yr18/Sr57/Pm38/Ltn1, provides broad-spectrum resistance to wheat leaf rust (Lr34), stripe rust (Yr18), stem rust (Sr57) and powdery mildew (Pm38) pathogens, and has remained effective in wheat crops for many decades. The partial resistance provided by this gene is only apparent in adult plants and not effective in field-grown seedlings. Lr34 also causes leaf tip necrosis (Ltn1) in mature adult plant leaves when grown under field conditions. This D genome-encoded bread wheat gene was transferred to tetraploid durum wheat (T. turgidum) cultivar Stewart by transformation. Transgenic durum lines were produced with elevated gene expression levels when compared with the endogenous hexaploid gene. Unlike nontransgenic hexaploid and durum control lines, these transgenic plants showed robust seedling resistance to pathogens causing wheat leaf rust, stripe rust and powdery mildew disease. The effectiveness of seedling resistance against each pathogen correlated with the level of transgene expression. No evidence of accelerated leaf necrosis or up-regulation of senescence gene markers was apparent in these seedlings, suggesting senescence is not required for Lr34 resistance, although leaf tip necrosis occurred in mature plant flag leaves. Several abiotic stress-response genes were up-regulated in these seedlings in the absence of rust infection as previously observed in adult plant flag leaves of hexaploid wheat. Increasing day length significantly increased Lr34 seedling resistance. These data demonstrate that expression of a highly durable, broad-spectrum adult plant resistance gene can be modified to provide seedling resistance in durum wheat. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Plant height revertants of Dominant Semidwarf mutant rice created by low-energy ion irradiation

Energy Technology Data Exchange (ETDEWEB)

Liu Binmei [Key Laboratory of Ion Beam Bioengineering, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Wu Yuejin [Key Laboratory of Ion Beam Bioengineering, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)], E-mail: yjwu@ipp.ac.cn; Xu Xue; Song, M.; Zhao, M. [Key Laboratory of Ion Beam Bioengineering, Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Fu, X.D. [Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101 (China)

2008-04-15

Dominant Semidwarf mutant rice (Sdd) was obtained from its wild type (WT) by irradiation with a low-energy ion beam. Six tall revertants of Sdd were induced by irradiation. The revertants restored the plant height to that of WT plants. Investigation of the agronomic character and genetic analysis indicate that the revertants are similar to WT plants with putative different inherited mutations. The revertants were checked for DNA differences using the simple sequence repeat technique. Among 408 such primers used, only 2 primers detected mutation sites in the revertants, which provided the molecular evidence for the revertants induced from Sdd. This study indicates that ion irradiation may be used as a mutagen to create revertants for plant architecture studies and could be a new application.

Engineering resistance to plant viruses: Present status and future prospects

Science.gov (United States)

Plant viruses cause severe crop losses across the globe. Resistant cultivars together with pesticide application are commonly used to avoid the losses caused by plant viruses. However, very limited success has been achieved at diminishing the impact of plant viruses. Use of virus resistant plant is ...

Plant-Derived Antimicrobials: Insights into Mitigation of Antimicrobial Resistance

Directory of Open Access Journals (Sweden)

Shun-Kai Yang

2018-07-01

Full Text Available Antibiotic resistance had first been reported not long after the discovery of the first antibiotic and has remained a major public health issue ever since. Challenges are constantly encountered during the mitigation process of antibiotic resistance in the clinical setting; especially with the emergence of the formidable superbug, a bacteria with multiple resistance towards different antibiotics; this resulted in the term multidrug resistant (MDR bacteria. This rapid evolution of the resistance phenomenon has propelled researchers to continuously uncover new antimicrobial agents in a bid to hopefully, downplay the rate of evolution despite a drying pipeline. Recently, there has been a paradigm shift in the mining of potential antimicrobials; in the past, targets for drug discovery were from microorganisms and at current, the focus has moved onto plants, this is mainly due to the beneficial attributes that plants are able to confer over that of microorganisms. This review will briefly discuss antibiotic resistance mechanisms employed by resistant bacteria followed by a detailed expository regarding the use of secondary metabolites from plants as a potential solution to the MDR pathogen. Finally, future prospects recommending enhancements to the usage of plant secondary metabolites to directly target antibiotic resistant pathogens will be discussed.

Multiple-height microstructure fabricated by deep reactive ion etching and soft resist masks combined with UV curing

International Nuclear Information System (INIS)

Sato, R; Sawada, T; Kumagai, S; Sasaki, M

2014-01-01

Multiple-height microstructures are realized by deep reactive ion etching and UV-cured photoresist used in the embedded mask process. Although the UV-cured photoresist is a soft mask, its material property becomes stable against resist thinner and UV exposure. A layered resist pattern can be realized by stacking normal photoresist on the UV-cured photoresist. The normal photoresist can be selectively removed by the flush exposure and developing after the first Si etching. This technique is applied to two MEMS devices

Enhanced disease resistance and drought tolerance in transgenic rice plants overexpressing protein elicitors from Magnaporthe oryzae.

Science.gov (United States)

Wang, Zhenzhen; Han, Qiang; Zi, Qian; Lv, Shun; Qiu, Dewen; Zeng, Hongmei

2017-01-01

Exogenous application of the protein elicitors MoHrip1 and MoHrip2, which were isolated from the pathogenic fungus Magnaporthe oryzae (M. oryzae), was previously shown to induce a hypersensitive response in tobacco and to enhance resistance to rice blast. In this work, we successfully transformed rice with the mohrip1 and mohrip2 genes separately. The MoHrip1 and MoHrip2 transgenic rice plants displayed higher resistance to rice blast and stronger tolerance to drought stress than wild-type (WT) rice and the vector-control pCXUN rice. The expression of salicylic acid (SA)- and abscisic acid (ABA)-related genes was also increased, suggesting that these two elicitors may trigger SA signaling to protect the rice from damage during pathogen infection and regulate the ABA content to increase drought tolerance in transgenic rice. Trypan blue staining indicated that expressing MoHrip1 and MoHrip2 in rice plants inhibited hyphal growth of the rice blast fungus. Relative water content (RWC), water usage efficiency (WUE) and water loss rate (WLR) were measured to confirm the high capacity for water retention in transgenic rice. The MoHrip1 and MoHrip2 transgenic rice also exhibited enhanced agronomic traits such as increased plant height and tiller number.

Avaliação e seleção de progênies F3 de cafeeiros de porte baixo com o gene SH3 de resistência a Hemileia vastatrix Berk. et Br. Evaluation and selection of Coffea arabica F3 progenies with low height and the leaf-rust SH3 resistence gene

Directory of Open Access Journals (Sweden)

Albano Silva da Conceição

2005-01-01

porte baixo portando o gene SH3 de resistência ao agente da ferrugem.The present work evaluated 36 arabic coffee (Coffea arabica L. F3 progenies, originated from crosses among cultivars Catuaí Vermelho IAC 46 and Catuaí Vermelho IAC 81 and access IAC 1110 (BA-10. This last cultivar came from India and exhibits SH2 and SH3 rust resistance genes. The experiment was installed in 1988 at the Experimental Center of the Agronomic Institute (IAC/APTA, in Campinas, using random blocks design with six repetitions and two plants per plot. Field evaluations included yield (average of seven annual harvests, vegetative vigor, resistance to leaf rust, plant size, color of young leaves and complete fruit maturation period. Based on these evaluations, plants exhibiting high yield, good vegetative vigor, low height, and resistance to the leaf rust agent Hemileia vastatrix were selected. Fruit yield of selected plants was calculated and seeds were characterized according to type (flat, peaberry and elephant, outturn and grain size. A total of 11 optimal F3 progenies were identified as rust resistant. By further classifications, 39 plants out from these progenies were selected, along with 15 plants from other 25 evaluated progenies. Laboratory analyses lead to a final selection of 18 coffee trees, all exhibiting leaf rust resistance, high yield and low height. Also, F4 progenies of selected plants had been evaluated regarding height and leaf rust resistance, at seedling stage, in greenhouse conditions. Eighteen plants were selected for further analysis and move forward from F3 to F4 generation in the coffee breeding program developed by IAC.

DELLA genes restrict inflorescence meristem function independently of plant height.

Science.gov (United States)

Serrano-Mislata, Antonio; Bencivenga, Stefano; Bush, Max; Schiessl, Katharina; Boden, Scott; Sablowski, Robert

2017-09-01

DELLA proteins associate with transcription factors to control plant growth in response to gibberellin 1 . Semi-dwarf DELLA mutants with improved harvest index and decreased lodging greatly improved global food security during the 'green revolution' in the 1960-1970s 2 . However, DELLA mutants are pleiotropic and the developmental basis for their effects on plant architecture remains poorly understood. Here, we show that DELLA proteins have genetically separable roles in controlling stem growth and the size of the inflorescence meristem, where flowers initiate. Quantitative three-dimensional image analysis, combined with a genome-wide screen for DELLA-bound loci in the inflorescence tip, revealed that DELLAs limit meristem size in Arabidopsis by directly upregulating the cell-cycle inhibitor KRP2 in the underlying rib meristem, without affecting the canonical WUSCHEL-CLAVATA meristem size regulators 3 . Mutation of KRP2 in a DELLA semi-dwarf background restored meristem size, but not stem growth, and accelerated flower production. In barley, secondary mutations in the DELLA gain-of-function mutant Sln1d 4 also uncoupled meristem and inflorescence size from plant height. Our work reveals an unexpected and conserved role for DELLA genes in controlling shoot meristem function and suggests how dissection of pleiotropic DELLA functions could unlock further yield gains in semi-dwarf mutants.

Stem nematode counteracts plant resistance of aphids in alfalfa, Medicago sativa.

Science.gov (United States)

Ramirez, Ricardo A; Spears, Lori R

2014-10-01

Plants are exploited by a diverse community of insect herbivores and phytopathogens that interact indirectly through plant-mediated interactions. Generally, plants are thought to respond to insects and pathogens through different defensive signaling pathways. As plants are selected for resistance to one phytophagous organism type (insect vs. pathogen) in managed systems, it is not clear how this selection may affect community interactions. This study examined the effect of nematode-resistant varieties on aphid (Acyrthosiphon pisum) suppression, and then determined how infection by the stem nematode, Ditylenchus dipsaci, mediated ecological effects on aphids and on plant defense proteins. Four alfalfa (Medicago sativa) varieties were selected with resistance to nematodes only (+,-), aphids only (-,+), nematodes and aphids (+,+), and susceptibility to nematodes and aphids (-,-). Field and greenhouse experiments were conducted to isolate the effect of nematode infection and aphid abundance on each variety. We found that varieties resistant to nematode, regardless of aphid resistance, had the lowest aphid counts, suggesting possible cross-resistance. Aphid abundance, however, increased when plants were exposed to nematodes. Resistant varieties were associated with elevated saponins but these compounds were not affected by insect or pathogen feeding. Concentrations of peroxidases and trypsin inhibitors, however, were increased in nematode resistant varieties when exposed to nematodes and aphids, respectively. The patterns of plant defense were variable, and a combination of resistance traits and changes in nutrient availability may drive positive interactions between nematodes and aphids aboveground.

Role of the plant cell wall in gravity resistance.

Science.gov (United States)

Hoson, Takayuki; Wakabayashi, Kazuyuki

2015-04-01

Gravity resistance, mechanical resistance to the gravitational force, is a principal graviresponse in plants, comparable to gravitropism. The cell wall is responsible for the final step of gravity resistance. The gravity signal increases the rigidity of the cell wall via the accumulation of its constituents, polymerization of certain matrix polysaccharides due to the suppression of breakdown, stimulation of cross-link formation, and modifications to the wall environment, in a wide range of situations from microgravity in space to hypergravity. Plants thus develop a tough body to resist the gravitational force via an increase in cell wall rigidity and the modification of growth anisotropy. The development of gravity resistance mechanisms has played an important role in the acquisition of responses to various mechanical stresses and the evolution of land plants. Copyright © 2014 Elsevier Ltd. All rights reserved.

Within plant resistance to water flow in tomato and sweet melons ...

African Journals Online (AJOL)

Efficient water resource management in relation to water use and crop yields is premised on the knowledge of plant resistance to water flow. However, such studies are limited and for most crops, the within plant resistance to water flow remains largely unknown. In this study, within plant resistance to water transport ...

In vitro fracture resistance of endodontically treated central incisors with varying ferrule heights and configurations.

Science.gov (United States)

Tan, Philip L B; Aquilino, Steven A; Gratton, David G; Stanford, Clark M; Tan, Swee Chian; Johnson, William T; Dawson, Deborah

2005-04-01

The in vitro effectiveness of a uniform circumferential ferrule has been established in the literature; however, the effect of a nonuniform circumferential ferrule height on fracture resistance is unknown. This in vitro study investigated the resistance to static loading of endodontically treated teeth with uniform and nonuniform ferrule configurations. Fifty extracted intact maxillary human central incisors were randomly assigned to 1 of 5 groups: CRN, no root canal treatment (RCT), restored with a crown; RCT/CRN, no dowel/core, restored with a crown; 2 FRL, 2-mm ferrule, cast dowel/core and crown; 0.5/2 FRL, nonuniform ferrule (2 mm buccal and lingual, 0.5 mm proximal), cast dowel/core and crown; and 0 FRL, no ferrule, cast dowel/core and crown. The teeth were prepared to standardized specifications and stored for 72 hours in 100% humidity prior to testing. Testing was conducted with a universal testing machine with the application of a static load, and the load (N) at failure was recorded. Statistical analysis was performed with a 1-way analysis of variance and the Tukey Honestly Significant Difference test (alpha=.05). The mode of fracture was noted by visual inspection for all specimens. There was strong evidence of group differences in mean fracture strength ( P <.0001). Following adjustment for all pairwise group comparisons, it was found that the lack of a ferrule resulted in a significantly lower mean fracture strength (0 FRL: 264.93 +/- 78.33 N) relative to all other groups. The presence of a nonuniform (0.5 to 2-mm vertical height) ferrule (0.5/2 FRL: 426.64 +/- 88.33 N) resulted in a significant decrease ( P =.0001) in mean fracture strength when compared with the uniform 2-mm vertical ferrule (2 FRL: 587.23 +/- 110.25 N), the group without RCT (CRN: 583.67 +/- 86.09 N), and the RCT-treated tooth with a crown alone (CRN/RCT: 571.04 +/- 154.86 N). The predominant mode of failure was an oblique fracture extending from the lingual margin to the facial

Fitness of Bt-resistant cabbage loopers on Bt cotton plants.

Science.gov (United States)

Tetreau, Guillaume; Wang, Ran; Wang, Ping

2017-10-01

Development of resistance to the insecticidal toxins from Bacillus thuringiensis (Bt) in insects is the major threat to the continued success of transgenic Bt crops in agriculture. The fitness of Bt-resistant insects on Bt and non-Bt plants is a key parameter that determines the development of Bt resistance in insect populations. In this study, a comprehensive analysis of the fitness of Bt-resistant Trichoplusia ni strains on Bt cotton leaves was conducted. The Bt-resistant T. ni strains carried two genetically independent mechanisms of resistance to Bt toxins Cry1Ac and Cry2Ab. The effects of the two resistance mechanisms, individually and in combination, on the fitness of the T. ni strains on conventional non-Bt cotton and on transgenic Bt cotton leaves expressing a single-toxin Cry1Ac (Bollgard I) or two Bt toxins Cry1Ac and Cry2Ab (Bollgard II) were examined. The presence of Bt toxins in plants reduced the fitness of resistant insects, indicated by decreased net reproductive rate (R 0 ) and intrinsic rate of increase (r). The reduction in fitness in resistant T. ni on Bollgard II leaves was greater than that on Bollgard I leaves. A 12.4-day asynchrony of adult emergence between the susceptible T. ni grown on non-Bt cotton leaves and the dual-toxin-resistant T. ni on Bollgard II leaves was observed. Therefore, multitoxin Bt plants not only reduce the probability for T. ni to develop resistance but also strongly reduce the fitness of resistant insects feeding on the plants. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Use of hereditary for the detection of radioinduced variability in the height of tomato plants

International Nuclear Information System (INIS)

Fundora, Z.; Perez Talavera, S.; Auchet, F.; Moya, C.

1986-01-01

This paper is about the study of induced variability in the height of tomato plants from seeds treated with Co-60 gamma-rays. Hereditary coefficients in narrow sense were used trough progenitor-descendant regression of varieties irradiated on the control as indicator of the variability induced by the different doses

The influence of silvicultural practices on genetic improvement: height growth and weevil resistance in eastern white pine

Science.gov (United States)

F. Thomas Ledig; D.M. Smith

1981-01-01

When grown in a common environment, the progeny of white pine (Pinus strobus L.) from weeviled stands improved by selection thinning outperformed the progeny of wolfy dominants from untreated stands in both height and weevil resistance. Within families, weevils tended to attack the tallest trees. Among families the relationship was not as strong and...

Induced mutations in beans and peas for resistance to rust

International Nuclear Information System (INIS)

Fadl, F.A.M.

1983-01-01

Gamma rays and ethyl methanesulphonate (EMS) were applied in a mutation-induction programme for rust resistance in bean and pea. Bean and pea seeds were pre-soaked 2 hours before irradiation with 9, 10 and 12 krad. For chemical mutagen treatments bean and pea seeds were pre-soaked for 8 hours and treated with 0.5 and 1.5% EMS for four hours. M 2 seeds of beans and peas were planted in 1979. Resistant M 2 plants were selected for their rust resistance and other morphological characters. M 3 seeds of selected plants were planted in 1980. In 1980 more seeds of the same varieties of beans and peas were treated with 0.1 and 0.3% EMS with the aim to produce rust-resistant mutants. Seed germination was reduced by gamma rays or EMS. Dwarf, malformed and abnormal plants were noticed. Some resistant M 2 plants selected gave high grain yields. Some were different in morphological characters. In the M 3 of selected plants various other mutant characters appeared, such as different height of plants, early and late flowering, resistance to powdery mildew in peas, altered grain yield, thickness of stem, pod shape and flower colour. (author)

In-Field High-Throughput Phenotyping of Cotton Plant Height Using LiDAR

OpenAIRE

Shangpeng Sun; Changying Li; Andrew H. Paterson

2017-01-01

A LiDAR-based high-throughput phenotyping (HTP) system was developed for cotton plant phenotyping in the field. The HTP system consists of a 2D LiDAR and an RTK-GPS mounted on a high clearance tractor. The LiDAR scanned three rows of cotton plots simultaneously from the top and the RTK-GPS was used to provide the spatial coordinates of the point cloud during data collection. Configuration parameters of the system were optimized to ensure the best data quality. A height profile for each plot w...

Monoterpenes Support Systemic Acquired Resistance within and between Plants.

Science.gov (United States)

Riedlmeier, Marlies; Ghirardo, Andrea; Wenig, Marion; Knappe, Claudia; Koch, Kerstin; Georgii, Elisabeth; Dey, Sanjukta; Parker, Jane E; Schnitzler, Jörg-Peter; Vlot, A Corina

2017-06-01

This study investigates the role of volatile organic compounds in systemic acquired resistance (SAR), a salicylic acid (SA)-associated, broad-spectrum immune response in systemic, healthy tissues of locally infected plants. Gas chromatography coupled to mass spectrometry analyses of SAR-related emissions of wild-type and non-SAR-signal-producing mutant plants associated SAR with monoterpene emissions. Headspace exposure of Arabidopsis thaliana to a mixture of the bicyclic monoterpenes α-pinene and β-pinene induced defense, accumulation of reactive oxygen species, and expression of SA- and SAR-related genes, including the SAR regulatory AZELAIC ACID INDUCED1 ( AZI1 ) gene and three of its paralogs. Pinene-induced resistance was dependent on SA biosynthesis and signaling and on AZI1 Arabidopsis geranylgeranyl reductase1 mutants with reduced monoterpene biosynthesis were SAR-defective but mounted normal local resistance and methyl salicylate-induced defense responses, suggesting that monoterpenes act in parallel with SA The volatile emissions from SAR signal-emitting plants induced defense in neighboring plants, and this was associated with the presence of α-pinene, β-pinene, and camphene in the emissions of the "sender" plants. Our data suggest that monoterpenes, particularly pinenes, promote SAR, acting through ROS and AZI1 , and likely function as infochemicals in plant-to-plant signaling, thus allowing defense signal propagation between neighboring plants. © 2017 American Society of Plant Biologists. All rights reserved.

The role of ethylene perception in plant disease resistance

NARCIS (Netherlands)

Geraats, Bart Peter Johan

2003-01-01

Ethylene is a plant hormone that is involved in responses of the plant to various stress situations, such as pathogen attack. The role of ethylene in plant-pathogen interactions seems to be diverse. Exposure of plants to ethylene can induce disease resistance, but treatment with ethylene during

Effects of N+ implantation on polysaccharide and osmosis stress resistance of liquorice

International Nuclear Information System (INIS)

Wei Shenglin; Wu Lijun; Yu Zengliang

2007-01-01

In order to study the effects of N + implantation on osmosis stress resistance of plant, the experiment was taken with liquorice as plant model and 15% PEG as the osmosis stress agent. The results showed that the stem height growth of liquorice increased by 40.2% compared with controls (p + implantation parameters may be useful to increase osmosis stress resistance cultivation of liquorice and to make it mutated with ions beam implantation. (authors)

Inheritance of culm height and grain yield in durum wheat

International Nuclear Information System (INIS)

Filev, K.

1984-01-01

Results from a study of GA sensitive and GA insensitive durum wheat mutants and cultivars in relation with their culm height and 1000 grain weight are presented. With increasing culm height, the GA response also increased. A positive correlation between plant height and GA response was found. Crosses were made between durum wheats and the F 1 and F 2 progenies were analysed. A different inheritance in F 1 and segregation in F 2 was obtained in crosses of a semi-dwarf, GA insensitive [1] line with GA sensitive (S) lines differing in height, medium (93.2cm) and tall (133.5cm). In a reciprocal cross, semi-dwarf - I with medium - S, the semi-dwarf type was dominant in F 1 , suggesting that their semi-dwarfing genes were not allelic. When the semi-dwarf - I and tall - S were crossed an intermediate inheritance in F 1 was observed. In the F 2 generation from crosses semi-dwarf - I with medium - S with semi-dwarf - I, a phenotypic dihybred segregation 9:3:3:1 was observed. In crosses semi-dwarf - I with tall - S different variation curves were obtained. Semi-dwarfs with high productivity were observed in F 2 , a fact indicating that lodging resistant lines with high yields could be selected. (author)

High-throughput phenotyping of plant resistance to aphids by automated video tracking.

Science.gov (United States)

Kloth, Karen J; Ten Broeke, Cindy Jm; Thoen, Manus Pm; Hanhart-van den Brink, Marianne; Wiegers, Gerrie L; Krips, Olga E; Noldus, Lucas Pjj; Dicke, Marcel; Jongsma, Maarten A

2015-01-01

Piercing-sucking insects are major vectors of plant viruses causing significant yield losses in crops. Functional genomics of plant resistance to these insects would greatly benefit from the availability of high-throughput, quantitative phenotyping methods. We have developed an automated video tracking platform that quantifies aphid feeding behaviour on leaf discs to assess the level of plant resistance. Through the analysis of aphid movement, the start and duration of plant penetrations by aphids were estimated. As a case study, video tracking confirmed the near-complete resistance of lettuce cultivar 'Corbana' against Nasonovia ribisnigri (Mosely), biotype Nr:0, and revealed quantitative resistance in Arabidopsis accession Co-2 against Myzus persicae (Sulzer). The video tracking platform was benchmarked against Electrical Penetration Graph (EPG) recordings and aphid population development assays. The use of leaf discs instead of intact plants reduced the intensity of the resistance effect in video tracking, but sufficiently replicated experiments resulted in similar conclusions as EPG recordings and aphid population assays. One video tracking platform could screen 100 samples in parallel. Automated video tracking can be used to screen large plant populations for resistance to aphids and other piercing-sucking insects.

Engineering Plants for Geminivirus Resistance with CRISPR/Cas9 System

KAUST Repository

Zaidi, Syed Shan-e-Ali; Mansoor, Shahid; Ali, Zahir; Tashkandi, Manal; Mahfouz, Magdy M.

2016-01-01

The CRISPR/Cas9 system is an efficient genome-editing platform for diverse eukaryotic species, including plants. Recent work harnessed CRISPR/Cas9 technology to engineer resistance to geminiviruses. Here, we discuss opportunities, emerging developments, and potential pitfalls for using this technology to engineer resistance against single and multiple geminivirus infections in plants.

Engineering Plants for Geminivirus Resistance with CRISPR/Cas9 System

KAUST Repository

Zaidi, Syed Shan-e-Ali

2016-02-14

The CRISPR/Cas9 system is an efficient genome-editing platform for diverse eukaryotic species, including plants. Recent work harnessed CRISPR/Cas9 technology to engineer resistance to geminiviruses. Here, we discuss opportunities, emerging developments, and potential pitfalls for using this technology to engineer resistance against single and multiple geminivirus infections in plants.

Study and Evaluation of Ultrasound System for Detecting the Height of Corn Canopy

Directory of Open Access Journals (Sweden)

T Mesri Gundoshmian

2017-10-01

Full Text Available Introduction Growth of population, deficiency of resources, environmental hazards, fast spatial science progress and relevant subjects have resulted in significant effects of enhanced accuracy and modern technologies in agricultural technology and management methods. One of the modern technologies’ utilities in production and nondestructive tests is determination of product characteristics (such as product height, using electronic sensors at different stages of plant growth. In recent years, electric sensors improved widely in farm science. Regarding to wide performance of sensors, from simple sensors such as thermo, light and moisture sensors, to complex ones such as GPS and lidar, also the ability of electronic sensors to exact identification and measurement of special farm properties, makes these sensors to an important part of precision agriculture. The subject of this study is to identify and measure the height of the product using ultrasonic technology to automate control of breeding and harvesting operations. Suitable price and noise and dust resistance of ultrasonic sensor, make it an attractive subject in biosystem industries and farm operations. Materials and Methods Plant height measurement Ultrasonic sensor includes an ultrasonic transmitter and receiver with more than 20 kHz frequency. As other waves, ultrasonic waves diffuse constantly from a source by mechanical distracting in a gas, liquid or solid environment. The distance between sensor and object is a function of the wave passing time from generation point to receive point. Plant height calculated by estimating this distance and minus it from sensor height. The sensor used in this research had a diffuse angle of 40 degrees to center axis of source. The sensor ability to height measurement depends on leaves angle, leaves surface, plant aggregation in area and plant height. Leaves angle is the most important factor in recognization ability of ultrasonic sensor. Electronic

Receptor-like proteins involved in plant disease resistance

NARCIS (Netherlands)

Kruijt, M.; Kock, de M.J.D.; Wit, de P.J.G.M.

2005-01-01

Race-specific resistance in plants against microbial pathogens is governed by several distinct classes of resistance (R) genes. This review focuses on the class that consists of the plasma membrane-bound leucine-rich repeat proteins known as receptor-like proteins (RLPs). The first isolated

Presence of Methicillin Resistant Staphylococcus aureus (MRSA) in sewage treatment plant.

Science.gov (United States)

Boopathy, Raj

2017-09-01

The presence of antibiotic resistant bacteria and antibiotic resistance genes in rural sewage treatment plants are not well reported in the literature. The aim of the present study was to study the frequency occurrence of Methicillin Resistant Staphylococcus aureus (MRSA) in a rural sewage treatment plant. This study was conducted using raw sewage as well as treated sewage from a small town sewage treatment plant in rural southeast Louisiana of USA. Results showed the presence of MRSA consistently in both raw and treated sewage. The presence of mecA gene responsible for methicillin resistance was confirmed in the raw and treated sewage water samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

Induced disease resistance signaling in plants

NARCIS (Netherlands)

Verhagen, B.W.M.; Loon, L.C. van; Pieterse, C.M.J.

2006-01-01

To protect themselves from disease, plants have evolved sophisticated inducible defense mechanisms in which the signal molecules salicylic acid, jasmonic acid and ethylene often play crucial roles. Elucidation of signaling pathways controlling induced disease resistance is a major objective in

Stress proteins and phytohormones: their role in formation of plant resistance

International Nuclear Information System (INIS)

Kosakivska, I.V.

2005-01-01

Full text: Using the disc-electrophoresis methods, we have studied protein biosynthesis of different plants, including 11 species of Orchidaceae, some other tropical and subtropical plants, 9 different fruit plants, and 4 cultivars of Triticum aestivum L. under stresses factors such as high and low temperature, clinostating, radioactive irradiation and osmotic shock. Specific and unspecific reactions of plants protein system on stresses were found. De novo synthesis of 35 and 45 kD polypeptides were observed in total and mitochondrial proteins fractions after heat-shock and radioactive irradiation. This suggests that mitochondries participate in formation of plant resistance. Intensive synthesis of ABA revealed as the universal reaction of all studied plants on action of different kinds of stresses. Specific changes in balance of phytohormones were found under different stresses. We observed the correlation between endogenous ABA, IAA and cytokinin level and plant resistance. We also found the interaction between the process of biosynthesis of proteins and phytohormone balance, as well as their direct participation in formation of plant resistance. (author)

Herbicide resistance and biodiversity: agronomic and environmental aspects of genetically modified herbicide-resistant plants.

Science.gov (United States)

Schütte, Gesine; Eckerstorfer, Michael; Rastelli, Valentina; Reichenbecher, Wolfram; Restrepo-Vassalli, Sara; Ruohonen-Lehto, Marja; Saucy, Anne-Gabrielle Wuest; Mertens, Martha

2017-01-01

Farmland biodiversity is an important characteristic when assessing sustainability of agricultural practices and is of major international concern. Scientific data indicate that agricultural intensification and pesticide use are among the main drivers of biodiversity loss. The analysed data and experiences do not support statements that herbicide-resistant crops provide consistently better yields than conventional crops or reduce herbicide amounts. They rather show that the adoption of herbicide-resistant crops impacts agronomy, agricultural practice, and weed management and contributes to biodiversity loss in several ways: (i) many studies show that glyphosate-based herbicides, which were commonly regarded as less harmful, are toxic to a range of aquatic organisms and adversely affect the soil and intestinal microflora and plant disease resistance; the increased use of 2,4-D or dicamba, linked to new herbicide-resistant crops, causes special concerns. (ii) The adoption of herbicide-resistant crops has reduced crop rotation and favoured weed management that is solely based on the use of herbicides. (iii) Continuous herbicide resistance cropping and the intensive use of glyphosate over the last 20 years have led to the appearance of at least 34 glyphosate-resistant weed species worldwide. Although recommended for many years, farmers did not counter resistance development in weeds by integrated weed management, but continued to rely on herbicides as sole measure. Despite occurrence of widespread resistance in weeds to other herbicides, industry rather develops transgenic crops with additional herbicide resistance genes. (iv) Agricultural management based on broad-spectrum herbicides as in herbicide-resistant crops further decreases diversity and abundance of wild plants and impacts arthropod fauna and other farmland animals. Taken together, adverse impacts of herbicide-resistant crops on biodiversity, when widely adopted, should be expected and are indeed very hard

Cadmium resistance in tobacco plants expressing the MuSI gene

OpenAIRE

Kim, Young-Nam; Kim, Ji-Seoung; Seo, Sang-Gyu; Lee, Youngwoo; Baek, Seung-Woo; Kim, Il-Sup; Yoon, Ho-Sung; Kim, Kwon-Rae; Kim, Sun-Hyung; Kim, Kye-Hoon

2011-01-01

MuSI, a gene that corresponds to a domain that contains the rubber elongation factor (REF), is highly homologous to many stress-related proteins in plants. Since MuSI is up-regulated in the roots of plants treated with cadmium or copper, the involvement of MuSI in cadmium tolerance was investigated in this study. Escherichia coli cells overexpressing MuSI were more resistant to Cd than wild-type cells transfected with vector alone. MuSI transgenic plants were also more resistant to Cd. MuSI t...

Increased resistance to a generalist herbivore in a salinity-stressed non-halophytic plant.

Science.gov (United States)

Renault, Sylvie; Wolfe, Scott; Markham, John; Avila-Sakar, Germán

2016-01-01

Plants often grow under the combined stress of several factors. Salinity and herbivory, separately, can severely hinder plant growth and reproduction, but the combined effects of both factors are still not clearly understood. Salinity is known to reduce plant tissue nitrogen content and growth rates. Since herbivores prefer tissues with high N content, and biochemical pathways leading to resistance are commonly elicited by salt-stress, we hypothesized that plants growing in saline conditions would have enhanced resistance against herbivores. The non-halophyte, Brassica juncea, and the generalist herbivore Trichoplusia ni were used to test the prediction that plants subjected to salinity stress would be both more resistant and more tolerant to herbivory than those growing without salt stress. Plants were grown under different NaCl levels, and either exposed to herbivores and followed by removal of half of their leaves, or left intact. Plants were left to grow and reproduce until senescence. Tissue quality was assessed, seeds were counted and biomass of different organs measured. Plants exposed to salinity grew less, had reduced tissue nitrogen, protein and chlorophyll content, although proline levels increased. Specific leaf area, leaf water content, transpiration and root:shoot ratio remained unaffected. Plants growing under saline condition had greater constitutive resistance than unstressed plants. However, induced resistance and tolerance were not affected by salinity. These results support the hypothesis that plants growing under salt-stress are better defended against herbivores, although in B. juncea this may be mostly through resistance, and less through tolerance. Published by Oxford University Press on behalf of the Annals of Botany Company.

The role of aluminum sensing and signaling in plant aluminum resistance.

Science.gov (United States)

Liu, Jiping; Piñeros, Miguel A; Kochian, Leon V

2014-03-01

As researchers have gained a better understanding in recent years into the physiological, molecular, and genetic basis of how plants deal with aluminum (Al) toxicity in acid soils prevalent in the tropics and sub-tropics, it has become clear that an important component of these responses is the triggering and regulation of cellular pathways and processes by Al. In this review of plant Al signaling, we begin by summarizing the understanding of physiological mechanisms of Al resistance, which first led researchers to realize that Al stress induces gene expression and modifies protein function during the activation of Al resistance responses. Subsequently, an overview of Al resistance genes and their function provides verification that Al induction of gene expression plays a major role in Al resistance in many plant species. More recent research into the mechanistic basis for Al-induced transcriptional activation of resistance genes has led to the identification of several transcription factors as well as cis-elements in the promoters of Al resistance genes that play a role in greater Al-induced gene expression as well as higher constitutive expression of resistance genes in some plant species. Finally, the post-transcriptional and translational regulation of Al resistance proteins is addressed, where recent research has shown that Al can both directly bind to and alter activity of certain organic acid transporters, and also influence Al resistance proteins indirectly, via protein phosphorylation. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Quantitative Resistance to Plant Pathogens in Pyramiding Strategies for Durable Crop Protection

Directory of Open Access Journals (Sweden)

Marie-Laure Pilet-Nayel

2017-10-01

Full Text Available Quantitative resistance has gained interest in plant breeding for pathogen control in low-input cropping systems. Although quantitative resistance frequently has only a partial effect and is difficult to select, it is considered more durable than major resistance (R genes. With the exponential development of molecular markers over the past 20 years, resistance QTL have been more accurately detected and better integrated into breeding strategies for resistant varieties with increased potential for durability. This review summarizes current knowledge on the genetic inheritance, molecular basis, and durability of quantitative resistance. Based on this knowledge, we discuss how strategies that combine major R genes and QTL in crops can maintain the effectiveness of plant resistance to pathogens. Combining resistance QTL with complementary modes of action appears to be an interesting strategy for breeding effective and potentially durable resistance. Combining quantitative resistance with major R genes has proven to be a valuable approach for extending the effectiveness of major genes. In the plant genomics era, improved tools and methods are becoming available to better integrate quantitative resistance into breeding strategies. Nevertheless, optimal combinations of resistance loci will still have to be identified to preserve resistance effectiveness over time for durable crop protection.

Release of Antibiotic Resistant Bacteria by a Waste Treatment Plant from Romania.

Science.gov (United States)

Lupan, Iulia; Carpa, Rahela; Oltean, Andreea; Kelemen, Beatrice Simona; Popescu, Octavian

2017-09-27

The occurrence and spread of bacterial antibiotic resistance are subjects of great interest, and the role of wastewater treatment plants has been attracting particular interest. These stations are a reservoir of bacteria, have a large range of organic and inorganic substances, and the amount of bacteria released into the environment is very high. The main purpose of the present study was to assess the removal degree of bacteria with resistance to antibiotics and identify the contribution of a wastewater treatment plant to the microbiota of Someşul Mic river water in Cluj county. The resistance to sulfamethoxazole and tetracycline and some of their representative resistance genes: sul1, tet(O), and tet(W) were assessed in this study. The results obtained showed that bacteria resistant to sulphonamides were more abundant than those resistant to tetracycline. The concentration of bacteria with antibiotic resistance changed after the treatment, namely, bacteria resistant to sulfamethoxazole. The removal of all bacteria and antibiotic-resistant bacteria was 98-99% and the degree of removal of bacteria resistant to tetracycline was higher than the bacteria resistant to sulfamethoxazole compared to total bacteria. The wastewater treatment plant not only contributed to elevating ARG concentrations, it also enhanced the possibility of horizontal gene transfer (HGT) by increasing the abundance of the intI1 gene. Even though the treatment process reduced the concentration of bacteria by two orders of magnitude, the wastewater treatment plant in Cluj-Napoca contributed to an increase in antibiotic-resistant bacteria concentrations up to 10 km downstream of its discharge in Someşul Mic river.

The effect of ratio between rigid plant height and water depth on the manning’s coefficient in open channel

Science.gov (United States)

Rizalihadi, M.; Ziana; Shaskia, Nina; Asharly, H.

2018-05-01

One of the important factors in channel dimension is the Manning’s coefficient ( n ). This coefficient is influenced not only by the channel roughness but also by the presence of plants in the channel. The aim of the study is to see the effect of the ratio between the height of the rigid plant and water depth on the Manning’s coefficient (n) in open channel. The study was conducted in open channel with 15.5 m long, 0.5 m wide and 1.0 m high, in which at the center of the channel is planted with the rigid plants with a density of 42 plants/m2. The flow was run with a discharge of 0.013 m3/s at 6 ratios of Hplants/Hwater, namely: 0; 0.2; 0.6; 0.8; 1,0 and 1,2, to obtain the velocity and water profiles. Then the value of n is analyzed using Manning’s equation. The results showed that the mean velocity becomes decrease 17.81-34.01% as increase the ratio of Hplants/Hwater. This results in increasing n value to become 1.22-1.52 times compared to the unplanted channel ( no =0.038). So, it can be concluded that the ratio between the rigid plant’s height and water depth in the open channel can affect the value of Manning coefficient.

Plant breeding for resistance to insect pests: Considerations about the use of induced mutations

International Nuclear Information System (INIS)

1978-01-01

The Panel was intended to stimulate proposals on specific plant breeding objectives, for immediate and long term solution. Nine papers considered the host plant resistance to particular insect pests in a variety of cases. The desirability of achieving some measure of pest control via the development of disease-resistant mutants was discussed. In its conclusions, the Panel stressed the need to consider host plant resistance as one of the primary lines of defense in all pest management programmes. Consequently, resistance to insects was recommended to become an integral part of plant breeding programmes. Preference might need to be given to developing insect resistance in those crop plants for which practical control is lacking or where current methods of pest control present critical environmental hazards. The roles of the IAEA and FAO in such projects is outlined. Guidelines and recommendations on mutation breeding for resistance to insects are given in an appendix

Metal resistant plants and phytoremediation of environmental contamination

Science.gov (United States)

Meagher, Richard B.; Li, Yujing; Dhankher, Om P.

2010-04-20

The present disclosure provides a method of producing transgenic plants which are resistant to at least one metal ion by transforming the plant with a recombinant DNA comprising a nucleic acid encoding a bacterial arsenic reductase under the control of a plant expressible promoter, and a nucleic acid encoding a nucleotide sequence encoding a phytochelatin biosynthetic enzyme under the control of a plant expressible promoter. The invention also relates a method of phytoremediation of a contaminated site by growing in the site a transgenic plant expressing a nucleic acid encoding a bacterial arsenate reductase and a nucleic acid encoding a phytochelatin biosynthetic enzyme.

Enhanced resistance to Spodoptera litura in endophyte infected cauliflower plants.

Science.gov (United States)

Thakur, Abhinay; Kaur, Sanehdeep; Kaur, Amarjeet; Singh, Varinder

2013-04-01

Endophytic fungi, which live within host plant tissues without causing any visible symptom of disease, are important mediators of plant-herbivore interactions. These endophytes enhance resistance of host plant against insect herbivores mainly by productions of various alkaloid based defensive compounds in the plant tissue or through alterations of plant nutritional quality. Two endophytic fungi, i.e., Nigrospora sp. and Cladosporium sp., were isolated from Tinospora cordifolia (Thunb.) Miers, a traditional indian medicinal plant. Cauliflower (Brassica oleracea L.) plants were inoculated with these two endophytic fungi. The effect of endophyte infected and uninfected cauliflower plants were measured on the survival and development of Spodoptera litura (Fab.), a polyphagous pest. Endophyte infected cauliflower plants showed resistance to S. litura in the form of significant increase in larval and pupal mortality in both the fungi. Inhibitory effects of endophytic fungi also were observed on adult emergence, longevity, reproductive potential, as well as hatchability of eggs. Thus, it is concluded that antibiosis to S. litura could be imparted by artificial inoculation of endophytes and this could be used to develop alternative ecologically safe control strategies.

Gibberellins Promote Brassinosteroids Action and Both Increase Heterosis for Plant Height in Maize (Zea mays L.

Directory of Open Access Journals (Sweden)

Songlin Hu

2017-06-01

Full Text Available Brassinosteroids (BRs and Gibberellins (GAs are two classes of plant hormones affecting plant height (PHT. Thus, manipulation of BR and GA levels or signaling enables optimization of crop grain and biomass yields. We established backcross (BC families, selected for increased PHT, in two elite maize inbred backgrounds. Various exotic accessions used in the germplasm enhancement in maize project served as donors. BC1-derived doubled haploid lines in the same two elite maize inbred backgrounds established without selection for plant height were included for comparison. We conducted genome-wide association studies to explore the genetic control of PHT by BR and GA. In addition, we used BR and GA inhibitors to compare the relationship between PHT, BR, and GA in inbred lines and heterozygotes from a physiological and biological perspective. A total of 73 genomic loci were discovered to be associated with PHT, with seven co-localized with GA, and two co-localized with BR candidate genes. PHT determined in field trials was significantly correlated with seedling stage BR and GA inhibitor responses. However, this observation was only true for maize heterozygotes, not for inbred lines. Path analysis results suggest that heterozygosity increases GA levels, which in turn promote BR levels. Thus, at least part of heterosis for PHT in maize can be explained by increased GA and BR levels, and seedling stage hormone inhibitor response is promising to predict heterosis for PHT.

New Technologies for Insect-Resistant and Herbicide-Tolerant Plants.

Science.gov (United States)

Lombardo, Luca; Coppola, Gerardo; Zelasco, Samanta

2016-01-01

The advent of modern molecular biology and recombinant DNA technology has resulted in a dramatic increase in the number of insect-resistant (IR) and herbicide-tolerant (HT) plant varieties, with great economic benefits for farmers. Nevertheless, the high selection pressure generated by control strategies for weed and insect populations has led to the evolution of herbicide and pesticide resistance. In the short term, the development of new techniques or the improvement of existing ones will provide further instruments to counter the appearance of resistant weeds and insects and to reduce the use of agrochemicals. In this review, we examine some of the most promising new technologies for developing IR and HT plants, such as genome editing and antisense technologies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bipolar resistive switching in different plant and animal proteins

KAUST Repository

Bag, A.; Hota, Mrinal Kanti; Mallik, Sandipan B.; Maì ti, Chinmay Kumar

2014-01-01

We report bipolar resistive switching phenomena observed in different types of plant and animal proteins. Using protein as the switching medium, resistive switching devices have been fabricated with conducting indium tin oxide (ITO) and Al as bottom and top electrodes, respectively. A clockwise bipolar resistive switching phenomenon is observed in all proteins. It is shown that the resistive switching phenomena originate from the local redox process in the protein and the ion exchange from the top electrode/protein interface.

Bipolar resistive switching in different plant and animal proteins

KAUST Repository

Bag, A.

2014-06-01

We report bipolar resistive switching phenomena observed in different types of plant and animal proteins. Using protein as the switching medium, resistive switching devices have been fabricated with conducting indium tin oxide (ITO) and Al as bottom and top electrodes, respectively. A clockwise bipolar resistive switching phenomenon is observed in all proteins. It is shown that the resistive switching phenomena originate from the local redox process in the protein and the ion exchange from the top electrode/protein interface.

Transgenic strategies to confer resistance against viruses in rice plants

Directory of Open Access Journals (Sweden)

Takahide eSasaya

2014-01-01

Full Text Available Rice (Oryza sativa L. is cultivated in more than 100 countries and supports nearly half of the world’s population. Developing efficient methods to control rice viruses is thus an urgent necessity because viruses cause serious losses in rice yield. Most rice viruses are transmitted by insect vectors, notably planthoppers and leafhoppers. Viruliferous insect vectors can disperse their viruses over relatively long distances, and eradication of the viruses is very difficult once they become widespread. Exploitation of natural genetic sources of resistance is one of the most effective approaches to protect crops from virus infection; however, only a few naturally occurring rice genes confer resistance against rice viruses. In an effort to improve control, many investigators are using genetic engineering of rice plants as a potential strategy to control viral diseases. Using viral genes to confer pathogen-derived resistance against crops is a well-established procedure, and the expression of various viral gene products has proved to be effective in preventing or reducing infection by various plant viruses since the 1990s. RNA-interference (RNAi, also known as RNA silencing, is one of the most efficient methods to confer resistance against plant viruses on their respective crops. In this article, we review the recent progress, mainly conducted by our research group, in transgenic strategies to confer resistance against tenuiviruses and reoviruses in rice plants. Our findings also illustrate that not all RNAi constructs against viral RNAs are equally effective in preventing virus infection and that it is important to identify the viral Achilles’ heel gene to target for RNAi attack when engineering plants.

Radiation resistance of cable insulation and jacket materials for nuclear power plants

International Nuclear Information System (INIS)

Morita, Minoru; Kon, Shuji; Nishikawa, Ichiro

1978-01-01

The cables for use in nuclear power plants are required to satisfy the specific environmental resistance and excellent flame resistance as stipulated in IEEE Std. 383. The materials to be used to cables intended for this specific purpose of use must therefore be strictly tested so as to evaluate their flame resistance in addition to compliance with various environmental requirements, such as heat resistance, water-vapor resistance, and radiation resistance. This paper describes general information on radiation resistance and deterioration of various high-molecular materials, suggests the direction of efforts to be made to improve their properties including flame resistance of various rubber and plastic materials for cables to be used in nuclear power plants, and indicates the performance characteristics of such materials. (author)

Phosphorylation and proteome dynamics in pathogen-resistant tomato plants

NARCIS (Netherlands)

Stulemeijer, I.J.E.

2008-01-01

Microbial plant pathogens impose a continuous threat on global food production. Similar to disease resistance in mammals, an innate immune system allows plants to recognise pathogens and swiftly activate defence. For the work described in this thesis, the interaction between tomato and the

Cadmium resistance in tobacco plants expressing the MuSI gene.

Science.gov (United States)

Kim, Young-Nam; Kim, Ji-Seoung; Seo, Sang-Gyu; Lee, Youngwoo; Baek, Seung-Woo; Kim, Il-Sup; Yoon, Ho-Sung; Kim, Kwon-Rae; Kim, Sun-Hyung; Kim, Kye-Hoon

2011-10-01

MuSI, a gene that corresponds to a domain that contains the rubber elongation factor (REF), is highly homologous to many stress-related proteins in plants. Since MuSI is up-regulated in the roots of plants treated with cadmium or copper, the involvement of MuSI in cadmium tolerance was investigated in this study. Escherichia coli cells overexpressing MuSI were more resistant to Cd than wild-type cells transfected with vector alone. MuSI transgenic plants were also more resistant to Cd. MuSI transgenic tobacco plants absorbed less Cd than wild-type plants. Cd translocation from roots to shoots was reduced in the transgenic plants, thereby avoiding Cd toxicity. The number of short trichomes in the leaves of wild-type tobacco plants was increased by Cd treatment, while this was unchanged in MuSI transgenic tobacco. These results suggest that MuSI transgenic tobacco plants have enhanced tolerance to Cd via reduced Cd uptake and/or increased Cd immobilization in the roots, resulting in less Cd translocation to the shoots.

Genetic and sexual separation between insect resistant and susceptible Barbarea vulgaris plants in Denmark

DEFF Research Database (Denmark)

Toneatto, Fiorello; Nielsen, Jens Kvist; Ørgaard, Marian

2010-01-01

of these interactions, we tested how genetically divergent resistant and susceptible plants are, using microsatellite markers. To test whether they are reproductively fully compatible, resistant and susceptible plants were grown intermixed in an outdoor experiment, and the paternity of open-pollinated offspring......Co-evolution between herbivores and plants is believed to be one of the processes creating Earth’s biodiversity. However, it is difficult to disentangle to what extent diversification is really driven by herbivores or by other historical-geographical processes like allopatric isolation....... In the cruciferous plant Barbarea vulgaris, some Danish individuals are resistant to herbivory by flea beetles (Phyllotreta nemorum), whereas others are not. The flea beetles are, in parallel, either resistant or susceptible to the plants defenses. To understand the historical-evolutionary framework...

Contrasting effects of specialist and generalist herbivores on resistance evolution in invasive plants.

Science.gov (United States)

Zhang, Zhijie; Pan, Xiaoyun; Blumenthal, Dana; van Kleunen, Mark; Liu, Mu; Li, Bo

2018-04-01

Invasive alien plants are likely to be released from specialist herbivores and at the same time encounter biotic resistance from resident generalist herbivores in their new ranges. The Shifting Defense hypothesis predicts that this will result in evolution of decreased defense against specialist herbivores and increased defense against generalist herbivores. To test this, we performed a comprehensive meta-analysis of 61 common garden studies that provide data on resistance and/or tolerance for both introduced and native populations of 32 invasive plant species. We demonstrate that introduced populations, relative to native populations, decreased their resistance against specialists, and increased their resistance against generalists. These differences were significant when resistance was measured in terms of damage caused by the herbivore, but not in terms of performance of the herbivore. Furthermore, we found the first evidence that the magnitude of resistance differences between introduced and native populations depended significantly on herbivore origin (i.e., whether the test herbivore was collected from the native or non-native range of the invasive plant). Finally, tolerance to generalists was found to be higher in introduced populations, while neither tolerance to specialists nor that to simulated herbivory differed between introduced and native plant populations. We conclude that enemy release from specialist herbivores and biotic resistance from generalist herbivores have contrasting effects on resistance evolution in invasive plants. Our results thus provide strong support for the Shifting Defense hypothesis. © 2018 by the Ecological Society of America.

Response of Plant Height, Species Richness and Aboveground Biomass to Flooding Gradient along Vegetation Zones in Floodplain Wetlands, Northeast China.

Science.gov (United States)

Lou, Yanjing; Pan, Yanwen; Gao, Chuanyu; Jiang, Ming; Lu, Xianguo; Xu, Y Jun

2016-01-01

Flooding regime changes resulting from natural and human activity have been projected to affect wetland plant community structures and functions. It is therefore important to conduct investigations across a range of flooding gradients to assess the impact of flooding depth on wetland vegetation. We conducted this study to identify the pattern of plant height, species richness and aboveground biomass variation along the flooding gradient in floodplain wetlands located in Northeast China. We found that the response of dominant species height to the flooding gradient depends on specific species, i.e., a quadratic response for Carex lasiocarpa, a negative correlation for Calamagrostis angustifolia, and no response for Carex appendiculata. Species richness showed an intermediate effect along the vegetation zone from marsh to wet meadow while aboveground biomass increased. When the communities were analysed separately, only the water table depth had significant impact on species richness for two Carex communities and no variable for C. angustifolia community, while height of dominant species influenced aboveground biomass. When the three above-mentioned communities were grouped together, variations in species richness were mainly determined by community type, water table depth and community mean height, while variations in aboveground biomass were driven by community type and the height of dominant species. These findings indicate that if habitat drying of these herbaceous wetlands in this region continues, then two Carex marshes would be replaced gradually by C. angustifolia wet meadow in the near future. This will lead to a reduction in biodiversity and an increase in productivity and carbon budget. Meanwhile, functional traits must be considered, and should be a focus of attention in future studies on the species diversity and ecosystem function in this region.

Cytotoxicity of South-African medicinal plants towards sensitive and multidrug-resistant cancer cells.

Science.gov (United States)

Saeed, Mohamed E M; Meyer, Marion; Hussein, Ahmed; Efferth, Thomas

2016-06-20

Traditional medicine plays a major role for primary health care worldwide. Cancer belongs to the leading disease burden in industrialized and developing countries. Successful cancer therapy is hampered by the development of resistance towards established anticancer drugs. In the present study, we investigated the cytotoxicity of 29 extracts from 26 medicinal plants of South-Africa against leukemia cell lines, most of which are used traditionally to treat cancer and related symptoms. We have investigated the plant extracts for their cytotoxic activity towards drug-sensitive parental CCRF-CEM leukemia cells and their multidrug-resistant P-glycoprotein-overexpressing subline, CEM/ADR5000 by means of the resazurin assay. A panel of 60 NCI tumor cell lines have been investigated for correlations between selected phytochemicals from medicinal plants and the expression of resistance-conferring genes (ABC-transporters, oncogenes, tumor suppressor genes). Seven extracts inhibited both cell lines (Acokanthera oppositifolia, Hypoestes aristata, Laurus nobilis, Leonotis leonurus, Plectranthus barbatus, Plectranthus ciliates, Salvia apiana). CEM/ADR5000 cells exhibited a low degree of cross-resistance (3.35-fold) towards the L. leonurus extract, while no cross-resistance was observed to other plant extracts, although CEM/ADR5000 cells were highly resistant to clinically established drugs. The log10IC50 values for two out of 14 selected phytochemicals from these plants (acovenoside A and ouabain) of 60 tumor cell lines were correlated to the expression of ABC-transporters (ABCB1, ABCB5, ABCC1, ABCG2), oncogenes (EGFR, RAS) and tumor suppressors (TP53). Sensitivity or resistance of the cell lines were not statistically associated with the expression of these genes, indicating that multidrug-resistant, refractory tumors expressing these genes may still respond to acovenoside A and ouabain. The bioactivity of South African medicinal plants may represent a basis for the development

Phenotypic characterization, genetic mapping and candidate gene analysis of a source conferring reduced plant height in sunflower.

Science.gov (United States)

Ramos, María Laura; Altieri, Emiliano; Bulos, Mariano; Sala, Carlos A

2013-01-01

Reduced height germplasm has the potential to increase stem strength, standability, and also yields potential of the sunflower crop (Helianthus annuus L. var. macrocarpus Ckll.). In this study, we report on the inheritance, mapping, phenotypic and molecular characterization of a reduced plant height trait in inbred lines derived from the source DDR. This trait is controlled by a semidominant allele, Rht1, which maps on linkage group 12 of the sunflower public consensus map. Phenotypic effects of this allele include shorter height and internode length, insensibility to exogenous gibberellin application, normal skotomorphogenetic response, and reduced seed set under self-pollination conditions. This later effect presumably is related to the reduced pollen viability observed in all DDR-derived lines studied. Rht1 completely cosegregated with a haplotype of the HaDella1 gene sequence. This haplotype consists of a point mutation converting a leucine residue in a proline within the conserved DELLA domain. Taken together, the phenotypic, genetic, and molecular results reported here indicate that Rht1 in sunflower likely encodes an altered DELLA protein. If the DELPA motif of the HaDELLA1 sequence in the Rht1-encoded protein determines by itself the observed reduction in height is a matter that remains to be investigated.

Modified cellulose synthase gene from Arabidopsis thaliana confers herbicide resistance to plants

Science.gov (United States)

Somerville, Chris R [Portola Valley, CA; Scheible, Wolf [Golm, DE

2007-07-10

Cellulose synthase ("CS"), a key enzyme in the biosynthesis of cellulose in plants is inhibited by herbicides comprising thiazolidinones such as 5-tert-butyl-carbamoyloxy-3-(3-trifluromethyl)phenyl-4-thiazolidinone (TZ), isoxaben and 2,6-dichlorobenzonitrile (DCB). Two mutant genes encoding isoxaben and TZ-resistant cellulose synthase have been isolated from isoxaben and TZ-resistant Arabidopsis thaliana mutants. When compared with the gene coding for isoxaben or TZ-sensitive cellulose synthase, one of the resistant CS genes contains a point mutation, wherein glycine residue 998 is replaced by an aspartic acid. The other resistant mutation is due to a threonine to isoleucine change at amino acid residue 942. The mutant CS gene can be used to impart herbicide resistance to a plant; thereby permitting the utilization of the herbicide as a single application at a concentration which ensures the complete or substantially complete killing of weeds, while leaving the transgenic crop plant essentially undamaged.

Food plant derived disease tolerance and resistance in a natural butterfly-plant-parasite interactions.

Science.gov (United States)

Sternberg, Eleanore D; Lefèvre, Thierry; Li, James; de Castillejo, Carlos Lopez Fernandez; Li, Hui; Hunter, Mark D; de Roode, Jacobus C

2012-11-01

Organisms can protect themselves against parasite-induced fitness costs through resistance or tolerance. Resistance includes mechanisms that prevent infection or limit parasite growth while tolerance alleviates the fitness costs from parasitism without limiting infection. Although tolerance and resistance affect host-parasite coevolution in fundamentally different ways, tolerance has often been ignored in animal-parasite systems. Where it has been studied, tolerance has been assumed to be a genetic mechanism, unaffected by the host environment. Here we studied the effects of host ecology on tolerance and resistance to infection by rearing monarch butterflies on 12 different species of milkweed food plants and infecting them with a naturally occurring protozoan parasite. Our results show that monarch butterflies experience different levels of tolerance to parasitism depending on the species of milkweed that they feed on, with some species providing over twofold greater tolerance than other milkweed species. Resistance was also affected by milkweed species, but there was no relationship between milkweed-conferred resistance and tolerance. Chemical analysis suggests that infected monarchs obtain highest fitness when reared on milkweeds with an intermediate concentration, diversity, and polarity of toxic secondary plant chemicals known as cardenolides. Our results demonstrate that environmental factors-such as interacting species in ecological food webs-are important drivers of disease tolerance. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

Induced resistance in plants and the role of pathogenesis-related proteins

NARCIS (Netherlands)

Loon, L.C. van

1997-01-01

The nature of induced resistance Resistance, according to Agrios (1988) is the ability of an organism to exclude or overcome, completely or in some degree, the effect of a pathogen or other damaging factor. Disease resistance in plants is manifested by limited symptoms, reflecting the

Nematode parasites of animals are more prone to develop xenobiotic resistance than nematode parasites of plants

Directory of Open Access Journals (Sweden)

Silvestre A.

2004-06-01

Full Text Available In this paper, we concentrate on a comparison of plant and animal-parasitic nematodes, to gain insight into the factors that influence the acquisition of the drug resistance by nematodes. Comparing nematode parasite of domestic animals and cultivated plants, it appears that drug resistance threatens only domestic animal production. Does the paucity of report on nematicide field resistance reflect reality or, is nematicide resistance bypassed by other management practices, specific to cultivated plants (i.e. agricultural control ? First, it seems that selection pressure by treatments in plants is not as efficient as selection pressure in ruminants. Agronomic practices (i.e. sanitation, early planting, usage of nematodes resistant cultivar and crop rotation are frequently used to control parasitic-plant nematodes. Although the efficiency of such measures is generally moderate to high, integrated approaches are developing successfully in parasitic-plant nematode models. Secondly, the majority of anthelmintic resistance cases recorded in animal-parasitic nematodes concern drug families that are not used in plant-parasitic nematodes control (i.e. benzimidazoles, avermectines and levamisole. Thirdly, particular life traits of parasitic-plant nematodes (low to moderate fecundity and reproductive strategy are expected to reduce probability of appearance and transmission of drug resistance genes. It has been demonstrated that, for a large number of nematodes such as Meloidogyne spp., the mode of reproduction by mitotic parthenogenesis reduced genetic diversity of populations which may prevent a rapid drug resistance development. In conclusion, anthelmintic resistance develops in nematode parasite of animals as a consequence of an efficient selection pressure. Early detection of anthelmintic resistance is then crucial : it is not possible to avoid it, but only to delay its development in farm animal industry.

A specialist root herbivore reduces plant resistance and uses an induced plant volatile to aggregate in a density dependent manner

Science.gov (United States)

1. Leaf-herbivore attack often triggers induced resistance in plants. However, certain specialist herbivores can also take advantage of the induced metabolic changes. In some cases, they even manipulate plant resistance, leading to a phenomenon called induced susceptibility. Compared to above-ground...

Response of Plant Height, Species Richness and Aboveground Biomass to Flooding Gradient along Vegetation Zones in Floodplain Wetlands, Northeast China

Science.gov (United States)

Lou, Yanjing; Pan, Yanwen; Gao, Chuanyu; Jiang, Ming; Lu, Xianguo; Xu, Y. Jun

2016-01-01

Flooding regime changes resulting from natural and human activity have been projected to affect wetland plant community structures and functions. It is therefore important to conduct investigations across a range of flooding gradients to assess the impact of flooding depth on wetland vegetation. We conducted this study to identify the pattern of plant height, species richness and aboveground biomass variation along the flooding gradient in floodplain wetlands located in Northeast China. We found that the response of dominant species height to the flooding gradient depends on specific species, i.e., a quadratic response for Carex lasiocarpa, a negative correlation for Calamagrostis angustifolia, and no response for Carex appendiculata. Species richness showed an intermediate effect along the vegetation zone from marsh to wet meadow while aboveground biomass increased. When the communities were analysed separately, only the water table depth had significant impact on species richness for two Carex communities and no variable for C. angustifolia community, while height of dominant species influenced aboveground biomass. When the three above-mentioned communities were grouped together, variations in species richness were mainly determined by community type, water table depth and community mean height, while variations in aboveground biomass were driven by community type and the height of dominant species. These findings indicate that if habitat drying of these herbaceous wetlands in this region continues, then two Carex marshes would be replaced gradually by C. angustifolia wet meadow in the near future. This will lead to a reduction in biodiversity and an increase in productivity and carbon budget. Meanwhile, functional traits must be considered, and should be a focus of attention in future studies on the species diversity and ecosystem function in this region. PMID:27097325

Annual report. (Air quality criteria and plants as biological indicators)

Energy Technology Data Exchange (ETDEWEB)

1969-01-01

Studies have been carried out to derive air quality criteria as the basis for establishing emission limits. Experiments have also been carried out on the resistance of plant species which are important to the economy and public health. Among the specific avenues of investigation have been: the determination of phytotoxic hydrogen fluoride concentrations; studies on the resistance behavior of cultivated plants; fluorine enrichment in plant organs as a function of exposure height and wind speed; development and use of biological methods for detecting atmospheric impurities; detection of sulfur dioxide effects on plants; the use of transplanted lichens as air pollution indicators; grass cultures as indicators of fluorine pollution; biological accumulation of fluorine as a function of HF concentration in air; and the determination of lead and zinc levels in plants. 5 figures, 4 tables.

3. General principles of assessing seismic resistance of technological equipment of nuclear power plants

International Nuclear Information System (INIS)

1983-01-01

The evaluation of the seismic resistance of technological equipment is performed by computation, experimental trial, possibly by combining both methods. Existing and prepared standards in the field of seismic resistance of nuclear power plants are mentioned. Accelerograms and response spectra of design-basis earhtquake and maximum credible earthquake serve as the basic data for evaluating seismic resistance. The nuclear power plant in Mochovce will be the first Czechoslovak nuclear power plant with so-called partially seismic design. The problem of dynamic interaction of technological equipment and nuclear power plant systems with a bearing structure is discussed. (E.F.)

Lodging resistant pea line derived after mutagenic treatment

International Nuclear Information System (INIS)

Naidenova, N.; Vassilevska-Ivanova, R.

2006-01-01

Line 1/502 is a new lodging resistant pea ( Pisum sativum L.) developed for the Bulgarian field pea industry. This line is a direct chlorophyll mutant, which originates after treatment of the initial line, cultivar Auralia, with 150 Gy 60 Co γ - radiation. In regional evaluation trials conducted in Sofia over seven successive seasons 1/502 has revealed improved standing ability that most probably is a result from modification of the architecture of the plants appearing in reduction of plant height. The agronomic and morphological characteristics of the mutant line were reported. The upright plant habit and resistance to lodging is especially beneficial for production of high quality peas because pods are held above the soil surface during crop development and during maturity which aids in keeping the peas clean and free of pathogens that can cause discoloration and rotting. (authors)

Host-plant-mediated effects of Nadefensin on herbivore and pathogen resistance in Nicotiana attenuata

Directory of Open Access Journals (Sweden)

Baldwin Ian T

2008-10-01

Full Text Available Abstract Background The adage from Shakespeare, "troubles, not as single spies, but in battalions come," holds true for Nicotiana attenuata, which is commonly attacked by both pathogens (Pseudomonas spp. and herbivores (Manduca sexta in its native habitats. Defense responses targeted against the pathogens can directly or indirectly influence the responses against the herbivores. Nadefensin is an effective induced defense gene against the bacterial pathogen Pseudomonas syringae pv tomato (PST DC3000, which is also elicited by attack from M. sexta larvae, but whether this defense protein influences M. sexta's growth and whether M. sexta-induced Nadefensin directly or indirectly influences PST DC3000 resistance are unknown. Results M. sexta larvae consumed less on WT and on Nadefensin-silenced N. attenuata plants that had previously been infected with PST DC3000 than on uninfected plants. WT plants infected with PST DC3000 showed enhanced resistance to PST DC3000 and decreased leaf consumption by M. sexta larvae, but larval mass gain was unaffected. PST DC3000-infected Nadefensin-silenced plants were less resistant to subsequent PST DC3000 challenge, and on these plants, M. sexta larvae consumed less and gained less mass. WT and Nadefensin-silenced plants previously damaged by M. sexta larvae were better able to resist subsequent PST DC3000 challenges than were undamaged plants. Conclusion These results demonstrate that Na-defensin directly mediates defense against PST DC3000 and indirectly against M. sexta in N. attenuata. In plants that were previously infected with PST DC3000, the altered leaf chemistry in PST DC3000-resistant WT plants and PST DC3000-susceptible Nadefensin-silenced plants differentially reduced M. sexta's leaf consumption and mass gain. In plants that were previously damaged by M. sexta, the combined effect of the altered host plant chemistry and a broad spectrum of anti-herbivore induced metabolomic responses was more

Transgenerational Effects Alter Plant Defense and Resistance in Nature

Science.gov (United States)

Colicchio, Jack

2017-01-01

Trichomes, or leaf hairs, are epidermal extensions that take a variety of forms and perform many functions in plants, including herbivore defense. In this study, I document genetically determined variation, within-generation plasticity, and a direct role of trichomes in herbivore defense for Mimulus guttatus. After establishing the relationship between trichomes and herbivory, I test for transgenerational effects of wounding on trichome density and herbivore resistance. Patterns of inter-annual variation in herbivore density and the high cost of plant defense makes plant-herbivore interactions a system in which transgenerational phenotypic plasticity (TPP) is apt to evolve. Here, I demonstrate that parental damage alters offspring trichome density and herbivore resistance in nature. Moreover, this response varies between populations. This is among the first studies to demonstrate that TPP contributes to variation in nature, and also suggests that selection can modify TPP in response to local conditions. PMID:28102915

Method for increasing the resistance of a plant or a part thereof to a pathogen, method for screening the resistance of a plant or part thereof to a pathogen, and use thereof

OpenAIRE

Wit, de, P.; Stergiopoulos, I.; Kema, G.H.J.

2011-01-01

(EN)The present invention relates to the field of plant biotechnology. More in particular, the present invention relates to methods for increasing the resistance of a plant or part thereof that is susceptible to infection with a pathogen comprising an ortholog of the Avr4 protein of Cladosporium fulvum, wherein said plant is not a tomato or tobacco plant. The invention also relates to methods for screening the resistance of a plant or a part thereof to at least one pathogen, wherein said path...

Bio-based resistance inducers for sustainable plant protection against pathogens

Czech Academy of Sciences Publication Activity Database

Burketová, Lenka; Trdá, Lucie; Ott, P.G.; Valentová, O.

2015-01-01

Roč. 33, č. 6 (2015), s. 994-1004 ISSN 0734-9750 R&D Projects: GA MŠk(CZ) LD14056 Institutional support: RVO:61389030 Keywords : Induced resistance * Elicitor * Chitosan Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 9.848, year: 2015

The biochar effect: plant resistance to biotic stresses

Directory of Open Access Journals (Sweden)

YIGAL ELAD

2012-01-01

Full Text Available Biochar (charcoal is the solid co-product of pyrolysis, the thermal degradation of biomass in the absence of oxygen. Pyrolysis also yields gaseous and liquid biofuel products. There is a growing interest worldwide in the pyrolysis platform, for at least four reasons: (i pyrolysis can be a source of renewable biofuels; (ii many biomass waste materials can be treated by pyrolysis and thus converted into a fuel resource; (iii long-term sequestration of carbon dioxide which originated in the atmosphere may result from adding biochar to soil; and (iv biochar soil amendment contributes to improved soil fertility and crop productivity. Currently, however, very little biochar is utilized in agriculture, in part because its agronomic value in terms of crop response and soil health benefits have yet to be quantified, and because the mechanisms by which it improves soil fertility are poorly understood. The positive effects of biochar on crop productivity under conditions of extensive agriculture are frequently attributed to direct effects of biochar-supplied nutrients and to several other indirect effects, including increased water and nutrient retention, improvements in soil pH, increased soil cation exchange capacity, effects on P and S transformations and turnover, neutralization of phytotoxic compounds in the soil, improved soil physical properties, promotion of mycorrhizal fungi, and alteration of soil microbial populations and functions. Yet, the biochar effect is also evident under conditions of intensive production where many of these parameters are not limited. Biochar addition to soil alters microbial populations in the rhizosphere, albeit via mechanisms not yet understood, and may cause a shift towards beneficial microorganism populations that promote plant growth and resistance to biotic stresses. In addition to some scant evidence for biochar-induced plant protection against soilborne diseases, the induction of systemic resistance towards

Amazonian plant crude extract screening for activity against multidrug-resistant bacteria.

Science.gov (United States)

Correia, A F; Segovia, J F O; Gonçalves, M C A; de Oliveira, V L; Silveira, D; Carvalho, J C T; Kanzaki, L I B

2008-01-01

Antimicrobial resistance is a subject of great concern in public health and also in the designing of strategies for current therapeutic protocols all over the world. New drugs, including those necessary for a reserve armamentarium and exhibiting less side effects deserve special attention. In rural areas, particularly in Brazil, a huge number of natural products, in different artisanal preparations, mainly from plants, have been used by traditional populations to cure diseases. Despite some of these plants have been studied, many of them are awaiting to have their compounds chemically characterized and investigated their pharmacodynamics properties. Further, as well known, the environment plays a crucial role in the metabolism of these plants, yielding different and varied molecular complexes depending on the period of collection, climate conditions, kind of soil and also the plant speciation. In this report, ethanol crude extract of 10 different botanical specimens from the Amazon region of Brazil, in the Amapa State, were screened for antibacterial activity of 7 clinical resistant microorganisms utilizing as control ATCC bacterial species by the Kirby-Bauer method. Plant extracts of Geissospermum argenteum, Uncaria guianensis, Brosimum acutifolium, Copaifera reticulate, Licania macrophylla, Ptycopetalum olacoides and Dalbergia subcymosa yielded activity against Staphylococcus aureus and Pseudomonas aeruginosa, both multidrug resistant, and Staphylococcus aureus ATCC strain.

Transgenerational effects alter plant defence and resistance in nature.

Science.gov (United States)

Colicchio, J

2017-04-01

Trichomes, or leaf hairs, are epidermal extensions that take a variety of forms and perform many functions in plants, including herbivore defence. In this study, I document genetically determined variation, within-generation plasticity, and a direct role of trichomes in herbivore defence for Mimulus guttatus. After establishing the relationship between trichomes and herbivory, I test for transgenerational effects of wounding on trichome density and herbivore resistance. Patterns of interannual variation in herbivore density and the high cost of plant defence makes plant-herbivore interactions a system in which transgenerational phenotypic plasticity (TPP) is apt to evolve. Here, I demonstrate that parental damage alters offspring trichome density and herbivore resistance in nature. Moreover, this response varies between populations. This is among the first studies to demonstrate that TPP contributes to variation in nature, and also suggests that selection can modify TPP in response to local conditions. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Enhanced Methanol Production in Plants Provides Broad Spectrum Insect Resistance

Science.gov (United States)

Dixit, Sameer; Upadhyay, Santosh Kumar; Singh, Harpal; Sidhu, Om Prakash; Verma, Praveen Chandra; K, Chandrashekar

2013-01-01

Plants naturally emit methanol as volatile organic compound. Methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. In the present study, we demonstrated that the over-expression of pectin methylesterase, derived from Arabidopsis thaliana and Aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. Methanol content in the leaves of transgenic plants was measured using proton nuclear spectroscopy (1H NMR) and spectra showed up to 16 fold higher methanol as compared to control wild type (WT) plants. A maximum of 100 and 85% mortality in chewing insects Helicoverpa armigera and Spodoptera litura larvae was observed, respectively when fed on transgenic plants leaves. The surviving larvae showed less feeding, severe growth retardation and could not develop into pupae. In-planta bioassay on transgenic lines showed up to 99 and 75% reduction in the population multiplication of plant sap sucking pests Myzus persicae (aphid) and Bemisia tabaci (whitefly), respectively. Most of the phenotypic characters of transgenic plants were similar to WT plants. Confocal microscopy showed no deformities in cellular integrity, structure and density of stomata and trichomes of transgenic plants compared to WT. Pollen germination and tube formation was also not affected in transgenic plants. Cell wall enzyme transcript levels were comparable with WT. This study demonstrated for the first time that methanol emission can be utilized for imparting broad range insect resistance in plants. PMID:24223989

Enhanced methanol production in plants provides broad spectrum insect resistance.

Directory of Open Access Journals (Sweden)

Sameer Dixit

Full Text Available Plants naturally emit methanol as volatile organic compound. Methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. In the present study, we demonstrated that the over-expression of pectin methylesterase, derived from Arabidopsis thaliana and Aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. Methanol content in the leaves of transgenic plants was measured using proton nuclear spectroscopy (1H NMR and spectra showed up to 16 fold higher methanol as compared to control wild type (WT plants. A maximum of 100 and 85% mortality in chewing insects Helicoverpa armigera and Spodoptera litura larvae was observed, respectively when fed on transgenic plants leaves. The surviving larvae showed less feeding, severe growth retardation and could not develop into pupae. In-planta bioassay on transgenic lines showed up to 99 and 75% reduction in the population multiplication of plant sap sucking pests Myzus persicae (aphid and Bemisia tabaci (whitefly, respectively. Most of the phenotypic characters of transgenic plants were similar to WT plants. Confocal microscopy showed no deformities in cellular integrity, structure and density of stomata and trichomes of transgenic plants compared to WT. Pollen germination and tube formation was also not affected in transgenic plants. Cell wall enzyme transcript levels were comparable with WT. This study demonstrated for the first time that methanol emission can be utilized for imparting broad range insect resistance in plants.

Heterosis for yield and its components in bread wheat crosses among powdery mildew resistant and susceptible genotypes

International Nuclear Information System (INIS)

Ilker, E.; Tonk, F.A.; Tosun, M.

2010-01-01

The objective of this research was to investigate heterotic effects between five powdery mildew resistant wheat lines derived from CIMMYT and three susceptible commercial wheat varieties growing in Turkey and to determine mode of gene actions of the parents for yield characters in F1 generation. All 15 F1 crosses and their parents were planted in randomized complete block design in three replications. Measurements were done for plant height, pike length, spike let and kernel number per spike, grain weight per spike and 1000-kernel weight. Promising findings of the crosses 72 x Golia, 70 x Golia, 70 x Basribey, 48 x Basribey, 48 x Atilla-12 and 72 x Atilla12 were obtained to breed new varieties or pure lines having shorter plant height and taller spike length, more number of spike let and kernel per spike, besides higher grain yield than their mid or better parents to improve powdery mildew resistant varieties. (author)

Plant hygiene and resistance breeding as plant protection and cultivation methods in areas where emission levels are high

Energy Technology Data Exchange (ETDEWEB)

Berge, H

1967-01-01

If plants are to be used for human or animal consumption, phyto-hygiene is of great importance wherever there are significant amounts of emissions. Breeding resistant plants for technical use is important in regions where atmospheric influences such as gas, steam and dust are encountered. Besides the climatic, orographic, edaphic and chronologic conditions, biologic, chemic and physico-mechanic factors influence the incompatible conceptions of phyto-hygiene and resistance breeding. Several examples are quoted.

In Vitro Antibacterial and Antibiotic Resistance Modifying Effect of Bioactive Plant Extracts on Methicillin-Resistant Staphylococcus epidermidis

Directory of Open Access Journals (Sweden)

Romana Chovanová

2013-01-01

Full Text Available The crude extracts of plants from Asteraceae and Lamiaceae family and essential oils from Salvia officinalis and Salvia sclarea were studied for their antibacterial as well as antibiotic resistance modifying activity. Using disc diffusion and broth microdilution assays we determined higher antibacterial effect of three Salvia spp. and by evaluating the leakage of 260 nm absorbing material we detected effect of extracts and, namely, of essential oils on the disruption of cytoplasmic membrane. The evaluation of in vitro interactions between plant extracts and oxacillin described in terms of fractional inhibitory concentration (FIC indices revealed synergistic or additive effects of plant extracts and clearly synergistic effects of essential oil from Salvia officinalis with oxacillin in methicillin-resistant Staphylococcus epidermidis.

A novel gene of Kalanchoe daigremontiana confers plant drought resistance.

Science.gov (United States)

Wang, Li; Zhu, Chen; Jin, Lin; Xiao, Aihua; Duan, Jie; Ma, Luyi

2018-02-07

Kalanchoe (K.) daigremontiana is important for studying asexual reproduction under different environmental conditions. Here, we describe a novel KdNOVEL41 (KdN41) gene that may confer drought resistance and could thereby affect K. daigremontiana development. The detected subcellular localization of a KdN41/Yellow Fluorescent Protein (YFP) fusion protein was in the nucleus and cell membrane. Drought, salt, and heat stress treatment in tobacco plants containing the KdN41 gene promoter driving β-glucuronidase (GUS) gene transcription revealed that only drought stress triggered strong GUS staining in the vascular tissues. Overexpression (OE) of the KdN41 gene conferred improved drought resistance in tobacco plants compared to wild-type and transformed with empty vector plants by inducing higher antioxidant enzyme activities, decreasing cell membrane damage, increasing abscisic acid (ABA) content, causing reinforced drought resistance related gene expression profiles. The 3,3'-diaminobenzidine (DAB) and nitroblue tetrazolium (NBT) staining results also showed less relative oxygen species (ROS) content in KdN41-overexpressing tobacco leaf during drought stress. Surprisingly, by re-watering after drought stress, KdN41-overexpressing tobacco showed earlier flowering. Overall, the KdN41 gene plays roles in ROS scavenging and osmotic damage reduction to improve tobacco drought resistance, which may increase our understanding of the molecular network involved in developmental manipulation under drought stress in K. daigremontiana.

Signal perception, transduction, and response in gravity resistance. Another graviresponse in plants

Science.gov (United States)

Hoson, T.; Saito, Y.; Soga, K.; Wakabayashi, K.

Resistance to the gravitational force is a serious problem that plants have had to solve to survive on land. Mechanical resistance to the pull of gravity is thus a principal graviresponse in plants, comparable to gravitropism. Nevertheless, only limited information has been obtained for this gravity response. We have examined the mechanism of gravity-induced mechanical resistance using hypergravity conditions produced by centrifugation. As a result, we have clarified the outline of the sequence of events leading to the development of mechanical resistance. The gravity signal may be perceived by mechanoreceptors (mechanosensitive ion channels) on the plasma membrane and it appears that amyloplast sedimentation in statocytes is not involved. Transformation and transduction of the perceived signal may be mediated by the structural or physiological continuum of microtubule-cell membrane-cell wall. As the final step in the development of mechanical resistance, plants construct a tough body by increasing cell wall rigidity. The increase in cell wall rigidity is brought about by modification of the metabolism of certain wall constituents and modification of the cell wall environment, especially pH. We need to clarify the details of each step by future space and ground-based experiments.

Transcriptional plant responses critical for resistance towards necrotrophic pathogens

Directory of Open Access Journals (Sweden)

Rainer P. Birkenbihl

2011-11-01

Full Text Available Plant defenses aimed at necrotrophic pathogens appear to be genetically complex. Despite the apparent lack of a specific recognition of such necrotrophs by products of major R genes, biochemical, molecular, and genetic studies, in particular using the model plant Arabidopsis, have uncovered numerous host components critical for the outcome of such interactions. Although the JA signaling pathway plays a central role in plant defense towards necrotrophs additional signaling pathways contribute to the plant response network. Transcriptional reprogramming is a vital part of the host defense machinery and several key regulators have recently been identified. Some of these transcription factors positively affect plant resistance whereas others play a role in enhancing host susceptibility towards these phytopathogens.

Race-Specific Adult-Plant Resistance in Winter Wheat to Stripe Rust and Characterization of Pathogen Virulence Patterns.

Science.gov (United States)

Milus, Eugene A; Moon, David E; Lee, Kevin D; Mason, R Esten

2015-08-01

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is an important disease of wheat in the Great Plains and southeastern United States. Growing resistant cultivars is the preferred means for managing stripe rust, but new virulence in the pathogen population overcomes some of the resistance. The objectives of this study were to characterize the stripe rust resistance in contemporary soft and hard red winter wheat cultivars, to characterize the virulence of P. striiformis f. sp. tritici isolates based on the resistances found in the cultivars, and to determine wheat breeders' perceptions on the importance and methods for achieving stripe rust resistance. Seedlings of cultivars were susceptible to recent isolates, indicating they lacked effective all-stage resistance. However, adult-plants were resistant or susceptible depending on the isolate, indicating they had race-specific adult-plant resistance. Using isolates collected from 1990 to 2013, six major virulence patterns were identified on adult plants of twelve cultivars that were selected as adult-plant differentials. Race-specific adult-plant resistance appears to be the only effective type of resistance protecting wheat from stripe rust in eastern United States. Among wheat breeders, the importance of incorporating stripe rust resistance into cultivars ranged from high to low depending on the frequency of epidemics in their region, and most sources of stripe rust resistance were either unknown or already overcome by virulence in the pathogen population. Breeders with a high priority for stripe rust resistance made most of their selections based on adult-plant reactions in the field, whereas breeders with a low priority for resistance based selections on molecular markers for major all-stage resistance genes.

Gravity resistance, another graviresponse in plants - role of microtubule-membrane-cell wall continuum

Science.gov (United States)

Hoson, T.; Saito, Y.; Usui, S.; Soga, K.; Wakabayashi, K.

Resistance to the gravitational force has been a serious problem for plants to survive on land, after they first went ashore more than 400 million years ago. Thus, gravity resistance is the principal graviresponse in plants comparable to gravitropism. Nevertheless, only limited information has been obtained for this second gravity response. We have examined the mechanism of gravity resistance using hypergravity conditions produced by centrifugation. The results led a hypothesis on the mechanism of plant resistance to the gravitational force that the plant constructs a tough body by increasing the cell wall rigidity, which are brought about by modification of the cell wall metabolism and cell wall environment, especially pH. The hypothesis was further supported by space experiments during the Space Shuttle STS-95 mission. On the other hand, we have shown that gravity signal may be perceived by mechanoreceptors (mechanosensitive ion channels) on the plasma membrane and amyloplast sedimentation in statocytes is not involved in gravity resistance. Moreover, hypergravity treatment increased the expression levels of genes encoding alpha-tubulin, a component of microtubules and 3-hydroxy-3-methylglutaryl-Coenzyme A reductase (HMGR), which catalyzes a reaction producing mevalonic acid, a key precursor of terpenoids such as membrane sterols. The expression of HMGR and alpha- and beta-tubulin genes increased within several hours after hypergravity treatment, depending on the magnitude of gravity. The determination of levels of gene products as well as the analysis with knockout mutants of these genes by T-DNA insertions in Arabidopsis supports the involvement of both membrane sterols and microtubules in gravity resistance. These results suggest that structural or physiological continuum of microtubule-cell membrane-cell wall is responsible for plant resistance to the gravitational force.

Induction of Systemic Resistance against Insect Herbivores in Plants by Beneficial Soil Microbes

Directory of Open Access Journals (Sweden)

Md. Harun-Or Rashid

2017-10-01

Full Text Available Soil microorganisms with growth-promoting activities in plants, including rhizobacteria and rhizofungi, can improve plant health in a variety of different ways. These beneficial microbes may confer broad-spectrum resistance to insect herbivores. Here, we provide evidence that beneficial microbes modulate plant defenses against insect herbivores. Beneficial soil microorganisms can regulate hormone signaling including the jasmonic acid, ethylene and salicylic acid pathways, thereby leading to gene expression, biosynthesis of secondary metabolites, plant defensive proteins and different enzymes and volatile compounds, that may induce defenses against leaf-chewing as well as phloem-feeding insects. In this review, we discuss how beneficial microbes trigger induced systemic resistance against insects by promoting plant growth and highlight changes in plant molecular mechanisms and biochemical profiles.

Pokeweed Antiviral Protein: Its Cytotoxicity Mechanism and Applications in Plant Disease Resistance

Directory of Open Access Journals (Sweden)

Rong Di

2015-03-01

Full Text Available Pokeweed antiviral protein (PAP is a 29 kDa type I ribosome inactivating protein (RIP found in pokeweed plants. Pokeweed produces different forms of PAP. This review focuses on the spring form of PAP isolated from Phytolacca americana leaves. PAP exerts its cytotoxicity by removing a specific adenine from the α-sarcin/ricin loop of the large ribosomal RNA. Besides depurination of the rRNA, PAP has additional activities that contribute to its cytotoxicity. The mechanism of PAP cytotoxicity is summarized based on evidence from the analysis of transgenic plants and the yeast model system. PAP was initially found to be anti-viral when it was co-inoculated with plant viruses onto plants. Transgenic plants expressing PAP and non-toxic PAP mutants have displayed broad-spectrum resistance to both viral and fungal infection. The mechanism of PAP-induced disease resistance in transgenic plants is summarized.

Very low Schottky barrier height at carbon nanotube and silicon carbide interface

Energy Technology Data Exchange (ETDEWEB)

Inaba, Masafumi, E-mail: inaba-ma@ruri.waseda.jp; Suzuki, Kazuma; Shibuya, Megumi; Lee, Chih-Yu [Faculty of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555 (Japan); Masuda, Yoshiho; Tomatsu, Naoya; Norimatsu, Wataru; Kusunoki, Michiko [EcoTopia Science Institute, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603 (Japan); Hiraiwa, Atsushi [Institute for Nanoscience and Nanotechnology, Waseda University, 513 Waseda-tsurumaki, Shinjuku, Tokyo 162-0041 (Japan); Kawarada, Hiroshi [Faculty of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555 (Japan); Institute for Nanoscience and Nanotechnology, Waseda University, 513 Waseda-tsurumaki, Shinjuku, Tokyo 162-0041 (Japan); The Kagami Memorial Laboratory for Materials Science and Technology, Waseda University, 2-8-26 Nishiwaseda, Shinjuku, Tokyo 169-0051 (Japan)

2015-03-23

Electrical contacts to silicon carbide with low contact resistivity and high current durability are crucial for future SiC power devices, especially miniaturized vertical-type devices. A carbon nanotube (CNT) forest formed by silicon carbide (SiC) decomposition is a densely packed forest, and is ideal for use as a heat-dissipative ohmic contact in SiC power transistors. The contact resistivity and Schottky barrier height in a Ti/CNT/SiC system with various SiC dopant concentrations were evaluated in this study. Contact resistivity was evaluated in relation to contact area. The Schottky barrier height was calculated from the contact resistivity. As a result, the Ti/CNT/SiC contact resistivity at a dopant concentration of 3 × 10{sup 18 }cm{sup −3} was estimated to be ∼1.3 × 10{sup −4} Ω cm{sup 2} and the Schottky barrier height of the CNT/SiC contact was in the range of 0.40–0.45 eV. The resistivity is relatively low for SiC contacts, showing that CNTs have the potential to be a good ohmic contact material for SiC power electronic devices.

Antibacterial activity of combined medicinal plants extract against multiple drug resistant strains

Directory of Open Access Journals (Sweden)

Rafiqul Islam

2015-06-01

Full Text Available Objective: To find out the combined antibacterial efficacy of Aegle marmelos, Aphanamixis polystachya, Cuscuta reflexa and Aesclynomene indica against bacterial pathogens. Methods: Antibacterial potency of combined plant extracts has been tested against Bacillus subtilis IFO 3026, Sarcina lutea IFO 3232, Xanthomonas campestris IAM 1671, Escherichia coli IFO 3007, Klebsiella pneumoniae ATTC 10031, Proteus vulgaris MTCC 321 and Pseudomonas denitrificans KACC 32026 by disc diffusion assay. Commercially available standard antibiotic discs were also used to find out antibiotic resistance pattern of test organisms. Results: Among the test organisms, Escherichia coli, Proteus vulgaris, Klebsiella pneumoniae and Proteus denitrificans showed resistance against multiple commercially available antibiotics. On the other hand, these multiple drug resistant organisms showed susceptibility against combined plant extracts. Conclusions: These combined plants extracts showed synergistic antibacterial activity and could lead to new antibacterial drug designing.

Bleomycin resistance : a new dominant selectable marker for plant cell transformation

NARCIS (Netherlands)

Hille, Jacques; Verheggen, Frank; Roelvink, Peter; Franssen, Henk; Kammen, Ab van; Zabel, Pim

1986-01-01

Plant cells are sensitive to the antibiotic bleomycin, a DNA damaging glycopeptide. A bleomycin resistance determinant, located on transposon Tn5 and functional in bacteria, has been cloned in a plant expression vector and introduced into Nicotiana plumbaginifolia using Agrobacterium tumefaciens.

Physiological plant investigations for the purpose of growing smoke resistant conifers

Energy Technology Data Exchange (ETDEWEB)

Polster, H; Bortitz, S; Vogl, M

1965-01-01

Spruce and pine are the main commercial wood varieties used in East Germany. These are also the most sensitive to smoke. Usually replacement of the damaged trees is necessary. The Department of Smoke Research of the Institute for Plant Chemistry of the Dresden Institute of Technology has been able to develop conifers resistant to SO2. In order to select smoke resistant trees for breeding, the Institute for Forestry and Plant Physiology of the Institute of Forestry Breeding in Graupa, East Germany has developed a rapid selection test. It is based on subjecting a small branch to doses of SO2. A method of breeding smoke resistant conifers is given in detail. It takes approximately ten years to produce the seeds.

Induction of resistance of corn plants to Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) by application of silicon and gibberellic acid.

Science.gov (United States)

Alvarenga, R; Moraes, J C; Auad, A M; Coelho, M; Nascimento, A M

2017-08-01

The aim of this study was to evaluate the effects of silicon application and administration of the phytohormone gibberellic acid on resistance of the corn plants to the fall armyworm (FAW), Spodoptera frugiperda, and their vegetative characteristics. We evaluated larval and pupal duration, survival and biomass, and adult longevity, malformation and fecundity of S. frugiperda after feeding on plant matter treated with silicon and/or gibberellic acid. The feeding preference of FAW first-instar larvae, the total leaf area consumed by the insects, and the vegetative parameters of corn plants were also evaluated. No significant differences were observed in the measured parameters of larval and pupal stages of S. frugiperda in response to silicon or gibberellic acid. In adult stage insects, the number of eggs per female was significantly reduced in insects derived from larvae fed plants treated with silicon or gibberellic acid. In a non-preference test, 48 h after release, caterpillars preferred control untreated plants and consumed less matter from plants that had received hormonal treatment (gibberellic acid). Gibberellic acid also altered the vegetative characteristics of plants, by increasing their height, shoot fresh and dry mass, and silicon content. We conclude that gibberellic acid can alter the vegetative characteristics and silicon uptake of corn plants, leading to a reduction in their consumption by S. frugiperda larvae and a decrease in female insect oviposition.

Review: Potential biotechnological assets related to plant immunity modulation applicable in engineering disease-resistant crops.

Science.gov (United States)

Silva, Marilia Santos; Arraes, Fabrício Barbosa Monteiro; Campos, Magnólia de Araújo; Grossi-de-Sa, Maira; Fernandez, Diana; Cândido, Elizabete de Souza; Cardoso, Marlon Henrique; Franco, Octávio Luiz; Grossi-de-Sa, Maria Fátima

2018-05-01

This review emphasizes the biotechnological potential of molecules implicated in the different layers of plant immunity, including, pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI), effector-triggered susceptibility (ETS), and effector-triggered immunity (ETI) that can be applied in the development of disease-resistant genetically modified (GM) plants. These biomolecules are produced by pathogens (viruses, bacteria, fungi, oomycetes) or plants during their mutual interactions. Biomolecules involved in the first layers of plant immunity, PTI and ETS, include inhibitors of pathogen cell-wall-degrading enzymes (CWDEs), plant pattern recognition receptors (PRRs) and susceptibility (S) proteins, while the ETI-related biomolecules include plant resistance (R) proteins. The biomolecules involved in plant defense PTI/ETI responses described herein also include antimicrobial peptides (AMPs), pathogenesis-related (PR) proteins and ribosome-inhibiting proteins (RIPs), as well as enzymes involved in plant defensive secondary metabolite biosynthesis (phytoanticipins and phytoalexins). Moreover, the regulation of immunity by RNA interference (RNAi) in GM disease-resistant plants is also considered. Therefore, the present review does not cover all the classes of biomolecules involved in plant innate immunity that may be applied in the development of disease-resistant GM crops but instead highlights the most common strategies in the literature, as well as their advantages and disadvantages. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Antibiotic Resistant Bacteria And Their Associated Resistance Genes in a Conventional Municipal Wastewater Treatment Plant

KAUST Repository

Aljassim, Nada I.

2013-12-01

With water scarcity as a pressing issue in Saudi Arabia and other Middle Eastern countries, the treatment and reuse of municipal wastewater is increasingly being used as an alternative water source to supplement country water needs. Standards are in place to ensure a safe treated wastewater quality, however they do not regulate pathogenic bacteria and emerging contaminants. Information is lacking on the levels of risk to public health associated with these factors, the efficiency of conventional treatment strategies in removing them, and on wastewater treatment in Saudi Arabia in general. In this study, a municipal wastewater treatment plant in Saudi Arabia is investigated to assess the efficiency of conventional treatment in meeting regulations and removing pathogens and emerging contaminants. The study found pathogenic bacterial genera, antibiotic resistance genes and antibiotic resistant bacteria, many of which were multi-resistant in plant discharges. It was found that although the treatments are able to meet traditional quality guidelines, there remains a risk from the discussed contaminants with wastewater reuse. A deeper understanding of this risk, and suggestions for more thorough guidelines and monitoring are needed.

In vitro screening methods for assessing plant disease resistance

International Nuclear Information System (INIS)

Lebeda, A.; Svabova, L.

2010-01-01

A combination of biotechnological and phytopathological techniques provides an alternative approach to classical resistance breeding methods. Such techniques have been increasingly used since the 1980s, in parallel with the progress in plant biotechnology. In the approach of resistance screening and selection in vitro, both experimental objects, i.e., the plant and the pathogen, must first be transferred to in vitro conditions, and finally, the plant material must be transferred back to in vivo conditions and adapted to the outside settings. Specific attention must be paid to the methods of pathogen preparation for use in screening and selection in vitro. The selection agents are classified according to their origin, the methods of preparation, nature and content of active substances, and effective utilisation for screening or selection in vitro. Basic principles and methodological aspects of the in vitro work (explant cultures, sources of in vitro variability, screening and selection methods, types of selection agents) as well as examples of practical applications in the breeding of different crops are critically reviewed in this chapter. (author)

A fungal root symbiont modifies plant resistance to an insect herbivore.

Science.gov (United States)

Borowicz, Victoria A

1997-11-01

Vesicular-arbuscular mycorrhizal (VAM) fungi are common root-colonizing symbionts that affect nutrient uptake by plants and can alter plant susceptibility to herbivores. I conducted a factorial experiment to test the hypotheses that colonization by VAM fungi (1) improves soybean (Glycine max) tolerance to grazing by folivorous Mexican bean beetle (Epilachna varivestis), and (2) indirectly affects herbivores by increasing host resistance. Soybean seedlings were inoculated with the VAM fungus Glomus etunicatum or VAM-free filtrate and fertilized with high-[P] or low-[P] fertilizer. After plants had grown for 7 weeks first-instar beetle larvae were placed on bagged leaves. Growth of soybean was little affected by grazing larvae, and no effects of treatments on tolerance of soybeans to herbivores were evident. Colonization by VAM fungus doubled the size of phosphorus-stressed plants but these plants were still half the size of plants given adequate phosphorus. High-[P] fertilizer increased levels of phosphorus and soluble carbohydrates, and decreased levels of soluble proteins in leaves of grazed plants. Colonization of grazed plants by VAM fungus had no significant effect on plant soluble carbohydrates, but increased concentration of phosphorus and decreased levels of proteins in phosphorus-stressed plants to concentrations similar to those of plants given adequate phosphorus. Mexican bean beetle mass at pupation, pupation rate, and survival to eclosion were greatest for beetles reared on phosphorus-stressed, VAM-colonized plants, refuting the hypothesis that VAM colonization improves host plant resistance. VAM colonization indirectly affected performance of Mexician bean beetle larvae by improving growth and nutrition of the host plant.

Insights into Resistance to Fe Deficiency Stress from a Comparative Study of In Vitro-Selected Novel Fe-Efficient and Fe-Inefficient Potato Plants

Directory of Open Access Journals (Sweden)

Georgina A. Boamponsem

2017-09-01

Full Text Available Iron (Fe deficiency induces chlorosis (IDC in plants and can result in reduced plant productivity. Therefore, development of Fe-efficient plants is of great interest. To gain a better understanding of the physiology of Fe-efficient plants, putative novel plant variants were regenerated from potato (Solanum tubersosum L. var. ‘Iwa’ callus cultures selected under Fe deficient or low Fe supply (0–5 μM Fe. Based on visual chlorosis rating (VCR, 23% of callus-derived regenerants were classified as Fe-efficient (EF and 77% as Fe-inefficient (IFN plant lines when they were grown under Fe deficiency conditions. Stem height was found to be highly correlated with internodal distance, leaf and root lengths in the EF plant lines grown under Fe deficiency conditions. In addition, compared to the IFN plant lines and control parental biotype, the EF plants including the lines named A1, B2, and B9, exhibited enhanced formation of lateral roots and root hairs as well as increased expression of ferritin (fer3 in the leaf and iron-regulated transporter (irt1 in the root. These morphological adaptations and changes in expression the fer3 and irt1 genes of the selected EF potato lines suggest that they are associated with resistance to low Fe supply stress.

Meaningful traits for grouping plant species across arid ecosystems.

Science.gov (United States)

Bär Lamas, Marlene Ivonne; Carrera, A L; Bertiller, M B

2016-05-01

Grouping species may provide some degree of simplification to understand the ecological function of plants on key ecosystem processes. We asked whether groups of plant species based on morpho-chemical traits associated with plant persistence and stress/disturbance resistance reflect dominant plant growth forms in arid ecosystems. We selected twelve sites across an aridity gradient in northern Patagonia. At each site, we identified modal size plants of each dominant species and assessed specific leaf area (SLA), plant height, seed mass, N and soluble phenol concentration in green and senesced leaves at each plant. Plant species were grouped according with plant growth forms (perennial grasses, evergreen shrubs and deciduous shrubs) and plant morphological and/or chemical traits using cluster analysis. We calculated mean values of each plant trait for each species group and plant growth form. Plant growth forms significantly differed among them in most of the morpho-chemical traits. Evergreen shrubs were tall plants with the highest seed mass and soluble phenols in leaves, deciduous shrubs were also tall plants with high SLA and the highest N in leaves, and perennial grasses were short plants with high SLA and low concentration of N and soluble phenols in leaves. Grouping species by the combination of morpho-chemical traits yielded 4 groups in which species from one growth form prevailed. These species groups differed in soluble phenol concentration in senesced leaves and plant height. These traits were highly correlated. We concluded that (1) plant height is a relevant synthetic variable, (2) growth forms adequately summarize ecological strategies of species in arid ecosystems, and (3) the inclusion of plant morphological and chemical traits related to defenses against environmental stresses and herbivory enhanced the potential of species grouping, particularly within shrubby growth forms.

Comparison of ALS functionality and plant growth in ALS-inhibitor susceptible and resistant Myosoton aquaticum L.

Science.gov (United States)

Liu, Weitang; Bai, Shuang; Jia, Sisi; Guo, Wenlei; Zhang, Lele; Li, Wei; Wang, Jinxin

2017-10-01

Herbicide target-site resistance mutations may cause pleiotropic effects on plant ecology and physiology. The effect of several known (Pro197Ser, Pro197Leu Pro197Ala, and Pro197Glu) target-site resistance mutations of the ALS gene on both ALS functionality and plant vegetative growth of weed Myosoton aquaticum L. (water chickweed) have been investigated here. The enzyme kinetics of ALS from four purified water chickweed populations that each homozygous for the specific target-site resistance-endowing mutations were characterized and the effect of these mutations on plant growth was assessed via relative growth rate (RGR) analysis. Plants homozygous for Pro197Ser and Pro197Leu exhibited higher extractable ALS activity than susceptible (S) plants, while all ALS mutations with no negative change in ALS kinetics. The Pro197Leu mutation increased ALS sensitivity to isoleucine and valine, and Pro197Glu mutation slightly increased ALS sensitivity to isoleucine. RGR results indicated that none of these ALS resistance mutations impose negative pleiotropic effects on relative growth rate. However, resistant (R) seeds had a lowed germination rate than S seeds. This study provides baseline information on ALS functionality and plant growth characteristics associated with ALS inhibitor resistance-endowing mutations in water chickweed. Copyright © 2017. Published by Elsevier Inc.

Linkage disequilibrium mapping of morphological, resistance, and other agronomically relevant traits in modern spring barley cultivars

NARCIS (Netherlands)

Kraakman, A.T.W.; Martinez, F.; Mussiraliev, B.; Eeuwijk, van F.A.; Niks, R.E.

2006-01-01

A set of 148 modern spring barley cultivars was explored for the extent of linkage disequilibrium (LD) between genes governing traits and nearby marker alleles. Associations of agronomically relevant traits (days to heading, plant height), resistance traits (leaf rust, barley yellow dwarf virus

RNAi technology extends its reach: Engineering plant resistance ...

African Journals Online (AJOL)

RNA interference (RNAi) is a homology-dependent gene silencing technology that is initiated by double stranded RNA (dsRNA). It has emerged as a genetic tool for engineering plants resistance against prokaryotic pathogens such as virus and bacteria. Recent studies broaden the role of RNAi, and many successful ...

Plant community resistance to invasion by Bromus species – the roles of community attributes, Bromus Interactions with plant communities, and Bromus traits

Science.gov (United States)

Chambers, Jeanne; Germino, Matthew; Belnap, Jayne; Brown, Cynthia; Schupp, Eugene W.; St. Clair, Samuel B

2016-01-01

The factors that determine plant community resistance to exotic annual Bromus species (Bromushereafter) are diverse and context specific. They are influenced by the environmental characteristics and attributes of the community, the traits of Bromus species, and the direct and indirect interactions of Bromus with the plant community. Environmental factors, in particular ambient and soil temperatures, have significant effects on the ability of Bromus to establish and spread. Seasonality of precipitation relative to temperature influences plant community resistance toBromus through effects on soil water storage, timing of water and nutrient availability, and dominant plant life forms. Differences among plant communities in how well soil resource use by the plant community matches resource supply rates can influence the magnitude of resource fluctuations due to either climate or disturbance and thus the opportunities for invasion. The spatial and temporal patterns of resource availability and acquisition of growth resources by Bromus versus native species strongly influence resistance to invasion. Traits of Bromus that confer a “priority advantage” for resource use in many communities include early-season germination and high growth and reproductive rates. Resistance to Bromus can be overwhelmed by high propagule supply, low innate seed dormancy, and large, if short-lived, seed banks. Biological crusts can inhibit germination and establishment of invasive annual plants, including several annual Bromus species, but are effective only in the absence of disturbance. Herbivores can have negative direct effects on Bromus, but positive indirect effects through decreases in competitors. Management strategies can be improved through increased understanding of community resistance to exotic annual Bromus species.

Modified cellulose synthase gene from 'Arabidopsis thaliana' confers herbicide resistance to plants

Energy Technology Data Exchange (ETDEWEB)

Somerville, Chris R.; Scieble, Wolf

2000-10-11

Cellulose synthase ('CS'), a key enzyme in the biosynthesis of cellulose in plants is inhibited by herbicides comprising thiazolidinones such as 5-tert-butyl-carbamoyloxy-3-(3-trifluromethyl) phenyl-4-thiazolidinone (TZ), isoxaben and 2,6-dichlorobenzonitrile (DCB). Two mutant genes encoding isoxaben and TZ-resistant cellulose synthase have been isolated from isoxaben and TZ-resistant Arabidopsis thaliana mutants. When compared with the gene coding for isoxaben or TZ-sensitive cellulose synthase, one of the resistant CS genes contains a point mutation, wherein glycine residue 998 is replaced by an aspartic acid. The other resistant mutation is due to a threonine to isoleucine change at amino acid residue 942. The mutant CS gene can be used to impart herbicide resistance to a plant; thereby permitting the utilization of the herbicide as a single application at a concentration which ensures the complete or substantially complete killing of weeds, while leaving the transgenic crop plant essentially undamaged.

[Effects and mechanisms of plant roots on slope reinforcement and soil erosion resistance: a research review].

Science.gov (United States)

Xiong, Yan-Mei; Xia, Han-Ping; Li, Zhi-An; Cai, Xi-An

2007-04-01

Plant roots play an important role in resisting the shallow landslip and topsoil erosion of slopes by raising soil shear strength. Among the models in interpreting the mechanisms of slope reinforcement by plant roots, Wu-Waldron model is a widely accepted one. In this model, the reinforced soil strength by plant roots is positively proportional to average root tensile strength and root area ratio, the two most important factors in evaluating slope reinforcement effect of plant roots. It was found that soil erosion resistance increased with the number of plant roots, though no consistent quantitative functional relationship was observed between them. The increase of soil erosion resistance by plant roots was mainly through the actions of fiber roots less than 1 mm in diameter, while fiber roots enhanced the soil stability to resist water dispersion via increasing the number and diameter of soil water-stable aggregates. Fine roots could also improve soil permeability effectively to decrease runoff and weaken soil erosion.

Effects of plant morphology on vegetation resistance, resilience and ...

African Journals Online (AJOL)

Effects of plant morphology on vegetation resistance, resilience and tolerance in. Mabira forest ... impacts of visitors activities of the camping sites and to understand the .... (Howard, 199 1 ): Milicia excels a, Cordia millenii, Irving/a gabonensis ...

within plant resistance to water flow in tomato and sweet melons

African Journals Online (AJOL)

Administrator

high pressure flow meter (HPFM) and evaporative flux (EF) methods. In the evaporative flux method, measure- ments of transpiration flux and leaf water potential were used to calculate the total resistance to water flow using. Ohm's law analogy. Measurements of tranpiration flux (Q) relationship, plant resistance calculated ...

Priming of plant resistance by natural compounds. Hexanoic acid as a model

Directory of Open Access Journals (Sweden)

Paz eAranega Bou

2014-10-01

Full Text Available Some alternative control strategies of currently emerging plant diseases are based on the use of resistance inducers. This review highlights the recent advances made in the characterization of natural compounds that induce resistance by a priming mechanism. These include vitamins, chitosans, oligogalacturonides, volatile organic compounds, azelaic and pipecolic acid, among others. Overall, other than providing novel disease control strategies that meet environmental regulations, natural priming agents are valuable tools to help unravel the complex mechanisms underlying the induced resistance phenomenon. The data presented in this review reflect the novel contributions made from studying these natural plant inducers, with special emphasis placed on hexanoic acid (Hx, proposed herein as a model tool for this research field. Hx is a potent natural priming agent of proven efficiency in a wide range of host plants and pathogens. It can early activate broad-spectrum defenses by inducing callose deposition and the SA and JA pathways. Later it can prime pathogen-specific responses according to the pathogen’s lifestyle. Interestingly, Hx primes redox-related genes to produce an anti-oxidant protective effect, which might be critical for limiting the infection of necrotrophs. Our Hx-induced resistance (Hx-IR findings also strongly suggest that it is an attractive tool for the molecular characterization of the plant alarmed state, with the added advantage of it being a natural compound.

Defoliation patterns in signal grass tillers with varying heights in the same pasture - doi: 10.4025/actascianimsci.v35i3.14376

Directory of Open Access Journals (Sweden)

Simone Pedro da Silva

2013-07-01

Full Text Available The experiment was carried out to evaluate the patterns of defoliation in plants of various heights in the same pasture of Brachiaria decumbens cv. Basilisk under continuous stocking with cattle. Four plant heights were evaluated (10, 20, 30 and 40 cm in the same managed sward, with mean height equal to 25 cm. A randomized blocks design was used, with two replications. Defoliation frequency increased linearly along with plant height in the same pasture. Defoliation intensity, number of defoliations in leaf blade and percentage of leaf blade grazed per tiller also increased linearly along with plant height. The defoliation interval decreased linearly according to plant height. The quadratic model was adequately fitted into grazing efficiency data, reaching the highest value (98% at the sward site with 35 cm plants. The percentage variation in signal grass height showed a negative linear response with initial plant height. The structure of the pasture, characterized by the diversity in plant heights, is simultaneously the cause and consequence of the variability in defoliation patterns in individual tillers, which occur on the horizontal plane of the pasture.  

Two distinct classes of QTL determine rust resistance in sorghum.

Science.gov (United States)

Wang, Xuemin; Mace, Emma; Hunt, Colleen; Cruickshank, Alan; Henzell, Robert; Parkes, Heidi; Jordan, David

2014-12-31

Agriculture is facing enormous challenges to feed a growing population in the face of rapidly evolving pests and pathogens. The rusts, in particular, are a major pathogen of cereal crops with the potential to cause large reductions in yield. Improving stable disease resistance is an on-going major and challenging focus for many plant breeding programs, due to the rapidly evolving nature of the pathogen. Sorghum is a major summer cereal crop that is also a host for a rust pathogen Puccinia purpurea, which occurs in almost all sorghum growing areas of the world, causing direct and indirect yield losses in sorghum worldwide, however knowledge about its genetic control is still limited. In order to further investigate this issue, QTL and association mapping methods were implemented to study rust resistance in three bi-parental populations and an association mapping set of elite breeding lines in different environments. In total, 64 significant or highly significant QTL and 21 suggestive rust resistance QTL were identified representing 55 unique genomic regions. Comparisons across populations within the current study and with rust QTL identified previously in both sorghum and maize revealed a high degree of correspondence in QTL location. Negative phenotypic correlations were observed between rust, maturity and height, indicating a trend for both early maturing and shorter genotypes to be more susceptible to rust. The significant amount of QTL co-location across traits, in addition to the consistency in the direction of QTL allele effects, has provided evidence to support pleiotropic QTL action across rust, height, maturity and stay-green, supporting the role of carbon stress in susceptibility to rust. Classical rust resistance QTL regions that did not co-locate with height, maturity or stay-green QTL were found to be significantly enriched for the defence-related NBS-encoding gene family, in contrast to the lack of defence-related gene enrichment in multi-trait effect

ANTIBACTERIAL ACTIVITY OF SOME WILD MEDICAL PLANTS EXTRACT TO ANTIBIOTIC RESISTANT ESCHERICHIA COLI

Directory of Open Access Journals (Sweden)

Lukáš Hleba

2013-02-01

Full Text Available Antibiotics are probably the most successful family of drugs so far developed for improving human health. Because of increasing resistance to antibiotics of many bacteria, plant extracts and plant compounds are of new interest as antiseptics and antimicrobial agents in medicine. In this study, we researched antimicrobial effects of extracts of some medical plants (Tussilagofarfara, Equisetum arvense, Sambucusnigra, Aesculushippocastanumand Taraxacumofficinale from Slovakia to antibiotic resistant and antibiotic sensitive bacteria isolated from milk of cows and mare, which were breeded in different conditions. Microorganisms which were used in this experiment we isolated from milk from conventional breeding of cows (tenE. coli strains and from ecological breeding of Lipicanmare (tenE. coli strains by sterile cotton swabs. For antibiotic susceptibility testing was used disc diffusion method according by EUCAST. After dried at room temperature we weighed 50 g of crushed medical plants (parts and it were to extract in 400 ml methanol for two weeks at room temperature. For antimicrobial susceptibility testing of medical plants extract blank discs with 6 mm diameter disc diffusion method was used. We determined that all Escherichia coli strains isolated from milk of conventional breeding of cows were resistant to ampicillin and chloramphenicol. We determined that all tested ampicillin and chloramphenicol resistant E. coli strains isolated from conventional breeding of cow showed susceptibility to all used medical plants extracts. In difference, we determined that antibiotic susceptible E. coli strains isolated from ecological breeding of Lipicanmare were susceptible to Tussilagofarfara extract only. From these results we could be conclude some observations, which could be important step in treatment of bacterial infections caused by antibiotic resistant bacteria and it could be important knowledge for treatment of livestock in conventional breeding

Bacterial Gibberellins Induce Systemic Resistance of Plants

Directory of Open Access Journals (Sweden)

I. N. FEKLISTOVA

2014-06-01

Full Text Available It is generally agreed today that some rhizosphere bacteria can ensure induced systemic resistance to pathogens. In this paper we tested the ability of gibberellins produced by rhizosphere non-pathogenic bacteria Pseudomonas aurantiaca to induce systemic resistance to alternariosis agent – Alternaria brassicicola – in oilseed rape plants.Oilseed rape (Brássica nápus is one of the most promising oil-bearing croppers. It allows improving the supply of population with vegetable oil, animal and poultry industries with high quality vegetable protein. It is used for biofuel production as well.Gibberellin preparation was isolated from liquid culture of strain Pseudomonas aurantiaca grown in 250 mL of M9 medium (48 h, 28 °C under darkroom conditions. Gibberellins were extracted according procedure described by Tien et al. (1979. Gibberellins concentration in the medium was determined by fluorometric method.Elicitor activity of bacterial metabolites – gibberellins – was analyzed in model system of artificial inoculation of oilseed rape germs with phytopathogenic fungi Alternaria brassicicola. The elicitor action efficiency was evaluated on the 15th day of oilseed rape cultivation based on the percentage of leaf surface covered by necrotic lesions.Gibberellins were shown to induce systemic resistance resulted in decreasing of oil seed plants   vulnerability by 52.7%.It is known that under the unfavorable conditions plants synthesis the reactive oxygen intermediates   which activate destructive processes. One of the first organism reactions to stress action is the change of the lipid peroxidation level. It was shown that treatment of the soil with gibberellins resulted in decreasing of the lipid peroxidation level twofold.Gibberellins were shown to have a similar effect on permeability of cell membranes for free nucleotides. The permeability of cell membranes in leaves decreased 2.8-fold at room temperature. We suggest that gibberellins

Parasitic plants of the genus Cuscuta and their interaction with susceptible and resistant host plants

Directory of Open Access Journals (Sweden)

Bettina eKaiser

2015-02-01

Full Text Available By comparison with plant-microbe interaction, little is known about the interaction of parasitic plants with their hosts. Plants of the genus Cuscuta belong to the family of Cuscutaceae and comprise about 200 species, all of which live as stem holoparasites on other plants. Cuscuta spp. possess no roots nor fully expanded leaves and the vegetative portion appears to be a stem only. The parasite winds around plants and penetrates the host stems via haustoria, forming direct connections to the vascular bundles of their hosts to withdraw water, carbohydrates and other solutes. Besides susceptible hosts, a few plants exist that exhibit an active resistance against infestation by Cuscuta spp. For example, cultivated tomato (Solanum lycopersicum fends off Cuscuta reflexa by means of a hypersensitive-type response occurring in the early penetration phase. This report on the plant-plant dialogue between Cuscuta spp. and its host plants focuses on the incompatible interaction of Cuscuta reflexa with tomato.

Parasitic plants of the genus Cuscuta and their interaction with susceptible and resistant host plants.

Science.gov (United States)

Kaiser, Bettina; Vogg, Gerd; Fürst, Ursula B; Albert, Markus

2015-01-01

By comparison with plant-microbe interaction, little is known about the interaction of parasitic plants with their hosts. Plants of the genus Cuscuta belong to the family of Cuscutaceae and comprise about 200 species, all of which live as stem holoparasites on other plants. Cuscuta spp. possess no roots nor fully expanded leaves and the vegetative portion appears to be a stem only. The parasite winds around plants and penetrates the host stems via haustoria, forming direct connections to the vascular bundles of their hosts to withdraw water, carbohydrates, and other solutes. Besides susceptible hosts, a few plants exist that exhibit an active resistance against infestation by Cuscuta spp. For example, cultivated tomato (Solanum lycopersicum) fends off Cuscuta reflexa by means of a hypersensitive-type response occurring in the early penetration phase. This report on the plant-plant dialog between Cuscuta spp. and its host plants focuses on the incompatible interaction of C. reflexa with tomato.

Within plant resistance to water flow in tomato and sweet melons ...

African Journals Online (AJOL)

In the evaporative flux method, measurements of transpiration flux and leaf water potential were used to calculate the total resistance to water flow using Ohm's law analogy. Measurements of tranpiration flux (Q) relationship, plant resistance calculated from the slope of their relationship, ranged from 6.57x10-01 to ...

Plant-to-plant communication triggered by systemin primes anti-herbivore resistance in tomato.

Science.gov (United States)

Coppola, Mariangela; Cascone, Pasquale; Madonna, Valentina; Di Lelio, Ilaria; Esposito, Francesco; Avitabile, Concetta; Romanelli, Alessandra; Guerrieri, Emilio; Vitiello, Alessia; Pennacchio, Francesco; Rao, Rosa; Corrado, Giandomenico

2017-11-14

Plants actively respond to herbivory by inducing various defense mechanisms in both damaged (locally) and non-damaged tissues (systemically). In addition, it is currently widely accepted that plant-to-plant communication allows specific neighbors to be warned of likely incoming stress (defense priming). Systemin is a plant peptide hormone promoting the systemic response to herbivory in tomato. This 18-aa peptide is also able to induce the release of bioactive Volatile Organic Compounds, thus also promoting the interaction between the tomato and the third trophic level (e.g. predators and parasitoids of insect pests). In this work, using a combination of gene expression (RNA-Seq and qRT-PCR), behavioral and chemical approaches, we demonstrate that systemin triggers metabolic changes of the plant that are capable of inducing a primed state in neighboring unchallenged plants. At the molecular level, the primed state is mainly associated with an elevated transcription of pattern -recognition receptors, signaling enzymes and transcription factors. Compared to naïve plants, systemin-primed plants were significantly more resistant to herbivorous pests, more attractive to parasitoids and showed an increased response to wounding. Small peptides are nowadays considered fundamental signaling molecules in many plant processes and this work extends the range of downstream effects of this class of molecules to intraspecific plant-to-plant communication.

RNA Interference: A Novel Source of Resistance to Combat Plant Parasitic Nematodes

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Sagar Banerjee

2017-05-01

Full Text Available Plant parasitic nematodes cause severe damage and yield loss in major crops all over the world. Available control strategies include use of insecticides/nematicides but these have proved detrimental to the environment, while other strategies like crop rotation and resistant cultivars have serious limitations. This scenario provides an opportunity for the utilization of technological advances like RNA interference (RNAi to engineer resistance against these devastating parasites. First demonstrated in the model free living nematode, Caenorhabtidis elegans; the phenomenon of RNAi has been successfully used to suppress essential genes of plant parasitic nematodes involved in parasitism, nematode development and mRNA metabolism. Synthetic neurotransmitants mixed with dsRNA solutions are used for in vitro RNAi in plant parasitic nematodes with significant success. However, host delivered in planta RNAi has proved to be a pioneering phenomenon to deliver dsRNAs to feeding nematodes and silence the target genes to achieve resistance. Highly enriched genomic databases are exploited to limit off target effects and ensure sequence specific silencing. Technological advances like gene stacking and use of nematode inducible and tissue specific promoters can further enhance the utility of RNAi based transgenics against plant parasitic nematodes.

Development of Efficient Screening Methods for Resistant Cucumber Plants to Meloidogyne incognita

Directory of Open Access Journals (Sweden)

Sung Min Hwang

2014-06-01

Full Text Available Root-knot nematodes represent a significant problem in cucumber, causing reduction in yield and quality. To develop screening methods for resistance of cucumber to root-knot nematode Meloidogyne incognita, development of root-knot nematode of four cucumber cultivars (‘Dragonsamchuk’, ‘Asiastrike’, ‘Nebakja’ and ‘Hanelbakdadaki’ according to several conditions such as inoculum concentration, plant growth stage and transplanting period was investigated by the number of galls and egg masses produced in each seedling 45 days after inoculation. There was no difference in galls and egg masses according to the tested condition except for inoculum concentration. Reproduction of the nematode on all the tested cultivars according to inoculum concentration increased in a dose-dependent manner. On the basis of the result, the optimum conditions for root-knot development on the cultivars is to transplant period of 1 week, inoculum concentration of 5,000 eggs/plant and plant growth stage of 3-week-old in a greenhouse (25 ± 5°C. In addition, under optimum conditions, resistance of 45 commercial cucumber cultivars was evaluated. One rootstock cultivar, Union was moderately resistant to the root-knot nematode. However, no significant difference was in the resistance of the others cultivar. According to the result, we suggest an efficient screening method for new resistant cucumber to the root-knot nematode, M. incognita.

Improvement of resistance to rust through recurrent selection in pearl millet

Energy Technology Data Exchange (ETDEWEB)

Tapsoba, H. [Univ. of Georgia, Athens, GA (United States); Wilson, J.P.; Hanna, W.W. [Univ. of Georgia Coastal Plain Experimental Station, Tifton, GA (United States)

1997-04-01

Two pearl millet [Pennisetum glaucum (L.) R.Br. = P. typhoides (Burm.) Staff & Hubb., P. americanum (L.) K. Schum.] bulk populations, Tift No. 2 and Tift No. 5, served as base populations for four cycles of recurrent selection against susceptibility to Puccinia substriata Ell. & Barth, var. indica Ramachar & Cumm. A bulk inoculum of the pathogen was used. The objectives were to evaluate the progress achieved regarding overall resistance to the pathogen in the field and resistance to different races of the pathogen, and also to evaluate changes in unselected traits. During selection, the frequency of rust resistant plants continuously increased from about 30% in each base population to more than 85% by the third cycle of selection in both populations. An average increase of about 21 and 18% per cycle was obtained in Tift No. 2 and Tift No. 5, respectively. A continuous increase of the frequency of plants resistant to some races of the pathogen was also obtained. In Tift No. 5, 80% of the plants were resistant to eight races by the third cycle of selection. The accumulation of resistance observed in the seedlings was manifested in the field, both in 1993 and 1994, by a reduction of the final rust severity from the base population to the fourth selection cycle of both populations. This improvement in resistance to the rust pathogen was accompanied by an increase in the frequency of plants resistant to Pyricularia grisea (Cooke) Sacc. only in Tift No. 2. Despite the improvement in the selected character, genetic variability for agronomic traits such as plant height, number of culms/plant, flowering date, and panicle length was successfully maintained within each population. 20 refs., 1 fig., 7 tabs.

High-throughput phenotyping of plant resistance to aphids by automated video tracking

NARCIS (Netherlands)

Kloth, K.J.; Broeke, ten C.J.M.; Thoen, H.P.M.; Hanhart-van den Brink, M.; Wiegers, G.L.; Krips, O.E.; Noldus, L.P.J.J.; Dicke, M.; Jongsma, M.A.

2015-01-01

Background: Piercing-sucking insects are major vectors of plant viruses causing significant yield losses in crops.Functional genomics of plant resistance to these insects would greatly benefit from the availability of highthroughput, quantitative phenotyping methods. Results: We have developed an

Effect of pruning height on the architecture of plants of camu camu (Myrciaria dubia HBK Mc Vaugh in the experimental station of IIAP, Ucayali, Peru.

Directory of Open Access Journals (Sweden)

Carlos Abanto

2011-06-01

Full Text Available In order to evaluate the response camu camu’s plants in plantations initial undergoing training pruning, an experiment was installed in EE - IIAP-Ucayali, under a design randomized complete block, with 3 replications, making use of 20 plants per experimental unit. The pruning treatments were performing at different heights from the base of the stem, it was considered T0 [witness without pruning], T1 [pruning to 10 cm from the base], T2 [pruning to 20 cm from the base] and T3 [pruning to 40 cm from the base] in plants of known provenance. The investigation was directed to evaluate the number of shoots, shoot growth, plant height, basal diameter, crown diameter and number of branches. After of 9 months of evaluation was found significant differences between the variables except in top diameter. In the variable Height, treatment T0 [witness without pruning] outstanding because they were not pruned, among the remaining treatments has similarly behaved, surpassing the control treatment by 267 %. In addition to this, the basal diameter was found that T1 [pruning to 10 cm from the base] has a better performed with an average value of 1.96 cm compared with the control (1.7cm. The pruning had a positive influence in the number of branches, with an average of 13.4 branches compared with T0 that get 3.1 branches on average, its shows that the pruning can increased up the production of branches to 432.3%.

Pyramiding, alternating or mixing: comparative performances of deployment strategies of nematode resistance genes to promote plant resistance efficiency and durability.

Science.gov (United States)

Djian-Caporalino, Caroline; Palloix, Alain; Fazari, Ariane; Marteu, Nathalie; Barbary, Arnaud; Abad, Pierre; Sage-Palloix, Anne-Marie; Mateille, Thierry; Risso, Sabine; Lanza, Roger; Taussig, Catherine; Castagnone-Sereno, Philippe

2014-02-22

Resistant cultivars are key elements for pathogen control and pesticide reduction, but their repeated use may lead to the emergence of virulent pathogen populations, able to overcome the resistance. Increased research efforts, mainly based on theoretical studies, explore spatio-temporal deployment strategies of resistance genes in order to maximize their durability. We evaluated experimentally three of these strategies to control root-knot nematodes: cultivar mixtures, alternating and pyramiding resistance genes, under controlled and field conditions over a 3-years period, assessing the efficiency and the durability of resistance in a protected crop rotation system with pepper as summer crop and lettuce as winter crop. The choice of the resistance gene and the genetic background in which it is introgressed, affected the frequency of resistance breakdown. The pyramiding of two different resistance genes in one genotype suppressed the emergence of virulent isolates. Alternating different resistance genes in rotation was also efficient to decrease virulent populations in fields due to the specificity of the virulence and the trapping effect of resistant plants. Mixing resistant cultivars together appeared as a less efficient strategy to control nematodes. This work provides experimental evidence that, in a cropping system with seasonal sequences of vegetable species, pyramiding or alternating resistance genes benefit yields in the long-term by increasing the durability of resistant cultivars and improving the long-term control of a soil-borne pest. To our knowledge, this result is the first one obtained for a plant-nematode interaction, which helps demonstrate the general applicability of such strategies for breeding and sustainable management of resistant cultivars against pathogens.

The height of watermelons with wall

International Nuclear Information System (INIS)

Feierl, Thomas

2012-01-01

We derive asymptotics for the moments as well as the weak limit of the height distribution of watermelons with p branches with wall. This generalizes a famous result of de Bruijn et al (1972 Graph Theory and Computing (New York: Academic) pp 15–22) on the average height of planted plane trees, and results by Fulmek (2007 Electron. J. Combin. 14 R64) and Katori et al (2008 J. Stat. Phys. 131 1067–83) on the expected value and higher moments, respectively, of the height distribution of watermelons with two branches. The asymptotics for the moments depend on the analytic behaviour of certain multidimensional Dirichlet series. In order to obtain this information, we prove a reciprocity relation satisfied by the derivatives of one of Jacobi’s theta functions, which generalizes the well-known reciprocity law for Jacobi’s theta functions. (paper)

Towards allele mining of bacterial wilt disease resistance gene in tomato

International Nuclear Information System (INIS)

Galvez, H.F.; Narciso, J.O.; Opina, N.L.; Canama, A.O.; Colle, M.G.; Latiza, M.A.; Caspillo, C.L.; Bituin, J.L.; Frankie, R.B.; Hautea, D.M.

2005-01-01

Tomato (Lycopersicon esculentum Mill.) is the most important vegetable commodity of the Philippines. Bacterial wilt caused by Ralstonia solanacearum is one serious constraint in tomato production particularly during off-season planting. A major locus derived from H7996 that confers resistance to bacterial wilt has been mapped in the tomato genome. To validate the biological function of the resistance locus and generate multiple allele -mimics-, targeted mutation was induced in tomato using gamma ray and ethyl methane sulfonate (EMS) mutagens. Suitable mutagen treatment was established by evaluating a wide range of mutagen doses/concentrations for a) percent seed germination, b) reduction in plant height, and c) loss of resistance. Six hundred Gy and 1.0% EMS were identified to generate large M1 families of H7996. From 10,000 initial seeds treated with either gamma ray or EMS, a total of 3,663 M1 plants were generated. M2 seeds were harvested from all surviving M1 plants. Several DNA markers have been resourced and are being developed specific to the bacterial wilt resistant gene. In the large M2 population, of H7996, both the phenotypic manifestation of bacterial wilt susceptibility and nucleotide changes in the resistance locus will be evaluated. Large M3 families for the different allele series of the bacterial wilt resistance gene will be established for future high throughput TILLING (Targeting Induced Local Lesions in Genomes) analysis in the gene region

The Effect of Temperature and Host Plant Resistance on Population Growth of the Soybean Aphid Biotype 1 (Hemiptera: Aphididae).

Science.gov (United States)

Hough, Ashley R; Nechols, James R; McCornack, Brian P; Margolies, David C; Sandercock, Brett K; Yan, Donglin; Murray, Leigh

2017-02-01

A laboratory experiment was conducted to evaluate direct and indirect effects of temperature on demographic traits and population growth of biotype 1 of the soybean aphid, Aphis glycines Matsumura. Our objectives were to better understand how temperature influences the expression of host plant resistance, quantify the individual and interactive effects of plant resistance and temperature on soybean aphid population growth, and generate thermal constants for predicting temperature-dependent development on both susceptible and resistant soybeans. To assess indirect (plant-mediated) effects, soybean aphids were reared under a range of temperatures (15-30 °C) on soybean seedlings from a line expressing a Rag1 gene for resistance, and life history traits were quantified and compared to those obtained for soybean aphids on a susceptible soybean line. Direct effects of temperature were obtained by comparing relative differences in the magnitude of life-history traits among temperatures on susceptible soybeans. We predicted that temperature and host plant resistance would have a combined, but asymmetrical, effect on soybean aphid fitness and population growth. Results showed that temperature and plant resistance influenced preimaginal development and survival, progeny produced, and adult longevity. There also appeared to be a complex interaction between temperature and plant resistance for survival and developmental rate. Evidence suggested that the level of plant resistance increased at higher, but not lower, temperature. Soybean aphids required about the same number of degree-days to develop on resistant and susceptible plants. Our results will be useful for making predictions of soybean aphid population growth on resistant plants under different seasonal temperatures. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Testing Transgenic Aspen Plants with bar Gene for Herbicide Resistance under Semi-natural Conditions.

Science.gov (United States)

Lebedev, V G; Faskhiev, V N; Kovalenko, N P; Shestibratov, K A; Miroshnikov, A I

2016-01-01

Obtaining herbicide resistant plants is an important task in the genetic engineering of forest trees. Transgenic European aspen plants (Populus tremula L.) expressing the bar gene for phosphinothricin resistance have been produced using Agrobacterium tumefaciens-mediated transformation. Successful genetic transformation was confirmed by PCR analysis for thirteen lines derived from two elite genotypes. In 2014-2015, six lines were evaluated for resistance to herbicide treatment under semi-natural conditions. All selected transgenic lines were resistant to the herbicide Basta at doses equivalent to 10 l/ha (twofold normal field dosage) whereas the control plants died at 2.5 l/ha. Foliar NH4-N concentrations in transgenic plants did not change after treatment. Extremely low temperatures in the third ten-day period of October 2014 revealed differences in freeze tolerance between the lines obtained from Pt of f2 aspen genotypes. Stable expression of the bar gene after overwintering outdoors was confirmed by RT-PCR. On the basis of the tests, four transgenic aspen lines were selected. The bar gene could be used for retransformation of transgenic forest trees expressing valuable traits, such as increased productivity.

Antimicrobial Resistance and the Alternative Resources with Special Emphasis on Plant-Based Antimicrobials—A Review

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Harish Chandra

2017-04-01

Full Text Available Indiscriminate and irrational use of antibiotics has created an unprecedented challenge for human civilization due to microbe’s development of antimicrobial resistance. It is difficult to treat bacterial infection due to bacteria’s ability to develop resistance against antimicrobial agents. Antimicrobial agents are categorized according to their mechanism of action, i.e., interference with cell wall synthesis, DNA and RNA synthesis, lysis of the bacterial membrane, inhibition of protein synthesis, inhibition of metabolic pathways, etc. Bacteria may become resistant by antibiotic inactivation, target modification, efflux pump and plasmidic efflux. Currently, the clinically available treatment is not effective against the antibiotic resistance developed by some bacterial species. However, plant-based antimicrobials have immense potential to combat bacterial, fungal, protozoal and viral diseases without any known side effects. Such plant metabolites include quinines, alkaloids, lectins, polypeptides, flavones, flavonoids, flavonols, coumarin, terpenoids, essential oils and tannins. The present review focuses on antibiotic resistance, the resistance mechanism in bacteria against antibiotics and the role of plant-active secondary metabolites against microorganisms, which might be useful as an alternative and effective strategy to break the resistance among microbes.

PRGdb 3.0: a comprehensive platform for prediction and analysis of plant disease resistance genes.

Science.gov (United States)

Osuna-Cruz, Cristina M; Paytuvi-Gallart, Andreu; Di Donato, Antimo; Sundesha, Vicky; Andolfo, Giuseppe; Aiese Cigliano, Riccardo; Sanseverino, Walter; Ercolano, Maria R

2018-01-04

The Plant Resistance Genes database (PRGdb; http://prgdb.org) has been redesigned with a new user interface, new sections, new tools and new data for genetic improvement, allowing easy access not only to the plant science research community but also to breeders who want to improve plant disease resistance. The home page offers an overview of easy-to-read search boxes that streamline data queries and directly show plant species for which data from candidate or cloned genes have been collected. Bulk data files and curated resistance gene annotations are made available for each plant species hosted. The new Gene Model view offers detailed information on each cloned resistance gene structure to highlight shared attributes with other genes. PRGdb 3.0 offers 153 reference resistance genes and 177 072 annotated candidate Pathogen Receptor Genes (PRGs). Compared to the previous release, the number of putative genes has been increased from 106 to 177 K from 76 sequenced Viridiplantae and algae genomes. The DRAGO 2 tool, which automatically annotates and predicts (PRGs) from DNA and amino acid with high accuracy and sensitivity, has been added. BLAST search has been implemented to offer users the opportunity to annotate and compare their own sequences. The improved section on plant diseases displays useful information linked to genes and genomes to connect complementary data and better address specific needs. Through, a revised and enlarged collection of data, the development of new tools and a renewed portal, PRGdb 3.0 engages the plant science community in developing a consensus plan to improve knowledge and strategies to fight diseases that afflict main crops and other plants. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Analysis of the genetic basis of plant height-related traits in response to ethylene by QTL mapping in maize (Zea mays L.).

Science.gov (United States)

Zhang, Weiqiang; Li, Zhi; Fang, Hui; Zhang, Mingcai; Duan, Liusheng

2018-01-01

Ethylene (ET) is critical importance in the growth, development, and stress responses of plants. Plant hormonal stress responses have been extensively studied, however, the role of ET in plant growth, especially plant height (PH) remains unclear. Understanding the genetic control for PH in response to ET will provide insights into the regulation of maize development. To clarify the genetic basis of PH-related traits of maize in response to ET, we mapped QTLs for PH, ear height (EH), and internode length above the uppermost ear (ILAU) in two recombinant inbred line (RIL) populations of Zea mays after ET treatment and in an untreated control (CK) group. Sixty QTLs for the three traits were identified. Twenty-two QTLs were simultaneously detected under both ET treatment and untreated control, and five QTLs were detected at two geographic locations under ET treatment only. Individual QTL can be explained 3.87-17.71% of the phenotypic variance. One QTL (q2PH9-1, q1PH9, q1EH9/q1ILAU9-1, q2ILAU9, and q2EH9) for the measured traits (PH, EH, ILAU) was consistent across both populations. Two QTLs (q2PH2-5, q2ILAU2-2, q1PH2-2, and q1ILAU2-2; q1PH8-1, q1EH8-1, q2PH8-1) were identified for up to two traits in both locations and populations under both ET treatment and untreated control. These consistent and stable regions are important QTLs of potential hot spots for PH, ear height (EH), and internode length above the uppermost ear (ILAU) response to ET in maize; therefore, QTL fine-mapping and putative candidate genes validation should enable the cloning of PH, EH, and ILAU related genes to ET response. These results will be valuable for further fine-mapping and quantitative trait nucleotides (QTNs) determination, and elucidate the underlying molecular mechanisms of ET responses in maize.

Analysis of the genetic basis of plant height-related traits in response to ethylene by QTL mapping in maize (Zea mays L..

Directory of Open Access Journals (Sweden)

Weiqiang Zhang

Full Text Available Ethylene (ET is critical importance in the growth, development, and stress responses of plants. Plant hormonal stress responses have been extensively studied, however, the role of ET in plant growth, especially plant height (PH remains unclear. Understanding the genetic control for PH in response to ET will provide insights into the regulation of maize development. To clarify the genetic basis of PH-related traits of maize in response to ET, we mapped QTLs for PH, ear height (EH, and internode length above the uppermost ear (ILAU in two recombinant inbred line (RIL populations of Zea mays after ET treatment and in an untreated control (CK group. Sixty QTLs for the three traits were identified. Twenty-two QTLs were simultaneously detected under both ET treatment and untreated control, and five QTLs were detected at two geographic locations under ET treatment only. Individual QTL can be explained 3.87-17.71% of the phenotypic variance. One QTL (q2PH9-1, q1PH9, q1EH9/q1ILAU9-1, q2ILAU9, and q2EH9 for the measured traits (PH, EH, ILAU was consistent across both populations. Two QTLs (q2PH2-5, q2ILAU2-2, q1PH2-2, and q1ILAU2-2; q1PH8-1, q1EH8-1, q2PH8-1 were identified for up to two traits in both locations and populations under both ET treatment and untreated control. These consistent and stable regions are important QTLs of potential hot spots for PH, ear height (EH, and internode length above the uppermost ear (ILAU response to ET in maize; therefore, QTL fine-mapping and putative candidate genes validation should enable the cloning of PH, EH, and ILAU related genes to ET response. These results will be valuable for further fine-mapping and quantitative trait nucleotides (QTNs determination, and elucidate the underlying molecular mechanisms of ET responses in maize.

Analysis of the genetic basis of plant height-related traits in response to ethylene by QTL mapping in maize (Zea mays L.)

Science.gov (United States)

Li, Zhi; Fang, Hui; Zhang, Mingcai; Duan, Liusheng

2018-01-01

Ethylene (ET) is critical importance in the growth, development, and stress responses of plants. Plant hormonal stress responses have been extensively studied, however, the role of ET in plant growth, especially plant height (PH) remains unclear. Understanding the genetic control for PH in response to ET will provide insights into the regulation of maize development. To clarify the genetic basis of PH-related traits of maize in response to ET, we mapped QTLs for PH, ear height (EH), and internode length above the uppermost ear (ILAU) in two recombinant inbred line (RIL) populations of Zea mays after ET treatment and in an untreated control (CK) group. Sixty QTLs for the three traits were identified. Twenty-two QTLs were simultaneously detected under both ET treatment and untreated control, and five QTLs were detected at two geographic locations under ET treatment only. Individual QTL can be explained 3.87–17.71% of the phenotypic variance. One QTL (q2PH9-1, q1PH9, q1EH9/q1ILAU9-1, q2ILAU9, and q2EH9) for the measured traits (PH, EH, ILAU) was consistent across both populations. Two QTLs (q2PH2-5, q2ILAU2-2, q1PH2-2, and q1ILAU2-2; q1PH8-1, q1EH8-1, q2PH8-1) were identified for up to two traits in both locations and populations under both ET treatment and untreated control. These consistent and stable regions are important QTLs of potential hot spots for PH, ear height (EH), and internode length above the uppermost ear (ILAU) response to ET in maize; therefore, QTL fine-mapping and putative candidate genes validation should enable the cloning of PH, EH, and ILAU related genes to ET response. These results will be valuable for further fine-mapping and quantitative trait nucleotides (QTNs) determination, and elucidate the underlying molecular mechanisms of ET responses in maize. PMID:29466465

Early warning of cotton bollworm resistance associated with intensive planting of Bt cotton in China.

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Haonan Zhang

Full Text Available Transgenic crops producing Bacillus thuringiensis (Bt toxins kill some key insect pests, but evolution of resistance by pests can reduce their efficacy. The predominant strategy for delaying pest resistance to Bt crops requires refuges of non-Bt host plants to promote survival of susceptible pests. To delay pest resistance to transgenic cotton producing Bt toxin Cry1Ac, farmers in the United States and Australia planted refuges of non-Bt cotton, while farmers in China have relied on "natural" refuges of non-Bt host plants other than cotton. Here we report data from a 2010 survey showing field-evolved resistance to Cry1Ac of the major target pest, cotton bollworm (Helicoverpa armigera, in northern China. Laboratory bioassay results show that susceptibility to Cry1Ac was significantly lower in 13 field populations from northern China, where Bt cotton has been planted intensively, than in two populations from sites in northwestern China where exposure to Bt cotton has been limited. Susceptibility to Bt toxin Cry2Ab did not differ between northern and northwestern China, demonstrating that resistance to Cry1Ac did not cause cross-resistance to Cry2Ab, and implying that resistance to Cry1Ac in northern China is a specific adaptation caused by exposure to this toxin in Bt cotton. Despite the resistance detected in laboratory bioassays, control failures of Bt cotton have not been reported in China. This early warning may spur proactive countermeasures, including a switch to transgenic cotton producing two or more toxins distinct from Cry1A toxins.

A modern Green Revolution gene for reduced height in wheat.

Science.gov (United States)

Würschum, Tobias; Langer, Simon M; Longin, C Friedrich H; Tucker, Matthew R; Leiser, Willmar L

2017-12-01

Increases in the yield of wheat during the Green Revolution of the late 20 th century were achieved through the introduction of Reduced height (Rht) dwarfing genes. The Rht-B1 and Rht-D1 loci ensured short stature by limiting the response to the growth-promoting hormone gibberellin, and are now widespread through international breeding programs. Despite this advantage, interference with the plant's response to gibberellin also triggers adverse effects for a range of important agronomic traits, and consequently modern Green Revolution genes are urgently required. In this study, we revisited the genetic control of wheat height using an association mapping approach and a large panel of 1110 worldwide winter wheat cultivars. This led to the identification of a major Rht locus on chromosome 6A, Rht24, which substantially reduces plant height alone as well as in combination with Rht-1b alleles. Remarkably, behind Rht-D1, Rht24 was the second most important locus for reduced height, explaining 15.0% of the genotypic variance and exerting an allele substitution effect of -8.8 cm. Unlike the two Rht-1b alleles, plants carrying Rht24 remain sensitive to gibberellic acid treatment. Rht24 appears in breeding programs from all countries of origin investigated, with increased frequency over the last decades, indicating that wheat breeders have actively selected for this locus. Taken together, this study reveals Rht24 as an important Rht gene of commercial relevance in worldwide wheat breeding. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

Kanamycin resistance during in vitro development of pollen from transgenic tomato plants

NARCIS (Netherlands)

Bino, R.J.; Hille, J.; Franken, J.

1987-01-01

Effects of kanamycin on pollen germination and tube growth of pollen from non-transformed plants and from transgenic tomato plants containing a chimaeric kanamycin resistance gene were determined. Germination of pollen was not affected by the addition of kanamycin to the medium in both genotypes.

Diversity and antibiotic resistance of Aeromonas spp. in drinking and waste water treatment plants.

Science.gov (United States)

Figueira, Vânia; Vaz-Moreira, Ivone; Silva, Márcia; Manaia, Célia M

2011-11-01

The taxonomic diversity and antibiotic resistance phenotypes of aeromonads were examined in samples from drinking and waste water treatment plants (surface, ground and disinfected water in a drinking water treatment plant, and raw and treated waste water) and tap water. Bacteria identification and intra-species variation were determined based on the analysis of the 16S rRNA, gyrB and cpn60 gene sequences. Resistance phenotypes were determined using the disc diffusion method. Aeromonas veronii prevailed in raw surface water, Aeromonas hydrophyla in ozonated water, and Aeromonas media and Aeromonas puntacta in waste water. No aeromonads were detected in ground water, after the chlorination tank or in tap water. Resistance to ceftazidime or meropenem was detected in isolates from the drinking water treatment plant and waste water isolates were intrinsically resistant to nalidixic acid. Most of the times, quinolone resistance was associated with the gyrA mutation in serine 83. The gene qnrS, but not the genes qnrA, B, C, D or qepA, was detected in both surface and waste water isolates. The gene aac(6')-ib-cr was detected in different waste water strains isolated in the presence of ciprofloxacin. Both quinolone resistance genes were detected only in the species A. media. This is the first study tracking antimicrobial resistance in aeromonads in drinking, tap and waste water and the importance of these bacteria as vectors of resistance in aquatic environments is discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Sexual Orientation, Objective Height, and Self-Reported Height.

Science.gov (United States)

Skorska, Malvina N; Bogaert, Anthony F

2017-01-01

Studies that have used mostly self-reported height have found that androphilic men and women are shorter than gynephilic men and women, respectively. This study examined whether an objective height difference exists or whether a psychosocial account (e.g., distortion of self-reports) may explain these putative height differences. A total of 863 participants, recruited at a Canadian university, the surrounding region, and through lesbian, gay, bisexual, and transgender (LGBT) events across Canada, self-reported their height and had their height measured. Androphilic men were shorter, on average, than gynephilic men. There was no objective height difference between gynephilic, ambiphilic, and androphilic women. Self-reported height, statistically controlling for objective height, was not related to sexual orientation. These findings are the first to show an objective height difference between androphilic and gynephilic men. Also, the findings suggest that previous studies using self-reported height found part of a true objective height difference between androphilic and gynephilic men. These findings have implications for existing biological theories of men's sexual orientation development.

Inheritance and heritability of resistance to citrus leprosis.

Science.gov (United States)

Bastianel, Marinês; de Oliveira, Antonio Carlos; Cristofani, Mariângela; Filho, Oliveiro Guerreiro; Freitas-Astúa, Juliana; Rodrigues, Vandeclei; Astúa-Monge, Gustavo; Machado, Marcos Antônio

2006-10-01

ABSTRACT The genetic inheritance of resistance to leprosis, the most important viral disease of citrus in Brazil, was characterized through the phenotypic assessment of 143 hybrids resulting from crosses between tangor 'Murcott' (Citrus sinensis x C. reticulata) and sweet orange 'Pêra' (C. sinensis), considered to be resistant and susceptible to the disease, respectively. All plants were grafted onto Rangpur lime (C. limonia) and inoculated with Citrus leprosis virus, cytoplasmic type through the infestation with viruliferous mites, Brevipalpus phoenicis. The experiments were arranged in a completely randomized block design with 10 replicates. Incidence and severity of the disease in leaves and stems as well as plant growth parameters (plant height and stem diameter) were recorded for 3 years after the infestation with the viruliferous mites. The average values of all variables were analyzed using principal component analysis, discriminant factorial analysis, estimation of the clonal repeatability coefficients, and frequency of the distributions of the average values for each measured variable. The principal component analysis resulted in the identification of at least two groups with resistance and susceptibility to leprosis, respectively. About 99% of all hybrids were correctly classified according to the discriminant factorial analysis. The broad-sense heritability coefficients for characteristics associated with incidence and severity of leprosis ranged from 0.88 to 0.96. The data suggest that the inheritance of resistance to leprosis may be controlled by only a few genes.

CHEMICAL COMPOSITION AND NUTRITIVE VALUE OF MAIZE STEMS DEPENDING ON THE CUTTING HEIGHT OF PLANTS AT HARVEST

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Ireneus KOWALIK

2013-12-01

Full Text Available Studies were carried out in the two years in Trzcianka near Nowy Tomyśl, on brown soil, IIIa – IVa with pH 7.1 – 7.2. Plants of five maize cultivars were cut at the height of 15 cm and 55 cm. The lower parts of stems with leaves which remain on the field in case of high cutting, were characterized by a smaller content of protein and by a greater content of fibre, in comparison with the higher parts of plants. The energetic value of 1 kg of dry matter of the lower 40 cm part with leaves expressed in MJ NEL, in spite of significant differences in the chemical composition, was only insignificantly lower than the upper part. The content of dry matter, the chemical composition and the energetic value of both parts differed, depending on the cultivar.

Evolution of resistance to a multiple-herbivore community: genetic correlations, diffuse coevolution, and constraints on the plant's response to selection.

Science.gov (United States)

Wise, Michael J; Rausher, Mark D

2013-06-01

Although plants are generally attacked by a community of several species of herbivores, relatively little is known about the strength of natural selection for resistance in multiple-herbivore communities-particularly how the strength of selection differs among herbivores that feed on different plant organs or how strongly genetic correlations in resistance affect the evolutionary responses of the plant. Here, we report on a field study measuring natural selection for resistance in a diverse community of herbivores of Solanum carolinense. Using linear phenotypic-selection analyses, we found that directional selection acted to increase resistance to seven species. Selection was strongest to increase resistance to fruit feeders, followed by flower feeders, then leaf feeders. Selection favored a decrease in resistance to a stem borer. Bootstrapping analyses showed that the plant population contained significant genetic variation for each of 14 measured resistance traits and significant covariances in one-third of the pairwise combinations of resistance traits. These genetic covariances reduced the plant's overall predicted evolutionary response for resistance against the herbivore community by about 60%. Diffuse (co)evolution was widespread in this community, and the diffuse interactions had an overwhelmingly constraining (rather than facilitative) effect on the plant's evolution of resistance. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

Crescimento do capim-tifton 85 sob doses de nitrogênio e alturas de corte Growth analysis of Tifton 85 bermudagrass under nitrogen fertilization and plant height

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Odilon Gomes Pereira

2012-01-01

Full Text Available Objetivou-se avaliar os índices de crescimento do capim-tifton 85 adubado com quatro doses de nitrogênio (0, 33, 66, 100, e 133 kg/ha de N e colhido em três alturas da planta (30, 40 e 50 cm. O delineamento experimental utilizado foi inteiramente casualizado em esquema de parcelas subdivididas com três repetições. As doses de nitrogênio corresponderam às parcelas e as alturas na data de corte, às subparcelas. Para todas as variáveis analisadas, a interação dose de N × altura da planta não foi significativa. A taxa assimilatória líquida e a taxa de crescimento relativo do capim-tifton 85 aumentaram com as doses de nitrogênio. A razão de área foliar (RAF decresceu linearmente com a altura de corte das plantas, mas aumentou, também de forma linear, com a dose de nitrogênio. De modo linear, a razão de peso foliar decresceu com a altura de corte da planta forrageira e aumentou com a dose de nitrogênio. A área foliar específica do capim-tifton 85 foi influenciada de forma linear e positiva apenas pela adubação nitrogenada. O índice de área foliar (IAF do capim-tifton 85 aumentou cerca de 0,05 unidade a cada centímetro de incremento na altura de corte das plantas. Houve resposta quadrática da dose de nitrogênio no IAF do capim-tifton 85. O acréscimo na altura do capim-tifton 85 na época do corte reduz a participação de lâmina foliar na forragem. A adubação nitrogenada aumenta a taxa de crescimento do capim-tifton 85, portanto, para assegurar colheita eficiente da forragem, ao aumentar a dose de nitrogênio, é necessário reduzir o intervalo de colheita.The objective this study was to evaluate the growth rates of Tifton 85 bermudagrass under four nitrogen levels (0, 33, 66, 100, and 133 kg/ha N and harvested at three plant heights (30, 40 and 50 cm. The experimental design was completely randomized in a split plot scheme with three replications. Nitrogen rates were set in the plots and plants heights in the

Preliminary Study on Impact Resistances of Fiber Reinforced Concrete Applied Nuclear Power Plants

International Nuclear Information System (INIS)

Jin, Byeong Moo; Kim, Young Jin; Jeon, Se Jin

2013-01-01

Studies to improve the impact resistance depending upon design parameters for fiber reinforced concrete, such as type of fibers and application ratio, are in progress. Authors assessed first the impact resistance of concrete walls depending upon fiber types and missile impact velocities. The safety assessment of nuclear power plants against large civil aircraft crashes have been accomplished for normal concrete and fiber reinforced concretes in this study. Studies on the safety assessments on the nuclear power plants against large civil aircraft crashes are ongoing actively. As a step of evaluating the applicability of fiber reinforced concrete in means of ensuring more structural safety of the nuclear power plants against impact, the impact resistance for the 1% steel and 2% polyamide fiber reinforced concretes have been evaluated. For reactor containment building structures, it seem there is no impact resistance enhancement of fiber reinforced concrete applied to reactor containment building in the cases of impact velocity 150 m/sec considered in this study. However this results from the pre-stressing forces which introduce compressive stresses in concrete wall and dome section of reactor containment building. Nonetheless there may be benefits to apply fiber reinforced concrete to nuclear power plants. For double containment type reactor containment building, the outer structure is a reinforced concrete structure. The impact resistances for non pre-stressed cylindrical reactor containment buildings are enhanced by 23 to 47 % for 2 % polyamide fiber reinforced concretes and 1 % steel fiber reinforced concretes respectively. For other buildings such as auxiliary building, compound building and fuel storage building surrounding the reactor containment building, there are so many reinforced concrete walls which are anticipated some enhancements of impact resistance by using fiber reinforced concretes. And heavier or faster large civil aircraft impacts produce higher

Preliminary Study on Impact Resistances of Fiber Reinforced Concrete Applied Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Jin, Byeong Moo; Kim, Young Jin; Jeon, Se Jin [Daewoo E and C Co. Ltd., Suwon (Korea, Republic of)

2013-10-15

Studies to improve the impact resistance depending upon design parameters for fiber reinforced concrete, such as type of fibers and application ratio, are in progress. Authors assessed first the impact resistance of concrete walls depending upon fiber types and missile impact velocities. The safety assessment of nuclear power plants against large civil aircraft crashes have been accomplished for normal concrete and fiber reinforced concretes in this study. Studies on the safety assessments on the nuclear power plants against large civil aircraft crashes are ongoing actively. As a step of evaluating the applicability of fiber reinforced concrete in means of ensuring more structural safety of the nuclear power plants against impact, the impact resistance for the 1% steel and 2% polyamide fiber reinforced concretes have been evaluated. For reactor containment building structures, it seem there is no impact resistance enhancement of fiber reinforced concrete applied to reactor containment building in the cases of impact velocity 150 m/sec considered in this study. However this results from the pre-stressing forces which introduce compressive stresses in concrete wall and dome section of reactor containment building. Nonetheless there may be benefits to apply fiber reinforced concrete to nuclear power plants. For double containment type reactor containment building, the outer structure is a reinforced concrete structure. The impact resistances for non pre-stressed cylindrical reactor containment buildings are enhanced by 23 to 47 % for 2 % polyamide fiber reinforced concretes and 1 % steel fiber reinforced concretes respectively. For other buildings such as auxiliary building, compound building and fuel storage building surrounding the reactor containment building, there are so many reinforced concrete walls which are anticipated some enhancements of impact resistance by using fiber reinforced concretes. And heavier or faster large civil aircraft impacts produce higher

Localising QTLs for leaf rust resistance and agronomic traits in barley (¤Hordeum vulgare¤ L.)

DEFF Research Database (Denmark)

Kicherer, S.; Backes, G.; Walther, U.

2000-01-01

to leaf rust by means of artificial infection, heading date, plant height and Kernel weight were assessed. For leaf rust resistance, 4 QTLs were localised, that explained 96.1% of the genetic variation. One QTL on chromosome 4H confirmed a position found in another genetic background and one mapped...

Transgenic rice plants expressing a Bacillus subtilis protoporphyrinogen oxidase gene are resistant to diphenyl ether herbicide oxyfluorfen.

Science.gov (United States)

Lee, H J; Lee, S B; Chung, J S; Han, S U; Han, O; Guh, J O; Jeon, J S; An, G; Back, K

2000-06-01

Protoporphyrinogen oxidase (Protox), the penultimate step enzyme of the branch point for the biosynthetic pathway of Chl and hemes, is the target site of action of diphenyl ether (DPE) herbicides. However, Bacillus subtilis Protox is known to be resistant to the herbicides. In order to develop the herbicide-resistant plants, the transgenic rice plants were generated via expression of B. subtilis Protox gene under ubiquitin promoter targeted to the cytoplasm or to the plastid using Agrobacterium-mediated gene transformation. The integration and expression of the transgene were investigated at T0 generation by DNA and RNA blots. Most transgenic rice plants revealed one copy transgene insertion into the rice genome, but some with 3 copies. The expression levels of B. subtilis Protox mRNA appeared to correlate with the copy number. Furthermore, the plastidal transgenic lines exhibited much higher expression of the Protox mRNA than the cytoplasmic transgenic lines. The transgenic plants expressing the B. subtilis Protox gene at T0 generation were found to be resistant to oxyfluorfen when judged by cellular damage with respect to cellular leakage, Chl loss, and lipid peroxidation. The transgenic rice plants targeted to the plastid exhibited higher resistance to the herbicide than the transgenic plants targeted to the cytoplasm. In addition, possible resistance mechanisms in the transgenic plants to DPE herbicides are discussed.

Effect of potassium supply on drought resistance in sorghum: plant growth and macronutrient content

International Nuclear Information System (INIS)

Asgharipour, M.R.; Heidari, M.

2011-01-01

Nowadays, the main limiting natural resource is widely considered to be water. Therefore, research into crop management practices that enhance drought resistance and plant growth when water supply is limited has become increasingly essential. This study was conducted to evaluate the effect of potassium (K) nutritional status on the drought resistance of grain sorghum during 2009. Drought stress by reducing the yield components, especially the number of panicle per plant and one-hundred grain weight reduced grain yield and greatest yield (3499 kg ha/sup -1/) obtained at full irrigation. Potassium sulfate increased grain and biological yield by 28% and 22%, respectively compared to control through improving growth conditions. Drought stress increased the N content, while reduced water availability decreased the K and Na in plant. No K fertilized plants had the lowest leaf K and N and highest Na concentrations. Chlorophyll content increased significantly with increase in K supply and increased frequency of irrigation. Interaction effect of drought stress and potassium sulfate on all studied traits except chlorophyll content was significant and optimum soil K levels protects plants from drought. These observations indicate that adequate K nutrition can improve drought resistance of sorghum. (author)

Influence of neighboring plants on shading stress resistance and recovery of eelgrass, Zostera marina L.

Directory of Open Access Journals (Sweden)

Camilla Gustafsson

Full Text Available Stressful environments may enhance the occurrence of facilitative interspecific interactions between plants. In several regions, Zostera marina occurs in mixed assemblages. However, the potential effects of plant diversity on stress responses and stability properties of Z. marina are poorly understood. We investigated the resistance and recovery of Z. marina subjected to shading (1 mo in a field experiment lasting 2.5 mo. We shaded Z. marina planted in mono- and polycultures (Potamogeton perfoliatus, P. pectinatus, P. filiformis in a factorial design (Shading×Richness at 2 m depth. We estimated the resistance and recovery of Z. marina by measuring four response variables. Polyculture Z. marina lost proportionally less biomass than monocultures, thus having a greater resistance to shading. In contrast, after a 1 mo recovery period, monocultures exhibited higher biomass gain, and a faster recovery than polycultures. Our results suggest that plant species richness enhances the resistance of Z. marina through facilitative mechanisms, while the faster recovery in monocultures is possibly due to interspecific competition. Our results highlight the need of a much better understanding of the effects of interspecific interactions on ecosystem processes in mixed seagrass meadows, and the preservation of diverse plant assemblages to maintain ecosystem functioning.

Dlf1, a WRKY transcription factor, is involved in the control of flowering time and plant height in rice.

Directory of Open Access Journals (Sweden)

Yuhui Cai

Full Text Available Flowering time and plant height are important agronomic traits for crop production. In this study, we characterized a semi-dwarf and late flowering (dlf1 mutation of rice that has pleiotropic effects on these traits. The dlf1 mutation was caused by a T-DNA insertion and the cloned Dlf1 gene was found to encode a WRKY transcription factor (OsWRKY11. The dlf1 mutant contains a T-DNA insertion at the promoter region, leading to enhanced accumulation of Dlf1 transcripts, resulting in a semidominant mutation. The dlf1 mutation suppressed the transcription of Ehd2/RID1/OsId1 and its downstream flowering-time genes including Hd1, Ehd1 and Hd3a under both long-day (LD and short-day (SD conditions. Knock-down of Dlf1 expression exhibited early flowering at LD condition related to the wild-type plants. Accumulation of Dlf1 mRNA was observed in most tissues, and two splicing forms of Dlf1 cDNAs were obtained (OsWRKY11.1 and OsWRKY11.2. These two proteins showed transactivation activity in yeast cells. Dlf1 protein was found to be localized in the nucleus. Enhanced expression of OsWRKY11.2 or its 5' truncated gene showed similar phenotypes to the dlf1 mutant, suggesting that it might function as a negative regulator. We conclude that Dlf1 acts as a transactivator to downregulate Ehd2/RID1/OsId1 in the signal transduction pathway of flowering and plays an important role in the regulation of plant height in rice.

Gibberellin homeostasis and plant height control by EUI and a role for gibberellin in root gravity responses in rice.

Science.gov (United States)

Zhang, Yingying; Zhu, Yongyou; Peng, Yu; Yan, Dawei; Li, Qun; Wang, Jianjun; Wang, Linyou; He, Zuhua

2008-03-01

The rice Eui (ELONGATED UPPERMOST INTERNODE) gene encodes a cytochrome P450 monooxygenase that deactivates bioactive gibberellins (GAs). In this study, we investigated controlled expression of the Eui gene and its role in plant development. We found that Eui was differentially induced by exogenous GAs and that the Eui promoter had the highest activity in the vascular bundles. The eui mutant was defective in starch granule development in root caps and Eui overexpression enhanced starch granule generation and gravity responses, revealing a role for GA in root starch granule development and gravity responses. Experiments using embryoless half-seeds revealed that RAmy1A and GAmyb were highly upregulated in eui aleurone cells in the absence of exogenous GA. In addition, the GA biosynthesis genes GA3ox1 and GA20ox2 were downregulated and GA2ox1 was upregulated in eui seedlings. These results indicate that EUI is involved in GA homeostasis, not only in the internodes at the heading stage, but also in the seedling stage, roots and seeds. Disturbing GA homeostasis affected the expression of the GA signaling genes GID1 (GIBBERELLIN INSENSITIVE DWARF 1), GID2 and SLR1. Transgenic RNA interference of the Eui gene effectively increased plant height and improved heading performance. By contrast, the ectopic expression of Eui under the promoters of the rice GA biosynthesis genes GA3ox2 and GA20ox2 significantly reduced plant height. These results demonstrate that a slight increase in Eui expression could dramatically change rice morphology, indicating the practical application of the Eui gene in rice molecular breeding for a high yield potential.

Plant resistance in sorghums to the sugarcane aphid Melanaphis sacchari (Hemiptera: Aphididae)

Science.gov (United States)

We evaluated ten sorghum lines that were near or in commercial release with the intent of identifying phenotypic expression of host-plant resistance to the sugarcane aphid. Two of the ten entries OL2042 and SP7715 expressed a high degree of resistance to the sugarcane aphid with damage ratings <3.0...

The association between adult attained height and sitting height with mortality in the European Prospective Investigation into Cancer and Nutrition (EPIC.

Directory of Open Access Journals (Sweden)

Norie Sawada

Full Text Available Adult height and sitting height may reflect genetic and environmental factors, including early life nutrition, physical and social environments. Previous studies have reported divergent associations for height and chronic disease mortality, with positive associations observed for cancer mortality but inverse associations for circulatory disease mortality. Sitting height might be more strongly associated with insulin resistance; however, data on sitting height and mortality is sparse. Using the European Prospective Investigation into Cancer and Nutrition study, a prospective cohort of 409,748 individuals, we examined adult height and sitting height in relation to all-cause and cause-specific mortality. Height was measured in the majority of participants; sitting height was measured in ~253,000 participants. During an average of 12.5 years of follow-up, 29,810 deaths (11,931 from cancer and 7,346 from circulatory disease were identified. Hazard ratios (HR with 95% confidence intervals (CI for death were calculated using multivariable Cox regression within quintiles of height. Height was positively associated with cancer mortality (men: HRQ5 vs. Q1 = 1.11, 95%CI = 1.00-1.24; women: HRQ5 vs. Q1 = 1.17, 95%CI = 1.07-1.28. In contrast, height was inversely associated with circulatory disease mortality (men: HRQ5 vs. Q1 = 0.63, 95%CI = 0.56-0.71; women: HRQ5 vs. Q1 = 0.81, 95%CI = 0.70-0.93. Although sitting height was not associated with cancer mortality, it was inversely associated with circulatory disease (men: HRQ5 vs. Q1 = 0.64, 95%CI = 0.55-0.75; women: HRQ5 vs. Q1 = 0.60, 95%CI = 0.49-0.74 and respiratory disease mortality (men: HRQ5 vs. Q1 = 0.45, 95%CI = 0.28-0.71; women: HRQ5 vs. Q1 = 0.60, 95%CI = 0.40-0.89. We observed opposing effects of height on cancer and circulatory disease mortality. Sitting height was inversely associated with circulatory disease and respiratory disease mortality.

Influence of plant roots on electrical resistivity measurements of cultivated soil columns

Science.gov (United States)

Maloteau, Sophie; Blanchy, Guillaume; Javaux, Mathieu; Garré, Sarah

2016-04-01

Electrical resistivity methods have been widely used for the last 40 years in many fields: groundwater investigation, soil and water pollution, engineering application for subsurface surveys, etc. Many factors can influence the electrical resistivity of a media, and thus influence the ERT measurements. Among those factors, it is known that plant roots affect bulk electrical resistivity. However, this impact is not yet well understood. The goals of this experiment are to quantify the effect of plant roots on electrical resistivity of the soil subsurface and to map a plant roots system in space and time with ERT technique in a soil column. For this research, it is assumed that roots system affect the electrical properties of the rhizosphere. Indeed the root activity (by transporting ions, releasing exudates, changing the soil structure,…) will modify the rhizosphere electrical conductivity (Lobet G. et al, 2013). This experiment is included in a bigger research project about the influence of roots system on geophysics measurements. Measurements are made on cylinders of 45 cm high and a diameter of 20 cm, filled with saturated loam on which seeds of Brachypodium distachyon (L.) Beauv. are sowed. Columns are equipped with electrodes, TDR probes and temperature sensors. Experiments are conducted at Gembloux Agro-Bio Tech, in a growing chamber with controlled conditions: temperature of the air is fixed to 20° C, photoperiod is equal to 14 hours, photosynthetically active radiation is equal to 200 μmol m-2s-1, and air relative humidity is fixed to 80 %. Columns are fully saturated the first day of the measurements duration then no more irrigation is done till the end of the experiment. The poster will report the first results analysis of the electrical resistivity distribution in the soil columns through space and time. These results will be discussed according to the plant development and other controlled factors. Water content of the soil will also be detailed

Seismic resistance design of nuclear power plant building structures in Japan

International Nuclear Information System (INIS)

Kitano, Takehito

1997-01-01

Japan is one of the countries where earthquakes occur most frequently in the world and has incurred a lot of disasters in the past. Therefore, the seismic resistance design of a nuclear power plant plays a very important role in Japan. This report describes the general method of seismic resistance design of a nuclear power plant giving examples of PWR and BWR type reactor buildings in Japan. Nuclear facilities are classified into three seismic classes and is designed according to the corresponding seismic class in Japan. Concerning reactor buildings, the short-term allowable stress design is applied for the S1 seismic load and it is confirmed that the structures have a safety margin against the S2 seismic load. (J.P.N.)

Seismic resistance design of nuclear power plant building structures in Japan

Energy Technology Data Exchange (ETDEWEB)

Kitano, Takehito [Kansai Electric Power Co., Inc., Osaka (Japan)

1997-03-01

Japan is one of the countries where earthquakes occur most frequently in the world and has incurred a lot of disasters in the past. Therefore, the seismic resistance design of a nuclear power plant plays a very important role in Japan. This report describes the general method of seismic resistance design of a nuclear power plant giving examples of PWR and BWR type reactor buildings in Japan. Nuclear facilities are classified into three seismic classes and is designed according to the corresponding seismic class in Japan. Concerning reactor buildings, the short-term allowable stress design is applied for the S1 seismic load and it is confirmed that the structures have a safety margin against the S2 seismic load. (J.P.N.)

[Expression of plant antimicrobial peptide pro-SmAMP2 gene increases resistance of transgenic potato plants to Alternaria and Fusarium pathogens].

Science.gov (United States)

Vetchinkina, E M; Komakhina, V V; Vysotskii, D A; Zaitsev, D V; Smirnov, A N; Babakov, A V; Komakhin, R A

2016-09-01

The chickweed (Stellaria media L.) pro-SmAMP2 gene encodes the hevein-like peptides that have in vitro antimicrobial activity against certain harmful microorganisms. These peptides play an important role in protecting the chickweed plants from infection, and the pro-SmAMP2 gene was previously used to protect transgenic tobacco and Arabidopsis plants from phytopathogens. In this study, the pro-SmAMP2 gene under control of viral CaMV35S promoter or under control of its own pro-SmAMP2 promoter was transformed into cultivated potato plants of two cultivars, differing in the resistance to Alternaria: Yubiley Zhukova (resistant) and Skoroplodny (susceptible). With the help of quantitative real-time PCR, it was demonstrated that transgenic potato plants expressed the pro-SmAMP2 gene under control of both promoters at the level comparable to or exceeding the level of the potato actin gene. Assessment of the immune status of the transformants demonstrated that expression of antimicrobial peptide pro-SmAMP2 gene was able to increase the resistance to a complex of Alternaria sp. and Fusarium sp. phytopathogens only in potato plants of the Yubiley Zhukova cultivar. The possible role of the pro-SmAMP2 products in protecting potatoes from Alternaria sp. and Fusarium sp. is discussed.

The agricultural use of water treatment plant sludge: pathogens and antibiotic resistance

Directory of Open Access Journals (Sweden)

Ignacio Nadal Rocamora

2015-12-01

Full Text Available The use of water treatment plant sludge to restore degraded soils is customary agricultural practice, but it could be dangerous from the point of view of both health and the environment. A transient increase of either pathogenic or indicator microbial populations, whose persistence in time is variable and attributed to the characteristics of the soil (types of materials in the soil, any amendments (origin and treatments it has undergone or the weather (humidity and temperature mainly, has often been detected in soils treated with this kind of waste. Given their origin, water treatment plant sludges could lead to the transmission of a pathogens and b antibiotic-resistant microorganisms to human beings through the food chain and cause the spreading of antibiotic resistances as a result of their increase and persistence in the soil for variable periods of time. However, Spanish legislation regulating the use of sludges in the farming industry is based on a very restricted microbiological criterion. Thus, we believe better parameters should be established to appropriately inform of the state of health of soils treated with water treatment plant sludge, including aspects which are not presently assessed such as antibiotic resistance.

Attenuation of the jasmonate burst, plant defensive traits, and resistance to specialist monarch caterpillars on shaded common milkweed (Asclepias syriaca).

Science.gov (United States)

Agrawal, Anurag A; Kearney, Emily E; Hastings, Amy P; Ramsey, Trey E

2012-07-01

Plant responses to herbivory and light competition are often in opposing directions, posing a potential conflict for plants experiencing both stresses. For sun-adapted species, growing in shade typically makes plants more constitutively susceptible to herbivores via reduced structural and chemical resistance traits. Nonetheless, the impact of light environment on induced resistance has been less well-studied, especially in field experiments that link physiological mechanisms to ecological outcomes. Accordingly, we studied induced resistance of common milkweed (Asclepias syriaca, a sun-adapted plant), and linked hormonal responses, resistance traits, and performance of specialist monarch caterpillars (Danaus plexippus) in varying light environments. In natural populations, plants growing under forest-edge shade showed reduced levels of resistance traits (lower leaf toughness, cardenolides, and trichomes) and enhanced light-capture traits (higher specific leaf area, larger leaves, and lower carbon-to-nitrogen ratio) compared to paired plants in full sun. In a field experiment repeated over two years, only milkweeds growing in full sun exhibited induced resistance to monarchs, whereas plants growing in shade were constitutively more susceptible and did not induce resistance. In a more controlled field experiment, plant hormones were higher in the sun (jasmonic acid, salicylic acid, abscisic acid, indole acidic acid) and were induced by herbivory (jasmonic acid and abscisic acid). In particular, the jasmonate burst following herbivory was halved in plants raised in shaded habitats, and this correspondingly reduced latex induction (but not cardenolide induction). Thus, we provide a mechanistic basis for the attenuation of induced plant resistance in low resource environments. Additionally, there appears to be specificity in these interactions, with light-mediated impacts on jasmonate-induction being stronger for latex exudation than cardenolides.

Serious complications in experiments in which UV doses are effected by using different lamp heights.

Science.gov (United States)

Flint, Stephan D; Ryel, Ronald J; Hudelson, Timothy J; Caldwell, Martyn M

2009-10-06

Many experiments examining plant responses to enhanced ultraviolet-B radiation (280-315nm) simply compare an enhanced UV-B treatment with ambient UV-B (or no UV-B radiation in most greenhouse and controlled-environment studies). Some more detailed experiments utilize multiple levels of UV-B radiation. A number of different techniques have been used to adjust the UV dose. One common technique is to place racks of fluorescent UV-emitting lamps at different heights above the plant canopy. However, the lamps and associated support structure cast shadows on the plant bed below. We calculated one example of the sequence of shade intervals for two common heights of lamp racks and show the patterns and duration of shade which the plants receive is distributed differently over the course of the day for different heights of the lamp racks. We also conducted a greenhouse experiment with plants (canola, sunflower and maize) grown under unenergized lamp racks suspended at the same two heights above the canopy. Growth characteristics differed in unpredictable ways between plants grown under the two heights of lamp racks. These differences could enhance or obscure potential UV-B effects. Also, differences in leaf mass per unit foliage area, which were observed in this experiment, could contribute to differences in plant UV-B sensitivity. We recommend the use of other techniques for achieving multiple doses of UV-B radiation. These range from simple and inexpensive approaches (e.g., wrapping individual fluorescent tubes in layers of a neutral-density filter such as cheese cloth) to more technical and expensive alternatives (e.g., electronically modulated lamp control systems). These choices should be determined according to the goals of the particular experiment.

Resistance of solanum species to phytophthora infestans evaluated in the detached-leaf and whole-plant assays

International Nuclear Information System (INIS)

Akhtar, K.P.; Saleem, M.Y.; Asghar, M.

2012-01-01

The reaction of 82 tomato genotypes belonging to 8 Solanum and a Lycopersicon species against Phytophthora infestans causing late blight was determined using detached-leaf and whole-plant assays. None of the test genotypes was immune or highly resistant. Of the 82 commercial and wild genotypes only TMS-2 (male-sterile and characterized by indeterminate growth) belonging to Lycopersicon esculentum was resistant with severity index of 2.4 in the detached-leaf assay on 0-5 scale (where 5 was highly susceptible) and percent disease index (%DI) of 23.3% under the whole-plant assay. Among the remaining genotypes, 41 were susceptible and 40 were highly susceptible under the detached-leaf assay, while 18 were susceptible and 63 were highly susceptible under the whole-plant assay. However, there was a significant difference in %DI for genotypes under the whole-plant assay. The response of whole-plants to inoculation with P. infestans in the detached-leaf assay was similar in all cases. The overall screening results indicate that TMS-2 is a good source of resistance and it can be useful for the development of tomato hybrid cultivars resistant to late blight. (author)

A macroecological analysis of SERA derived forest heights and implications for forest volume remote sensing.

Science.gov (United States)

Brolly, Matthew; Woodhouse, Iain H; Niklas, Karl J; Hammond, Sean T

2012-01-01

Individual trees have been shown to exhibit strong relationships between DBH, height and volume. Often such studies are cited as justification for forest volume or standing biomass estimation through remote sensing. With resolution of common satellite remote sensing systems generally too low to resolve individuals, and a need for larger coverage, these systems rely on descriptive heights, which account for tree collections in forests. For remote sensing and allometric applications, this height is not entirely understood in terms of its location. Here, a forest growth model (SERA) analyzes forest canopy height relationships with forest wood volume. Maximum height, mean, H₁₀₀, and Lorey's height are examined for variability under plant number density, resource and species. Our findings, shown to be allometrically consistent with empirical measurements for forested communities world-wide, are analyzed for implications to forest remote sensing techniques such as LiDAR and RADAR. Traditional forestry measures of maximum height, and to a lesser extent H₁₀₀ and Lorey's, exhibit little consistent correlation with forest volume across modeled conditions. The implication is that using forest height to infer volume or biomass from remote sensing requires species and community behavioral information to infer accurate estimates using height alone. SERA predicts mean height to provide the most consistent relationship with volume of the height classifications studied and overall across forest variations. This prediction agrees with empirical data collected from conifer and angiosperm forests with plant densities ranging between 10²-10⁶ plants/hectare and heights 6-49 m. Height classifications investigated are potentially linked to radar scattering centers with implications for allometry. These findings may be used to advance forest biomass estimation accuracy through remote sensing. Furthermore, Lorey's height with its specific relationship to remote sensing

Following the genes that make resistant plants: shared tools for breeding and pathology

Science.gov (United States)

Although plant pathology and breeding are distinct disciplines with unique perspectives, they frequently share a common goal: that of identifying and understanding durable resistance, the kind of resistance that will not be overcome quickly and will remain effective against a wide array of isolates....

Characterization and comparison of transgenic Artemisia annua GYR and wild-type NON-GYR plants in an environmental release trial.

Science.gov (United States)

Liu, H; Wu, G G; Wang, J B; Wu, X; Bai, L; Jiang, W; Lv, B B; Pan, A H; Jia, J W; Li, P; Zhao, K; Jiang, L X; Tang, X M

2016-08-26

The anti-malarial drug, artemisinin, is quite expensive as a result of its slow content in Artemisia annua. Recent investigations have suggested that genetic engineering of A. annua is a promising approach to improve the yield of artemisinin. In this study, the transgenic A. annua strain GYR, which has high artemisinin content, was evaluated in an environmental release trial. First, GYR plants were compared with the wild-type variety NON-GYR, with regard to phenotypic characters (plant height, crown width, stem diameter, germination rate, leaf dry weight, 1000-seed weight, leave shape). Second, stress resistance in the two varieties (salt, drought, herbicide, and cold resistance) was evaluated under different experimental conditions. Finally, gene flow was estimated. The results indicated that there were significant differences in several agronomic traits (plant height, stem diameter, and leave dry weight) between the transgenic GYR and NON-GYR plants. Salt stress in transgenic and control plants was similar, except under high NaCl concentrations (1.6%, w/w). Leaf water, proline, and MDA content (increased significantly) were significantly different. Transgenic A. annua GYR plants did not grow better than NON-GYR plants with respect to drought and herbicide resistance. The two varieties maintained vitality through the winter. Third, gene flow was studied in an environmental risk trial for transgenic GYR. The maximum gene flow frequency was 2.5%, while the maximum gene flow distance was 24.4 m; gene flow was not detected at 29.2 m at any direction. Our findings may provide an opportunity for risk assessment in future commercialization of transgenic A. annua varieties.

Eukaryotic translation initiation factor 2B-beta (eIF2Bβ), a new class of plant virus resistance gene.

Science.gov (United States)

Shopan, Jannat; Mou, Haipeng; Zhang, Lili; Zhang, Changtong; Ma, Weiwei; Walsh, John A; Hu, Zhongyuan; Yang, Jinghua; Zhang, Mingfang

2017-06-01

Recessive resistances to plant viruses in the Potyvirus genus have been found to be based on mutations in the plant eukaryotic translation initiation factors, eIF4E and eIF4G or their isoforms. Here we report that natural, monogenic recessive resistance to the Potyvirus Turnip mosaic virus (TuMV) has been found in a number of mustard (Brassica juncea) accessions. Bulked segregant analysis and sequencing of resistant and susceptible plant lines indicated the resistance is controlled by a single recessive gene, recessive TuMV resistance 03 (retr03), an allele of the eukaryotic translation initiation factor 2B-beta (eIF2Bβ). Silencing of eIF2Bβ in a TuMV-susceptible mustard plant line and expression of eIF2Bβ from a TuMV-susceptible line in a TuMV-resistant mustard plant line confirmed the new resistance mechanism. A functional copy of a specific allele of eIF2Bβ is required for efficient TuMV infection. eIF2Bβ represents a new class of virus resistance gene conferring resistance to any pathogen. eIF2B acts as a guanine nucleotide exchange factor (GEF) for its GTP-binding protein partner eIF2 via interaction with eIF2·GTP at an early step in translation initiation. Further genotyping indicated that a single non-synonymous substitution (A120G) in the N-terminal region of eIF2Bβ was responsible for the TuMV resistance. A reproducible marker has been developed, facilitating marker-assisted selection for TuMV resistance in B. juncea. Our findings provide a new target for seeking natural resistance to potyviruses and new opportunities for the control of potyviruses using genome editing techniques targeted on eIF2Bβ. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

Fear of heights and visual height intolerance.

Science.gov (United States)

Brandt, Thomas; Huppert, Doreen

2014-02-01

The aim of this review is, first, to cover the different aspects of visual height intolerance such as historical descriptions, definition of terms, phenomenology of the condition, neurophysiological control of gaze, stance and locomotion, and therapy, and, second, to identify warranted epidemiological and experimental studies. Vivid descriptions of fear of heights can be found in ancient texts from the Greek, Roman, and Chinese classics. The life-time prevalence of visual height intolerance is as high as 28% in the general population, and about 50% of those who are susceptible report an impact on quality of life. When exposed to heights, visual exploration by eye and head movements is restricted, and the velocity of locomotion is reduced. Therapy for fear of heights is dominated by the behavioral techniques applied during real or virtual reality exposure. Their efficacy might be facilitated by the administration of D-cycloserine or glucocorticoids. Visual height intolerance has a considerable impact on daily life and interpersonal interactions. It is much more frequent than fear of heights, which is defined as an environmental subtype of a specific phobia. There is certainly a continuum stretching from acrophobia to a less-pronounced visual height intolerance, to which the categorical distinction of a specific phobia does not apply.

Poppy Crop Height and Capsule Volume Estimation from a Single UAS Flight

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Faheem Iqbal

2017-06-01

Full Text Available The objective of this study was to estimate poppy plant height and capsule volume with remote sensing using an Unmanned Aircraft System (UAS. Data were obtained from field measurements and UAS flights over two poppy crops at Cambridge and Cressy in Tasmania. Imagery acquired from the UAS was used to produce dense point clouds using structure from motion (SfM and multi-view stereopsis (MVS techniques. Dense point clouds were used to generate a digital surface model (DSM and orthophoto mosaic. An RGB index was derived from the orthophoto to extract the bare ground spaces. This bare ground space mask was used to filter the points on the ground, and a digital terrain model (DTM was interpolated from these points. Plant height values were estimated by subtracting the DSM and DTM to generate a Crop Height Model (CHM. UAS-derived plant height (PH and field measured PH in Cambridge were strongly correlated with R2 values ranging from 0.93 to 0.97 for Transect 1 and Transect 2, respectively, while at Cressy results from a single flight provided R2 of 0.97. Therefore, the proposed method can be considered an important step towards crop surface model (CSM generation from a single UAS flight in situations where a bare ground DTM is unavailable. High correlations were found between UAS-derived PH and poppy capsule volume (CV at capsule formation stage (R2 0.74, with relative error of 19.62%. Results illustrate that plant height can be reliably estimated for poppy crops based on a single UAS flight and can be used to predict opium capsule volume at capsule formation stage.

Evolving ideas about genetics underlying insect virulence to plant resistance in rice-brown planthopper interactions.

Science.gov (United States)

Kobayashi, Tetsuya

2016-01-01

Many plant-parasite interactions that include major plant resistance genes have subsequently been shown to exhibit features of gene-for-gene interactions between plant Resistance genes and parasite Avirulence genes. The brown planthopper (BPH) Nilaparvata lugens is an important pest of rice (Oryza sativa). Historically, major Resistance genes have played an important role in agriculture. As is common in gene-for-gene interactions, evolution of BPH virulence compromises the effectiveness of singly-deployed resistance genes. It is therefore surprising that laboratory studies of BPH have supported the conclusion that virulence is conferred by changes in many genes rather than a change in a single gene, as is proposed by the gene-for-gene model. Here we review the behaviour, physiology and genetics of the BPH in the context of host plant resistance. A problem for genetic understanding has been the use of various insect populations that differ in frequencies of virulent genotypes. We show that the previously proposed polygenic inheritance of BPH virulence can be explained by the heterogeneity of parental populations. Genetic mapping of Avirulence genes indicates that virulence is a monogenic trait. These evolving concepts, which have brought the gene-for-gene model back into the picture, are accelerating our understanding of rice-BPH interactions at the molecular level. Copyright © 2015 Elsevier Ltd. All rights reserved.

Low crop plant population densities promote pollen-mediated gene flow in spring wheat (Triticum aestivum L.).

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Willenborg, Christian J; Brûlé-Babel, Anita L; Van Acker, Rene C

2009-12-01

Transgenic wheat is currently being field tested with the intent of eventual commercialization. The development of wheat genotypes with novel traits has raised concerns regarding the presence of volunteer wheat populations and the role they may play in facilitating transgene movement. Here, we report the results of a field experiment that investigated the potential of spring wheat plant population density and crop height to minimize gene flow from a herbicide-resistant (HR) volunteer population to a non-HR crop. Pollen-mediated gene flow (PMGF) between the HR volunteer wheat population and four conventional spring wheat genotypes varying in height was assessed over a range of plant population densities. Natural hybridization events between the two cultivars were detected by phenotypically scoring plants in F(1) populations followed by verification with Mendelian segregation ratios in the F(1:2) families. PMGF was strongly associated with crop yield components, but showed no association with flowering synchrony. Maximum observed PMGF was always less than 0.6%, regardless of crop height and density. The frequency of PMGF in spring wheat decreased exponentially with increasing plant population density, but showed no dependence on either crop genotype or height. However, increasing plant densities beyond the recommended planting rate of 300 cropped wheat plants m(-2) provided no obvious benefit to reducing PMGF. Nevertheless, our results demonstrate a critical plant density of 175-200 cropped wheat plants m(-2) below which PMGF frequencies rise exponentially with decreasing plant density. These results will be useful in the development of mechanistic models and best management practices that collectively facilitate the coexistence of transgenic and nontransgenic wheat crops.

Appraisal of wheat germplasm for adult plant resistance against stripe rust

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Saleem Kamran

2015-12-01

Full Text Available The resurgence of wheat stripe rust is of great concern for world food security. Owing to resistance breakdown and the appearance of new virulent high-temperature adapted races of Puccinia striiformis f. sp. tritici (Pst, many high yielding commercial varieties in the country lost their yield potential. Searching for new sources of resistance is the best approach to mitigate the problem. Quantitative resistance (partial or adult plant or durable resistance is reported to be more stable than race specific resistance. In the current perusal, a repertoire of 57 promising wheat lines along with the KLcheck line Morocco, developed through hybridisation and selection of local and international lines with International Maize and Wheat Improvement Center (CIMMYT origin, were evaluated under natural field conditions at Nuclear Institute for Agriculture and Biology (NIAB during the 2012−2013 and 2013−2014 time periods. Final rust severity (FRS, the area under the rust progress curve (AURPC, the relative area under the rust progress curve (rAURPC, and the coefficient of infection (CI were unraveled to infer the level of quantitative resistance. Final rust severity was recorded when the susceptible check exhibited 100% severity. There were 21 lines which were immune (no disease, 16 which were resistant, five moderately resistant, two resistant-to-moderately resistant, one moderately resistant-to-moderately susceptible, 5 moderately susceptible-to-susceptible, one moderately susceptible, and six exhibited a susceptible response. Nevertheless, 51 lines exhibited a high level of partial resistance while the three lines, NW-5-1212-1, NW-7-30-1, and NW-7-5 all showed a moderate level of partial resistance based on FRS, while 54 lines, on the basis of AURPC and rAURPC, were identified as conferring a high level of partial resistance. Moreover, adult plant resistance was conferred by 47 wheat lines, based on CI value. It was striking that, 13 immune lines

Pyramids of QTLs enhance host-plant resistance and Bt-mediated resistance to leaf-chewing insects in soybean.

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Ortega, María A; All, John N; Boerma, H Roger; Parrott, Wayne A

2016-04-01

QTL-M and QTL-E enhance soybean resistance to insects. Pyramiding these QTLs with cry1Ac increases protection against Bt-tolerant pests, presenting an opportunity to effectively deploy Bt with host-plant resistance genes. Plant resistance to leaf-chewing insects minimizes the need for insecticide applications, reducing crop production costs and pesticide concerns. In soybean [Glycine max (L.) Merr.], resistance to a broad range of leaf-chewing insects is found in PI 229358 and PI 227687. PI 229358's resistance is conferred by three quantitative trait loci (QTLs): M, G, and H. PI 227687's resistance is conferred by QTL-E. The letters indicate the soybean Linkage groups (LGs) on which the QTLs are located. This study aimed to determine if pyramiding PI 229358 and PI 227687 QTLs would enhance soybean resistance to leaf-chewing insects, and if pyramiding these QTLs with Bt (cry1Ac) enhances resistance against Bt-tolerant pests. The near-isogenic lines (NILs): Benning(ME), Benning(MGHE), and Benning(ME+cry1Ac) were developed. Benning(ME) and Benning(MGHE) were evaluated in detached-leaf and greenhouse assays with soybean looper [SBL, Chrysodeixis includens (Walker)], corn earworm [CEW, Helicoverpa zea (Boddie)], fall armyworm [FAW, Spodoptera frugiperda (J.E. Smith)], and velvetbean caterpillar [VBC, Anticarsia gemmatalis (Hübner)]; and in field-cage assays with SBL. Benning(ME+cry1Ac) was tested in detached-leaf assays against SBL, VBC, and Southern armyworm [SAW, Spodoptera eridania (Cramer)]. In the detached-leaf assay, Benning(ME) showed the strongest antibiosis against CEW, FAW, and VBC. In field-cage conditions, Benning(ME) and Benning(MGHE) suffered 61 % less defoliation than Benning. Benning(ME+cry1Ac) was more resistant than Benning(ME) and Benning (cry1Ac) against SBL and SAW. Agriculturally relevant levels of resistance in soybean can be achieved with just two loci, QTL-M and QTL-E. ME+cry1Ac could present an opportunity to protect the durability of Bt

Transgenic rice plants harboring an introduced potato proteinase inhibitor II gene are insect resistant.

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Duan, X; Li, X; Xue, Q; Abo-el-Saad, M; Xu, D; Wu, R

1996-04-01

We introduced the potato proteinase inhibitor II (PINII) gene (pin2) into several Japonica rice varieties, and regenerated a large number of transgenic rice plants. Wound-inducible expression of the pin2 gene driven by its own promoter, together with the first intron of the rice actin 1 gene (act1), resulted in high-level accumulation of the PINII protein in the transgenic plants. The introduced pin2 gene was stably inherited in the second, third, and fourth generations, as shown by molecular analyses. Based on data from the molecular analyses, several homozygous transgenic lines were obtained. Bioassay for insect resistance with the fifth-generation transgenic rice plants showed that transgenic rice plants had increased resistance to a major rice insect pest, pink stem borer (Sesamia inferens). Thus, introduction of an insecticidal proteinase inhibitor gene into cereal plants can be used as a general strategy for control of insect pests.

Production of Basella plants resistant to rust by irradiation of seeds and vegetative tissue

International Nuclear Information System (INIS)

Makambila, C.

1997-01-01

Basella is classified in the family Chenopodiaceae or Basellaceae. Also known as African spinach, this plant is consumed in Central Africa and several other African countries. There are two types of varieties grown in Congo: i. a local variety characterized by red leaves and stalks in which the principal way of propagation is from cuttings; ii. a group of varieties which have green or purple leaves and stalks. These varieties are called Basella alba and Basella rubra. These varieties have sexual reproduction. Among the two groups of varieties, the local variety is propagated vegetatively but is resistant to rust, while varieties with green leaves or with purple leaves (B. alba and B. rubra) that are propagated from seed are susceptible to rust. Since hybrid cannot be made by conventional crossing, the following procedures have been adopted to produce plants with disease tolerance: 1. production of resistant variants by irradiation of Basella alba seeds with Cesium 137; 2. production of resistant variants by irradiation of vegetative tissues obtained by culture of meristematic cells of B alba; and 3. obtaining resistant plants through somaclonal variation. 1 tab

Production of Basella plants resistant to rust by irradiation of seeds and vegetative tissue

Energy Technology Data Exchange (ETDEWEB)

Makambila, C [Laboratory of Phytopathology, Faculty of Sciences, Univ. of Brazzaville, Brazzaville (Congo)

1997-12-01

Basella is classified in the family Chenopodiaceae or Basellaceae. Also known as African spinach, this plant is consumed in Central Africa and several other African countries. There are two types of varieties grown in Congo: i. a local variety characterized by red leaves and stalks in which the principal way of propagation is from cuttings; ii. a group of varieties which have green or purple leaves and stalks. These varieties are called Basella alba and Basella rubra. These varieties have sexual reproduction. Among the two groups of varieties, the local variety is propagated vegetatively but is resistant to rust, while varieties with green leaves or with purple leaves (B. alba and B. rubra) that are propagated from seed are susceptible to rust. Since hybrid cannot be made by conventional crossing, the following procedures have been adopted to produce plants with disease tolerance: 1. production of resistant variants by irradiation of Basella alba seeds with Cesium 137; 2. production of resistant variants by irradiation of vegetative tissues obtained by culture of meristematic cells of B alba; and 3. obtaining resistant plants through somaclonal variation. 1 tab.

Fitness Outcomes Related to Glyphosate Resistance in Kochia (Kochia scoparia: What Life History Stage to Examine?

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Omobolanle Adewale Osipitan

2017-06-01

Full Text Available A fast-spreading weed, kochia (Kochia scoparia, has developed resistance to the widely-used herbicide, glyphosate. Understanding the relationship between the occurrence of glyphosate resistance caused by multiple EPSPS gene copies and kochia fitness may suggest a more effective way of controlling kochia. A study was conducted to assess fitness cost of glyphosate resistance compared to susceptibility in kochia populations at different life history stages, that is rate of seed germination, increase in plant height, days to flowering, biomass accumulation at maturity, and fecundity. Six kochia populations from Scott, Finney, Thomas, Phillips, Wallace, and Wichita counties in western Kansas were characterized for resistance to field-use rate of glyphosate and with an in vivo shikimate accumulation assay. Seed germination was determined in growth chambers at three constant temperatures (5, 10, and 15 C while vegetative growth and fecundity responses were evaluated in a field study using a target-neighborhood competition design in 2014 and 2015. One target plant from each of the six kochia populations was surrounded by neighboring kochia densities equivalent to 10 (low, 35 (moderate, or 70 (high kochia plants m−2. In 2015, neighboring corn densities equivalent to 10 and 35 plants m−2 were also evaluated. Treatments were arranged in a randomized complete block design with at least 7 replications. Three kochia populations were classified as glyphosate-resistant (GR [Scott (SC-R, Finney (FN-R, and Thomas (TH-R] and three populations were classified as glyphosate-susceptible (GS [Phillips (PH-S, Wallace (WA-S and Wichita (WI-S]. Of the life history stages measured, fitness differences between the GR and GS kochia populations were consistently found in their germination characteristics. The GR kochia showed reduced seed longevity, slower germination rate, and less total germination than the GS kochia. In the field, increases in plant height, biomass

Development of abiotic-stress resistant warm season trufgrasses by proton-beam irradiation

Energy Technology Data Exchange (ETDEWEB)

Seo, Y. W.; Kim, J. Y.; Jeong, S. H. [Korea Univ., Seoul (Korea, Republic of)

2007-04-15

The direct use of mutation is a valuable approach to generate genetic variation in crop species by altering agronomically useful major traits. The proton beam, as a mutagen, was applied to improve resistance traits of Zoysia grass under various abiotic stresses. Proton beam was irradiated to mature dry seeds of Zenith (Zoysia grass), which is well-adapted to Korean climate, using a proton- accelerator with seven different doses (50, 100, 150, 200, 250, 300, 400 Gy). Individual seedling of M1 plant was transplanted from the seed bed and allowed to reach appropriate plant mass. Clones that showed superior growth were chosen and transplanted to pots for further clone propagation and field evaluation. Growth characteristics of turfgrass, such as plant height, leaf length, leaf width, number of tiller were evaluated ninety days after sowing. Although large variation within each dose, noticeable differences were found among different irradiated doses. Most of the mutant clones derived from the irradiation treatment showed more vigorous growth than the control plants. RAPD (Random Amplified Polymorphic DNA) and AFLP (Amplified Fragment Length Polymorphism) methods were conducted to analyze genomic variations associated with proton beam irradiation. In order to establish selection criteria for selection of salt-stress resistance plants, an in vitro method that is able to select salt-stress resistant mutants in liquid media without ambient disturbances. Total 647 predominance clones that were considered as abiotic stress resistant mutants were transplanted to the field for further evaluation.

Milkweed butterfly resistance to plant toxins is linked to sequestration, not coping with a toxic diet.

Science.gov (United States)

Petschenka, Georg; Agrawal, Anurag A

2015-11-07

Insect resistance to plant toxins is widely assumed to have evolved in response to using defended plants as a dietary resource. We tested this hypothesis in the milkweed butterflies (Danaini) which have progressively evolved higher levels of resistance to cardenolide toxins based on amino acid substitutions of their cellular sodium-potassium pump (Na(+)/K(+)-ATPase). Using chemical, physiological and caterpillar growth assays on diverse milkweeds (Asclepias spp.) and isolated cardenolides, we show that resistant Na(+)/K(+)-ATPases are not necessary to cope with dietary cardenolides. By contrast, sequestration of cardenolides in the body (as a defence against predators) is associated with the three levels of Na(+)/K(+)-ATPase resistance. To estimate the potential physiological burden of cardenolide sequestration without Na(+)/K(+)-ATPase adaptations, we applied haemolymph of sequestering species on isolated Na(+)/K(+)-ATPase of sequestering and non-sequestering species. Haemolymph cardenolides dramatically impair non-adapted Na(+)/K(+)-ATPase, but had systematically reduced effects on Na(+)/K(+)-ATPase of sequestering species. Our data indicate that major adaptations to plant toxins may be evolutionarily linked to sequestration, and may not necessarily be a means to eat toxic plants. Na(+)/K(+)-ATPase adaptations thus were a potential mechanism through which predators spurred the coevolutionary arms race between plants and insects. © 2015 The Author(s).

Controversy Associated With the Common Component of Most Transgenic Plants – Kanamycin Resistance Marker Gene

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Srećko Jelenić

2003-01-01

Full Text Available Plant genetic engineering is a powerful tool for producing crops resistant to pests, diseases and abiotic stress or crops with improved nutritional value or better quality products. Currently over 70 genetically modified (GM crops have been approved for use in different countries. These cover a wide range of plant species with significant number of different modified traits. However, beside the technology used for their improvement, the common component of most GM crops is the neomycin phosphotransferase II gene (nptII, which confers resistance to the antibiotics kanamycin and neomycin. The nptII gene is present in GM crops as a marker gene to select transformed plant cells during the first steps of the transformation process. The use of antibiotic-resistance genes is subject to controversy and intense debate, because of the likelihood that clinical therapy could be compromised due to inactivation of the oral dose of the antibiotic from consumption of food derived from the transgenic plant, and because of the risk of gene transfer from plants to gut and soil microorganisms or to consumer’s cells. The present article discusses these possibilities in the light of current scientific knowledge.

Human Management of a Wild Plant Modulates the Evolutionary Dynamics of a Gene Determining Recessive Resistance to Virus Infection.

Science.gov (United States)

Poulicard, Nils; Pacios, Luis Fernández; Gallois, Jean-Luc; Piñero, Daniel; García-Arenal, Fernando

2016-08-01

This work analyses the genetic variation and evolutionary patterns of recessive resistance loci involved in matching-allele (MA) host-pathogen interactions, focusing on the pvr2 resistance gene to potyviruses of the wild pepper Capsicum annuum glabriusculum (chiltepin). Chiltepin grows in a variety of wild habitats in Mexico, and its cultivation in home gardens started about 25 years ago. Potyvirus infection of Capsicum plants requires the physical interaction of the viral VPg with the pvr2 product, the translation initiation factor eIF4E1. Mutations impairing this interaction result in resistance, according to the MA model. The diversity of pvr2/eIF4E1 in wild and cultivated chiltepin populations from six biogeographical provinces in Mexico was analysed in 109 full-length coding sequences from 97 plants. Eleven alleles were found, and their interaction with potyvirus VPg in yeast-two-hybrid assays, plus infection assays of plants, identified six resistance alleles. Mapping resistance mutations on a pvr2/eIF4E1 model structure showed that most were around the cap-binding pocket and strongly altered its surface electrostatic potential, suggesting resistance-associated costs due to functional constraints. The pvr2/eIF4E1 phylogeny established that susceptibility was ancestral and resistance was derived. The spatial structure of pvr2/eIF4E1 diversity differed from that of neutral markers, but no evidence of selection for resistance was found in wild populations. In contrast, the resistance alleles were much more frequent, and positive selection stronger, in cultivated chiltepin populations, where diversification of pvr2/eIF4E1 was higher. This analysis of the genetic variation of a recessive resistance gene involved in MA host-pathogen interactions in populations of a wild plant show that evolutionary patterns differ according to the plant habitat, wild or cultivated. It also demonstrates that human management of the plant population has profound effects on the

Human Management of a Wild Plant Modulates the Evolutionary Dynamics of a Gene Determining Recessive Resistance to Virus Infection.

Directory of Open Access Journals (Sweden)

Nils Poulicard

2016-08-01

Full Text Available This work analyses the genetic variation and evolutionary patterns of recessive resistance loci involved in matching-allele (MA host-pathogen interactions, focusing on the pvr2 resistance gene to potyviruses of the wild pepper Capsicum annuum glabriusculum (chiltepin. Chiltepin grows in a variety of wild habitats in Mexico, and its cultivation in home gardens started about 25 years ago. Potyvirus infection of Capsicum plants requires the physical interaction of the viral VPg with the pvr2 product, the translation initiation factor eIF4E1. Mutations impairing this interaction result in resistance, according to the MA model. The diversity of pvr2/eIF4E1 in wild and cultivated chiltepin populations from six biogeographical provinces in Mexico was analysed in 109 full-length coding sequences from 97 plants. Eleven alleles were found, and their interaction with potyvirus VPg in yeast-two-hybrid assays, plus infection assays of plants, identified six resistance alleles. Mapping resistance mutations on a pvr2/eIF4E1 model structure showed that most were around the cap-binding pocket and strongly altered its surface electrostatic potential, suggesting resistance-associated costs due to functional constraints. The pvr2/eIF4E1 phylogeny established that susceptibility was ancestral and resistance was derived. The spatial structure of pvr2/eIF4E1 diversity differed from that of neutral markers, but no evidence of selection for resistance was found in wild populations. In contrast, the resistance alleles were much more frequent, and positive selection stronger, in cultivated chiltepin populations, where diversification of pvr2/eIF4E1 was higher. This analysis of the genetic variation of a recessive resistance gene involved in MA host-pathogen interactions in populations of a wild plant show that evolutionary patterns differ according to the plant habitat, wild or cultivated. It also demonstrates that human management of the plant population has profound

In situ calibration of nuclear plant resistance thermometers using Johnson noise. Draft

International Nuclear Information System (INIS)

Blalock, T.V.; Roberts, M.J.; Shepard, R.L.

1984-01-01

Methods have been demonstrated in operating nuclear plants for the in situ calibration of resistance thermometers with agreement between measured noise temperatures and dc calibration temperatures well within these required by the plant. A comparison of the results of Johnson noise power testing results and uncertainties, the requirements for accuracy, and PRT calibration tolerances is shown. The methods use Johnson noise measurements and provide an absolute calibration independent of the prior dc calibration. The methods include techniques for characterization of the installed extension cables and the quantitative determination of induced EMI and its effect on the calibration. The techniques are applicable to ordinary 4-wire platinum resistance thermometers operating over their entire design temperature range and to extension cables of about 100 ft length. Careful attention needs to be paid to the choice or cables, location of terminal boxes, and grounding and shielding practices in the plant installation to achieve comparable results

Genomic analyses of metal resistance genes in three plant growth promoting bacteria of legume plants in Northwest mine tailings, China.

Science.gov (United States)

Xie, Pin; Hao, Xiuli; Herzberg, Martin; Luo, Yantao; Nies, Dietrich H; Wei, Gehong

2015-01-01

To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria (PGPB). It shows that: Mesorhizobium amorphae CCNWGS0123 contains metal transporters from P-type ATPase, CDF (Cation Diffusion Facilitator), HupE/UreJ and CHR (chromate ion transporter) family involved in copper, zinc, nickel as well as chromate resistance and homeostasis. Meanwhile, the putative CopA/CueO system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while ZntA transporter, assisted with putative CzcD, determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286. The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid (IAA) secretion, indicating a potential in-site phytoremediation usage in the mining tailing regions of China. Copyright © 2014. Published by Elsevier B.V.

Changes in Sprint and Jump Performances After Traditional, Plyometric, and Combined Resistance Training in Male Youth Pre- and Post-Peak Height Velocity.

Science.gov (United States)

Lloyd, Rhodri S; Radnor, John M; De Ste Croix, Mark B A; Cronin, John B; Oliver, Jon L

2016-05-01

The purpose of this study was to compare the effectiveness of 6-week training interventions using different modes of resistance (traditional strength, plyometric, and combined training) on sprinting and jumping performances in boys before and after peak height velocity (PHV). Eighty school-aged boys were categorized into 2 maturity groups (pre- or post-PHV) and then randomly assigned to (a) plyometric training, (b) traditional strength training, (c) combined training, or (d) a control group. Experimental groups participated in twice-weekly training programs for 6 weeks. Acceleration, maximal running velocity, squat jump height, and reactive strength index data were collected pre- and postintervention. All training groups made significant gains in measures of sprinting and jumping irrespective of the mode of resistance training and maturity. Plyometric training elicited the greatest gains across all performance variables in pre-PHV children, whereas combined training was the most effective in eliciting change in all performance variables for the post-PHV cohort. Statistical analysis indicated that plyometric training produced greater changes in squat jump and acceleration performances in the pre-PHV group compared with the post-PHV cohort. All other training responses between pre- and post-PHV cohorts were not significant and not clinically meaningful. The study indicates that plyometric training might be more effective in eliciting short-term gains in jumping and sprinting in boys who are pre-PHV, whereas those who are post-PHV may benefit from the additive stimulus of combined training.

Impact Assessment of Atmospheric Dust on Foliage Pigments and Pollution Resistances of Plants Grown Nearby Coal Based Thermal Power Plants.

Science.gov (United States)

Hariram, Manisha; Sahu, Ravi; Elumalai, Suresh Pandian

2018-01-01

Plant species grown in the vicinity of thermal power plants (TPP) are one of the immobile substrates to sink most of the pollutants emitted from their stacks. The continuous exposure of toxic pollutants to these plants may affect their resistances and essential biochemical's concentrations. In the present study, we estimated the impact of dust load generated by a TPPs to plant's dust retention capacity and pollution resistances (APTI and API). The observed ambient air quality index (AQI) showed that the surroundings of TPPs are in the severe air pollution category. Observed AQI was greater than 100 in the surrounding area of TPP. The mean dust load on plant foliage was significantly greater in the polluted site compared with the control site: 4.45 ± 1.96 versus 1.38 ± 0.41 mg cm -2 . Nearby, TPP highest and lowest dust load were founded in F. benghalensis (7.58 ± 0.74) and F. religiosa (2.25 ± 0.12 mg cm -2 ) respectively. Analysis revealed the strong negative correlation between dust load and essential pigments of foliage, such as chlorophyll content, carotenoids, pH of foliage extract, and relative water content. Conversely, strong positive correlation was observed with the ascorbic acid content of plant species. Correlation and percentage change analysis in ascorbic acid content for the polluted site against the control site showed the adverse impact on plants due to dust load. Based on their responses to dust pollution, A. scholaris, P. longifolia, and M. indica were observed as most suitable plant species. Estimation of DRC, chlorophyll a/b ratio, APTI and API revealed the A. scholaris, F. benghalensis, P. longifolia, and M. indica as the most suitable plant species for green belt formation. The high gradation was obtained in A. scholaris, F. benghalensis, P. longifolia, and M. indica for opted parameters and showed their most suitability for green belt formation. Salient features of the present study provide useful evidences to estimate the

Resistance selection on banana CV. Ambon Kuning Against Fusarium Wilt

International Nuclear Information System (INIS)

Sutarto, Ismiyarti; Meldia, Yeni; Jumjunidang

1998-01-01

This research was conducted in order to study the occurrence of mutation on irradiated plantlets and their resistance of plants of banana cv. Ambon Kuning against Fusarium wilt. Plantlets of banana cv. Ambon Kuning sized 5 cm were exposed to gamma rays at the doses 5 - 35 Gy intervals, then were subcultured for obtained M 1 V 5 plantlets. More over, the planlets were acclimatized and were planted in the field was already infected by Fasarium (f).culbense (FOC). The result indicated that irradiated plantlets of the doses 20 - 35 Gy were not able to survive up to 6 months after exposing to gamma rays. Abnormalities of M 1 V 5 plantlets originated from irradiated plantlets at the doses 10 and 15 Gy were shown on rossette plantlets with rigid and dark green leaves, and the formation of smooth mass morphologically shaped like calculus. The appearance of plant height and number of suckers of suckers of M 1 V 5 plants in the field was quite various. The number of survival plants after 8 moths planting was 8, 7, 15, and 28, respectively originated from untreated plants and irradiated plantlets at the doses 5, 10, and 15 Gy. After one year planting , only 2 plants were able to survive from irradiated plantlet at the dose 15 Gy. The plants could produce 27 plantlets obtained from culturing their shoot tips. Further study of these plantlets was needed in order create the stability of their resistance to FOC. (author)

Memory for target height is scaled to observer height.

Science.gov (United States)

Twedt, Elyssa; Crawford, L Elizabeth; Proffitt, Dennis R

2012-04-01

According to the embodied approach to visual perception, individuals scale the environment to their bodies. This approach highlights the central role of the body for immediate, situated action. The present experiments addressed whether body scaling--specifically, eye-height scaling--occurs in memory when action is not immediate. Participants viewed standard targets that were either the same height as, taller than, or shorter than themselves. Participants then viewed a comparison target and judged whether the comparison was taller or shorter than the standard target. Participants were most accurate when the standard target height matched their own heights, taking into account postural changes. Participants were biased to underestimate standard target height, in general, and to push standard target height away from their own heights. These results are consistent with the literature on eye-height scaling in visual perception and suggest that body scaling is not only a useful metric for perception and action, but is also preserved in memory.

ASSESSMENT OF IMPACT OF COHERENT LIGHT ON RESISTANCE OF PLANTS GROWING IN UNFAVOURABLE ENVIRONMENTAL CONDITIONS

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Małgorzata Śliwka

2014-04-01

Full Text Available The results of experiments on the effect of the coherent light emitted by lasers on plant material show that properly selected laser stimulation parameters, such as: wavelength, power, time and type of exposure, allow to obtain a greater growth of plant biomass, changes in the content of elements in the biomass and increasing plant resistance to unfavorable environmental conditions. The aim of this study was to determine the effect of laser stimulation on selected plant species (Iris pseudoacorus L., Lemna minor L. to increase their resistance to low temperatures and the ability to adapt to an environment polluted by mining activities (Phelum pratense L.. Plants from experimental groups (Iris pseudoacorus L., Phelum pratense L., Lemna minor L. were stimulated with coherent light with specific characteristics. To irradiate plants from experimental groups different algorithms of stimulation parameters, differentiating the method and time of exposure were used. Plants group without the stimulation, were the reference group. The article discusses the results of preliminary experiments carried out on a laboratory scale and pot experiments.

Effectors as Tools in Disease Resistance Breeding Against Biotrophic, Hemibiotrophic, and Necrotrophic Plant Pathogens

NARCIS (Netherlands)

Vleeshouwers, V.G.A.A.; Oliver, R.P.

2014-01-01

One of most important challenges in plant breeding is improving resistance to the plethora of pathogens that threaten our crops. The ever-growing world population, changing pathogen populations, and fungicide resistance issues have increased the urgency of this task. In addition to a vital inflow of

Childhood height, adult height, and the risk of prostate cancer

DEFF Research Database (Denmark)

Bjerregaard, Lise Geisler; Aarestrup, Julie; Gamborg, Michael

2016-01-01

PURPOSE: We previously showed that childhood height is positively associated with prostate cancer risk. It is, however, unknown whether childhood height exerts its effects independently of or through adult height. We investigated whether and to what extent childhood height has a direct effect...... on the risk of prostate cancer apart from adult height. METHODS: We included 5,871 men with height measured at ages 7 and 13 years in the Copenhagen School Health Records Register who also had adult (50-65 years) height measured in the Danish Diet, Cancer and Health study. Prostate cancer status was obtained...... through linkage to the Danish Cancer Registry. Direct and total effects of childhood height on prostate cancer risk were estimated from Cox regressions. RESULTS: From 1996 to 2012, 429 prostate cancers occurred. Child and adult heights were positively and significantly associated with prostate cancer risk...

Method for increasing the resistance of a plant or a part thereof to a pathogen, method for screening the resistance of a plant or part thereof to a pathogen, and use thereof

NARCIS (Netherlands)

Wit, de P.; Stergiopoulos, I.; Kema, G.H.J.

2011-01-01

(EN)The present invention relates to the field of plant biotechnology. More in particular, the present invention relates to methods for increasing the resistance of a plant or part thereof that is susceptible to infection with a pathogen comprising an ortholog of the Avr4 protein of Cladosporium

Understanding rice plant resistance to the Brown Planthopper (Nilaparvata lugens): a proteomic approach.

Science.gov (United States)

Wei, Zhe; Hu, Wei; Lin, Qishan; Cheng, Xiaoyan; Tong, Mengjie; Zhu, Lili; Chen, Rongzhi; He, Guangcun

2009-05-01

Engineering and breeding resistant plant varieties are the most effective and environmentally friendly ways to control agricultural pests and improve crop performance. However, the mechanism of plant resistance to pests is poorly understood. Here we used a quantitative mass-spectrometry-based proteomic approach for comparative analysis of expression profiles of proteins in rice leaf sheaths in responses to infestation by the brown planthopper (Nilaparvata lugens Stål, BPH), which is a serious rice crop pest. Proteins involved in multiple pathways showed significant changes in expression in response to BPH feeding, including jasmonic acid synthesis proteins, oxidative stress response proteins, beta-glucanases, protein; kinases, clathrin protein, glycine cleavage system protein, photosynthesis proteins and aquaporins. The corresponding genes of eight important proteins were further analyzed by quantitative RT-PCR. Proteomic and transcript responses that were related to wounding, oxidative and pathogen stress overlapped considerably between BPH-resistant (carrying the resistance gene BPH15) and susceptible rice lines. In contrast, proteins and genes related to callose metabolism remained unchanged and glycine cleavage system protein was up-regulated in the BPH-resistant lines, indicating that they have an efficient and specific defense mechanism. Our results provide new information about the interaction between rice and the BPH.

Growth of Verticillium longisporum in Xylem Sap of Brassica napus is Independent from Cultivar Resistance but Promoted by Plant Aging.

Science.gov (United States)

Lopisso, Daniel Teshome; Knüfer, Jessica; Koopmann, Birger; von Tiedemann, Andreas

2017-09-01

As Verticillium stem striping of oilseed rape (OSR), a vascular disease caused by Verticillium longisporum, is extending into new geographic regions and no control with fungicides exists, the demand for understanding mechanisms of quantitative resistance increases. Because V. longisporum is strictly limited to the xylem and resistance is expressed in the systemic stage post root invasion, we investigated a potential antifungal role of soluble constituents and nutritional conditions in xylem sap as determinants of cultivar resistance of OSR to V. longisporum. Assessment of biometric and molecular genetic parameters applied to describe V. longisporum resistance (net area under disease progress curve, stunting, stem thickness, plant biomass, and V. longisporum DNA content) showed consistent susceptibility of cultivar 'Falcon' in contrast to two resistant genotypes, 'SEM' and 'Aviso'. Spectrophotometric analysis revealed a consistently stronger in vitro growth of V. longisporum in xylem sap extracted from OSR compared with the water control. Further comparisons of fungal growth in xylem sap of different cultivars revealed the absence of constitutive or V. longisporum induced antifungal activity in the xylem sap of resistant versus susceptible genotypes. The similar growth of V. longisporum in xylem sap, irrespective of cultivar, infection with V. longisporum and xylem sap filtration, was correlated with about equal amounts of total soluble proteins in xylem sap from these treatments. Interestingly, compared with younger plants, xylem sap from older plants induced significantly stronger fungal growth. Growth enhancement of V. longisporum in xylem sap of aging plants was reflected by increased contents of carbohydrates, which was consistent in mock or V. longisporum-infected plants and independent from cultivar resistance. The improved nutritional conditions in the xylem of more mature plants may explain the late appearance of disease symptoms, which are observed only in

Above- and Belowground Trophic Interactions on Creeping Thistle (Cirsium arvense) in High- and Low-Diversity Plant Communities: Potential for Biotic Resistance?

NARCIS (Netherlands)

Bezemer, T.M.; Graça, O.; Rousseau, P.; Van der Putten, W.H.

2004-01-01

The capacity of local communities to control introduced plants is called biotic resistance. Biotic resistance has been almost exclusively tested for plant competition and aboveground herbivores and pathogens, while neglecting root herbivores and soil pathogens. Here, we present biotic resistance by

Biological Effects of Potato Plants Transformation with Glucose Oxidase Gene and their Resistance to Hyperthermia

Directory of Open Access Journals (Sweden)

O.I. Grabelnych

2017-02-01

Full Text Available It is known that regulation of plant tolerance to adverse environmental factors is connected with short term increase of the concentration of endogenous reactive oxygen species (ROS, which are signalling molecules for the induction of protective mechanisms. Introduction and expression of heterologous gox gene, which encodes glucose oxidase enzyme in plant genome, induce constantly higher content of hydrogen peroxide in plant tissues. It is not known how the introduction of native or modified gox gene affects the plant resistance to high-temperature stress, one of the most commonly used model for the study of stress response and thermal tolerance. In this study, we investigated biological effects of transformation and evaluated the resistance to temperature stress of potato plants with altered levels of glucose oxidase expression. Transformation of potato plants by gox gene led to the more early coming out from tuber dormancy of transformed plants and slower growth rate. Transformants containing the glucose oxidase gene were more sensitive to lethal thermal shock (50 °C, 90 min than the transformant with the empty vector (pBI or untransformed plants (CK. Pre-heating of plants at 37 °C significantly weakened the damaging effect of lethal thermal shock. This attenuation was more significant in the non-transformed plants.

The Impact of "Coat Protein-Mediated Virus Resistance" in Applied Plant Pathology and Basic Research.

Science.gov (United States)

Lindbo, John A; Falk, Bryce W

2017-06-01

Worldwide, plant viruses cause serious reductions in marketable crop yield and in some cases even plant death. In most cases, the most effective way to control virus diseases is through genetically controlled resistance. However, developing virus-resistant (VR) crops through traditional breeding can take many years, and in some cases is not even possible. Because of this, the demonstration of the first VR transgenic plants in 1985 generated much attention. This seminal report served as an inflection point for research in both basic and applied plant pathology, the results of which have dramatically changed both basic research and in a few cases, commercial crop production. The typical review article on this topic has focused on only basic or only applied research results stemming from this seminal discovery. This can make it difficult for the reader to appreciate the full impact of research on transgenic virus resistance, and the contributions from fundamental research that led to translational applications of this technology. In this review, we take a global view of this topic highlighting the significant changes to both basic and applied plant pathology research and commercial food production that have accumulated in the last 30 plus years. We present these milestones in the historical context of some of the scientific, economic, and environmental drivers for developing specific VR crops. The intent of this review is to provide a single document that adequately records the significant accomplishments of researchers in both basic and applied plant pathology research on this topic and how they relate to each other. We hope this review therefore serves as both an instructional tool for students new to the topic, as well as a source of conversation and discussion for how the technology of engineered virus resistance could be applied in the future.

Electroantennogram Responses to Plant Volatiles Associated with Fenvalerate Resistance in the Diamondback Moth, Plutella xylostella (Lepidoptera: Plutellidae).

Science.gov (United States)

Houjun, Tian; Lin, Shuo; Chen, Yong; Chen, Yixin; Zhao, Jianwei; Gu, Xiaojun; Wei, Hui

2018-05-28

The diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Plutellidae), is the main destructive insect pest of brassica vegetables around the world, and has developed resistance to numerous insecticides. Although host plant volatiles are important in pest control, the mechanism of low-level insecticide resistance in P. xylostella due to plant volatiles has not been examined. Here, electroantennograms (EAGs) were used to compare the responses of adult male and female DBMs of a susceptible strain (S-strain) and a derived resistant strain, Fen-R-strain (6.52-fold more resistant than the S-strain), to different concentrations of nine plant volatiles. We found significantly different relative EAG responses between S-strain and Fen-R-strain males to different concentrations of methyl jasmonate, methyl salicylate, and octanal. The relative EAG responses of S-strain and Fen-R-strain females to different concentrations of β-myrcene, methyl jasmonate, methyl salicylate, and allyl isothiocyanate were significantly different. Fen-R-strain females showed lower EAG responses to most of the tested plant volatiles (at concentrations of 1:10) than males, except for allyl isothiocyanate. A larger difference in relative EAG response to α-farnesene and β-myrcene was found between S-strain and Fen-R-strain females than between males of the two strains. A larger difference in relative EAG response to octanal, nonanal, and octan-1-ol was found between S-strain and Fen-R-strain males than between females of the two strains. These results illustrate the relationship between the function of plant volatiles and resistance in an insect pest species, and provide a scientific basis for resistance evolutionary theory in pest management research.

Pest and disease resistance enhanced by heterologous suppression of a Nicotiana plumbaginifolia cytochrome P450 gene CYP72A2.

Science.gov (United States)

Smigocki, Ann C; Wilson, Dennis

2004-12-01

The functional role of the Nicotiana plumbaginifolia cytochrome P450 gene CYP72A2 was investigated in transgenic plants. N. tabacum plants transformed with a sense or antisense CYP72A2 construct exhibited diminished heights, branched stems, smaller leaves and deformed flowers. Western blot analysis revealed reduced levels of a 58 kDa protein corresponding to CYP72A2, suggesting that the CYP72A2 homolog was suppressed in the sense and antisense plants. Transgenic plants had increased resistance to Manduca sexta larvae that consumed about 35 to 90 less of transgenic versus control leaves. A virulent strain of Pseudomonas syringae pv. tabaci induced a disease-limiting response followed by a delayed and decreased development of disease symptoms in the transgenics. CYP72A2 gene mediated resistance suggests that the plant-pest or -pathogen interactions may have been modified by changes in bioactive metabolite pools.

A Quantitative Method to Screen Common Bean Plants for Resistance to Bean common mosaic necrosis virus.

Science.gov (United States)

Strausbaugh, C A; Myers, J R; Forster, R L; McClean, P E

2003-11-01

ABSTRACT A quantitative method to screen common bean (Phaseolus vulgaris) plants for resistance to Bean common mosaic necrosis virus (BCMNV) is described. Four parameters were assessed in developing the quantitative method: symptoms associated with systemic virus movement, plant vigor, virus titer, and plant dry weight. Based on these parameters, two rating systems (V and VV rating) were established. Plants from 21 recombinant inbred lines (RILs) from a Sierra (susceptible) x Olathe (partially resistant) cross inoculated with the BCMNV-NL-3 K strain were used to evaluate this quantitative approach. In all, 11 RILs exhibited very susceptible reactions and 10 RILs expressed partially resistant reactions, thus fitting a 1:1 susceptible/partially resistant ratio (chi(2) = 0.048, P = 0.827) and suggesting that the response is mediated by a single gene. Using the classical qualitative approach based only on symptom expression, the RILs were difficult to separate into phenotypic groups because of a continuum of responses. By plotting mean percent reduction in either V (based on visual symptoms) or VV (based on visual symptoms and vigor) rating versus enzyme-linked immunosorbent assay (ELISA) absorbance values, RILs could be separated clearly into different phenotypic groups. The utility of this quantitative approach also was evaluated on plants from 12 cultivars or pure lines inoculated with one of three strains of BCMNV. Using the mean VV rating and ELISA absorbance values, significant differences were established not only in cultivar and pure line comparisons but also in virus strain comparisons. This quantitative system should be particularly useful for the evaluation of the independent action of bc genes, the discovery of new genes associated with partial resistance, and assessing virulence of virus strains.

Durable broad-spectrum powdery mildew resistance in pea er1 plants is conferred by natural loss-of-function mutations in PsMLO1

NARCIS (Netherlands)

Humphry, M.; Reinstädler, A.; Ivanov, S.; Bisseling, T.; Panstruga, R.

2011-01-01

Loss-of-function alleles of plant-specific MLO (Mildew Resistance Locus O) genes confer broad-spectrum powdery mildew resistance in monocot (barley) and dicot (Arabidopsis thaliana, tomato) plants. Recessively inherited powdery mildew resistance in pea (Pisum sativum) er1 plants is, in many aspects,

Physiological Responses to N-NO3 and N-NH4 of Triazine Resistant and Susceptible Plants of Horseweed (Erigeron canadensis L.

Directory of Open Access Journals (Sweden)

Ryszard Stanek

2013-12-01

Full Text Available Triazine resistant and susceptible biotypes of horseweed (Erigeron canadensis L. were grown under controlled conditions in nutrient solution with NH4 or NO3 ions as nitrogen source. Indicators such as: dry matter, CO2 assimilation, chloroplasts activity, dark respiration and the content of K, Ca, Mg in the above ground parts displayed lower levels when plants were fed with NH4 than with NO ions. Reduction of these indicators was stronger for the triazine susceptible plants which grew better than their resistant counterparts when fed with N-NO3. The triazine resistant plants grown with N-NH4 contained more protein-N and K than the susceptible ones. Chloroplasts of the resistant plants were also less sensitive to NH4CL treatment. It is concluded that the resistant plants appear to be more tolerant to NH4 ions as compared with their susceptible counterparts. For this reason application of ammonium forms of nitrogen fertilization in horticultural practice could favour spreading of triazine resistant horseweed.

Fall from heights: does height really matter?

Science.gov (United States)

Alizo, G; Sciarretta, J D; Gibson, S; Muertos, K; Romano, A; Davis, J; Pepe, A

2018-06-01

Fall from heights is high energy injuries and constitutes a fraction of all fall-related trauma evaluations while bearing an increase in morbidity and mortality. We hypothesize that despite advancements in trauma care, the overall survivability has not improved in this subset of trauma patients. All adult trauma patients treated after sustaining a fall from heights during a 40-month period were retrospectively reviewed. Admission demographics, clinical data, fall height (ft), injury patterns, ISS, GCS, length of stay, and mortality were reviewed. 116 patients sustained a fall from heights, 90.4% accidental. A mean age of 37± 14.7 years, 86% male, and a fall height of 19 ± 10 ft were encountered. Admission GCS was 13 ± 2 with ISS 10 ± 11. Overall LOS was 6.6 ± 14.9 days and an ICU LOS of 2.8 ± 8.9 days. Falls ≥ 25 ft.(16%) had lower GCS 10.4 ± 5.8, increased ISS 22.6 ± 13.8, a fall height 37.9 ± 13.1 ft and associated increased mortality (p < 0.001). Mortality was 5.2%, a mean distance fallen of 39 ± 22 ft. and an ISS of 31.5 ±16.5. Brain injury was the leading cause of death, 50% with open skull fractures. Level of height fallen is a good predictor of overall outcome and survival. Despite advances in trauma care, death rates remain unchanged. Safety awareness and injury prevention programs are needed to reduce the risk of high-level falls.

Above- and Belowground Trophic Interactions on Creeping Thistle (Cirsium arvense) in High- and Low-Diversity Plant Communities: Potential for Biotic Resistance?

NARCIS (Netherlands)

Bezemer, T.M.; Graça, O.; Rousseau, P.; Putten, van der W.H.

2004-01-01

The capacity of local communities to control introduced plants is called biotic resistance. Biotic resistance has been almost exclusively tested for plant competition and above-ground herbivores and pathogens, while neglecting root herbivores and soil pathogens. Here, we present biotic resistance by

Trichoderma harzianum T-22 induces systemic resistance in tomato infected by Cucumber mosaic virus

Directory of Open Access Journals (Sweden)

Antonella Vitti

2016-10-01

Full Text Available Understanding the induction of plant defenses against viruses using biocontrol agents is essential for developing new strategies against these pathogens, given the ineffectiveness of chemical treatments. The ability of Trichoderma harzianum, strain T-22 (T22 to control Cucumber mosaic virus (CMV in Solanum lycopersicum var. cerasiforme plants and the changes in the physiology of tomato treated/infected with T22/CMV were examined. Plant growth-promoting effects, photosynthetic performance, reactive oxygen species (ROS scavenging enzymes, and phytohormones were investigated. T22 improved tomato growth in terms of plant height and improved photosynthesis, total chlorophyll content and plant gas exchange. In contrast, CMV induced a negative effect on dry matter accumulation and inhibited the photosynthetic capacity. The analysis of plant hormones demonstrated that treating with T22 before or simultaneously to CMV infection, led to a systemic resistance by jasmonic acid/ethylene and salicylic acid signaling pathways. Conversely, systemic resistance was abscissic acid-dependent when T22 treatment was administered after the CMV infection. In conclusion, the data reported here indicate that the T22-based strategy may be the most effective measure against CMV.

Aldo-keto reductase enzymes detoxify glyphosate and improve herbicide resistance in plants.

Science.gov (United States)

Vemanna, Ramu S; Vennapusa, Amaranatha Reddy; Easwaran, Murugesh; Chandrashekar, Babitha K; Rao, Hanumantha; Ghanti, Kirankumar; Sudhakar, Chinta; Mysore, Kirankumar S; Makarla, Udayakumar

2017-07-01

In recent years, concerns about the use of glyphosate-resistant crops have increased because of glyphosate residual levels in plants and development of herbicide-resistant weeds. In spite of identifying glyphosate-detoxifying genes from microorganisms, the plant mechanism to detoxify glyphosate has not been studied. We characterized an aldo-keto reductase gene from Pseudomonas (PsAKR1) and rice (OsAKR1) and showed, by docking studies, both PsAKR1 and OsAKR1 can efficiently bind to glyphosate. Silencing AKR1 homologues in rice and Nicotiana benthamiana or mutation of AKR1 in yeast and Arabidopsis showed increased sensitivity to glyphosate. External application of AKR proteins rescued glyphosate-mediated cucumber seedling growth inhibition. Regeneration of tobacco transgenic lines expressing PsAKR1 or OsAKRI on glyphosate suggests that AKR can be used as selectable marker to develop transgenic crops. PsAKR1- or OsAKRI-expressing tobacco and rice transgenic plants showed improved tolerance to glyphosate with reduced accumulation of shikimic acid without affecting the normal photosynthetic rates. These results suggested that AKR1 when overexpressed detoxifies glyphosate in planta. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Non-host Plant Resistance against Phytophthora capsici Is Mediated in Part by Members of the I2 R Gene Family in Nicotiana spp.

Science.gov (United States)

Vega-Arreguín, Julio C; Shimada-Beltrán, Harumi; Sevillano-Serrano, Jacobo; Moffett, Peter

2017-01-01

The identification of host genes associated with resistance to Phytophthora capsici is crucial to developing strategies of control against this oomycete pathogen. Since there are few sources of resistance to P. capsici in crop plants, non-host plants represent a promising source of resistance genes as well as excellent models to study P. capsici - plant interactions. We have previously shown that non-host resistance to P. capsici in Nicotiana spp. is mediated by the recognition of a specific P. capsici effector protein, PcAvr3a1 in a manner that suggests the involvement of a cognate disease resistance (R) genes. Here, we have used virus-induced gene silencing (VIGS) and transgenic tobacco plants expressing dsRNA in Nicotiana spp. to identify candidate R genes that mediate non-host resistance to P. capsici . Silencing of members of the I2 multigene family in the partially resistant plant N. edwardsonii and in the resistant N. tabacum resulted in compromised resistance to P. capsici . VIGS of two other components required for R gene-mediated resistance, EDS1 and SGT1 , also enhanced susceptibility to P. capsici in N. edwardsonii , as well as in the susceptible plants N. benthamiana and N. clevelandii . The silencing of I2 family members in N. tabacum also compromised the recognition of PcAvr3a1. These results indicate that in this case, non-host resistance is mediated by the same components normally associated with race-specific resistance.

Effects of heavy metals on plants and resistance mechanisms. A state-of-the-art report with special reference to literature published in Chinese journals.

Science.gov (United States)

Cheng, Shuiping

2003-01-01

As one of the consequences of heavy metal pollution in soil, water and air, plants are contaminated by heavy metals in some parts of China. To understand the effects of heavy metals upon plants and the resistance mechanisms, would make it possible to use plants for cleaning and remediating heavy metal-polluted sites. The research results on the effects of heavy metals on plants and resistant mechanisms are compiled from Chinese publications from scientific journals and university journals, mostly published during the last decade. Effects of heavy metals on plants result in growth inhibition, structure damage, a decline of physiological and biochemical activities as well as of the function of plants. The effects and bioavailability of heavy metals depend on many factors, such as environmental conditions, pH, species of element, organic substances of the media and fertilization, plant species. But, there are also studies on plant resistance mechanisms to protect plants against the toxic effects of heavy metals such as combining heavy metals by proteins and expressing of detoxifying enzyme and nucleic acid, these mechanisms are integrated to protect the plants against injury by heavy metals. There are two aspects on the interaction of plants and heavy metals. On one hand, heavy metals show negative effects on plants. On the other hand, plants have their own resistance mechanisms against toxic effects and for detoxifying heavy metal pollution. To study the effects of heavy metals on plants and mechanisms of resistance, one must select crop cultivars and/or plants for removing heavy metals from soil and water. More highly resistant plants can be selected especially for a remediation of the pollution site. The molecular mechanisms of resistance of plants to heavy metals should be studied further to develop the actual resistance of these plants to heavy metals. Understanding the bioavailability of heavy metals is advantageous for plant cultivation and phytoremediation

Induced resistance: an enhancement of basal resistance?

NARCIS (Netherlands)

Vos, M. de; Robben, C.; Pelt, J.A. van; Loon, L.C. van; Pieterse, C.M.J.

2002-01-01

Upon primary pathogen attack, plants activate resistance mechanisms at the site of infection. Besides this so-called basal resistance, plants have also the ability to enhance their defensive capacity against future pathogen attack. There are at least two types of biologically induced resistance.

Potential for biotic resistance from herbivores to tropical and subtropical plant invasions in aquatic ecosystems

NARCIS (Netherlands)

Petruzella, A.; Grutters, B.M.C.; Thomaz, S.M.; Bakker, E.S.

2017-01-01

Invasions of tropical and subtropical aquatic plants threaten biodiversity and cause ecological and economic impacts worldwide. An urgent question is whether native herbivores are able to inhibit the spread of these alien species thus providing biotic resistance. The potential for biotic resistance

Height suppression of tomato plug seedlings by an environment ...

African Journals Online (AJOL)

Experiments were conducted to investigate appropriate concentrations of plant growth retardants (PGRs) and duration of seed soaking in order to suppress hypocotyl length and plug seedling height of 2 tomato cultivars ( Lycopersicum esculentum Mill. cv. Seogeon and Seokwang). Daminozide (B-9), uniconazole ...

Results of two years of water training on jump height in postmenopausal women with moderate hip risk fracture

Directory of Open Access Journals (Sweden)

María Carrasco Poyatos

2010-01-01

Full Text Available The aim of the present study was to investigate the effect of a water-based calisthenics and resistance program on jump height in postmenopausal women with moderate hip risk fracture. 39 women were divided into three groups: swimming group (GN; n = 17, calisthenics and resistance group (GIR; n = 14, and control group (GC; n = 8. Body composition test included body mass index (IMC and waist to hip ratio (ICC. Jump height was assessed by a countermovement jump (CMJ. GN showed a significant (p<0.05 decrease in ICC (5.81%. GIR showed a significant decrease in IMC (3.65% and a significant increase in CMJ (15.5%. Two years of water-based calisthenics and resistance training can offer significant benefits in jump height in postmenopausal women with moderate hip risk fracture. Both exercise programs can also improve body composition.

Effect of Chlorocholine Chloride (CCC on the Plants’ Height and Inulin Content in Jerusalem Artichoke (Helianthus tuberosus L.

Directory of Open Access Journals (Sweden)

Mikołaj Wawrzyniak

2016-11-01

Full Text Available Jerusalem artichoke (Helianthus tuberosus L. is herbaceous perennial plant rich in inulin and useful source of biomass. Due to its low agricultural requirements and high adaptability, it can provide very high biomass yields even on low quality sites. The plant is used in food industry, bio-fuel production, forage, pharmacy and nutrition. Its tubers accumulate approx. 10-20% of inulin in fresh weight. Currently, the use of the Helianthius tuberosus L. as a potential dietary strategy in patients affected by type 2 Diabetes is challenge. Moreover, deep understanding of the relationship between diet and composition of gut microbiota can bring the new insight in the treatment of inflammatory dependent diseases. The aim of this study was to examine an effect of plant growth retardant Chlorocholine Chloride (CCC on the plants’ height of H. tuberosus and inulin content in the tubers. We examined in the field a procedure for its shoots reduction. Material for the experiment were bought in a Polish commercial company and 528 tubers were planted in field in the middle of April 2014. Then, half of them were sprayed with 0.75% retardant of CCC . Furthermore, every week for 12 following weeks, the plants’ heights were measured. After the vegetation was over, 6 tubers for each treatment were dug out and chemically analyzed for inulin content using High Pressure Size Exclusion Chromatography. After first week of CCC use, 16% decrease of the heights plants was observed. Height of plants sprayed with CCC were significantly different comparing to Control. Weekly growth was significantly  slower in plants sprayed with CCC on first three weeks after applying retardant. Differences in plants height sustain to the end of measurements. Used retardant and its concentration did not affect the inulin content of the tubers.

Rhamnolipids production by multi-metal-resistant and plant-growth-promoting rhizobacteria.

Science.gov (United States)

Singh, Anil Kumar; Cameotra, Swaranjit Singh

2013-07-01

The biosurfactant-producing Pseudomonas aeruginosa A11, with plant-growth-promoting (PGP) and multi-metal-resistant (MMR) features was isolated from the rhizosphere of a wild plant Parthenium hysterophorus. The strain A11 was able to utilize glycerol as a carbon source and produce 4,436.9 mg/L of biosurfactant after 120 h of incubation. The biosurfactants was characterized as rhamnolipids (RLs) by thin layer chromatography, Fourier transform infrared spectroscopy, nuclear magnetic resonance, and liquid chromatography-mass spectrometry analysis. Eight different RLs congeners were detected with RhaRhaC₁₀C₁₀ being most abundant. The purified rhamnolipid, dirhamnolipid, and monorhamnolipid reduced the surface tension of water to 29, 36, and 42 mN/m with critical micelle concentration of 83, 125, and 150 mg/L, respectively. The strain A11 demonstrated resistance against all the metals detected in rhizosphere except Hg and Ni. The strain A11 also possessed plant-growth-promoting features like siderophores, hydrogen cyanide, catalase, ammonia production, and phosphate solubilization. The dirhamnolipids formed crystals upon incubation at 4 °C, thus making separation of dirhamnolipids easy. Biosurfactant-producing ability along with MMR and PGP traits of the strain A11 makes it a potential candidate for application in the bacterial assisted enhancement of phytoremediation of heavy-metal-contaminated sites.

Identification of differentially expressed genes in brown planthopper Nilaparvata lugens (Hemiptera: Delphacidae) responding to host plant resistance.

Science.gov (United States)

Yang, Zhifan; Zhang, Futie; Zhu, Lili; He, Guangcun

2006-02-01

The brown planthopper Nilaparvata lugens Stål is one of the major insect pests of rice Oryza sativa L. The host resistance exhibits profound effects on growth, development and propagation of N. lugens. To investigate the molecular response of N. lugens to host resistance, a cDNA-amplified fragment length polymorphism (cDNA-AFLP) technique was employed to identify the differentially expressed genes in the nymphs feeding on three rice varieties. Of the 2,800 cDNA bands analysed, 54 were up-regulated and seven down-regulated qualitatively in N. lugens when the ingestion sources were changed from susceptible rice plants to resistant ones. Sequence analysis of the differential transcript-derived fragments showed that the genes involved in signalling, stress response, gene expression regulation, detoxification and metabolism were regulated by host resistance. Four of the transcript-derived fragments corresponding to genes encoding for a putative B subunit of phosphatase PP2A, a nemo kinase, a cytochrome P450 monooxygenase and a prolyl endopeptidase were further characterized in detail. Northern blot analysis confirmed that the expression of the four genes was enhanced in N. lugens feeding on resistant rice plants. The roles of these genes in the defensive response of N. lugens to host plant resistance were discussed.

[The influence of colonizing methylobacteria on morphogenesis and resistance of sugar beet and white cabbage plants to Erwinia carotovora].

Science.gov (United States)

Pigoleva, S V; Zakharchenko, N S; Pigolev, A V; Trotsenko, Iu A; Bur'ianov, Ia I

2009-01-01

The influence of colonization of sugar beet (Beta vulgaris var. saccharifera (Alef) Krass) and white cabbage (Brassica oleracea var. capitata L.) plants by methylotrophic bacteria Methylovorus mays on the growth, rooting, and plant resistance to phytopathogen bacteria Erwinia carotovora was investigated. The colonization by methylobacteria led to their steady association with the plants which had increased growth speed, root formation and photosynthetic activity. The colonized plants had increased resistance to Erwinia carotovora phytopathogen and were better adapted to greenhouse conditions. The obtained results showed the perspectives for the practical implementation of methylobacteria in the ecologically clean microbiology substances used as the plant growth stimulators and for the plant protection from pathogens.

Brassinosteroid action in flowering plants: a Darwinian perspective.

Science.gov (United States)

Kutschera, Ulrich; Wang, Zhi-Yong

2012-06-01

The year 2012 marks the 150th anniversary of the publication of Charles Darwin's first botanical book, on the fertilization of orchids (1862), wherein he described pollen grains and outlined his evolutionary principles with respect to plant research. Five decades later, the growth-promoting effect of extracts of Orchid pollen on coleoptile elongation was documented. These studies led to the discovery of a new class of phytohormones, the brassinosteroids (BRs) that were isolated from rapeseed (Brassica napus) pollen. These growth-promoting steroids, which regulate height, fertility, and seed-filling in crop plants such as rice (Oryza sativa), also induce stress- and disease resistance in green algae and angiosperms. The origin and current status of BR-research is described here, with reference to BR-action and -signal transduction, and it is shown that modern high-yield rice varieties with erect leaves are deficient in endogenous BRs. Since brassinosteroids induce pathogen resistance in rice plants and hence can suppress rice blast- and bacterial blight-diseases, genetic manipulation of BR-biosynthesis or -perception may be a means to increase crop production. Basic research on BR activity in plants, such as Arabidopsis and rice, has the potential to increase crop yields further as part of a 21th century 'green biotech-revolution' that can be traced back to Darwin's classical breeding experiments. It is concluded that 'Nothing in brassinosteroid research makes sense except in the light of Darwinian evolution' and the value of basic science is highlighted, with reference to the genetic engineering of better food crops that may become resistant to a variety of plant diseases.

Radiation resistant polymers and coatings for nuclear fuel reprocessing plants

International Nuclear Information System (INIS)

Kamachi Mudali, U.; Mallika, C.; Lawrence, Falix

2014-01-01

Polymer based materials are extensively used in the nuclear industry for the reprocessing of spent fuels in highly radioactive and corrosive environment. Hence, these polymer materials are susceptible to damage by ionizing radiation, resulting in the degradation in properties. Polymers containing aromatic molecules generally possess higher resistance to radiation degradation than the aliphatic polymers. For improving the radiation resistance of polymers various methods are reported in the literature. Among the aromatic polymers, polyetheretherketone (PEEK) has the radiation tolerance up to 10 Mega Grey (MGy). To explore the possibility of enhancing the radiation resistance of PEEK, a study was initiated to develop PEEK - ceramic composites and evaluate the effect of radiation on the properties of the composites. PEEK and PEEK - alumina (micron size) composites were irradiated in a gamma chamber using 60 Co source and the degradation in mechanical, structural, electrical and thermal properties, gel fraction, coefficient of friction and morphology were investigated. The degradation in the mechanical properties owing to radiation could be reduced by adding alumina filler to PEEK. Nano alumina filler was observed to be more effective in suppressing the damage caused by radiation on the polymer, when compared to micron alumina filler. For the protection of aluminium components in the manipulators and the rotors and stators of the motors of the centrifugal extractors employed in the plant from the attack by nitric acid vapour, PEEK coating based on liquid dispersion was developed, which has resistance to radiation, chemicals and wear. The effect of radiation and chemical vapour on the properties of the PEEK coating was estimated. The performance of the coating in the plant was evaluated and the coating was found to give adequate protection to the motors of centrifugal extractors against corrosion. (author)

Mapping and characterization of the new adult plant leaf rust resistance gene Lr77 derived from Santa Fe winter wheat.

Science.gov (United States)

Kolmer, James A; Su, Zhenqi; Bernardo, Amy; Bai, Guihua; Chao, Shiaoman

2018-04-25

A new gene for adult plant leaf rust resistance in wheat was mapped to chromosome 3BL. This gene was designated as Lr77. 'Santa Fe' is a hard red winter cultivar that has had long-lasting resistance to the leaf rust fungus, Puccinia triticina. The objective of this study was to determine the chromosome location of the adult plant leaf rust resistance in Santa Fe wheat. A partial backcross line of 'Thatcher' (Tc) wheat with adult plant leaf rust resistance derived from Santa Fe was crossed with Thatcher to develop a Thatcher//Tc*2/Santa Fe F 6 recombinant inbred line (RIL) population. The RIL population and parental lines were evaluated for segregation of leaf rust resistance in three field plot tests and in an adult plant greenhouse test. A genetic map of the RIL population was constructed using 90,000 single-nucleotide polymorphism (SNP) markers with the Illumina Infinium iSelect 90K wheat bead array. A significant quantitative trait locus for reduction of leaf rust severity in all four tests was found on chromosome 3BL that segregated as a single adult plant resistance gene. The RILs with the allele from the resistant parent for SNP marker IWB10344 had lower leaf rust severity and a moderately resistant to moderately susceptible response compared to the susceptible RILs and Thatcher. The gene derived from Santa Fe on chromosome 3BL was designated as Lr77. Kompetitive allele-specific polymerase chain reaction assay markers linked to Lr77 on 3BL should be useful for selection of wheat germplasm with this gene.

Investigations on the mechanism of oxygen-dependent plant processes: ethylene biosynthesis and cyanide-resistant respiration

International Nuclear Information System (INIS)

Stegink, S.J.

1985-01-01

Two oxygen-dependent plant processes were investigated. A cell-free preparation from pea (Pisum sativum L., cv. Alaska) was used to study ethylene biosynthesis from 1-aminocyclopropane-1-carboxylic acid. Mitochondrial cyanide-resistant respiration was investigated in studies with 14 C-butyl gallate and other respiratory effectors. Ethylene biosynthesis was not due to a specific enzyme, or oxygen radicals. Rather, hydrogen peroxide, generated at low levels, coupled with endogenous manganese produced ethylene. 14 C-butyl gallate bound specifically to mitochondria from cyanide-sensitive and -resistant higher plants and Neurospora crassa mitochondria. The amount of gallate bound was similar for all higher plant mitochondria. Rat liver mitochondria bound very little 14 C-butyl gallate. Plant mitochondria in which cyanide-resistance was induced bound as much 14 C-butyl gallate as before induction. However mitochondria from recently harvested white potato tubers did not bind the gallate. The observations suggest that an engaging factor couples with a gallate binding site in the mitochondrial membrane. With skunk cabbage spadix mitochondria the I 5 0 for antimycin A inhibition of oxygen uptake was decreased by salicylhydroxamic acid pretreatment; this was also true for reverse order additions. No shift was observed with mung bean hypocotyl or Jerusalem artichoke tuber mitochondria

Adult Plant Leaf Rust Resistance Derived from Toropi Wheat is Conditioned by Lr78 and Three Minor QTL.

Science.gov (United States)

Kolmer, J A; Bernardo, A; Bai, G; Hayden, M J; Chao, S

2018-02-01

Leaf rust caused by Puccinia triticina is an important disease of wheat in many regions worldwide. Durable or long-lasting leaf rust resistance has been difficult to achieve because populations of P. triticina are highly variable for virulence to race-specific resistance genes, and respond to selection by resistance genes in released wheat cultivars. The wheat cultivar Toropi, developed and grown in Brazil, was noted to have long-lasting leaf rust resistance that was effective only in adult plants. The objectives of this study were to determine the chromosome location of the leaf rust resistance genes derived from Toropi in two populations of recombinant inbred lines in a partial Thatcher wheat background. In the first population, a single gene with major effects on chromosome 5DS that mapped 2.2 centimorgans distal to IWA6289, strongly reduced leaf rust severity in all 3 years of field plot tests. This gene for adult plant leaf rust resistance was designated as Lr78. In the second population, quantitative trait loci (QTL) with small effects on chromosomes 1BL, 3BS, and 4BS were found. These QTL expressed inconsistently over 4 years of field plot tests. The adult plant leaf rust resistance derived from Toropi involved a complex combination of QTL with large and small effects.

Adult plant leaf rust resistance derived from the soft red winter wheat cultivar Caldwell maps to chromosome 3BS

Science.gov (United States)

'Caldwell' is a U.S. soft red winter wheat that has partial, adult plant resistance to the leaf rust pathogen Puccinia triticina. A line of 'Thatcher*2/Caldwell' with adult plant resistance derived from Caldwell was crossed with 'Thatcher' to develop a population of recombinant inbred lines (RILs). ...

Objectives, Outlines, and Preparation for the Resist Tubule Space Experiment to Understand the Mechanism of Gravity Resistance in Plants

Science.gov (United States)

Hoson, Takayuki; Akamatsu, Haruhiko; Soga, Kouichi; Wakabayashi, Kazuyuki; Hashimoto, Hirofumi; Yamashita, Masamichi; Hasegawa, Katsuya; Yano, Sachiko; Omori, Katsunori; Ishioka, Noriaki; Matsumoto, Shohei; Kasahara, Haruo; Shimazu, Toru; A. Baba, Shoji; Hashimoto, Takashi

Gravity resistance is a principal graviresponse in plants. In resistance to hypergravity, the gravity signal may be perceived by the mechanoreceptors located on the plasma membrane, and then transformed and transduced via the structural continuum or physiological continuity of cortical microtubules-plasma membrane-cell wall, leading to an increase in the cell wall rigidity as the final response. The Resist Tubule experiment, which will be conducted in the Kibo Module on the International Space Station, aims to confirm that this hypothesis is applicable to resistance to 1 G gravity. There are two major objectives in the Resist Tubule experiment. One is to quantify the contributions of cortical microtubules to gravity resistance using Arabidopsis tubulin mutants with different degrees of defects. Another objective is to analyze the modifications to dynamics of cortical microtubules and membrane rafts under microgravity conditions on-site by observing green fluorescent protein (GFP)-expressing Arabidopsis lines with the fluorescence microscope in the Kibo. We have selected suitable mutants, developed necessary hardware, and fixed operation procedure for the experiment.

Harzianolide, a novel plant growth regulator and systemic resistance elicitor from Trichoderma harzianum.

Science.gov (United States)

Cai, Feng; Yu, Guanghui; Wang, Ping; Wei, Zhong; Fu, Lin; Shen, Qirong; Chen, Wei

2013-12-01

A detailed understanding of the effect of natural products on plant growth and protection will underpin new product development for plant production. The isolation and characterization of a known secondary metabolite named harzianolide from Trichoderma harzianum strain SQR-T037 were described, and the bioactivity of the purified compound as well as the crude metabolite extract in plant growth promotion and systemic resistance induction was investigated in this study. The results showed that harzianolide significantly promoted tomato seedling growth by up to 2.5-fold (dry weight) at a concentration of 0.1 ppm compared with the control. The result of root scan suggested that Trichoderma secondary metabolites may influence the early stages of plant growth through better root development for the enhancement of root length and tips. Both of the purified harzianolide and crude metabolite extract increased the activity of some defense-related enzymes to response to oxidative stress. Examination of six defense-related gene expression by real-time reverse transcription-PCR analysis revealed that harzianolide induces the expression of genes involved in the salicylic acid (PR1 and GLU) and jasmonate/ethylene (JERF3) signaling pathways while crude metabolite extract inhibited some gene expression (CHI-II and PGIP) related to basal defense in tomato plants. Further experiment showed that a subsequent challenge of harzianolide-pretreated plants with the pathogen Sclerotinia sclerotiorum resulted in higher systemic resistance by the reduction of lesion size. These results indicate that secondary metabolites of Trichoderma spp., like harzianolide, may play a novel role in both plant growth regulation and plant defense responses. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Plant Growth Enhancement, Disease Resistance, and Elemental Modulatory Effects of Plant Probiotic Endophytic Bacillus sp. Fcl1.

Science.gov (United States)

Jayakumar, Aswathy; Krishna, Arathy; Mohan, Mahesh; Nair, Indu C; Radhakrishnan, E K

2018-04-13

Endophytic bacteria have already been studied for their beneficial support to plants to manage both biotic and abiotic stress through an array of well-established mechanisms. They have either direct or indirect impact on mobilizing diverse nutrients and elements from soil to plants. However, detailed insight into the fine-tuning of plant elemental composition by associated microorganism is very limited. In this study, endophytic Bacillus Fcl1 characterized from the rhizome of Curcuma longa was found to have broad range of plant growth-promoting and biocontrol mechanisms. The organism was found to have indole acetic acid and 1-aminocyclopropane-1-carboxylate deaminase production properties along with nitrogen fixation. The Bacillus Fcl1 could also inhibit diverse phytopathogens as confirmed by dual culture and well diffusion. By LC-MS/MS analysis, chemical basis of its antifungal activity has been proved to be due to the production of iturin A and a blend of surfactin compounds. Moreover, the organism was found to induce both plant growth and disease resistance in vivo in model plant system. Because of these experimentally demonstrated multiple plant probiotic features, Bacillus Fcl1 was selected as a candidate organism to study its role in modulation of plant elemental composition. ICP-MS analysis of Bacillus Fcl1-treated plants provided insight into relation of bacterial interaction with elemental composition of plants.

Polycomb Protein OsFIE2 Affects Plant Height and Grain Yield in Rice.

Directory of Open Access Journals (Sweden)

Xianbo Liu

Full Text Available Polycomb group (PcG proteins have been shown to affect growth and development in plants. To further elucidate their role in these processes in rice, we isolated and characterized a rice mutant which exhibits dwarfism, reduced seed setting rate, defective floral organ, and small grains. Map-based cloning revealed that abnormal phenotypes were attributed to a mutation of the Fertilization Independent Endosperm 2 (OsFIE2 protein, which belongs to the PcG protein family. So we named the mutant as osfie2-1. Histological analysis revealed that the number of longitudinal cells in the internodes decreased in osfie2-1, and that lateral cell layer of the internodes was markedly thinner than wild-type. In addition, compared to wild-type, the number of large and small vascular bundles decreased in osfie2-1, as well as cell number and cell size in spikelet hulls. OsFIE2 is expressed in most tissues and the coded protein localizes in both nucleus and cytoplasm. Yeast two-hybrid and bimolecular fluorescence complementation assays demonstrated that OsFIE2 interacts with OsiEZ1 which encodes an enhancer of zeste protein previously identified as a histone methylation enzyme. RNA sequencing-based transcriptome profiling and qRT-PCR analysis revealed that some homeotic genes and genes involved in endosperm starch synthesis, cell division/expansion and hormone synthesis and signaling are differentially expressed between osfie2-1 and wild-type. In addition, the contents of IAA, GA3, ABA, JA and SA in osfie2-1 are significantly different from those in wild-type. Taken together, these results indicate that OsFIE2 plays an important role in the regulation of plant height and grain yield in rice.

Do forest soil microbes have the potential to resist plant invasion? A case study in Dinghushan Biosphere Reserve (South China)

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Chen, Bao-Ming; Li, Song; Liao, Hui-Xuan; Peng, Shao-Lin

2017-05-01

Successful invaders must overcome biotic resistance, which is defined as the reduction in invasion success caused by the resident community. Soil microbes are an important source of community resistance to plant invasions, and understanding their role in this process requires urgent investigation. Therefore, three forest communities along successional stages and four exotic invasive plant species were selected to test the role of soil microbes of three forest communities in resisting the exotic invasive plant. Our results showed that soil microbes from a monsoon evergreen broadleaf forest (MEBF) (late-successional stage) had the greatest resistance to the invasive plants. Only the invasive species Ipomoea triloba was not sensitive to the three successional forest soils. Mycorrhizal fungi in early successional forest Pinus massonina forest (PMF) or mid-successional forest pine-broadleaf mixed forest (PBMF) soil promoted the growth of Mikania micrantha and Eupatorium catarium, but mycorrhizal fungi in MEBF soil had no significant effects on their growth. Pathogens plus other non-mycorrhizal microbes in MEBF soil inhibited the growth of M. micrantha and E. catarium significantly, and only inhibited root growth of E. catarium when compared with those with mycorrhizal fungi addition. The study suggest that soil mycorrhizal fungi of early-mid-successional forests benefit invasive species M. micrantha and E. catarium, while soil pathogens of late-successional forest may play an important role in resisting M. micrantha and E. catarium. The benefit and resistance of the soil microbes are dependent on invasive species and related to forest succession. The study gives a possible clue to control invasive plants by regulating soil microbes of forest community to resist plant invasion.

The Genetic Architecture of Barley Plant Stature

Science.gov (United States)

Alqudah, Ahmad M.; Koppolu, Ravi; Wolde, Gizaw M.; Graner, Andreas; Schnurbusch, Thorsten

2016-01-01

Plant stature in temperate cereals is predominantly controlled by tillering and plant height as complex agronomic traits, representing important determinants of grain yield. This study was designed to reveal the genetic basis of tillering at five developmental stages and plant height at harvest in 218 worldwide spring barley (Hordeum vulgare L.) accessions under greenhouse conditions. The accessions were structured based on row-type classes [two- vs. six-rowed] and photoperiod response [photoperiod-sensitive (Ppd-H1) vs. reduced photoperiod sensitivity (ppd-H1)]. Phenotypic analyses of both factors revealed profound between group effects on tiller development. To further verify the row-type effect on the studied traits, Six-rowed spike 1 (vrs1) mutants and their two-rowed progenitors were examined for tiller number per plant and plant height. Here, wild-type (Vrs1) plants were significantly taller and had more tillers than mutants suggesting a negative pleiotropic effect of this row-type locus on both traits. Our genome-wide association scans further revealed highly significant associations, thereby establishing a link between the genetic control of row-type, heading time, tillering, and plant height. We further show that associations for tillering and plant height are co-localized with chromosomal segments harboring known plant stature-related phytohormone and sugar-related genes. This work demonstrates the feasibility of the GWAS approach for identifying putative candidate genes for improving plant architecture. PMID:27446200

The Effect of NPP's Stack Height to Radiation Dose

International Nuclear Information System (INIS)

Pandi, Liliana Yetta; Rohman, Budi

2003-01-01

The purpose of dose calculation for accidents is to analyze the capability of NPP to maintain the safety of public and workers in case an accident occurs on the Plant in a site. This paper calculates the Loss of Coolant Accident in PWR plant. The calculation results shows that no risks of serious radiation exposure are given to the neighboring public even if such a large accident occurred, and the effect of stack height can be predicted by analysis of the calculation results. The whole dose is calculated for some location (100 m, 300 m, 500 m, 700 m, 900 m, 1500 m, and 2000 m) with three difference stack height i.e. 0 m, 40 m and 100 m. The result of the whole dose calculation is under permitted criteria for whole dose : 0.25 Sv and thyroid dose : 3.0 Sv. The calculation of radiation dose in this paper use EEDCDQ code

Confirmation of the seismic resistance of nuclear power plant equipment after assembly

International Nuclear Information System (INIS)

Kaznovsky, P. S.; Kaznovsky, A. P.; Saakov, E. S.; Ryasnyj, S. I.

2013-01-01

It is shown that the natural frequencies and damping decrements of nuclear power plant equipment can only be determined experimentally and directly at the power generation units (reactors) of nuclear power plants under real disassembly conditions for the equipment, piping network, thermal insulation, etc. A computational experimental method is described in which the natural frequencies and damping decrements are determined in the field and the seismic resistance is reevaluated using these values. This method is the basis of the standards document “Methods for confirming the dynamic characteristics of systems and components of the generating units of nuclear power plants which are important for safety” prepared and introduced in 2012.

Effects of silicon on plant resistance to environmental stresses: review

Science.gov (United States)

Balakhnina, T.; Borkowska, A.

2013-03-01

The role of exogenous silicon in enhancing plant resistance to various abiotic stressors: salinity, drought, metal toxicities and ultraviolet radiation are presented. The data on possible involvement of silicon in reducing the reactive oxygen species generation, intensity of lipid peroxidation, and in some cases, increasing the activity of enzymes of the reactive oxygen species detoxificators: superoxide dismutase, ascorbate peroxidase, glutathione reductase, guaiacol peroxidase and catalase are analyzed.

Random Plant Viral Variants Attain Temporal Advantages During Systemic Infections and in Turn Resist other Variants of the Same Virus.

Science.gov (United States)

Zhang, Xiao-Feng; Guo, Jiangbo; Zhang, Xiuchun; Meulia, Tea; Paul, Pierce; Madden, Laurence V; Li, Dawei; Qu, Feng

2015-10-20

Infection of plants with viruses containing multiple variants frequently leads to dominance by a few random variants in the systemically infected leaves (SLs), for which a plausible explanation is lacking. We show here that SL dominance by a given viral variant is adequately explained by its fortuitous lead in systemic spread, coupled with its resistance to superinfection by other variants. We analyzed the fate of a multi-variant turnip crinkle virus (TCV) population in Arabidopsis and N. benthamiana plants. Both wild-type and RNA silencing-defective plants displayed a similar pattern of random dominance by a few variant genotypes, thus discounting a prominent role for RNA silencing. When introduced to plants sequentially as two subpopulations, a twelve-hour head-start was sufficient for the first set to dominate. Finally, SLs of TCV-infected plants became highly resistant to secondary invasions of another TCV variant. We propose that random distribution of variant foci on inoculated leaves allows different variants to lead systemic movement in different plants. The leading variants then colonize large areas of SLs, and resist the superinfection of lagging variants in the same areas. In conclusion, superinfection resistance is the primary driver of random enrichment of viral variants in systemically infected plants.

Effect of selected local medicinal plants on the asexual blood stage of chloroquine resistant Plasmodium falciparum.

Science.gov (United States)

Mohd Abd Razak, Mohd Ridzuan; Afzan, Adlin; Ali, Rosnani; Amir Jalaluddin, Nur Fasihah; Wasiman, Mohd Isa; Shiekh Zahari, Siti Habsah; Abdullah, Noor Rain; Ismail, Zakiah

2014-12-15

The development of resistant to current antimalarial drugs is a major challenge in achieving malaria elimination status in many countries. Therefore there is a need for new antimalarial drugs. Medicinal plants have always been the major source for the search of new antimalarial drugs. The aim of this study was to screen selected Malaysian medicinal plants for their antiplasmodial properties. Each part of the plants were processed, defatted by hexane and sequentially extracted with dichloromethane, methanol and water. The antiplasmodial activities of 54 plant extracts from 14 species were determined by Plasmodium falciparum Histidine Rich Protein II ELISA technique. In order to determine the selectivity index (SI), all plant extracts demonstrating a good antiplasmodial activity were tested for their cytotoxicity activity against normal Madin-Darby Bovine Kidney (MDBK) cell lines by 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Twenty three extracts derived from Curcuma zedoaria (rhizome), Curcuma aeruginosa (rhizome), Alpinia galanga (rhizome), Morinda elliptica (leaf), Curcuma mangga (rhizome), Elephantopus scaber (leaf), Vitex negundo (leaf), Brucea javanica (leaf, root and seed), Annona muricata (leaf), Cinnamomun iners (leaf) and Vernonia amygdalina (leaf) showed promising antiplasmodial activities against the blood stage chloroquine resistant P. falciparum (EC50 toxicity effect to MDBK cells in vitro (SI ≥10). The extracts belonging to eleven plant species were able to perturb the growth of chloroquine resistant P. falciparum effectively. The findings justified the bioassay guided fractionation on these plants for the search of potent antimalarial compounds or formulation of standardized extracts which may enhance the antimalarial effect in vitro and in vivo.

Constitutive expression of a fungus-inducible carboxylesterase improves disease resistance in transgenic pepper plants.

Science.gov (United States)

Ko, Moonkyung; Cho, Jung Hyun; Seo, Hyo-Hyoun; Lee, Hyun-Hwa; Kang, Ha-Young; Nguyen, Thai Son; Soh, Hyun Cheol; Kim, Young Soon; Kim, Jeong-Il

2016-08-01

Resistance against anthracnose fungi was enhanced in transgenic pepper plants that accumulated high levels of a carboxylesterase, PepEST in anthracnose-susceptible fruits, with a concurrent induction of antioxidant enzymes and SA-dependent PR proteins. A pepper esterase gene (PepEST) is highly expressed during the incompatible interaction between ripe fruits of pepper (Capsicum annuum L.) and a hemibiotrophic anthracnose fungus (Colletotrichum gloeosporioides). In this study, we found that exogenous application of recombinant PepEST protein on the surface of the unripe pepper fruits led to a potentiated state for disease resistance in the fruits, including generation of hydrogen peroxide and expression of pathogenesis-related (PR) genes that encode mostly small proteins with antimicrobial activity. To elucidate the role of PepEST in plant defense, we further developed transgenic pepper plants overexpressing PepEST under the control of CaMV 35S promoter. Molecular analysis confirmed the establishment of three independent transgenic lines carrying single copy of transgenes. The level of PepEST protein was estimated to be approximately 0.002 % of total soluble protein in transgenic fruits. In response to the anthracnose fungus, the transgenic fruits displayed higher expression of PR genes, PR3, PR5, PR10, and PepThi, than non-transgenic control fruits did. Moreover, immunolocalization results showed concurrent localization of ascorbate peroxidase (APX) and PR3 proteins, along with the PepEST protein, in the infected region of transgenic fruits. Disease rate analysis revealed significantly low occurrence of anthracnose disease in the transgenic fruits, approximately 30 % of that in non-transgenic fruits. Furthermore, the transgenic plants also exhibited resistance against C. acutatum and C. coccodes. Collectively, our results suggest that overexpression of PepEST in pepper confers enhanced resistance against the anthracnose fungi by activating the defense signaling

A review on the complexity of insect-plant interactions under varying levels of resources and host resistance: the case of Myzus persicae-Prunus persica

Directory of Open Access Journals (Sweden)

Verdugo, JA.

2016-01-01

Full Text Available Introduction. Insect-plant interactions are affected directly or indirectly by stress factors. The effect of environmental resource availability on insect-plant interactions is here reviewed. Subsequently, the analysis focuses on aphid-host plant interactions, particularly in the system composed by the green peach aphid Myzus persicae and its primary host plant Prunus persica. Literature. Plant defenses arise in two ways: resistance and tolerance, both are affected by abiotic factors. The information gathered from studies (n = 29 on plant-aphid interactions addressing the reduction in water availability on plant resistance, showed that in 41,4% of the studies, drought stress elicits lower resistance, while 34.5%, 20.1% and 3.4%, showed higher, no change and conditional effects on plant resistance, respectively. Conclusions. Water stress elicits mixed effects on plant resistance to aphids. However, the literature review also suggests that cultural practices play a role in the fate of the peach-aphid interactions, whereas the development of predictive models aimed to assist crop-pest management systems still requires more basic information. Aphid responses to plant defenses under stressed conditions are still largely unexplored.

Survey of pollution-resistant plants and their cultivating techniques; Osen busshitsu taisei shokubutsu to sono shokusai gijutsu ni kansuru chosa

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

The reduction of forests due to environmental pollution has been surveyed, to investigate the pollution-resistant plants and solid microorganisms. In Japan, the blight of needle-leaf trees (pine and momi fir) and of Japanese oak has occurred, and blight of some other trees, such as wild cherry trees, Japanese apricot trees, birch, Japanese cedar, cypress and bamboo, has been reported from various regions. In this article, plants reported to be resistant to pollutants are listed, and the physiological features of these plants are described. Furthermore, to develop pollution-resistant plants, reports relating to clarification of the mechanism of resistance development and the genes involved are reviewed. Microorganisms which symbioses for roots support these root functions. They also suppress the activity of pathogenic microorganisms and improve the environment around the roots, thus helping plants to grow normally. The roles played by symbiotic microorganisms and how to utilize these organisms are discussed. Their functions in coping with acid rain and heavy metal pollution, and how to utilize such functions are also discussed. 707 refs., 13 figs., 13 tabs.

Thermal activation of current in an inhomogeneous Schottky diode with a Gaussian distribution of barrier height

International Nuclear Information System (INIS)

Guo-Ping, Ru; Rong, Yu; Yu-Long, Jiang; Gang, Ruan

2010-01-01

This paper investigates the thermal activation behaviour of current in an inhomogeneous Schottky diode with a Gaussian distribution of barrier height by numerical simulation. The analytical Gaussian distribution model predicted that the I-V-T curves may intersect with the possibility of the negative thermal activation of current, but may be contradictory to the thermionic emission mechanism in a Schottky diode. It shows that the cause of the unphysical phenomenon is related to the incorrect calculation of current across very low barriers. It proposes that junction voltage V j , excluding the voltage drop across series resistance from the external bias, is a crucial parameter for correct calculation of the current across very low barriers. For correctly employing the thermionic emission model, V j needs to be smaller than the barrier height ø. With proper scheme of series resistance connection where the condition of V j > ø is guaranteed, I-V-T curves of an inhomogeneous Schottky diode with a Gaussian distribution of barrier height have been simulated, which demonstrate normal thermal activation. Although the calculated results exclude the intersecting possibility of I-V-T curves with an assumption of temperature-independent series resistance, it shows that the intersecting is possible when the series resistance has a positive temperature coefficient. Finally, the comparison of our numerical and analytical results indicates that the analytical Gaussian distribution model is valid and accurate in analysing I-V-T curves only for small barrier height inhomogeneity. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Induced mutations and in vitro culture techniques for improving crop plant resistance to diseases

International Nuclear Information System (INIS)

1993-12-01

This co-ordinated research program was undertaken in search of in vitro techniques to increase the resistance of plants to disease. The studies performed under the program ranged from the preparation of materials for mass screening to screening of mutagen-treated cells, tissues, organs or plantlets for resistance to viruses, fungi and other pathogens. The characteristics of the resulting mutants were evaluated to determine the relevance of these techniques for plant breeding. The present document contains the papers presented at the final Research Co-ordination Meeting of the program, as well as a summary of the conclusions and recommendations drawn from the work. The nine individual papers have been input separately to the database. Refs, figs and tabs

Methyl esterification of pectin plays a role during plant-pathogen interactions and affects plant resistance to diseases.

Science.gov (United States)

Lionetti, Vincenzo; Cervone, Felice; Bellincampi, Daniela

2012-11-01

The cell wall is a complex structure mainly composed by a cellulose-hemicellulose network embedded in a cohesive pectin matrix. Pectin is synthesized in a highly methyl esterified form and is de-esterified in muro by pectin methyl esterases (PMEs). The degree and pattern of methyl esterification affect the cell wall structure and properties with consequences on both the physiological processes of the plants and their resistance to pathogens. PME activity displays a crucial role in the outcome of the plant-pathogen interactions by making pectin more susceptible to the action of the enzymes produced by the pathogens. This review focuses on the impact of pectin methyl esterification in plant-pathogen interactions and on the dynamic role of its alteration during pathogenesis. Copyright © 2012 Elsevier GmbH. All rights reserved.

Antibacterial activity of selected medicinal plants against multiple antibiotic resistant uropathogens: a study from Kolli Hills, Tamil Nadu, India.

Science.gov (United States)

Narayanan, A S; Raja, S S S; Ponmurugan, K; Kandekar, S C; Natarajaseenivasan, K; Maripandi, A; Mandeel, Q A

2011-09-01

The increasing incidence of antibiotic resistance among bacterial pathogens necessitates medicinal plants as an alternate therapy in restricting the resistant infectious organisms. In this primitive study, the antibiotic resistance of organisms isolated from urinary tract infected patients was evaluated using the National Committee for Clinical Laboratory Standards (NCCLS) method and Multiple Antibiotic Resistance (MAR) index values, and the MAR values was also calculated for plant extracts. The 10 common medicinal plants collected from Kolli hills, Namakkal, south India were extracted using the chloroform, methanol, acetone, ethanol and saponification procedure. The efficacy of the extracts on the uropathogens was tested by agar disc diffusion method in order to analyse the inhibitory activity of plant extract on the organisms. Azadiracta indica A. Juss., Tinospora cordifolia (Wild.) and Euphorbia hirta Linn. exhibited high inhibitory activity against most of the 11 tested organisms followed by Cassia javanica Linn. and Phyllanthus niruri Linn. The maximum zone size of 46.3 mm was exhibited by methanol extract of P. niruri Linn. against Pseudomonas aeruginosa. Asparagus racemosus Willd. and Eupatorium triplinerve Vahl had the least activity against resistant pathogens. Saponified lipids of most of the plants exhibited maximum antibacterial activity. Among the tested organisms, P. aeruginosa and Staphylococcus epidermidis were the most susceptible and Serratia marcescens, Enterobacter cloaceae, Citrobacter koseri, and Citrobacter freundii were the least inhibited by most of the extracts of medicinal plants. It is concluded that revised antibiotic policies and more importantly the development of herbal medicine as an alternative may be incorporated in urological practice.

Produtividade de culturas e resistência à penetração de Argissolo Vermelho sob diferentes manejos Yield of crops and soil resistance to penetration of the Alfisol under different management

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Cláudia Liane Rodrigues de Lima

2010-01-01

Full Text Available O objetivo deste trabalho foi avaliar a relação entre parâmetros de plantas de soja e feijão e a resistência do solo à penetração de Argissolo Vermelho distrófico arênico sob semeadura direta e convencional. Em experimento implantado em 1989 em semeadura direta, foram aplicadas diferentes passadas de máquina de 10 Mg e realizados diferentes preparos do solo em delineamento inteiramente casualizado. Foram quantificados o índice de velocidade de emergência, o índice de área foliar, a altura e a produtividade de grãos de soja e de feijão e a resistência do solo à penetração. O índice de área foliar, a altura e a produtividade do feijão são influenciados pela resistência do solo à penetração em 46, 51 e 59%, respectivamente, enquanto 55% da variação da altura da soja é explicada pela resistência à penetração. Indica-se um valor crítico de resistência à penetração de aproximadamente 1,7 e 1,9 MPa no que se refere ao crescimento e à produtividade de grãos de feijão e de soja, respectivamente.The objective of this work was to evaluate the relationship among soybean and bean plant parameters and soil resistance to penetration of an Alfisol under no-tillage and conventional systems. In an experiment deployed under no-tillage in 1989, different wheel tracks of a 10-Mg machine were applied and different soil management systems were used in completely randomized design. Emergence speed index, foliar area index, height and yield of soybean and bean crops and soil resistance to penetration were quantified. The influence of soil resistance to penetration in foliar area index, height and productivity of beans is of 46, 51 and 59% respectively, whereas 55% of the height variation in soybean is explained by soil resistance to penetration. The critical value of soil resistance to penetration indicated for bean and soybean growth and yield is of approximately 1.7 and 1.9 MPa respectively.

Resistance to cereal rusts at the plant cell wall - what can we learn from other host-pathogen systems?

NARCIS (Netherlands)

Collins, N.C.; Niks, R.E.; Schulze-Lefert, P.

2007-01-01

The ability of plant cells to resist invasion by pathogenic fungi at the cell periphery (pre-invasion resistance) differs from other types of resistance that are generally triggered after parasite entry and during differentiation of specialised intracellular feeding structures. Genetic sources of

Plant Growth, Antibiotic Uptake, and Prevalence of Antibiotic Resistance in an Endophytic System of Pakchoi under Antibiotic Exposure

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Hao Zhang

2017-11-01

Full Text Available Antibiotic contamination in agroecosystems may cause serious problems, such as the proliferation of various antibiotic resistant bacteria and the spreading of antibiotic resistance genes (ARGs in the environment or even to human beings. However, it is unclear whether environmental antibiotics, antibiotic resistant bacteria, and ARGs can directly enter into, or occur in, the endophytic systems of plants exposed to pollutants. In this study, a hydroponic experiment exposing pakchoi (Brassica chinensis L. to tetracycline, cephalexin, and sulfamethoxazole at 50% minimum inhibitory concentration (MIC levels and MIC levels, respectively, was conducted to explore plant growth, antibiotic uptake, and the development of antibiotic resistance in endophytic systems. The three antibiotics promoted pakchoi growth at 50% MIC values. Target antibiotics at concentrations ranging from 6.9 to 48.1 µg·kg−1 were detected in the treated vegetables. Additionally, the rates of antibiotic-resistant endophytic bacteria to total cultivable endophytic bacteria significantly increased as the antibiotics accumulated in the plants. The detection and quantification of ARGs indicated that four types, tetX, blaCTX-M, and sul1 and sul2, which correspond to tetracycline, cephalexin, and sulfamethoxazole resistance, respectively, were present in the pakchoi endophytic system and increased with the antibiotic concentrations. The results highlight a potential risk of the development and spread of antibiotic resistance in vegetable endophytic systems.

Plant Growth, Antibiotic Uptake, and Prevalence of Antibiotic Resistance in an Endophytic System of Pakchoi under Antibiotic Exposure.

Science.gov (United States)

Zhang, Hao; Li, Xunan; Yang, Qingxiang; Sun, Linlin; Yang, Xinxin; Zhou, Mingming; Deng, Rongzhen; Bi, Linqian

2017-11-03

Antibiotic contamination in agroecosystems may cause serious problems, such as the proliferation of various antibiotic resistant bacteria and the spreading of antibiotic resistance genes (ARGs) in the environment or even to human beings. However, it is unclear whether environmental antibiotics, antibiotic resistant bacteria, and ARGs can directly enter into, or occur in, the endophytic systems of plants exposed to pollutants. In this study, a hydroponic experiment exposing pakchoi ( Brassica chinensis L.) to tetracycline, cephalexin, and sulfamethoxazole at 50% minimum inhibitory concentration (MIC) levels and MIC levels, respectively, was conducted to explore plant growth, antibiotic uptake, and the development of antibiotic resistance in endophytic systems. The three antibiotics promoted pakchoi growth at 50% MIC values. Target antibiotics at concentrations ranging from 6.9 to 48.1 µg·kg -1 were detected in the treated vegetables. Additionally, the rates of antibiotic-resistant endophytic bacteria to total cultivable endophytic bacteria significantly increased as the antibiotics accumulated in the plants. The detection and quantification of ARGs indicated that four types, tet X, bla CTX-M , and sul 1 and sul 2, which correspond to tetracycline, cephalexin, and sulfamethoxazole resistance, respectively, were present in the pakchoi endophytic system and increased with the antibiotic concentrations. The results highlight a potential risk of the development and spread of antibiotic resistance in vegetable endophytic systems.

Abundances of tetracycline, sulphonamide and beta-lactam antibiotic resistance genes in conventional wastewater treatment plants (WWTPs with different waste load.

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Mailis Laht

Full Text Available Antibiotics and antibiotic resistant bacteria enter wastewater treatment plants (WWTPs, an environment where resistance genes can potentially spread and exchange between microbes. Several antibiotic resistance genes (ARGs were quantified using qPCR in three WWTPs of decreasing capacity located in Helsinki, Tallinn, and Tartu, respectively: sulphonamide resistance genes (sul1 and sul2, tetracycline resistance genes (tetM and tetC, and resistance genes for extended spectrum beta-lactams (blaoxa-58, blashv-34, and blactx-m-32. To avoid inconsistencies among qPCR assays we normalised the ARG abundances with 16S rRNA gene abundances while assessing if the respective genes increased or decreased during treatment. ARGs were detected in most samples; sul1, sul2, and tetM were detected in all samples. Statistically significant differences (adjusted p<0.01 between the inflow and effluent were detected in only four cases. Effluent values for blaoxa-58 and tetC decreased in the two larger plants while tetM decreased in the medium-sized plant. Only blashv-34 increased in the effluent from the medium-sized plant. In all other cases the purification process caused no significant change in the relative abundance of resistance genes, while the raw abundances fell by several orders of magnitude. Standard water quality variables (biological oxygen demand, total phosphorus and nitrogen, etc. were weakly related or unrelated to the relative abundance of resistance genes. Based on our results we conclude that there is neither considerable enrichment nor purification of antibiotic resistance genes in studied conventional WWTPs.

Manduca sexta recognition and resistance among allopolyploid Nicotiana host plants

OpenAIRE

Lou, Yonggen; Baldwin, Ian T.

2003-01-01

Allopolyploid speciation occurs instantly when the genomes of different species combine to produce self-fertile offspring and has played a central role in the evolution of higher plants, but its consequences for adaptive responses are unknown. We compare herbivore-recognition and -resistance responses of the diploid species and putative ancestral parent Nicotiana attenuata with those of the two derived allopolyploid species Nicotiana clevelandii and Nicotiana bigelovii. Manduca sexta larvae a...

Plant community resistance to invasion by Bromus species: The roles of community attributes, Bromus interactions with plant communities, and Bromus traits [Chapter 10

Science.gov (United States)

Jeanne C. Chambers; Matthew J. Germino; Jayne Belnap; Cynthia S. Brown; Eugene W. Schupp; Samuel B. St. Clair

2016-01-01

The factors that determine plant community resistance to exotic annual Bromus species (Bromus hereafter) are diverse and context specific. They are influenced by the environmental characteristics and attributes of the community, the traits of Bromus species, and the direct and indirect interactions of Bromus with the plant community. Environmental factors, in...

Transgenic fertile Scoparia dulcis L., a folk medicinal plant, conferred with a herbicide-resistant trait using an Ri binary vector.

Science.gov (United States)

Yamazaki, M; Son, L; Hayashi, T; Morita, N; Asamizu, T; Mourakoshi, I; Saito, K

1996-01-01

Transgenic herbicide-resistant Scoparia dulcis plants were obtained by using an Ri binary vector system. The chimeric bar gene encoding phosphinothricin acetyltransferase flanked by the promoter for cauliflower mosaic virus 35S RNA and the terminal sequence for nopaline synthase was introduced in the plant genome by Agrobacterium-mediated transformation by means of scratching young plants. Hairy roots resistant to bialaphos were selected and plantlets (R0) were regenerated. Progenies (S1) were obtained by self-fertilization. The transgenic state was confirmed by DNA-blot hybridization and assaying of neomycin phosphotransferase II. Expression of the bar gene in the transgenic R0 and S1 progenies was indicated by the activity of phosphinothricin acetyltransferase. Transgenic plants accumulated scopadulcic acid B, a specific secondary metabolite of S. dulcis, in amounts of 15-60% compared with that in normal plants. The transgenic plants and progenies showed resistant trait towards bialaphos and phosphinothricin. These results suggest that an Ri binary system is one of the useful tools for the transformation of medicinal plants for which a regeneration protocol has not been established.

Fate of antibiotic resistance genes within the microbial communities of three waste water treatment plants

OpenAIRE

Di Cesare, Andrea; Eckert, Ester; D'Urso, Silvia; Doppelbauer, Julia; Corno, Gianluca

2016-01-01

Although Waste Water Treatment Plant (WWTP) are designed to reduce the biological pollution of urban waters, they lack a specific action against antibiotic resistance bacteria (ARB) or antibiotic resistance genes (ARGs). Nowadays, it is well documented that WWTPs constitute a reservoir of antibiotic resistances and, in some cases, they can be a favorable environment for the selection of ARB. This represent a serious concern for the public health, because the effluents of the WWTPs can be reus...

Auxinic herbicides, mechanisms of action, and weed resistance: A look into recent plant science advances

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Pedro Jacob Christoffoleti

2015-08-01

Full Text Available Auxin governs dynamic cellular processes involved at several stages of plant growth and development. In this review, we discuss the mechanisms employed by auxin in light of recent scientific advances, with a focus on synthetic auxins as herbicides and synthetic auxin resistance mechanisms. Two auxin receptors were reported. The plasma membrane receptor ABP1 (Auxin Binding Protein 1 alters the structure and arrangement of actin filaments and microtubules, leading to plant epinasty and reducing peroxisomes and mitochondria mobility in the cell environment. The second auxin receptor is the gene transcription pathway regulated by the SCFTir/AFB ubiquitination complex, which destroys transcription repressor proteins that interrupt Auxin Response Factor (ARF activation. As a result mRNA related with Abscisic Acid (ABA and ethylene are transcribed, producing high quantities of theses hormones. Their associated action leads to high production of Reactive Oxygen Species (ROS, leading to tissue and plant death. Recently, another ubiquitination pathway which is described as a new auxin signaling route is the F-box protein S-Phase Kinase-Associated Protein 2A (SKP2A. It is active in cell division regulation and there is evidence that auxin herbicides can deregulate the SKP2A pathway, which leads to severe defects in plant development. In this discussion, we propose that SFCSKP2A auxin binding site alteration could be a new auxinic herbicide resistance mechanism, a concept which may contribute to the current progress in plant biology in its quest to clarify the many questions that still surround auxin herbicide mechanisms of action and the mechanisms of weed resistance.

Growth in Total Height and Its Components and Cardiometabolic Health in Childhood

DEFF Research Database (Denmark)

Haugaard, Line Klingen; Baker, Jennifer Lyn; Perng, Wei

2016-01-01

BACKGROUND: Short stature or short legs is associated with cardiometabolic disease. Few studies have addressed this issue in children, incorporated repeated measures, or studied modern cohorts. METHODS: We examined if change in total height, leg length and trunk length between two time points from...... was a cardiometabolic risk score based on sex-specific internal z-scores for systolic blood pressure, waist circumference, homeostatic model assessment of insulin resistance, triglycerides and high-density lipoprotein-cholesterol. RESULTS: Mean (SD) total height was 97.9 (4.5) cm in boys and 97.1 (4.7) cm in girls...... in early childhood and 129.1 (7.2) cm in boys and 128.3 (7.9) cm in girls in mid-childhood. Trunk length constituted about half of total height. In linear regression models adjusted for parental anthropometry and socio-demographics, faster growth in total height, leg length and particularly trunk length...

Effect of multiple metal resistant bacteria from contaminated lake sediments on metal accumulation and plant growth

International Nuclear Information System (INIS)

Li, Kefeng; Ramakrishna, Wusirika

2011-01-01

Naturally occurring bacteria play an important role in bioremediation of heavy metal pollutants in soil and wastewater. This study identified high levels of resistance to zinc, cesium, lead, arsenate and mercury in eight copper resistant Pseudomonas strains previously isolated from Torch Lake sediment. These strains showed variable susceptibility to different antibiotics. Furthermore, these metal resistant strains were capable of bioaccumulation of multiple metals and solubilization of copper. Bacterial strains TLC 3-3.5-1 and TLC 6-6.5-1 showed high bioaccumulation ability of Zn (up to 15.9 mg/g dry cell) and Pb (80.7 mg/g dry cell), respectively. All the strains produced plant growth promoting indole-3-acetic acid (IAA), iron chelating siderophore and solubilized mineral phosphate and metals. The effect of bacterial inoculation on plant growth and copper uptake by maize (Zea mays) and sunflower (Helianthus annuus) was investigated using one of the isolates (Pseudomonas sp. TLC 6-6.5-4) with higher IAA production and phosphate and metal soubilization, which resulted in a significant increase in copper accumulation in maize and sunflower, and an increase in the total biomass of maize. The multiple metal-resistant bacterial isolates characterized in our study have potential applications for remediation of metal contaminated soils in combination with plants and metal contaminated water.

Effect of multiple metal resistant bacteria from contaminated lake sediments on metal accumulation and plant growth

Energy Technology Data Exchange (ETDEWEB)

Li, Kefeng [Department of Biological Sciences, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 (United States); Ramakrishna, Wusirika, E-mail: wusirika@mtu.edu [Department of Biological Sciences, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 (United States)

2011-05-15

Naturally occurring bacteria play an important role in bioremediation of heavy metal pollutants in soil and wastewater. This study identified high levels of resistance to zinc, cesium, lead, arsenate and mercury in eight copper resistant Pseudomonas strains previously isolated from Torch Lake sediment. These strains showed variable susceptibility to different antibiotics. Furthermore, these metal resistant strains were capable of bioaccumulation of multiple metals and solubilization of copper. Bacterial strains TLC 3-3.5-1 and TLC 6-6.5-1 showed high bioaccumulation ability of Zn (up to 15.9 mg/g dry cell) and Pb (80.7 mg/g dry cell), respectively. All the strains produced plant growth promoting indole-3-acetic acid (IAA), iron chelating siderophore and solubilized mineral phosphate and metals. The effect of bacterial inoculation on plant growth and copper uptake by maize (Zea mays) and sunflower (Helianthus annuus) was investigated using one of the isolates (Pseudomonas sp. TLC 6-6.5-4) with higher IAA production and phosphate and metal soubilization, which resulted in a significant increase in copper accumulation in maize and sunflower, and an increase in the total biomass of maize. The multiple metal-resistant bacterial isolates characterized in our study have potential applications for remediation of metal contaminated soils in combination with plants and metal contaminated water.

Concordant preferences for actual height and facial cues to height

OpenAIRE

Re, Daniel Edward; Perrett, David I.

2012-01-01

Physical height has a well-documented effect on human mate preferences. In general, both sexes prefer opposite-sex romantic relationships in which the man is taller than the woman, while individual preferences for height are affected by a person’s own height. Research in human mate choice has demonstrated that attraction to facial characteristics, such as facial adiposity, may reflect references for body characteristics. Here, we tested preferences for facial cues to height. In general, incre...

Data mining and influential analysis of gene expression data for plant resistance gene identification in tomato (Solanum lycopersicum

Directory of Open Access Journals (Sweden)

Francisco Torres-Avilés

2014-03-01

Conclusion: Application of different statistical analyses to detect potential resistance genes reliably has shown to conduct interesting results that improve knowledge on molecular mechanisms of plant resistance to pathogens.

Proportional odds model applied to mapping of disease resistance genes in plants

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Maria Helena Spyrides-Cunha

2000-03-01

Full Text Available Molecular markers have been used extensively to map quantitative trait loci (QTL controlling disease resistance in plants. Mapping is usually done by establishing a statistical association between molecular marker genotypes and quantitative variations in disease resistance. However, most statistical approaches require a continuous distribution of the response variable, a requirement not always met since evaluation of disease resistance is often done using visual ratings based on an ordinal scale of disease severity. This paper discusses the application of the proportional odds model to the mapping of disease resistance genes in plants amenable to expression as ordinal data. The model was used to map two resistance QTL of maize to Puccinia sorghi. The microsatellite markers bngl166 and bngl669, located on chromosomes 2 and 8, respectively, were used to genotype F2 individuals from a segregating population. Genotypes at each marker locus were then compared by assessing disease severity in F3 plants derived from the selfing of each genotyped F2 plant based on an ordinal scale severity. The residual deviance and the chi-square score statistic indicated a good fit of the model to the data and the odds had a constant proportionality at each threshold. Single-marker analyses detected significant differences among marker genotypes at both marker loci, indicating that these markers were linked to disease resistance QTL. The inclusion of the interaction term after single-marker analysis provided strong evidence of an epistatic interaction between the two QTL. These results indicate that the proportional odds model can be used as an alternative to traditional methods in cases where the response variable consists of an ordinal scale, thus eliminating the problems of heterocedasticity, non-linearity, and the non-normality of residuals often associated with this type of data.Marcadores moleculares têm sido extensivamente usados para o mapeamento de loci de

PERFORMANCE OF YIELD AND YIELD CONTRIBUTING CHARACTERISTICS OF BC2F3 POPULATION WITH ADDITION OF BLAST RESISTANT GENE

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Muhammad Mahmudul Hasan

2015-10-01

Full Text Available ABSTRACTThe study was carried out in the University Putra Malaysia (UPM Rice Research Centre to evaluate the yield performance of newly developed selected blast resistant plants of BC2F3 generations derived from a cross between MR263, a high yielding rice variety but blast susceptible and Pongsu Seribu 1, donor with blast resistant (Pi-7(tand Pi-d (t1, Pir2-3(tgenes and qLN2 QTL, Malaysian local variety. On the basis of assessed traits, the plants 12, 6, 7, 5, 21, 22, 5, 26, 11, 8, 10, 13 and 15 had the higher yield, blast resistant and good morphological traits. More than 70% heritability was found in days to maturity, plant height, tiller numbers per hill, and panicle per hill, 80% heritability was found in filled grain and yield per hill and more than 90% heritability was found in grain length, grain width and seed weight. Cluster analysis based on the traits grouped 30 plants along with MR263 into seven clusters. According to PCA, the first four principal components account for about 69.3% total variation for all measured traits and exhibited high correlation among the characteristics analyzed.

Transgenic plants expressing the AaIT/GNA fusion protein show increased resistance and toxicity to both chewing and sucking pests.

Science.gov (United States)

Liu, Shu-Min; Li, Jie; Zhu, Jin-Qi; Wang, Xiao-Wei; Wang, Cheng-Shu; Liu, Shu-Sheng; Chen, Xue-Xin; Li, Sheng

2016-04-01

The adoption of pest-resistant transgenic plants to reduce yield losses and decrease pesticide use has been successful. To achieve the goal of controlling both chewing and sucking pests in a given transgenic plant, we generated transgenic tobacco, Arabidopsis, and rice plants expressing the fusion protein, AaIT/GNA, in which an insecticidal scorpion venom neurotoxin (Androctonus australis toxin, AaIT) is fused to snowdrop lectin (Galanthus nivalis agglutinin, GNA). Compared with transgenic tobacco and Arabidopsis plants expressing AaIT or GNA, transgenic plants expressing AaIT/GNA exhibited increased resistance and toxicity to one chewing pest, the cotton bollworm, Helicoverpa armigera. Transgenic tobacco and rice plants expressing AaIT/GNA showed increased resistance and toxicity to two sucking pests, the whitefly, Bemisia tabaci, and the rice brown planthopper, Nilaparvata lugens, respectively. Moreover, in the field, transgenic rice plants expressing AaIT/GNA exhibited a significant improvement in grain yield when infested with N. lugens. This study shows that expressing the AaIT/GNA fusion protein in transgenic plants can be a useful approach for controlling pests, particularly sucking pests which are not susceptible to the toxin in Bt crops. © 2015 Institute of Zoology, Chinese Academy of Sciences.

Overview of seismic resistant design of Indian Nuclear Power Plants

International Nuclear Information System (INIS)

Sharma, G.K.; Hawaldar, R.V.K.P.; Vinod Kumar

2007-01-01

Safe operation of a Nuclear Power Plant (NPP) is of utmost importance. NPPs consist of various Structure, System and Equipment (SS and E) that are designed to resist the forces generated due to a natural phenomenon like earthquake. An earthquake causes severe oscillatory ground motion of short duration. Seismic resistant design of SS and E calls for evaluation of effect of severe ground shaking for assuring the structural integrity and operability during and after the occurrence of earthquake event. Overall exercise is a multi-disciplinary approach. First of standardized 220 MWe design reactor is Narora Atomic Power Station. Seismic design was carried out as per state of art then, for the first time. The twelve 220 MWe reactors and two 540 MWe reactors designed since 1975 have been seismically qualified for the earthquake loads expected in the region. Seismic design of 700 MWe reactor is under advanced stage of finalization. Seismic re-evaluation of six numbers of old plants has been completed as per latest state of art. Over the years, expertise have been developed at Nuclear Power Corporation of India Limited, Bhabha Atomic Research Centre, prominent educational institutes, research laboratories and engineering consultants in the country in the area of seismic design, analysis and shake table testing. (author)

Crown sheath rot of rice: host-range and varietal resistance to Gaeumannomyces graminis var. graminis

Directory of Open Access Journals (Sweden)

Cecília do Nascimento Peixoto

2014-09-01

Full Text Available Several gramineous plants occurring in rice fields show symptoms of crown sheath rot of rice, caused by Gaeumannomyces graminis var. graminis (Ggg, under natural conditions of infection. The pathogenicity of the Ggg-a 01 isolate, collected from rice, was tested on seven grass species and eight cereals, under greenhouse conditions, in order to get information on host-range and resistance of rice genotypes to crown sheath rot. The inoculation tests showed that the rice isolate was pathogenic to weeds such as Echinochloa crusgalli, Pennisetum setosum, Brachiaria sp., Digitaria horizontalis, Brachiaria plantaginea, Eleusine indica and Cenchrus echinatus, and that these species are potential hosts to the pathogen. Winter cereals such as wheat, oat, rye, barley and triticale, as well as sorghum, maize and millet, presented different degrees of susceptibility to the Ggg-a isolate. Significant differences were observed in relation to lesion height and production of hyphopodia and perithecia on culms. Perithecia were not observed on millet, sorghum, southern sandbur and maize. The resistance of 58 upland rice genotypes was tested, and the SCIA16 and SCIA08 genotypes presented lesion height significantly smaller, being considered resistant, when compared to the highly susceptible CNAS10351 genotype.

Isolation of plant growth promoting rhizobacteria of guava plants (Psidium guajava

Directory of Open Access Journals (Sweden)

Blanca Estela Gómez Luna

2012-09-01

Full Text Available Guava production for 2008 in the state of Guanajuato was 177 ha in area planted and the same number of area harvested, production in 1,130.80 Ton. In traditional farming practices have made excessive use of mineral fertilizers, which, if it is true, ensure a good production are expensive and come to cause imbalances in agroecosystems by contamination of soil, water, and food. In this work we evaluated the effect of Bacillus subtilis strains as plant growth promoter rhizobacteria in guava plants under greenhouse conditions. We used three strains were inoculated potted plant with guava. We measured the height, number of branches and leaves. Guava orchards of 2 then display of soil were taken for the isolation andcharacterization of rhizobacteria. Selective medium was used with 1 - carboxylic acid, -1 - aminocyclopropane and selecting bacteria with ACC desaminase activity. For the isolates were determined antibiotic resistance, confrontation with fungal pathogens, plant growth tests in vitro and BIOLOG metabolic profiles. We found 30 isolates with ACC activities, 7 have the effect of biological control and 5 had effect on root development in vitro. The use of growth promotingrhizobacteria are an excellent alternative for improving the production of guavas, growing very little is known of themicroflora associated with the rhizosphere and the ecological role they have in the ground.

The Applications to Increase Drought Tolerance of Plants

Directory of Open Access Journals (Sweden)

İlkay Yavaş

2016-01-01

Full Text Available Terminal drought is a major threat that adversely affects crop growth and metabolism, and limits the yield. Water stress causes many morphological, physiological and biochemical changes in plants. Plant height, root length, leaf area, fresh and dry biomass are reduced under drought stress. Besides, water stress causes the reduction of relative water content, the closure of stomata and decrease in photosynthesis and chlorophyll content. Antioxidant enzymes such as glutathione reductase (GR, superoxide dismutase (SOD, peroxidase (POD, ascorbat peroxidase (ASC, glutatiton (GSH, catalase (CAT enzyme activities, the indicator of oxidative stress malondialdehyde (MDA and proline levels also changes in drought conditions. Nutrient uptake by plants is prevented or restricted before grain development stage during drought conditions. Therefore the application of plant nutrients followed by micronutrient remobilization within plant is great importance. Osmoprotectants (cytokinin, mannitol, abscisic acid, proline, glycine betaine, polyamine etc. detoxify adverse effect of reactive oxygen species (ROS and alleviate drought stress. Exogenous plant growth promoting rhizobacteria (PGPR application encourage plant growth by colonizing the plant root and increase plants’ resistance to water stress. Besides, the farmers can use conservation tillage system in dry periods.

Contrasting effects of ethylene biosynthesis on induced plant resistance against a chewing and a piercing-sucking herbivore in rice.

Science.gov (United States)

Lu, Jing; Li, Jiancai; Ju, Hongping; Liu, Xiaoli; Erb, Matthias; Wang, Xia; Lou, Yonggen

2014-11-01

Ethylene is a stress hormone with contrasting effects on herbivore resistance. However, it remains unknown whether these differences are plant- or herbivore-specific. We cloned a rice 1-aminocyclopropane-1-carboxylic acid (ACC) synthase gene, OsACS2, whose transcripts were rapidly up-regulated in response to mechanical wounding and infestation by two important pests: the striped stem borer (SSB) Chilo suppressalis and the brown planthopper (BPH) Nilaparvata lugens. Antisense expression of OsACS2 (as-acs) reduced elicited ethylene emission, SSB-elicited trypsin protease inhibitor (TrypPI) activity, SSB-induced volatile release, and SSB resistance. Exogenous application of ACC restored TrypPI activity and SSB resistance. In contrast to SSB, BPH infestation increased volatile emission in as-acs lines. Accordingly, BPH preferred to feed and oviposit on wild-type (WT) plants--an effect that could be attributed to two repellent volatiles, 2-heptanone and 2-heptanol, that were emitted in higher amounts by as-acs plants. BPH honeydew excretion was reduced and natural enemy attraction was enhanced in as-acs lines, resulting in higher overall resistance to BPH. These results demonstrate that ethylene signaling has contrasting, herbivore-specific effects on rice defense responses and resistance against a chewing and a piercing-sucking insect, and may mediate resistance trade-offs between herbivores of different feeding guilds in rice. © The Author 2014. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.

Arsenic transformation and plant growth promotion characteristics of As-resistant endophytic bacteria from As-hyperaccumulator Pteris vittata.

Science.gov (United States)

Xu, Jia-Yi; Han, Yong-He; Chen, Yanshan; Zhu, Ling-Jia; Ma, Lena Q

2016-02-01

The ability of As-resistant endophytic bacteria in As transformation and plant growth promotion was determined. The endophytes were isolated from As-hyperaccumulator Pteris vittata (PV) after growing for 60 d in a soil containing 200 mg kg(-1) arsenate (AsV). They were isolated in presence of 10 mM AsV from PV roots, stems, and leaflets, representing 4 phyla and 17 genera. All endophytes showed at least one plant growth promoting characteristics including IAA synthesis, siderophore production and P solubilization. The root endophytes had higher P solubilization ability than the leaflet (60.0 vs. 18.3 mg L(-1)). In presence of 10 mM AsV, 6 endophytes had greater growth than the control, suggesting As-stimulated growth. Furthermore, root endophytes were more resistant to AsV while the leaflet endophytes were more tolerant to arsenite (AsIII), which corresponded to the dominant As species in PV tissues. Bacterial As resistance was positively correlated to their ability in AsV reduction but not AsIII oxidation. The roles of those endophytes in promoting plant growth and As resistance in P. vittata warrant further investigation. Published by Elsevier Ltd.

Connecting elements for wind power plants with an enhanced vibration resistance; Verbindungselemente fuer Windenergieanlagen mit erhoehter Schwingfestigkeit

Energy Technology Data Exchange (ETDEWEB)

Hasselmann, Uwe; Braun, Tobias [Peiner Umformtechnik GmbH, Peine (Germany)

2010-07-01

In wind power plants, large quantities of screws with large dimensions are used. This concerns to steel construction screws according to the regulations DIN EN 14399-4 or DASt 021. These screws are hot-galvanized. The wind power plants are exposed to large stochastic oscillation loads. Therefore, there exist fatigue proof procedures which follow a regulation from the construction sector (DIN EN 1993-1-9) and still are continued to specify in a certification guideline of the Germanic Lloyd. Within the range of mechanical engineering of wind power plants, a strength verification of the screwed joints follows the VDI regulation 2230. The vibration resistance of the screw is an input for the proof of vibration resistance. During the production of screws with an enhanced vibration resistance in the hot-galvanized condition one may dispense with the reducing coefficients for hot-galvanizing due to the technical measures. The use of connecting elements with enhanced vibration resistance enables the dimensioning of ring flange joints with less or smaller screws. This economically can be of advantage, since this positively affects the dimensions of the flange. In the borderline case with enhanced swinging loads the computational proof is enabled yet.

Effect of silicon and acibenzolar-s-methyl on colored cotton plants infested or not with Aphis gossypii Glover (Hemiptera, Aphididae

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Eliana Alcantra

2011-06-01

Full Text Available Effect of silicon and acibenzolar-s-methyl on colored cotton plants infested or not with Aphis gossypii Glover (Hemiptera, Aphididae. The aphid Aphis gossypii is an insect pest that causes damage mainly at the beginning of the cotton plant development. The effect of resistance inductors silicon and acibenzolar-s-methyl (ASM on the development of colored cotton plants were researched in the presence and absence of A. gossypii. Three colored cotton cultivars were sown in pots and individually infested with 25 apterous aphids, 13 days after the application of the inductors. Fifteen days after plant emergence, the silicon was applied at a dosage equivalent to 3 t/ha and acibenzolar-s-methyl in 0.2% solution of the product BION 500®. After 21 days of infestation the following parameters were evaluated: plant height, stem diameter, dry matter of aerial part and root, and total number of aphids replaced. It was verified that the plant height was reduced in the presence of aphids and all variables were negatively affected by the application of ASM. However, silicon did not affect plant development.

Fatty acid profiles from the plasma membrane and detergent resistant membranes of two plant species.

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Carmona-Salazar, Laura; El Hafidi, Mohammed; Gutiérrez-Nájera, Nora; Noyola-Martínez, Liliana; González-Solís, Ariadna; Gavilanes-Ruíz, Marina

2015-01-01

It is essential to establish the composition of the plant plasma membrane in order to understand its organization and behavior under continually changing environments. Knowledge of the lipid phase, in particular the fatty acid (FA) complex repertoire, is important since FAs determine many of the physical-chemical membrane properties. FAs are constituents of the membrane glycerolipid and sphingolipid backbones and can also be linked to some sterols. In addition, FAs are components of complex lipids that can constitute membrane micro-domains, and the use of detergent-resistant membranes is a common approach to study their composition. The diversity and cellular allocation of the membrane lipids containing FAs are very diverse and the approaches to analyze them provide only general information. In this work, a detailed FA analysis was performed using highly purified plasma membranes from bean leaves and germinating maize embryos and their respective detergent-resistant membrane preparations. The analyses showed the presence of a significant amount of very long chain FAs (containing 28C, 30C and 32C), in both plasma membrane preparations from bean and maize, that have not been previously reported. Herein is demonstrated that a significant enrichment of very long chain saturated FAs and saturated FAs can occur in detergent-resistant membrane preparations, as compared to the plasma membranes from both plant species. Considering that a thorough analysis of FAs is rarely performed in purified plasma membranes and detergent-resistant membranes, this work provides qualitative and quantitative evidence on the contributions of the length and saturation of FAs to the organization of the plant plasma membrane and detergent-resistant membranes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Scale-Dependent Assessment of Relative Disease Resistance to Plant Pathogens

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Peter Skelsey

2014-03-01

Full Text Available Phenotyping trials may not take into account sufficient spatial context to infer quantitative disease resistance of recommended varieties in commercial production settings. Recent ecological theory—the dispersal scaling hypothesis—provides evidence that host heterogeneity and scale of host heterogeneity interact in a predictable and straightforward manner to produce a unimodal (“humpbacked” distribution of epidemic outcomes. This suggests that the intrinsic artificiality (scale and design of experimental set-ups may lead to spurious conclusions regarding the resistance of selected elite cultivars, due to the failure of experimental efforts to accurately represent disease pressure in real agricultural situations. In this model-based study we investigate the interaction of host heterogeneity and scale as a confounding factor in the inference from ex-situ assessment of quantitative disease resistance to commercial production settings. We use standard modelling approaches in plant disease epidemiology and a number of different agronomic scenarios. Model results revealed that the interaction of heterogeneity and scale is a determinant of relative varietal performance under epidemic conditions. This is a previously unreported phenomenon that could provide a new basis for informing the design of future phenotyping platforms, and optimising the scale at which quantitative disease resistance is assessed.

Love and fear of heights: the pathophysiology and psychology of height imbalance.

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Salassa, John R; Zapala, David A

2009-01-01

Individual psychological responses to heights vary on a continuum from acrophobia to height intolerance, height tolerance, and height enjoyment. This paper reviews the English literature and summarizes the physiologic and psychological factors that generate different responses to heights while standing still in a static or motionless environment. Perceptual cues to height arise from vision. Normal postural sway of 2 cm for peripheral objects within 3 m increases as eye-object distance increases. Postural sway >10 cm can result in a fall. A minimum of 20 minutes of peripheral retinal arc is required to detect motion. Trigonometry dictates that a 20-minute peripheral retinal arch can no longer be achieved in a standing position at an eye-object distance of >20 m. At this distance, visual cues conflict with somatosensory and vestibular inputs, resulting in variable degrees of imbalance. Co-occurring deficits in the visual, vestibular, and somatosensory systems can significantly increase height imbalance. An individual's psychological makeup, influenced by learned and genetic factors, can influence reactions to height imbalance. Enhancing peripheral vision and vestibular, proprioceptive, and haptic functions may improve height imbalance. Psychotherapy may improve the troubling subjective sensations to heights.

A Simple and Sensitive Plant-Based Western Corn Rootworm Bioassay Method for Resistance Determination and Event Selection.

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Wen, Zhimou; Chen, Jeng Shong

2018-05-26

We report here a simple and sensitive plant-based western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), bioassay method that allows for examination of multiple parameters for both plants and insects in a single experimental setup within a short duration. For plants, injury to roots can be visually examined, fresh root weight can be measured, and expression of trait protein in plant roots can be analyzed. For insects, in addition to survival, larval growth and development can be evaluated in several aspects including body weight gain, body length, and head capsule width. We demonstrated using the method that eCry3.1Ab-expressing 5307 corn was very effective against western corn rootworm by eliciting high mortality and significantly inhibiting larval growth and development. We also validated that the method allowed determination of resistance in an eCry3.1Ab-resistant western corn rootworm strain. While data presented in this paper demonstrate the usefulness of the method for selection of events of protein traits and for determination of resistance in laboratory populations, we envision that the method can be applied in much broader applications.

Comparative Effectiveness of Potential Elicitors of Plant Resistance against Spodoptera frugiperda (J. E. Smith (Lepidoptera: Noctuidae in Four Crop Plants.

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John W Gordy

Full Text Available Feeding by insect herbivores activates plant signaling pathways, resulting in the enhanced production of secondary metabolites and other resistance-related traits by injured plants. These traits can reduce insect fitness, deter feeding, and attract beneficial insects. Organic and inorganic chemicals applied as a foliar spray, seed treatment, or soil drench can activate these plant responses. Azelaic acid (AA, benzothiadiazole (BTH, gibberellic acid (GA, harpin, and jasmonic acid (JA are thought to directly mediate plant responses to pathogens and herbivores or to mimic compounds that do. The effects of these potential elicitors on the induction of plant defenses were determined by measuring the weight gains of fall armyworm, Spodoptera frugiperda (J. E. Smith (FAW (Lepidoptera: Noctuidae larvae on four crop plants, cotton, corn, rice, and soybean, treated with the compounds under greenhouse conditions. Treatment with JA consistently reduced growth of FAW reared on treated cotton and soybean. In contrast, FAW fed BTH- and harpin-treated cotton and soybean tissue gained more weight than those fed control leaf tissue, consistent with negative crosstalk between the salicylic acid and JA signaling pathways. No induction or inconsistent induction of resistance was observed in corn and rice. Follow-up experiments showed that the co-application of adjuvants with JA failed to increase the effectiveness of induction by JA and that soybean looper [Chrysodeixis includens (Walker], a relative specialist on legumes, was less affected by JA-induced responses in soybean than was the polyphagous FAW. Overall, the results of these experiments demonstrate that the effectiveness of elicitors as a management tactic will depend strongly on the identities of the crop, the pest, and the elicitor involved.

Comparative Effectiveness of Potential Elicitors of Plant Resistance against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in Four Crop Plants.

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Gordy, John W; Leonard, B Rogers; Blouin, David; Davis, Jeffrey A; Stout, Michael J

2015-01-01

Feeding by insect herbivores activates plant signaling pathways, resulting in the enhanced production of secondary metabolites and other resistance-related traits by injured plants. These traits can reduce insect fitness, deter feeding, and attract beneficial insects. Organic and inorganic chemicals applied as a foliar spray, seed treatment, or soil drench can activate these plant responses. Azelaic acid (AA), benzothiadiazole (BTH), gibberellic acid (GA), harpin, and jasmonic acid (JA) are thought to directly mediate plant responses to pathogens and herbivores or to mimic compounds that do. The effects of these potential elicitors on the induction of plant defenses were determined by measuring the weight gains of fall armyworm, Spodoptera frugiperda (J. E. Smith) (FAW) (Lepidoptera: Noctuidae) larvae on four crop plants, cotton, corn, rice, and soybean, treated with the compounds under greenhouse conditions. Treatment with JA consistently reduced growth of FAW reared on treated cotton and soybean. In contrast, FAW fed BTH- and harpin-treated cotton and soybean tissue gained more weight than those fed control leaf tissue, consistent with negative crosstalk between the salicylic acid and JA signaling pathways. No induction or inconsistent induction of resistance was observed in corn and rice. Follow-up experiments showed that the co-application of adjuvants with JA failed to increase the effectiveness of induction by JA and that soybean looper [Chrysodeixis includens (Walker)], a relative specialist on legumes, was less affected by JA-induced responses in soybean than was the polyphagous FAW. Overall, the results of these experiments demonstrate that the effectiveness of elicitors as a management tactic will depend strongly on the identities of the crop, the pest, and the elicitor involved.

Activation of Pathogenesis-related Genes by the Rhizobacterium, Bacillus sp. JS, Which Induces Systemic Resistance in Tobacco Plants.

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Kim, Ji-Seong; Lee, Jeongeun; Lee, Chan-Hui; Woo, Su Young; Kang, Hoduck; Seo, Sang-Gyu; Kim, Sun-Hyung

2015-06-01

Plant growth promoting rhizobacteria (PGPR) are known to confer disease resistance to plants. Bacillus sp. JS demonstrated antifungal activities against five fungal pathogens in in vitro assays. To verify whether the volatiles of Bacillus sp. JS confer disease resistance, tobacco leaves pre-treated with the volatiles were damaged by the fungal pathogen, Rhizoctonia solani and oomycete Phytophthora nicotianae. Pre-treated tobacco leaves had smaller lesion than the control plant leaves. In pathogenesis-related (PR) gene expression analysis, volatiles of Bacillus sp. JS caused the up-regulation of PR-2 encoding β-1,3-glucanase and acidic PR-3 encoding chitinase. Expression of acidic PR-4 encoding chitinase and acidic PR-9 encoding peroxidase increased gradually after exposure of the volatiles to Bacillus sp. JS. Basic PR-14 encoding lipid transfer protein was also increased. However, PR-1 genes, as markers of salicylic acid (SA) induced resistance, were not expressed. These results suggested that the volatiles of Bacillus sp. JS confer disease resistance against fungal and oomycete pathogens through PR genes expression.

Creation of variation in Basella for rust resistance through mutagenesis

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Makambila, C [Phytopathology Lab., Faculty of Sciences, Brazzaville (Congo)

1997-07-01

African spinach, basella is grown as a leafy vegetable in Central Africa. Basella cultivars belong to the species Basella alba and B. rubra which are seed propagated and are likely Asiatic in origin. Basella alba seeds were irradiated with doses of 50, 100, 200, 300 and 500 Gy to create variation for rust resistance which is caused by the fungus, Uromyces basellae Sidow. The effects of irradiation were investigated on seed germination, plant mortality and height. Seed germination varied from 97% for those irradiated with 50 Gy to 39% with 500 Gy, and LD{sub 50} for seed germination was between 300 to 400 Gy. Doses between 50 and 150 Gy did not cause any mortality of plants obtained from irradiated seeds; however, doses between 200 to 500 Gy caused high mortality among such plants. Irradiation with 150 Gy inhibited plant growth by 48% in relation to the growth of control plants. Based on the results, radiation doses above 150 and up to 400 Gy were used for the production of desired variation. (author). 11 refs, 9 figs.

Creation of variation in Basella for rust resistance through mutagenesis

International Nuclear Information System (INIS)

Makambila, C.

1997-01-01

African spinach, basella is grown as a leafy vegetable in Central Africa. Basella cultivars belong to the species Basella alba and B. rubra which are seed propagated and are likely Asiatic in origin. Basella alba seeds were irradiated with doses of 50, 100, 200, 300 and 500 Gy to create variation for rust resistance which is caused by the fungus, Uromyces basellae Sidow. The effects of irradiation were investigated on seed germination, plant mortality and height. Seed germination varied from 97% for those irradiated with 50 Gy to 39% with 500 Gy, and LD 50 for seed germination was between 300 to 400 Gy. Doses between 50 and 150 Gy did not cause any mortality of plants obtained from irradiated seeds; however, doses between 200 to 500 Gy caused high mortality among such plants. Irradiation with 150 Gy inhibited plant growth by 48% in relation to the growth of control plants. Based on the results, radiation doses above 150 and up to 400 Gy were used for the production of desired variation. (author). 11 refs, 9 figs

Silicon treatment to rice (oryza sativa l. cv 'gopumbyeo') plants during different growth periods and its effects on growth and grain yield

International Nuclear Information System (INIS)

Kim, Y.H.; Waqas, M.; Kamran, M.

2012-01-01

Silicon (Si) has been considered a beneficial element for plant growth. We have assessed the effects of Si application on rice (Oryza sativa L.) growth and its grain yield at field level. For this, we performed two experiments. In experiment 1, we applied Si of three different concentrations (liquid Si-10, 25 and 36%) to the seedbed of rice before transplantation into paddy field. The results of this experiment showed that Si application to rice seedbeds did not affected the rice plant height and shoot fresh weight but its application significantly increased the pushing resistance of rice plants from 12.2-16.7% as compared with water applied control plants. The lodging index of Si treated rice plants significantly decreased (13.7% on LS-25) as compared with control. Similarly, Si treated plants had significantly higher yield. Upon Si treatment (LS-36), the grain yield per 10 acre and panicles per plant were 15.1% and 6. 3% higher than the water treated control plants respectively. The best concentration (LS-36%) revealed in the first experiment was foliar applied at 10 days before heading stage, initial tilling stage and panicle initiation stage to the rice leaves and we observed that shoot biomass was not significantly different between control and Si treated plants. However, significantly higher pushing resistance (10.5%-13.8%) and plant height (12.2%-16.7%) were observed while lower lodging index (7.6-7.8%) was recorded for Si treated plants as compared to control plants. Similarly, Si application increased the number of panicles per plant as well as the grain yield per 10 acre as compared to control. In conclusion, the Si application can significantly regulate plant growth and yield if applied at proper time with feasible concentration. (author)

Mono- and Digalactosyldiacylglycerol Lipids Function Nonredundantly to Regulate Systemic Acquired Resistance in Plants

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Qing-ming Gao

2014-12-01

Full Text Available Summary: The plant galactolipids monogalactosyldiacylglycerol (MGDG and digalactosyldiacylglycerol (DGDG have been linked to the anti-inflammatory and cancer benefits of a green leafy vegetable diet in humans due to their ability to regulate the levels of free radicals like nitric oxide (NO. Here, we show that DGDG contributes to plant NO as well as salicylic acid biosynthesis and is required for the induction of systemic acquired resistance (SAR. In contrast, MGDG regulates the biosynthesis of the SAR signals azelaic acid (AzA and glycerol-3-phosphate (G3P that function downstream of NO. Interestingly, DGDG is also required for AzA-induced SAR, but MGDG is not. Notably, transgenic expression of a bacterial glucosyltransferase is unable to restore SAR in dgd1 plants even though it does rescue their morphological and fatty acid phenotypes. These results suggest that MGDG and DGDG are required at distinct steps and function exclusively in their individual roles during the induction of SAR. : The galactolipids monogalactosyldiacylglycerol (MGDG and digalactosyldiacylglycerol (DGDG constitute ∼80% of total membrane lipids in plants. Gao et al. now show that these galactolipids function nonredundantly to regulate systemic acquired resistance (SAR. Furthermore, they show that the terminal galactose on the α-galactose-β-galactose head group of DGDG is critical for SAR.

Effects of plant phenology and vertical height on accuracy of radio-telemetry locations

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Grovenburg, Troy W.; Jacques, Christopher N.; Klaver, Robert W.; DePerno, Christopher S.; Lehman, Chad P.; Brinkman, Todd J.; Robling, Kevin A.; Rupp, Susan P.; Jenks, Jonathan A.

2013-01-01

The use of very high frequency (VHF) radio-telemetry remains wide-spread in studies of wildlife ecology and management. However, few studies have evaluated the influence of vegetative obstruction on accuracy in differing habitats with varying transmitter types and heights. Using adult and fawn collars at varying heights above the ground (0, 33, 66 and 100 cm) to simulate activities (bedded, feeding and standing) and ages (neonate, juvenile and adult) of deer Odocoileus spp., we collected 5,767 bearings and estimated 1,424 locations (28-30 for each of 48 subsamples) in three habitat types (pasture, grassland and forest), during two stages of vegetative growth (spring and late summer). Bearing error was approximately twice as large at a distance of 900 m for fawn (9.9°) than for adult deer collars (4.9°). Of 12 models developed to explain the variation in location error, the analysis of covariance model (HT*D + C*D + HT*TBA + C*TBA) containing interactions of height of collar above ground (HT), collar type (C), vertical height of understory vegetation (D) and tree basal area (TBA) was the best model (wi = 0.92) and explained ∼ 71% of the variation in location error. Location error was greater for both collar types at 0 and 33 cm above the ground compared to 66 and 100 cm above the ground; however, location error was less for adult than fawn collars. Vegetation metrics influenced location error, which increased with greater vertical height of understory vegetation and tree basal area. Further, interaction of vegetation metrics and categorical variables indicated significant effects on location error. Our results indicate that researchers need to consider study objectives, life history of the study animal, signal strength of collar (collar type), distance from transmitter to receiver, topographical changes in elevation, habitat composition and season when designing telemetry protocols. Bearing distances in forested habitat should be decreased (approximately 23

Antibacterial activities of medicinal plants against multidrug resistant urinary tract pathogens

International Nuclear Information System (INIS)

Aziz, M.A.; Adnan, M.; Rahman, H.; Allah, A.; Hashem, A.

2017-01-01

Urinary tract infections (UTI) caused by multi-drug resistant (MDR) bacterial pathogens have become a serious global health concern. Main etiological agents for UTI are Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa. Recently, medicinal plants have found great popularity in medical treatment for different kinds of infections including urinary tract infections. The study has been planned to evaluate the efficacy of alkaloids, flavonoids, saponins and crude extracts of medicinal plants i.e. Syzygium aromaticum, Glycerrhiza glabra,Laurus nobilis and Brassica rapa against MDR urinary tract pathogens through agar well diffusion method. To investigate the Minimum Inhibitory Concentrations (MICs) and Minimum Bactericidal Concentration (MBCs), dilution method was used. Quantitative evaluations of phytochemicals indicated the presence of alkaloids in higher concentrations. Results obtained for the antibacterial activities, the crude extracts of the four plants showed significantly higher inhibition zones as compared to other phytochemicals. The MIC values obtained for different extracts varying from 7.5-15 mg/ml. Comparig the activities of the extracts of the the four medicinal plants it was found that Syzygium aromaticum was the most potent plant against the tested bacterial pathogens indicating its strong candidateship for the drug development. (author)

Mercuric ion reduction and resistance in transgenic Arabidopsis thaliana plants expressing a modified bacterial merA gene.

Science.gov (United States)

Rugh, C L; Wilde, H D; Stack, N M; Thompson, D M; Summers, A O; Meagher, R B

1996-01-01

With global heavy metal contamination increasing, plants that can process heavy metals might provide efficient and ecologically sound approaches to sequestration and removal. Mercuric ion reductase, MerA, converts toxic Hg2+ to the less toxic, relatively inert metallic mercury (Hg0) The bacterial merA sequence is rich in CpG dinucleotides and has a highly skewed codon usage, both of which are particularly unfavorable to efficient expression in plants. We constructed a mutagenized merA sequence, merApe9, modifying the flanking region and 9% of the coding region and placing this sequence under control of plant regulatory elements. Transgenic Arabidopsis thaliana seeds expressing merApe9 germinated, and these seedlings grew, flowered, and set seed on medium containing HgCl2 concentrations of 25-100 microM (5-20 ppm), levels toxic to several controls. Transgenic merApe9 seedlings evolved considerable amounts of Hg0 relative to control plants. The rate of mercury evolution and the level of resistance were proportional to the steady-state mRNA level, confirming that resistance was due to expression of the MerApe9 enzyme. Plants and bacteria expressing merApe9 were also resistant to toxic levels of Au3+. These and other data suggest that there are potentially viable molecular genetic approaches to the phytoremediation of metal ion pollution. Images Fig. 2 Fig. 3 Fig. 4 PMID:8622910

Arsenic-resistant and plant growth-promoting Firmicutes and γ-Proteobacteria species from industrially polluted irrigation water and corresponding cropland.

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Qamar, N; Rehman, Y; Hasnain, S

2017-09-01

The aim of the study was to explore irrigation water polluted with industrial waste and corresponding cropland to screen bacteria for As detoxification and plant growth promotion. Plant growth-promoting (PGP) As-resistant cropland bacteria were isolated from contaminated irrigation water and corresponding agricultural soil. Phylogenetic analysis revealed that the isolates belonged to two distinct bacterial lineages; Firmicutes and γ-Proteobacteria. Maximum As(V) resistance was exhibited by Klebsiella pneumoniae T22 and Klebsiella oxytoca N53 (550 mmol l -1 ), whereas maximum resistance against As(III) was exhibited by K. oxytoca N53 (200 mmol l -1 ). Maximum As(V) reduction was shown by K. pneumoniae T22 (6·7 mmol l -1 ), whereas maximum As(III) oxidation was exhibited by Bacillus subtilis T23 (4·8 mmol l -1 ). As resistance genes arsB and ACR3 were detected in many of the isolates through polymerase chain reaction. Many of these isolates exhibited PGP traits such as hydrogen cyanide and auxin production as well as phosphate solubilization. The bacterial strains were able to enhance Triticum aestivum growth both in the absence and presence of As, and statistically significant increase in shoot and root lengths was observed especially in case of Acinetobacter lwoffii T24 and Citrobacter freundii N52-treated plants. Cropland bacteria have the ability to support plant growth. Bacteria of croplands irrigated with industrially polluted water develop resistance against toxicants. These bacteria are helpful for the plant growth in such contaminated lands. The bacteria capable of both As detoxification and plant growth promotion, such as A. lwoffii T24 and C. freundii N52, are ideal for remediation and reclamation of polluted lands for agriculture purposes. © 2017 The Society for Applied Microbiology.

Ectopic accumulation of linalool confers resistance to Xanthomonas citri subsp. citri in transgenic sweet orange plants.

Science.gov (United States)

Shimada, Takehiko; Endo, Tomoko; Rodríguez, Ana; Fujii, Hiroshi; Goto, Shingo; Matsuura, Takakazu; Hojo, Yuko; Ikeda, Yoko; Mori, Izumi C; Fujikawa, Takashi; Peña, Leandro; Omura, Mitsuo

2017-05-01

In order to clarify whether high linalool content in citrus leaves alone induces strong field resistance to citrus canker caused by Xanthomonas citri subsp. citri (Xcc), and to assess whether this trait can be transferred to a citrus type highly sensitive to the bacterium, transgenic 'Hamlin' sweet orange (Citrus sinensis L. Osbeck) plants over-expressing a linalool synthase gene (CuSTS3-1) were generated. Transgenic lines (LIL) with the highest linalool content showed strong resistance to citrus canker when spray inoculated with the bacterium. In LIL plants inoculated by wounding (multiple-needle inoculation), the linalool level was correlated with the repression of the bacterial titer and up-regulation of defense-related genes. The exogenous application of salicylic acid, methyl jasmonate or linalool triggered responses similar to those constitutively induced in LIL plants. The linalool content in Ponkan mandarin leaves was significantly higher than that of leaves from six other representative citrus genotypes with different susceptibilities to Xcc. We propose that linalool-mediated resistance might be unique to citrus tissues accumulating large amounts of volatile organic compounds in oil cells. Linalool might act not only as a direct antibacterial agent, but also as a signal molecule involved in triggering a non-host resistance response against Xcc. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

An evaluation of corrosion resistant alloys by field corrosion test in Japanese refuse incineration plants

International Nuclear Information System (INIS)

Kawahara, Yuuzou; Nakamura, Masanori; Shibuya, Eiichi; Yukawa, Kenichi

1995-01-01

As the first step for development of the corrosion resistant superheater tube materials of 500 C, 100 ata used in high efficient waste-to-energy plants, field corrosion tests of six conventional alloys were carried out at metal temperatures of 450 C and 550 C for 700 and 3,000 hours in four typical Japanese waste incineration plants. The test results indicate that austenitic alloys containing approximately 80 wt% [Cr+Ni] show excellent corrosion resistance. When the corrosive environment is severe, intergranular corrosion of 40∼200 microm depth occurs in stainless steel and high alloyed materials. It is confirmed quantitatively that corrosion behavior is influenced by environmental corrosion factors such as Cl concentration and thickness of deposits on tube surface, metal temperature, and flue gas temperature. The excellent corrosion resistance of high [Cr+Ni+Mo] alloys such as Alloy 625 is explained by the stability of its protective oxide, such that the time dependence of corrosion nearly obeys the parabolic rate law

Evaluation of indicators for the early selection of the height character in Musa spp.

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Lourdes García Rodríguez

2004-10-01

Full Text Available In the plant breeding programs attended by Biotechnology and using the induction of mutations becomes necessary to work with big populations of plants to guarantee bigger possibilities to be successful in the work. For what to have a selection system that allows to carry out the same one in acclimatization phase would allow to shorten the outlines of improvement and to diminish the population’s size notably to evaluate in field phase, what would bear to diminish the expenses in the whole process of studies clones them. With the aim of determining possible morphological indicators that could be used as markers for the selection of low bearing in the clones of the FHIA were studied in conditions of acclimatization different cultivars and banana mutants, being evaluated several morphological characters as: the height of the plant, number of leaves, long and wide of the penultimate emitted leaf, as well as the long of their petiole and the distance between two serial leaves. It was also evaluated the height of the plants under conditions in vitro when they were subcultivate in a culture medium with different concentration of AG3. The results indicate that inside the evaluated morphological characters, those that more early allowed to distinguish among plants of low bearing were: the long of the petiole and the height of the plants and that the moment of the selection should be to the 60 days. Not differences were observed between genotypes when they were subcultivate in the culture medium enriched with AG3. Key words: banana, early selection, low bearing, morphological markers, plantain

Bioaerosol emissions and detection of airborne antibiotic resistance genes from a wastewater treatment plant

Science.gov (United States)

Li, Jing; Zhou, Liantong; Zhang, Xiangyu; Xu, Caijia; Dong, Liming; Yao, Maosheng

2016-01-01

Air samples from twelve sampling sites (including seven intra-plant sites, one upwind site and four downwind sites) from a wastewater treatment plant (WWTP) in Beijing were collected using a Reuter Centrifugal Sampler High Flow (RCS); and their microbial fractions were studied using culturing and high throughput gene sequence. In addition, the viable (fluorescent) bioaerosol concentrations for 7 intra-plant sites were also monitored for 30 min each using an ultraviolet aerodynamic particle sizer (UV-APS). Both air and water samples collected from the plant were investigated for possible bacterial antibiotic resistance genes and integrons using polymerase chain reaction (PCR) coupled with gel electrophoresis. The results showed that the air near sludge thickening basin was detected to have the highest level of culturable bacterial aerosols (up to 1697 CFU/m3) and fungal aerosols (up to 930 CFU/m3). For most sampling sites, fluorescent peaks were observed at around 3-4 μm, except the office building with a peak at 1.5 μm, with a number concentration level up to 1233-6533 Particles/m3. About 300 unique bacterial species, including human opportunistic pathogens, such as Comamonas Testosteroni and Moraxella Osloensis, were detected from the air samples collected over the biological reaction basin. In addition, we have detected the sul2 gene resistant to cotrimoxazole (also known as septra, bactrim and TMP-SMX) and class 1 integrase gene from the air samples collected from the screen room and the biological reaction basin. Overall, the screen room, sludge thickening basin and biological reaction basin imposed significant microbial exposure risks, including those from airborne antibiotic resistance genes.

The Physiological and Biochemical Mechanisms Providing the Increased Constitutive Cold Resistance in the Potato Plants, Expressing the Yeast SUC2 Gene Encoding Apoplastic Invertase

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A.N. Deryabin

2016-05-01

Full Text Available The expression of heterologous genes in plants is an effective method to improve our understanding of plant resistance mechanisms. The purpose of this work was to investigate the involvement of cell-wall invertase and apoplastic sugars into constitutive cold resistance of potato (Solanum tuberosum L., cv. Dйsirйe plants, which expressed the yeast SUC2 gene encoding apoplastic invertase. WT-plants of a potato served as the control. The increase in the essential cell-wall invertase activity in the leaves of transformed plants indicates significant changes in the cellular carbohydrate metabolism and regulatory function of this enzyme. The activity of yeast invertase changed the composition of intracellular sugars in the leaves of the transformed potato plant. The total content of sugars (sucrose, glucose, fructose in the leaves and apoplast was higher in the transformants, in comparison by WT-plants. Our data indicate higher constitutive resistance of transformants to severe hypothermia conditions compared to WT-plants. This fact allows us to consider cell-wall invertase as a enzyme of carbohydrate metabolism playing an important regulatory role in the metabolic signaling upon forming increased plant resistance to low temperature. Thus, the potato line with the integrated SUC2 gene is a convenient tool to study the role of the apoplastic invertase and the products of its activity during growth, development and formation constitutive resistance to hypothermia.

[The differences of the effects of Vrd1 and Ppd-D1 gene alleles on winterhardiness, frost resistance, and yield in winter wheat].

Science.gov (United States)

Mokanu, N V; Faĭt, V I

2008-01-01

The influence of allelic differences of Vrd1 and Ppd-D1 genes on winterhardiness, frost resistance, yield and its components was studied in recombinant-inbred F5 lines of Odesskaya 16/Bezostaya 1. From 9 to 15% differences in the resistance of recombinant-inbred lines were determined by alternative alleles of Vrd1 gene and 10-16% of Ppd-D1 gene. Interaction of vrd1 and Ppd-D1a alleles led to the higher winterhardiness and frost resistance of tillered plants during the winter. At the same time the significant increase of the period to heading, plant height and the tendency of yield reduction were revealed for vrd1 vrd1 Ppd-D1a Ppd-D1a lines when compared to the lines of Vrd1 Vrd1 Ppd-D1a Ppd-D1a genotype.

FY 2000 report on the survey on energy conservation technology of large plant using ultra high corrosion resistant materials; 2000 nendo chokotaishokusei zairyo wo mochiita ogata plant no sho energy gijutsu ni kansuru chosa hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

For the purpose of achieving remarkable energy conservation/resource conservation in large plants, the paper carried out an investigational survey of effects obtained in case of applying amorphous super metal which is the newest corrosion resistant material. Amorphous alloys as an ultra high corrosion resistant material are a peculiar material which shows the extremely excellent corrosion resistance even in much strong acid by containing passivated elements with the needed concentration. The corrosion resistant amorphous alloy applied to large plants need the thickness and diameter of more than several millimeters as a bulk material. The subjects are scaling-up of bulk materials and stabilization of characteristics. Even under the tough dew point corrosion environment of the waste power plant, etc., heat recovery from exhaust gas is made possible by heat exchanger applied with ultra high corrosion resistant materials. Effects of the annual heat recovery from the nationwide refuse incinerators and coal thermal power plants are estimated to be approximately 5.2 million kL toe, that is, to be equal to energy conservation of 6 x a million kW class power plant. (NEDO)

The relationship between tree height and leaf area: sapwood area ratio.

Science.gov (United States)

McDowell, N; Barnard, H; Bond, B; Hinckley, T; Hubbard, R; Ishii, H; Köstner, B; Magnani, F; Marshall, J; Meinzer, F; Phillips, N; Ryan, M; Whitehead, D

2002-06-01

The leaf area to sapwood area ratio (A l :A s ) of trees has been hypothesized to decrease as trees become older and taller. Theory suggests that A l :A s must decrease to maintain leaf-specific hydraulic sufficiency as path length, gravity, and tortuosity constrain whole-plant hydraulic conductance. We tested the hypothesis that A l :A s declines with tree height. Whole-tree A l :A s was measured on 15 individuals of Douglas-fir (Pseudotsuga menziesii var. menziesii) ranging in height from 13 to 62 m (aged 20-450 years). A l :A s declined substantially as height increased (P=0.02). Our test of the hypothesis that A l :A s declines with tree height was extended using a combination of original and published data on nine species across a range of maximum heights and climates. Meta-analysis of 13 whole-tree studies revealed a consistent and significant reduction in A l :A s with increasing height (P<0.05). However, two species (Picea abies and Abies balsamea) exhibited an increase in A l :A s with height, although the reason for this is not clear. The slope of the relationship between A l :A s and tree height (ΔA l :A s /Δh) was unrelated to mean annual precipitation. Maximum potential height was positively correlated with ΔA l :A s /Δh. The decrease in A l :A s with increasing tree size that we observed in the majority of species may be a homeostatic mechanism that partially compensates for decreased hydraulic conductance as trees grow in height.

Field Trial and Molecular Characterization of RNAi-Transgenic Tomato Plants That Exhibit Resistance to Tomato Yellow Leaf Curl Geminivirus.

Science.gov (United States)

Fuentes, Alejandro; Carlos, Natacha; Ruiz, Yoslaine; Callard, Danay; Sánchez, Yadira; Ochagavía, María Elena; Seguin, Jonathan; Malpica-López, Nachelli; Hohn, Thomas; Lecca, Maria Rita; Pérez, Rosabel; Doreste, Vivian; Rehrauer, Hubert; Farinelli, Laurent; Pujol, Merardo; Pooggin, Mikhail M

2016-03-01

RNA interference (RNAi) is a widely used approach to generate virus-resistant transgenic crops. However, issues of agricultural importance like the long-term durability of RNAi-mediated resistance under field conditions and the potential side effects provoked in the plant by the stable RNAi expression remain poorly investigated. Here, we performed field trials and molecular characterization studies of two homozygous transgenic tomato lines, with different selection markers, expressing an intron-hairpin RNA cognate to the Tomato yellow leaf curl virus (TYLCV) C1 gene. The tested F6 and F4 progenies of the respective kanamycin- and basta-resistant plants exhibited unchanged field resistance to TYLCV and stably expressed the transgene-derived short interfering RNA (siRNAs) to represent 6 to 8% of the total plant small RNAs. This value outnumbered the average percentage of viral siRNAs in the nontransformed plants exposed to TYLCV-infested whiteflies. As a result of the RNAi transgene expression, a common set of up- and downregulated genes was revealed in the transcriptome profile of the plants selected from either of the two transgenic events. A previously unidentified geminivirus causing no symptoms of viral disease was detected in some of the transgenic plants. The novel virus acquired V1 and V2 genes from TYLCV and C1, C2, C3, and C4 genes from a distantly related geminivirus and, thereby, it could evade the repressive sequence-specific action of transgene-derived siRNAs. Our findings shed light on the mechanisms of siRNA-directed antiviral silencing in transgenic plants and highlight the applicability limitations of this technology as it may alter the transcriptional pattern of nontarget genes.

Application of hordothionins and cecropin B for engineering bacterial disease resistance into plants

NARCIS (Netherlands)

Florack, D.

1994-01-01

Bacterial diseases can cause a drastic decrease of yield in certain crops. Breeding for bacterial disease resistance therefore is of utmost necessity. Up to now, traditional plant breeding was the only method to reach this goal. Recent developments in genetic engineering technology however

Tomato progeny inherit resistance to the nematode Meloidogyne javanica linked to plant growth induced by the biocontrol fungus Trichoderma atroviride.

Science.gov (United States)

Medeiros, Hugo Agripino de; Araújo Filho, Jerônimo Vieira de; Freitas, Leandro Grassi de; Castillo, Pablo; Rubio, María Belén; Hermosa, Rosa; Monte, Enrique

2017-01-10

Root-knot nematodes (RKN) are major crop pathogens worldwide. Trichoderma genus fungi are recognized biocontrol agents and a direct activity of Trichoderma atroviride (Ta) against the RKN Meloidogyne javanica (Mj), in terms of 42% reduction of number of galls (NG), 60% of number of egg masses and 90% of number of adult nematodes inside the roots, has been observed in tomato grown under greenhouse conditions. An in vivo split-root designed experiment served to demonstrate that Ta induces systemic resistance towards Mj, without the need for the organisms to be in direct contact, and significantly reduces NG (20%) and adult nematodes inside tomato roots (87%). The first generation (F1) of Ta-primed tomato plants inherited resistance to RKN; although, the induction of defenses occurred through different mechanisms, and in varying degrees, depending on the Ta-Mj interaction. Plant growth promotion induced by Ta was inherited without compromising the level of resistance to Mj, as the progeny of Ta-primed plants displayed increased size and resistance to Mj without fitness costs. Gene expression results from the defense inductions in the offspring of Ta-primed plants, suggested that an auxin-induced reactive oxygen species production promoted by Ta may act as a major defense strategy during plant growth.

Antibiotic-resistant bacteria: prevalence in food and inactivation by food-compatible compounds and plant extracts.

Science.gov (United States)

Friedman, Mendel

2015-04-22

Foodborne antibiotic-resistant pathogenic bacteria such as Campylobacter jejuni, Bacillus cereus, Clostridium perfringens, Escherichia coli, Salmonella enterica, Staphylococcus aureus, Vibrio cholerae, and Vibrio parahemolyticus can adversely affect animal and human health, but a better understanding of the factors involved in their pathogenesis is needed. To help meet this need, this overview surveys and interprets much of our current knowledge of antibiotic (multidrug)-resistant bacteria in the food chain and the implications for microbial food safety and animal and human health. Topics covered include the origin and prevalence of resistant bacteria in the food chain (dairy, meat, poultry, seafood, and herbal products, produce, and eggs), their inactivation by different classes of compounds and plant extracts and by the use of chlorine and physicochemical methods (heat, UV light, pulsed electric fields, and high pressure), the synergistic antimicrobial effects of combinations of natural antimicrobials with medicinal antibiotics, and mechanisms of antimicrobial activities and resistant effects. Possible areas for future research are suggested. Plant-derived and other safe natural antimicrobial compounds have the potential to control the prevalence of both susceptible and resistant pathogens in various environments. The collated information and suggested research will hopefully contribute to a better understanding of approaches that could be used to minimize the presence of resistant pathogens in animal feed and human food, thus reducing adverse effects, improving microbial food safety, and helping to prevent or treat animal and human infections.

The effector SPRYSEC-19 of Globodera rostochiensis suppresses CC-NB-LRR-mediated disease resistance in plants.

Science.gov (United States)

Postma, Wiebe J; Slootweg, Erik J; Rehman, Sajid; Finkers-Tomczak, Anna; Tytgat, Tom O G; van Gelderen, Kasper; Lozano-Torres, Jose L; Roosien, Jan; Pomp, Rikus; van Schaik, Casper; Bakker, Jaap; Goverse, Aska; Smant, Geert

2012-10-01

The potato cyst nematode Globodera rostochiensis invades roots of host plants where it transforms cells near the vascular cylinder into a permanent feeding site. The host cell modifications are most likely induced by a complex mixture of proteins in the stylet secretions of the nematodes. Resistance to nematodes conferred by nucleotide-binding-leucine-rich repeat (NB-LRR) proteins usually results in a programmed cell death in and around the feeding site, and is most likely triggered by the recognition of effectors in stylet secretions. However, the actual role of these secretions in the activation and suppression of effector-triggered immunity is largely unknown. Here we demonstrate that the effector SPRYSEC-19 of G. rostochiensis physically associates in planta with the LRR domain of a member of the SW5 resistance gene cluster in tomato (Lycopersicon esculentum). Unexpectedly, this interaction did not trigger defense-related programmed cell death and resistance to G. rostochiensis. By contrast, agroinfiltration assays showed that the coexpression of SPRYSEC-19 in leaves of Nicotiana benthamiana suppresses programmed cell death mediated by several coiled-coil (CC)-NB-LRR immune receptors. Furthermore, SPRYSEC-19 abrogated resistance to Potato virus X mediated by the CC-NB-LRR resistance protein Rx1, and resistance to Verticillium dahliae mediated by an unidentified resistance in potato (Solanum tuberosum). The suppression of cell death and disease resistance did not require a physical association of SPRYSEC-19 and the LRR domains of the CC-NB-LRR resistance proteins. Altogether, our data demonstrated that potato cyst nematodes secrete effectors that enable the suppression of programmed cell death and disease resistance mediated by several CC-NB-LRR proteins in plants.

Geographic variation in resistance to nectar robbing and consequences for pollination.

Science.gov (United States)

Adler, Lynn S; Leege, Lissa M; Irwin, Rebecca E

2016-10-01

Floral evolution is frequently ascribed to selection by pollinators, but may also be shaped by antagonists. However, remarkably few studies have examined geographic mosaics in resistance to floral antagonists or the consequences for other floral interactions. Gelsemium sempervirens experiences frequent nectar robbing in northern Georgia, but rarely in southern Georgia. We conducted common-garden experiments in both locations using genotypes from each region and measured robbing, pollinator attraction, floral attractive and defensive traits, and plant reproduction. Nectar robbing was more than four times higher in the north vs. south, and pollinator visits did not differ between gardens. Across both gardens, northern genotypes were half as likely to be nectar-robbed but received half as many pollinator visits as southern genotypes, suggesting evolution of resistance to robbing at a cost of reduced pollinator attraction. Plant-level traits, such as height and number of flowers, were more closely associated with resistance to robbing than floral size, shape, or chemistry. Northern genotypes had lower female and estimated male reproduction compared to southern genotypes at both locations, which could be due to costs of resistance to nectar robbing, or costs of adaptations to other biotic or abiotic differences between regions. Our study indicates that geographic variation can play a strong role structuring interactions with floral antagonists and mutualists and provides evidence consistent with the hypothesis that local resistance to nectar robbing imposes costs in terms of decreased pollinator attraction and reproduction. © 2016 Botanical Society of America.

Hypohydration Reduces Vertical Ground Reaction Impulse But Not Jump Height

Science.gov (United States)

2010-01-01

height, provided that muscle contractile function remains normal, because gravitational and inertial resistance to jumping are pro- portional to body...testing, anthropometric and fitness measurements were made to characterize the study population. Peak aerobic power (VO2peak) was determined using an...determinations. All volunteers performed between 3 and 5 practice days of vertical jump testing to reduce training and learning effects. Practice

Application of Low Voltage High Resistance Grounding in Nuclear Power Plants

Directory of Open Access Journals (Sweden)

Choong-Koo Chang

2016-02-01

Full Text Available Most nuclear power plants now utilize solid grounded low voltage systems. For safety and reliability reasons, the low voltage (LV high resistance grounding (HRG system is also increasingly used in the pulp and paper, petroleum and chemical, and semiconductor industries. Fault detection is easiest and fastest with a solidly grounded system. However, a solidly grounded system has many limitations such as severe fault damage, poor reliability on essential circuits, and electrical noise caused by the high magnitude of ground fault currents. This paper will briefly address the strengths and weaknesses of LV grounding systems. An example of a low voltage HRG system in the LV system of a nuclear power plant will be presented. The HRG system is highly recommended for LV systems of nuclear power plants if sufficient considerations are provided to prevent nuisance tripping of ground fault relays and to avoid the deterioration of system reliability.

Response morphology and anatomy of tobacco (Nicotiana tabacum L.) plant on waterlogging

Science.gov (United States)

Nurhidayati, Tutik; Wardhani, Selfrina Puri; Purnobasuki, Hery; Hariyanto, Sucipto; Jadid, Nurul; Nurcahyani, Desy Dwi

2017-11-01

This study has conducted research on morphological and anatomical responses of some varieties of tobacco plants to waterlogging stress. Parameters measured were morphology, anatomy, and plants sensitivity index. Results were analyzed using two-way ANOVA followed by the Tukey test. The results show that waterlogging stress can reduce the growth of tobacco plants, including a decrease in plant height with the lowest value of 15.6 cm, root length reduction to the lowest value of 4.6 cm and plant dry weight reduction to the lowest value of 0.26 gr. But waterlogging stress can increase the number of adventitious roots with the highest value of 18.33. In addition, waterlogging stress can lead to the formation of aerenchyma tissue. The sensitivity index showed that plant varieties that are resistant to waterlogging stress are the varieties Kemloko 3 (index value of 0.03), varieties of Paiton 2 (index value of 0.18), and the varieties Kemloko 2 (index value of 0.42).

Antibiotic-resistant genes and antibiotic-resistant bacteria in the effluent of urban residential areas, hospitals, and a municipal wastewater treatment plant system.

Science.gov (United States)

Li, Jianan; Cheng, Weixiao; Xu, Like; Strong, P J; Chen, Hong

2015-03-01

In this study, we determined the abundance of 8 antibiotics (3 tetracyclines, 4 sulfonamides, and 1 trimethoprim), 12 antibiotic-resistant genes (10 tet, 2 sul), 4 antibiotic-resistant bacteria (tetracycline, sulfamethoxazole, and combined resistance), and class 1 integron integrase gene (intI1) in the effluent of residential areas, hospitals, and municipal wastewater treatment plant (WWTP) systems. The concentrations of total/individual targets (antibiotics, genes, and bacteria) varied remarkably among different samples, but the hospital samples generally had a lower abundance than the residential area samples. The WWTP demonstrated removal efficiencies of 50.8% tetracyclines, 66.8% sulfonamides, 0.5 logs to 2.5 logs tet genes, and less than 1 log of sul and intI1 genes, as well as 0.5 log to 1 log removal for target bacteria. Except for the total tetracycline concentration and the proportion of tetracycline-resistant bacteria (R (2) = 0.330, P antibiotics and the corresponding resistant bacteria (P > 0.05). In contrast, various relationships were identified between antibiotics and antibiotic resistance genes (P antibiotic-resistant bacteria (P < 0.01).

Positive feedback between mycorrhizal fungi and plants influences plant invasion success and resistance to invasion.

Science.gov (United States)

Zhang, Qian; Yang, Ruyi; Tang, Jianjun; Yang, Haishui; Hu, Shuijin; Chen, Xin

2010-08-24

Negative or positive feedback between arbuscular mycorrhizal fungi (AMF) and host plants can contribute to plant species interactions, but how this feedback affects plant invasion or resistance to invasion is not well known. Here we tested how alterations in AMF community induced by an invasive plant species generate feedback to the invasive plant itself and affect subsequent interactions between the invasive species and its native neighbors. We first examined the effects of the invasive forb Solidago canadensis L. on AMF communities comprising five different AMF species. We then examined the effects of the altered AMF community on mutualisms formed with the native legume forb species Kummerowia striata (Thunb.) Schindl. and on the interaction between the invasive and native plants. The host preferences of the five AMF were also assessed to test whether the AMF form preferred mutualistic relations with the invasive and/or the native species. We found that S. canadensis altered AMF spore composition by increasing one AMF species (Glomus geosporum) while reducing Glomus mosseae, which is the dominant species in the field. The host preference test showed that S. canadensis had promoted the abundance of AMF species (G. geosporum) that most promoted its own growth. As a consequence, the altered AMF community enhanced the competitiveness of invasive S. canadensis at the expense of K. striata. Our results demonstrate that the invasive S. canadensis alters soil AMF community composition because of fungal-host preference. This change in the composition of the AMF community generates positive feedback to the invasive S. canadensis itself and decreases AM associations with native K. striata, thereby making the native K. striata less dominant.

Positive feedback between mycorrhizal fungi and plants influences plant invasion success and resistance to invasion.

Directory of Open Access Journals (Sweden)

Qian Zhang

2010-08-01

Full Text Available Negative or positive feedback between arbuscular mycorrhizal fungi (AMF and host plants can contribute to plant species interactions, but how this feedback affects plant invasion or resistance to invasion is not well known. Here we tested how alterations in AMF community induced by an invasive plant species generate feedback to the invasive plant itself and affect subsequent interactions between the invasive species and its native neighbors. We first examined the effects of the invasive forb Solidago canadensis L. on AMF communities comprising five different AMF species. We then examined the effects of the altered AMF community on mutualisms formed with the native legume forb species Kummerowia striata (Thunb. Schindl. and on the interaction between the invasive and native plants. The host preferences of the five AMF were also assessed to test whether the AMF form preferred mutualistic relations with the invasive and/or the native species. We found that S. canadensis altered AMF spore composition by increasing one AMF species (Glomus geosporum while reducing Glomus mosseae, which is the dominant species in the field. The host preference test showed that S. canadensis had promoted the abundance of AMF species (G. geosporum that most promoted its own growth. As a consequence, the altered AMF community enhanced the competitiveness of invasive S. canadensis at the expense of K. striata. Our results demonstrate that the invasive S. canadensis alters soil AMF community composition because of fungal-host preference. This change in the composition of the AMF community generates positive feedback to the invasive S. canadensis itself and decreases AM associations with native K. striata, thereby making the native K. striata less dominant.

Plant Adaptation to Acid Soils: The Molecular Basis for Crop Aluminum Resistance.

Science.gov (United States)

Kochian, Leon V; Piñeros, Miguel A; Liu, Jiping; Magalhaes, Jurandir V

2015-01-01

Aluminum (Al) toxicity in acid soils is a significant limitation to crop production worldwide, as approximately 50% of the world's potentially arable soil is acidic. Because acid soils are such an important constraint to agriculture, understanding the mechanisms and genes conferring resistance to Al toxicity has been a focus of intense research interest in the decade since the last article on crop acid soil tolerance was published in this journal. An impressive amount of progress has been made during that time that has greatly increased our understanding of the diversity of Al resistance genes and mechanisms, how resistance gene expression is regulated and triggered by Al and Al-induced signals, and how the proteins encoded by these genes function and are regulated. This review examines the state of our understanding of the physiological, genetic, and molecular bases for crop Al tolerance, looking at the novel Al resistance genes and mechanisms that have been identified over the past ten years. Additionally, it examines how the integration of molecular and genetic analyses of crop Al resistance is starting to be exploited for the improvement of crop plants grown on acid soils via both molecular-assisted breeding and biotechnology approaches.

High-throughput volumetric reconstruction for 3D wheat plant architecture studies

Directory of Open Access Journals (Sweden)

Wei Fang

2016-09-01

Full Text Available For many tiller crops, the plant architecture (PA, including the plant fresh weight, plant height, number of tillers, tiller angle and stem diameter, significantly affects the grain yield. In this study, we propose a method based on volumetric reconstruction for high-throughput three-dimensional (3D wheat PA studies. The proposed methodology involves plant volumetric reconstruction from multiple images, plant model processing and phenotypic parameter estimation and analysis. This study was performed on 80 Triticum aestivum plants, and the results were analyzed. Comparing the automated measurements with manual measurements, the mean absolute percentage error (MAPE in the plant height and the plant fresh weight was 2.71% (1.08cm with an average plant height of 40.07cm and 10.06% (1.41g with an average plant fresh weight of 14.06g, respectively. The root mean square error (RMSE was 1.37cm and 1.79g for the plant height and plant fresh weight, respectively. The correlation coefficients were 0.95 and 0.96 for the plant height and plant fresh weight, respectively. Additionally, the proposed methodology, including plant reconstruction, model processing and trait extraction, required only approximately 20s on average per plant using parallel computing on a graphics processing unit (GPU, demonstrating that the methodology would be valuable for a high-throughput phenotyping platform.

Cavitation Resistance in Seedless Vascular Plants: The Structure and Function of Interconduit Pit Membranes1[W][OPEN

Science.gov (United States)

Brodersen, Craig; Jansen, Steven; Choat, Brendan; Rico, Christopher; Pittermann, Jarmila

2014-01-01

Plant water transport occurs through interconnected xylem conduits that are separated by partially digested regions in the cell wall known as pit membranes. These structures have a dual function. Their porous construction facilitates water movement between conduits while limiting the spread of air that may enter the conduits and render them dysfunctional during a drought. Pit membranes have been well studied in woody plants, but very little is known about their function in more ancient lineages such as seedless vascular plants. Here, we examine the relationships between conduit air seeding, pit hydraulic resistance, and pit anatomy in 10 species of ferns (pteridophytes) and two lycophytes. Air seeding pressures ranged from 0.8 ± 0.15 MPa (mean ± sd) in the hydric fern Athyrium filix-femina to 4.9 ± 0.94 MPa in Psilotum nudum, an epiphytic species. Notably, a positive correlation was found between conduit pit area and vulnerability to air seeding, suggesting that the rare-pit hypothesis explains air seeding in early-diverging lineages much as it does in many angiosperms. Pit area resistance was variable but averaged 54.6 MPa s m−1 across all surveyed pteridophytes. End walls contributed 52% to the overall transport resistance, similar to the 56% in angiosperm vessels and 64% in conifer tracheids. Taken together, our data imply that, irrespective of phylogenetic placement, selection acted on transport efficiency in seedless vascular plants and woody plants in equal measure by compensating for shorter conduits in tracheid-bearing plants with more permeable pit membranes. PMID:24777347

An antibody that confers plant disease resistance targets a membrane-bound glyoxal oxidase in Fusarium.

Science.gov (United States)

Song, Xiu-Shi; Xing, Shu; Li, He-Ping; Zhang, Jing-Bo; Qu, Bo; Jiang, Jin-He; Fan, Chao; Yang, Peng; Liu, Jin-Long; Hu, Zu-Quan; Xue, Sheng; Liao, Yu-Cai

2016-05-01

Plant germplasm resources with natural resistance against globally important toxigenic Fusarium are inadequate. CWP2, a Fusarium genus-specific antibody, confers durable resistance to different Fusarium pathogens that infect cereals and other crops, producing mycotoxins. However, the nature of the CWP2 target is not known. Thus, investigation of the gene coding for the CWP2 antibody target will likely provide critical insights into the mechanism underlying the resistance mediated by this disease-resistance antibody. Immunoblots and mass spectrometry analysis of two-dimensional electrophoresis gels containing cell wall proteins from Fusarium graminearum (Fg) revealed that a glyoxal oxidase (GLX) is the CWP2 antigen. Cellular localization studies showed that GLX is localized to the plasma membrane. This GLX efficiently catalyzes hydrogen peroxide production; this enzymatic activity was specifically inhibited by the CWP2 antibody. GLX-deletion strains of Fg, F. verticillioides (Fv) and F. oxysporum had significantly reduced virulence on plants. The GLX-deletion Fg and Fv strains had markedly reduced mycotoxin accumulation, and the expression of key genes in mycotoxin metabolism was downregulated. This study reveals a single gene-encoded and highly conserved cellular surface antigen that is specifically recognized by the disease-resistance antibody CWP2 and regulates both virulence and mycotoxin biosynthesis in Fusarium species. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Creation of glyphosate-resistant Brassica napus L. plants expressing DesC desaturase of cyanobacterium Synechococcus vulcanus

Directory of Open Access Journals (Sweden)

Goldenkova-Pavlova I. V.

2012-12-01

Full Text Available Aim. Creation of glyphosate-resistant canola plants expressing bifunctional hybrid desC::licBM3 gene. In the hybrid gene the sequence of DesC desaturase of cyanobacterium S. vulcanus without plastid targeting was fused with the sequence of thermostable lichenase reporter LicBM3 gene. Methods. Agrobacterium tumefaciens-mediated transformation, PCR, quantitative and qualitative determination of lichenase activity, genetic analysis. Results. Transgenic canola plants, carring the enolpyruvat shikimat phosphate syntase gene (epsps, conferring on plants resistance to phosphonomethyl glycine herbicides (Roundup, as well as the desC::licBM3 gene, were selected. The presence of transgenes was confimed by multiplex PCR. The epsps gene expression in canola was shown at the transcription level, during in vitro growth and after greenhouse herbicide treatment. Activity of the licBM3 gene product as a part of hybrid protein allowed quantitative and qualitative estimation of the desaturase gene expression. Inheritance of heterologous genes and their expression in the first generation were investigated. Conclusions. Transgenic canola plants were obtained, the presence of trangenes in plant genome was proved and expression of the target genes was detected.

Primisulfuron herbicide-resistant tobacco plants: mutant selection in vitro by adventitious shoot formation from cultured leaf discs

International Nuclear Information System (INIS)

Harms, C.T.; DiMaio, J.J.; Jayne, S.M.; Middlesteadt, L.A.; Negrotto, D.V.; Thompson-Taylor, H.; Montoya, A.L.

1991-01-01

A simple procedure has been developed for the rapid and direct selection of herbicide-resistant mutant plants. The procedure uses adventitious shoot formation from suitable explants, such as leaf discs, on a shoot-inducing culture medium containing a toxic herbicide concentration. Resistant green shoots were thus isolated from tobacco (Nicotiana tabacum L.) leaf explants cultured on medium containing 100 μg 1−1 primisulfuron, a new sulfonylurea herbicide. Resistant shoots were recovered from both haploid and diploid explants after UV mutagenesis, as well as without mutagenic treatment. Three mutant plants of separate origin were further analyzed biochemically and genetically. Their acetohydroxyacid synthase (AHAS) enzyme activity was less inhibited by sulfonylurea herbicides than that of unselected, sensitive wild type plants. The extent of inhibition of the AHAS enzyme among the three mutants was different for different sulfonylurea and imidazolinone herbicides suggesting different sites were affected by each mutation. Herbicide tolerance was scored for germinating seedling populations and was found to be inherited as a single dominant nuclear gene. Adventitious shoot formation from cultured leaf discs was used to determine the cross tolerance of mutant plants to various herbicidal AHAS inhibitors. The usefulness of this rapid and direct scheme for mutant selection based on adventitious shoot formation or embryogenesis is discussed. (author)

Salicylic Acid Is Involved in the Basal Resistance of Tomato Plants to Citrus Exocortis Viroid and Tomato Spotted Wilt Virus.

Science.gov (United States)

López-Gresa, M Pilar; Lisón, Purificación; Yenush, Lynne; Conejero, Vicente; Rodrigo, Ismael; Bellés, José María

2016-01-01

Tomato plants expressing the NahG transgene, which prevents accumulation of endogenous salicylic acid (SA), were used to study the importance of the SA signalling pathway in basal defence against Citrus Exocortis Viroid (CEVd) or Tomato Spotted Wilt Virus (TSWV). The lack of SA accumulation in the CEVd- or TSWV-infected NahG tomato plants led to an early and dramatic disease phenotype, as compared to that observed in the corresponding parental Money Maker. Addition of acibenzolar-S-methyl, a benzothiadiazole (BTH), which activates the systemic acquired resistance pathway downstream of SA signalling, improves resistance of NahG tomato plants to CEVd and TSWV. CEVd and TSWV inoculation induced the accumulation of the hydroxycinnamic amides p-coumaroyltyramine, feruloyltyramine, caffeoylputrescine, and feruloylputrescine, and the defence related proteins PR1 and P23 in NahG plants earlier and with more intensity than in Money Maker plants, indicating that SA is not essential for the induction of these plant defence metabolites and proteins. In addition, NahG plants produced very high levels of ethylene upon CEVd or TSWV infection when compared with infected Money Maker plants, indicating that the absence of SA produced additional effects on other metabolic pathways. This is the first report to show that SA is an important component of basal resistance of tomato plants to both CEVd and TSWV, indicating that SA-dependent defence mechanisms play a key role in limiting the severity of symptoms in CEVd- and TSWV-infected NahG tomato plants.

Host range of antibiotic resistance genes in wastewater treatment plant influent and effluent.

Science.gov (United States)

Hultman, Jenni; Tamminen, Manu; Pärnänen, Katariina; Cairns, Johannes; Karkman, Antti; Virta, Marko

2018-04-01

Wastewater treatment plants (WWTPs) collect wastewater from various sources for a multi-step treatment process. By mixing a large variety of bacteria and promoting their proximity, WWTPs constitute potential hotspots for the emergence of antibiotic resistant bacteria. Concerns have been expressed regarding the potential of WWTPs to spread antibiotic resistance genes (ARGs) from environmental reservoirs to human pathogens. We utilized epicPCR (Emulsion, Paired Isolation and Concatenation PCR) to detect the bacterial hosts of ARGs in two WWTPs. We identified the host distribution of four resistance-associated genes (tetM, int1, qacEΔ1and blaOXA-58) in influent and effluent. The bacterial hosts of these resistance genes varied between the WWTP influent and effluent, with a generally decreasing host range in the effluent. Through 16S rRNA gene sequencing, it was determined that the resistance gene carrying bacteria include both abundant and rare taxa. Our results suggest that the studied WWTPs mostly succeed in decreasing the host range of the resistance genes during the treatment process. Still, there were instances where effluent contained resistance genes in bacterial groups not carrying these genes in the influent. By permitting exhaustive profiling of resistance-associated gene hosts in WWTP bacterial communities, the application of epicPCR provides a new level of precision to our resistance gene risk estimates.

Effect of barnacle fouling on ship resistance and powering.

Science.gov (United States)

Demirel, Yigit Kemal; Uzun, Dogancan; Zhang, Yansheng; Fang, Ho-Chun; Day, Alexander H; Turan, Osman

2017-11-01

Predictions of added resistance and the effective power of ships were made for varying barnacle fouling conditions. A series of towing tests was carried out using flat plates covered with artificial barnacles. The tests were designed to allow the examination of the effects of barnacle height and percentage coverage on the resistance and effective power of ships. The drag coefficients and roughness function values were evaluated for the flat plates. The roughness effects of the fouling conditions on the ships' frictional resistances were predicted. Added resistance diagrams were then plotted using these predictions, and powering penalties for these ships were calculated using the diagrams generated. The results indicate that the effect of barnacle size is significant, since a 10% coverage of barnacles each 5 mm in height caused a similar level of added power requirements to a 50% coverage of barnacles each 1.25 mm in height.

Whole-Body and Hepatic Insulin Resistance in Obese Children

Science.gov (United States)

Ibarra-Reynoso, Lorena del Rocío; Pisarchyk, Liudmila; Pérez-Luque, Elva Leticia; Garay-Sevilla, Ma. Eugenia; Malacara, Juan Manuel

2014-01-01

Background Insulin resistance may be assessed as whole body or hepatic. Objective To study factors associated with both types of insulin resistance. Methods Cross-sectional study of 182 obese children. Somatometric measurements were registered, and the following three adiposity indexes were compared: BMI, waist-to-height ratio and visceral adiposity. Whole-body insulin resistance was evaluated using HOMA-IR, with 2.5 as the cut-off point. Hepatic insulin resistance was considered for IGFBP-1 level quartiles 1 to 3 (HOMA-IR was negatively associated with IGFBP-1 and positively associated with BMI, triglycerides, leptin and mother's BMI. Girls had increased HOMA-IR. IGFBP-1 was negatively associated with waist-to-height ratio, age, leptin, HOMA-IR and IGF-I. We did not find HOMA-IR or IGFBP-1 associated with fatty liver. Conclusion In school-aged children, BMI is the best metric to predict whole-body insulin resistance, and waist-to-height ratio is the best predictor of hepatic insulin resistance, indicating that central obesity is important for hepatic insulin resistance. The reciprocal negative association of IGFBP-1 and HOMA-IR may represent a strong interaction of the physiological processes of both whole-body and hepatic insulin resistance. PMID:25411786

Belowground Carbon Allocation and Plant-Microbial Interactions Drive Resistance and Resilience of Mountain Grassland Communities to Drought

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Karlowsky, S.; Augusti, A.; Ingrisch, J.; Hasibeder, R.; Lavorel, S.; Bahn, M.; Gleixner, G.

2016-12-01

Belowground carbon allocation (BCA) and plant-microbial interactions are crucial for the functioning of terrestrial ecosystems. Recent research suggests that extreme events can have severe effects on these processes but it is unknown how land use intensity potentially modifies their responses. We studied the resistance and resilience of mountain grassland communities to prolonged drought and investigated the role of plant C allocation and soil microbial communities in mediating drought resistance and immediate recovery. In a common garden experiment we exposed monoliths from an abandoned grassland and a hay meadow to an early summer drought. Two independent 13C pulse labeling experiments were conducted, the first during peak drought and the second during the recovery phase. The 13C incorporation was analyzed in above- and belowground plant parts and in phospho- and neutral lipid fatty acids of soil microorganisms. In addition, a 15N label was added at the rewetting to determine plant N uptake. We found that C uptake, BCA and C transfer to soil microorganisms were less strongly reduced by drought in the abandoned grassland than in the meadow. Moreover, drought induced an increase of arbuscular mycorrhiza fungi (AMF) marker in the abandoned grassland. Nevertheless, C uptake and related parameters were quickly recovered and N uptake increased in the meadow during recovery. Unexpectedly, AMF and their C uptake were generally reduced during recovery, while bacteria increased and quickly recovered C uptake, particularly in the meadow. Our results showed a negative relation between high resistance and fast recovery. The more resistant abandoned grassland plant communities seemed to invest more C below ground and into interactions with AMF during drought, likely to access water through their hyphal network. Conversely, meadow communities invested more C from recent photosynthesis into bacterial communities during recovery, obviously to gain more nutrients for regrowth

Particles of bottom and suspended sediments: height of rise

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Khodzinskaya Anna Gennadievna

2014-12-01

Full Text Available In the article, characteristic values of dynamic sizes of bottom and suspended sediments, including their probabilistic assessment, are considered. The article presents the processing results in respect of the experimental data for bottom and suspended sediments, obtained in the laboratory environment using samples and filming methods. The experiments have proven that the dynamic hydraulic size determines the height of rise for the particles of the saltation load, rather than suspended ones. In the laboratory environment, the maximal height of rise is mainly driven by the relative flow depth. According to the assessment made by the co-authors, depths of flows employed in the experiments designated for the identification of heights of rises, were comparable to saltation heights of particles. Besides, the saltation height of particles, having relative density well below 2.65, nearly always exceeded half of the depth of the laboratory flow. Hydrodynamic conditions favourable for the separation and motion of artificial particles in coarse surface tanks are far different from the motion of sand particles on the bottom of lowland rivers. Values of hydraulic resistance ratios typical for laboratory experiments by far exceed their values typical for lowland rivers, and it means that the conditions of the experiments performed in the laboratory were similar to those typical for mountain rivers. The research findings have proven that the particle separation and motion pattern, if artificial particles are made of the materials demonstrating variable density and elasticity values and if loose particles travel over fixed ones, is different from the pattern typical for natural particles having variable coarseness.

Agreement between measured height, and height predicted from ...

African Journals Online (AJOL)

lower limb measurements, such as knee height, as well as upper limb measures ... had with bone injuries/fractures affecting height or ulna length; and n = 1 had a ... and heels, buttocks and upper back in contact with the vertical surface of the .... found striking similarity in linear growth of infants to five-year- olds among all ...

A Multiple Decrement Life Table Reveals That Host Plant Resistance and Parasitism Are Major Causes of Mortality for the Wheat Stem Sawfly.

Science.gov (United States)

Buteler, Micaela; Peterson, Robert K D; Hofland, Megan L; Weaver, David K

2015-12-01

This study investigated the dynamics of parasitism, host plant resistance, pathogens, and predation on the demography of wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), developing in susceptible (hollow stem) and resistant (solid stem) wheat hosts. This study is also the first to investigate the prevalence and impact of cannibalism on wheat stem sawfly mortality. Wheat stem sawflies were sampled in two commercial wheat fields over 4 yr from the egg stage through adult emergence, and multiple decrement life tables were constructed and analyzed. Cannibalism, host plant resistance, or unknown factors were the most prevalent factors causing egg mortality. Summer mortality of prediapause larvae ranged from 28 to 84%, mainly due to parasitism by Bracon cephi (Gahan) and Bracon lissogaster Muesebeck, cannibalism, and host plant resistance. Winter mortality ranged from 6 to 54% of the overwintering larvae, mainly due to unknown factors or pathogens. Cannibalism is a major cause of irreplaceable mortality because it is absolute, with only a single survivor in every multiple infested stem. Subsequent to obligate cannibalism, mortality of feeding larvae due to host plant resistance was lower in hollow stem wheat than in solid stem wheat. Mortality from host plant resistance was largely irreplaceable. Irreplaceable mortality due to parasitoids was greater in hollow stem wheat than in solid stem wheat. Host plant resistance due to stem solidness and parasitism in hollow stems cause substantial mortality in populations of actively feeding larvae responsible for all crop losses. Therefore, enhancing these mortality factors is vital to effective integrated pest management of wheat stem sawfly. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Accuracy of recumbent height measurement.

Science.gov (United States)

Gray, D S; Crider, J B; Kelley, C; Dickinson, L C

1985-01-01

Since many patients requiring specialized nutritional support are bedridden, measurement of height for purposes of nutritional assessment or prescription must often be done with the patient in bed. This study examined the accuracy of measuring body height in bed in the supine position. Two measurements were performed on 108 ambulatory inpatients: (1) standing height using a standard height-weight scale, and (2) bed height using a flexible tape. Patients were divided into four groups based on which of two researchers performed each of the two measurements. Each patient was also weighed and self-reported height, weight, sex, and age were recorded. Bed height was significantly longer than standing height by 3.68 cm, but the two measurements were equally precise. It was believed, however, that this 2% difference was probably not clinically significant in most circumstances. Bed height correlated highly with standing height (r = 0.95), and the regression equation was standing height = 13.82 +/- 0.09 bed height. Patients overestimated their heights. Heights recorded by nurses were more accurate when patients were measured than when asked about their heights, but the patients were more often asked than measured.

Engineering Plant Immunity: Using CRISPR/Cas9 to Generate Virus Resistance

KAUST Repository

Zaidi, Syed Shan-e-Ali

2016-11-08

Plant viruses infect many economically important crops, including wheat, cotton, maize, cassava, and other vegetables. These viruses pose a serious threat to agriculture worldwide, as decreases in cropland area per capita may cause production to fall short of that required to feed the increasing world population. Under these circumstances, conventional strategies can fail to control rapidly evolving and emerging plant viruses. Genome-engineering strategies have recently emerged as promising tools to introduce desirable traits in many eukaryotic species, including plants. Among these genome engineering technologies, the CRISPR (clustered regularly interspaced palindromic repeats)/CRISPR-associated 9 (CRISPR/Cas9) system has received special interest because of its simplicity, efficiency, and reproducibility. Recent studies have used CRISPR/Cas9 to engineer virus resistance in plants, either by directly targeting and cleaving the viral genome, or by modifying the host plant genome to introduce viral immunity. Here, we briefly describe the biology of the CRISPR/Cas9 system and plant viruses, and how different genome engineering technologies have been used to target these viruses. We further describe the main findings from recent studies of CRISPR/Cas9-mediated viral interference and discuss how these findings can be applied to improve global agriculture. We conclude by pinpointing the gaps in our knowledge and the outstanding questions regarding CRISPR/Cas9-mediated viral immunity.

Engineering Plant Immunity: Using CRISPR/Cas9 to Generate Virus Resistance

KAUST Repository

Zaidi, Syed Shan-e-Ali; Tashkandi, Manal; Mansoor, Shahid; Mahfouz, Magdy M.

2016-01-01

Plant viruses infect many economically important crops, including wheat, cotton, maize, cassava, and other vegetables. These viruses pose a serious threat to agriculture worldwide, as decreases in cropland area per capita may cause production to fall short of that required to feed the increasing world population. Under these circumstances, conventional strategies can fail to control rapidly evolving and emerging plant viruses. Genome-engineering strategies have recently emerged as promising tools to introduce desirable traits in many eukaryotic species, including plants. Among these genome engineering technologies, the CRISPR (clustered regularly interspaced palindromic repeats)/CRISPR-associated 9 (CRISPR/Cas9) system has received special interest because of its simplicity, efficiency, and reproducibility. Recent studies have used CRISPR/Cas9 to engineer virus resistance in plants, either by directly targeting and cleaving the viral genome, or by modifying the host plant genome to introduce viral immunity. Here, we briefly describe the biology of the CRISPR/Cas9 system and plant viruses, and how different genome engineering technologies have been used to target these viruses. We further describe the main findings from recent studies of CRISPR/Cas9-mediated viral interference and discuss how these findings can be applied to improve global agriculture. We conclude by pinpointing the gaps in our knowledge and the outstanding questions regarding CRISPR/Cas9-mediated viral immunity.

Generation of Resistance to the Diphenyl Ether Herbicide, Oxyfluorfen, via Expression of the Bacillus subtilis Protoporphyrinogen Oxidase Gene in Transgenic Tobacco Plants.

Science.gov (United States)

Choi, K W; Han, O; Lee, H J; Yun, Y C; Moon, Y H; Kim, M; Kuk, Y I; Han, S U; Guh, J O

1998-01-01

In an effort to develop transgenic plants resistant to diphenyl ether herbicides, we introduced the protoporphyrinogen oxidase (EC 1.3.3.4) gene of Bacillus subtilis into tobacco plants. The results from a Northern analysis and leaf disc assay indicate that the expression of the B. subtilis protoporphyrinogen oxidase gene under the cauliflower mosaic virus 35S promoter generated resistance to the diphenyl ether herbicide, oxyfluorfen, in transgenic tobacco plants.

Comparative evaluation of hemodynamic and respiratory parameters during mechanical ventilation with two tidal volumes calculated by demi-span based height and measured height in normal lungs

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L Mousavi Seresht

2014-01-01

Full Text Available Background : Appropriate determination of tidal volume (VT is important for preventing ventilation induced lung injury. We compared hemodynamic and respiratory parameters in two conditions of receiving VTs calculated by using body weight (BW, which was estimated by measured height (HBW or demi-span based body weight (DBW. Materials and Methods : This controlled-trial was conducted in St. Alzahra Hospital in 2009 on American Society of Anesthesiologists (ASA I and II, 18-65-years-old patients. Standing height and weight were measured and then height was calculated using demi-span method. BW and VT were calculated with acute respiratory distress syndrome-net formula. Patients were randomized and then crossed to receive ventilation with both calculated VTs for 20 min. Hemodynamic and respiratory parameters were analyzed with SPSS version 20.0 using univariate and multivariate analyses. Results : Forty nine patients were studied. Demi-span based body weight and thus VT (DTV were lower than Height based body weight and VT (HTV (P = 0.028, in male patients (P = 0.005. Difference was observed in peak airway pressure (PAP and airway resistance (AR changes with higher PAP and AR at 20 min after receiving HTV compared with DTV. Conclusions : Estimated VT based on measured height is higher than that based on demi-span and this difference exists only in females, and this higher VT results higher airway pressures during mechanical ventilation.

Chromium Resistant Bacteria: Impact on Plant Growth in Soil Microcosm

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Sayel Hanane

2014-07-01

Full Text Available Three chromium resistant bacterial strains, Pseudomonas fluorescens PF28, Enterobacter amnigenus EA31 and Enterococcus gallinarum S34 isolated from tannery waste contaminated soil were used in this study. All strains could resist a high concentration of K2Cr2O7 that is up to 300 mg/L. The effect of these strains on clover plants (Trifolium campestre in the presence of two chromium salts CrCl3 and K2Cr2O7 was studied in soil microcosm. Application of chromium salts adversely affected seed germination, root and shoot length. Bacterial inoculation improved the growth parameters under chromate stress when compared with non inoculated respective controls. There was observed more than 50% reduction of Cr(VI in inoculated soil microcosms, as compared to the uninoculated soil under the same conditions. The results obtained in this study are significant for the bioremediation of chromate pollution.

Disease interactions in a shared host plant: effects of pre-existing viral infection on cucurbit plant defense responses and resistance to bacterial wilt disease.

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Lori R Shapiro

Full Text Available Both biotic and abiotic stressors can elicit broad-spectrum plant resistance against subsequent pathogen challenges. However, we currently have little understanding of how such effects influence broader aspects of disease ecology and epidemiology in natural environments where plants interact with multiple antagonists simultaneously. In previous work, we have shown that healthy wild gourd plants (Cucurbita pepo ssp. texana contract a fatal bacterial wilt infection (caused by Erwinia tracheiphila at significantly higher rates than plants infected with Zucchini yellow mosaic virus (ZYMV. We recently reported evidence that this pattern is explained, at least in part, by reduced visitation of ZYMV-infected plants by the cucumber beetle vectors of E. tracheiphila. Here we examine whether ZYMV-infection may also directly elicit plant resistance to subsequent E. tracheiphila infection. In laboratory studies, we assayed the induction of key phytohormones (SA and JA in single and mixed infections of these pathogens, as well as in response to the feeding of A. vittatum cucumber beetles on healthy and infected plants. We also tracked the incidence and progression of wilt disease symptoms in plants with prior ZYMV infections. Our results indicate that ZYMV-infection slightly delays the progression of wilt symptoms, but does not significantly reduce E. tracheiphila infection success. This observation supports the hypothesis that reduced rates of wilt disease in ZYMV-infected plants reflect reduced visitation by beetle vectors. We also documented consistently strong SA responses to ZYMV infection, but limited responses to E. tracheiphila in the absence of ZYMV, suggesting that the latter pathogen may effectively evade or suppress plant defenses, although we observed no evidence of antagonistic cross-talk between SA and JA signaling pathways. We did, however, document effects of E. tracheiphila on induced responses to herbivory that may influence host-plant

In vitro assay for the anti-Brucella activity of medicinal plants against tetracycline-resistant Brucella melitensis.

Science.gov (United States)

Motamedi, Hossein; Darabpour, Esmaeil; Gholipour, Mahnaz; Seyyed Nejad, Seyyed Mansour

2010-07-01

Brucellosis, a zoonosis caused by four species of brucella, has a high morbidity. Brucella melitensis is the main causative agent of brucellosis in both human and small ruminants. As an alternative to conventional antibiotics, medicinal plants are valuable resources for new agents against antibiotic-resistant strains. The aim of this study was to investigate the usage of native plants for brucellosis treatment. For this purpose, the anti-brucella activities of ethanolic and methanolic extracts of Salvia sclarea, Oliveria decumbens, Ferulago angulata, Vitex pseudo-negundo, Teucrium polium, Plantago ovata, Cordia myxa, and Crocus sativus were assessed. The activity against a resistant Br. melitensis strain was determined by disc diffusion method at various concentrations from 50-400 mg/ml. Antibiotic discs were also used as a control. Among the evaluated herbs, six plant (Salvia sclarea, Oliveria decumbens, Ferulago angulata, Vitex pseudo-negundo, Teucrium polium, and Crocus sativus) showed anti-brucella activity. Oliveria decumbens was chosen as the most effective plant for further studies. A tested isolate exhibited resistance to tetracycline, nafcillin, oxacillin, methicillin, and colistin. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values for Oliveria decumbens against resistant Br. melitensis were the same (5 mg/ml), and for gentamicin they were both 2 mg/ml. Time-kill kinetics for a methanolic extract of Oliveria decumbens was 7 h whereas for an ethanolic extract it was 28 h. Also, Oliveria decumbens extracts showed a synergistic effect in combination with doxycycline and tetracycline. In general, the similar values of MIC and MBC for Oliveria decumbens suggest that these extracts could act as bactericidal agents against Br. melitensis. In addition to Oliveria decumbens, Crocus sativus and Salvia sclarea also had good anti-brucella activity and these should be considered for further study.

In vitro assay for the anti-brucella activity of medicinal plants against tetracycline-resistant Brucella melitensis *

Science.gov (United States)

Motamedi, Hossein; Darabpour, Esmaeil; Gholipour, Mahnaz; Seyyed Nejad, Seyyed Mansour

2010-01-01

Brucellosis, a zoonosis caused by four species of brucella, has a high morbidity. Brucella melitensis is the main causative agent of brucellosis in both human and small ruminants. As an alternative to conventional antibiotics, medicinal plants are valuable resources for new agents against antibiotic-resistant strains. The aim of this study was to investigate the usage of native plants for brucellosis treatment. For this purpose, the anti-brucella activities of ethanolic and methanolic extracts of Salvia sclarea, Oliveria decumbens, Ferulago angulata, Vitex pseudo-negundo, Teucrium polium, Plantago ovata, Cordia myxa, and Crocus sativus were assessed. The activity against a resistant Br. melitensis strain was determined by disc diffusion method at various concentrations from 50–400 mg/ml. Antibiotic discs were also used as a control. Among the evaluated herbs, six plant (Salvia sclarea, Oliveria decumbens, Ferulago angulata, Vitex pseudo-negundo, Teucrium polium, and Crocus sativus) showed anti-brucella activity. Oliveria decumbens was chosen as the most effective plant for further studies. A tested isolate exhibited resistance to tetracycline, nafcillin, oxacillin, methicillin, and colistin. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values for Oliveria decumbens against resistant Br. melitensis were the same (5 mg/ml), and for gentamicin they were both 2 mg/ml. Time-kill kinetics for a methanolic extract of Oliveria decumbens was 7 h whereas for an ethanolic extract it was 28 h. Also, Oliveria decumbens extracts showed a synergistic effect in combination with doxycycline and tetracycline. In general, the similar values of MIC and MBC for Oliveria decumbens suggest that these extracts could act as bactericidal agents against Br. melitensis. In addition to Oliveria decumbens, Crocus sativus and Salvia sclarea also had good anti-brucella activity and these should be considered for further study. PMID:20593515

Final height in survivors of childhood cancer compared with Height Standard Deviation Scores at diagnosis.

Science.gov (United States)

Knijnenburg, S L; Raemaekers, S; van den Berg, H; van Dijk, I W E M; Lieverst, J A; van der Pal, H J; Jaspers, M W M; Caron, H N; Kremer, L C; van Santen, H M

2013-04-01

Our study aimed to evaluate final height in a cohort of Dutch childhood cancer survivors (CCS) and assess possible determinants of final height, including height at diagnosis. We calculated standard deviation scores (SDS) for height at initial cancer diagnosis and height in adulthood in a cohort of 573 CCS. Multivariable regression analyses were carried out to estimate the influence of different determinants on height SDS at follow-up. Overall, survivors had a normal height SDS at cancer diagnosis. However, at follow-up in adulthood, 8.9% had a height ≤-2 SDS. Height SDS at diagnosis was an important determinant for adult height SDS. Children treated with (higher doses of) radiotherapy showed significantly reduced final height SDS. Survivors treated with total body irradiation (TBI) and craniospinal radiation had the greatest loss in height (-1.56 and -1.37 SDS, respectively). Younger age at diagnosis contributed negatively to final height. Height at diagnosis was an important determinant for height SDS at follow-up. Survivors treated with TBI, cranial and craniospinal irradiation should be monitored periodically for adequate linear growth, to enable treatment on time if necessary. For correct interpretation of treatment-related late effects studies in CCS, pre-treatment data should always be included.

Salicylic Acid Is Involved in the Basal Resistance of Tomato Plants to Citrus Exocortis Viroid and Tomato Spotted Wilt Virus.

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M Pilar López-Gresa

Full Text Available Tomato plants expressing the NahG transgene, which prevents accumulation of endogenous salicylic acid (SA, were used to study the importance of the SA signalling pathway in basal defence against Citrus Exocortis Viroid (CEVd or Tomato Spotted Wilt Virus (TSWV. The lack of SA accumulation in the CEVd- or TSWV-infected NahG tomato plants led to an early and dramatic disease phenotype, as compared to that observed in the corresponding parental Money Maker. Addition of acibenzolar-S-methyl, a benzothiadiazole (BTH, which activates the systemic acquired resistance pathway downstream of SA signalling, improves resistance of NahG tomato plants to CEVd and TSWV. CEVd and TSWV inoculation induced the accumulation of the hydroxycinnamic amides p-coumaroyltyramine, feruloyltyramine, caffeoylputrescine, and feruloylputrescine, and the defence related proteins PR1 and P23 in NahG plants earlier and with more intensity than in Money Maker plants, indicating that SA is not essential for the induction of these plant defence metabolites and proteins. In addition, NahG plants produced very high levels of ethylene upon CEVd or TSWV infection when compared with infected Money Maker plants, indicating that the absence of SA produced additional effects on other metabolic pathways. This is the first report to show that SA is an important component of basal resistance of tomato plants to both CEVd and TSWV, indicating that SA-dependent defence mechanisms play a key role in limiting the severity of symptoms in CEVd- and TSWV-infected NahG tomato plants.

Comparison of the developmental response of diploid and tetraploid phalaris following irradiation on the dry seed - : Effect on tiller height, number of branches per tiller and number of tillers per plant

International Nuclear Information System (INIS)

Prasad, A.B.; Godward, M.B.E.

1974-01-01

The influence of 10 kR and 30 kR soft X-rays applied to dry and dormant seeds of Phalaris canariensis Linn (2n=12) and Phalaris minor Retz (4n - +2 = 28) was studied on tiller height, number of branches per tiller and number of tillers per plant at maturity and it was found that different characters responded differently to irradiation. Variation in response to irradiation in both species has been assigned to their differences in the genotypic constitution. An attempt has also been made to explain the role of inhibitor(s) in controlling the height of the tiller. (author)

Root inoculation with Pseudomonas putida KT2440 induces transcriptional and metabolic changes and systemic resistance in maize plants

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Chantal ePlanchamp

2015-01-01

Full Text Available Pseudomonas putida KT2440 (KT2440 rhizobacteria colonize a wide range of plants. They have been extensively studied for their capacity to adhere to maize seeds, to tolerate toxic secondary metabolites produced by maize roots and to be attracted by maize roots. However, the response of maize plants to KT2440 colonization has not been investigated yet. Maize roots were inoculated with KT2440 and the local (roots and systemic (leaves early plant responses were investigated. The colonization behavior of KT2440 following application to maize seedlings was investigated and transcriptional analysis of stress- and defense-related genes as well as metabolite profiling of local and systemic maize tissues of KT2440-inoculated were performed. The local and systemic responses differed and more pronounced changes were observed in roots compared to leaves. Early in the interaction roots responded via jasmonic acid- and abscisic acid-dependent signaling. Interestingly, during later steps, the salicylic acid pathway was suppressed. Metabolite profiling revealed the importance of plant phospholipids in KT2440-maize interactions. An additional important maize secondary metabolite, a form of benzoxazinone, was also found to be differently abundant in roots three days after KT2440 inoculation. However, the transcriptional and metabolic changes observed in bacterized plants early during the interaction were minor and became even less pronounced with time, indicating an accommodation state of the plant to the presence of KT2440. Since the maize plants reacted to the presence of KT2440 in the rhizosphere, we also investigated the ability of these bacteria to trigger induced systemic resistance (ISR against the maize anthracnose fungus Colletotrichum graminicola. The observed resistance was expressed as strongly reduced leaf necrosis and fungal development in infected bacterized plants compared to non-bacterized controls, showing the potential of KT2440 to act as

Social inequalities in height: persisting differences today depend upon height of the parents.

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Bruna Galobardes

Full Text Available Substantial increases in height have occurred concurrently with economic development in most populations during the last century. In high-income countries, environmental exposures that can limit genetic growth potential appear to have lessened, and variation in height by socioeconomic position may have diminished. The objective of this study is to investigate inequalities in height in a cohort of children born in the early 1990s in England, and to evaluate which factors might explain any identified inequalities.12,830 children from The Avon Longitudinal Study of Parents and Children (ALSPAC, a population based cohort from birth to about 11.5 years of age, were used in this analysis. Gender- and age-specific z-scores of height at different ages were used as outcome variables. Multilevel models were used to take into account the repeated measures of height and to analyze gender- and age-specific relative changes in height from birth to 11.5 years. Maternal education was the main exposure variable used to examine socioeconomic inequalities. The roles of parental and family characteristics in explaining any observed differences between maternal education and child height were investigated. Children whose mothers had the highest education compared to those with none or a basic level of education, were 0.39 cm longer at birth (95% CI: 0.30 to 0.48. These differences persisted and at 11.5 years the height difference was 1.4 cm (95% CI: 1.07 to 1.74. Several other factors were related to offspring height, but few changed the relationship with maternal education. The one exception was mid-parental height, which fully accounted for the maternal educational differences in offspring height.In a cohort of children born in the 1990s, mothers with higher education gave birth to taller boys and girls. Although height differences were small they persisted throughout childhood. Maternal and paternal height fully explained these differences.

Isolation and characterization of antimicrobial compounds in plant extracts against multidrug-resistant Acinetobacter baumannii.

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Yoko Miyasaki

Full Text Available The number of fully active antibiotic options that treat nosocomial infections due to multidrug-resistant Acinetobacter baumannii (A. baumannii is extremely limited. Magnolia officinalis, Mahonia bealei, Rabdosia rubescens, Rosa rugosa, Rubus chingii, Scutellaria baicalensis, and Terminalia chebula plant extracts were previously shown to have growth inhibitory activity against a multidrug-resistant clinical strain of A. baumannii. In this study, the compounds responsible for their antimicrobial activity were identified by fractionating each plant extract using high performance liquid chromatography, and determining the antimicrobial activity of each fraction against A. baumannii. The chemical structures of the fractions inhibiting >40% of the bacterial growth were elucidated by liquid chromatography/mass spectrometry analysis and nuclear magnetic resonance spectroscopy. The six most active compounds were identified as: ellagic acid in Rosa rugosa; norwogonin in Scutellaria baicalensis; and chebulagic acid, chebulinic acid, corilagin, and terchebulin in Terminalia chebula. The most potent compound was identified as norwogonin with a minimum inhibitory concentration of 128 µg/mL, and minimum bactericidal concentration of 256 µg/mL against clinically relevant strains of A. baumannii. Combination studies of norwogonin with ten anti-Gram negative bacterial agents demonstrated that norwogonin did not enhance the antimicrobial activity of the synthetic antibiotics chosen for this study. In conclusion, of all identified antimicrobial compounds, norwogonin was the most potent against multidrug-resistant A. baumannii strains. Further studies are warranted to ascertain the prophylactic and therapeutic potential of norwogonin for infections due to multidrug-resistant A. baumannii.

Overexpression of NtPR-Q Up-Regulates Multiple Defense-Related Genes in Nicotiana tabacum and Enhances Plant Resistance to Ralstonia solanacearum

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Yuanman Tang

2017-11-01

Full Text Available Various classes of plant pathogenesis-related proteins have been identified in the past several decades. PR-Q, a member of the PR3 family encoding chitinases, has played an important role in regulating plant resistance and preventing pathogen infection. In this paper, we functionally characterized NtPR-Q in tobacco plants and found that the overexpression of NtPR-Q in tobacco Yunyan87 resulted in higher resistance to Ralstonia solanacearum inoculation. Surprisingly, overexpression of NtPR-Q led to the activation of many defense-related genes, such as salicylic acid (SA-responsive genes NtPR1a/c, NtPR2 and NtCHN50, JA-responsive gene NtPR1b and ET production-associated genes NtACC Oxidase and NtEFE26. Consistent with the role of NtPR-Q in multiple stress responses, NtPR-Q transcripts were induced by the exogenous hormones SA, ethylene and methyl jasmonate, which could enhance the resistance of tobacco to R. solanacearum. Collectively, our results suggested that NtPR-Q overexpression led to the up-regulation of defense-related genes and enhanced plant resistance to R. solanacearum infection.

A resistance representation of schemes for evaporation from bare and partly plant-covered surfaces for use in atmospheric models

Energy Technology Data Exchange (ETDEWEB)

Mihailovic, D.T.; Pielke, R.A.; Rajkovic, B.; Lee, T.J.; Jeftic, M. (Novi Sad Univ. (Yugoslavia) Colorado State Univ., Fort Collins (United States) Belgrade Univ. (Yugoslavia))

1993-06-01

In the parameterization of land surface processes, attention must be devoted to surface evaporation, one of the main processes in the air-land energy exchange. One of the most used approaches is the resistance representation which requires the calculation of aerodynamic resistances. These resistances are calculated using K theory for different morphologies of plant communities; then, the performance of the evaporation schemes within the alpha, beta, and their combination approaches that parameterize evaporation from bare and partly plant-covered soil surfaces are discussed. Additionally, a new alpha scheme is proposed based on an assumed power dependence alpha on volumetric soil moisture content and its saturated value. Finally, the performance of the considered and the proposed schemes is tested based on time integrations using real data. The first set was for 4 June 1982, and the second for 3 June 1981 at the experimental site in Rimski Sancevi, Yugoslavia, on chernozem soil, as representative for a bare, and partly plant-covered surface, respectively. 63 refs.