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Perez-Mendoza J Throne JE Maghirang EB Dowell FE Baker JE 《Journal of economic entomology》2005,98(6):2282-2291
We determined that the number of insect fragments, quantified using the standard flotation method, in flour milled from wheat infested with larvae, pupae, or preemergent adults of the lesser grain borer, Rhyzopertha dominica (F.), was proportional to infestation level. Wheat infested with a single preemergent adult contributed 28 and 10x as many fragments as wheat infested with a single larva or pupa, respectively. Using regression models that were developed from these data, we predicted that the maximum infestation level that would result in flour with fragment counts below the Food and Drug Administration defect action level (75 fragments/50 g of flour) was 0.95 and 1.5% (380-640 infested kernels/kg of wheat) for pupae and larvae, but it decreased to 0.05% (20 infested kernels/kg) when the grain was infested with preemergent adults. We also reexamined the accuracy and sensitivity of near-infrared spectroscopy (NIRS) for detecting insect fragments in flour by testing three different NIR spectrometers. NIRS-predicted numbers of insect fragments were correlated with the actual number of fragments. NIRS is less precise than the standard flotation method, but it is rapid, nondestructive, does not require extensive sample preparation, and could easily be automated for a more sophisticated sampling protocol for flour based on prescreening samples with NIRS followed up by use of the standard flotation method when necessary. 相似文献
2.
John Darby Taguiam Edzel Evallo Jennelyn Bengoa Rodel Maghirang Mark Angelo Balendres 《Journal of Phytopathology》2020,168(6):303-310
Recent reports of plant diseases that result in yield reduction and increasing demand for dragon fruits raise concerns of fruit supply shortage. Emerging plant diseases may play an important role in increasing yield losses and reducing the availability of stem cuttings (source of planting materials). Understanding the aetiology of current and new diseases of dragon fruit is important to address production issues and to formulate effective disease control measures. This study reports Epicoccum sorghinum as a potential emerging pathogen of dragon fruit. Epicoccum sorghinum MBDF0024a was isolated from dragon fruit stems (Hylocereus monacanthus) showing brown spot symptoms. DNA sequence of the internal transcribed spacer (ITS-rDNA), beta tubulin and actin gene regions of fungal isolate MBDF0024a had high similarities to E. sorghinum stains. Epicoccum sorghinum MBDF0024a was pathogenic to three cultivated dragon fruit species (Hylocereus undatus, H. monacanthus and H. megalanthus) in repeated laboratory and glasshouse trials. Large brown lesions developed on 3-week-old inoculated rooted stem cuttings 3 days postinoculation (dpi). Yellowing of the lesion (advance part) started at five dpi, and at seven dpi, yellowing was observed in the stem. As there are no reported control measures for diseases caused by E. sorghinum, this study screened chemicals with antifungal properties. A biopesticide containing B. subtilis (2 ml/400 ml), and chemicals isoprothiolane (2.25 ml/400 ml), mancozeb (2 g/400 ml) and pyraclostrobin (1 ml/400 ml) (chemical control) completely inhibited the in vitro growth of E. sorghinum MBDF0024a. The results establish E. sorghinum as a new and emerging pathogen of dragon fruit that could be a major yield-limiting disease if left uncontrolled. The biopesticide can be considered a fairly safe option for disease management, but glasshouse and field studies are needed for validation. 相似文献
3.
Near-infrared spectroscopy (NIRS) was used to develop a simple and quick technique to differentiate two economically important species, the tobacco budworm, Heliothis cirescens (F.), and corn earworm, Helicoverpa zea (Boddie), which are major pests of cotton, Gossypium hirsutum L., in the southern United States. In practice, it is difficult to distinguish the two species during their immature stages using morphological characteristics unless expensive microscopy equipment or trained technicians are available. The current studies demonstrated that the two species could be quickly and readily differentiated during early developmental stages, including egg and young larval (younger than third instar) stages, by using NIRS technology with up to 95% accuracy. NIRS technology could significantly improve pest diagnosis in cotton pest management. 相似文献
4.
Genome-wide Introgression Lines and their Use in Genetic and Molecular Dissection of Complex Phenotypes in Rice (Oryza sativa L.) 总被引:15,自引:0,他引:15
Li ZK Fu BY Gao YM Xu JL Ali J Lafitte HR Jiang YZ Rey JD Vijayakumar CH Maghirang R Zheng TQ Zhu LH 《Plant molecular biology》2005,59(1):33-52
Tremendous efforts have been taken worldwide to develop genome-wide genetic stocks for rice functional genomic (FG) research
since the rice genome was completely sequenced. To facilitate FG research of complex polygenic phenotypes in rice, we report
the development of over 20 000 introgression lines (ILs) in three elite rice genetic backgrounds for a wide range of complex
traits, including resistances/tolerances to many biotic and abiotic stresses, morpho-agronomic traits, physiological traits,
etc., by selective introgression. ILs within each genetic background are phenotypically similar to their recurrent parent
but each carries one or a few traits introgressed from a known donor. Together, these ILs contain a significant portion of
loci affecting the selected complex phenotypes at which allelic diversity exists in the primary gene pool of rice. A forward
genetics strategy was proposed and demonstrated with examples on how to use these ILs for large-scale FG research. Complementary
to the genome-wide insertional mutants, these ILs opens a new way for highly efficient discovery, candidate gene identification
and cloning of important QTLs for specific phenotypes based on convergent evidence from QTL position, expression profiling,
functional and molecular diversity analyses of candidate genes, highlights the importance of genetic networks underlying complex
phenotypes in rice that may ultimately lead to more complete understanding of the genetic and molecular bases of quantitative
trait variation in rice.
Supplementary material to this paper is available in electronic form at
http://dx.doi.org/10.1007/s11103-005-8519-3 相似文献
5.
Jin Tong Xin Liu Ronaldo Maghirang Kaiqi Wei Linna Liu Chun Wang Yunhai Ma Donghui Chen Hongjia Yan Li Guo 《仿生工程学报(英文版)》2017,14(2)
Vegetative Barriers (VB) have the potential to mitigate air pollutants emitted from area sources,including concentrated Animal Feeding Operations (AFOs).However,the mechanism has not been fully investigated,thereby limiting the application of vegetation systems in practice.An experimental method with repeatable and controllable conditions was developed to measure the change of Particulate Matter (PM) concentrations at upwind and downwind of VB in the wind tunnel and observe accumulated PM on leaves with Scanning Electron Microscope (SEM),thus evaluating the ability of VB in mitigating PM emitted from AFOs.Branch-scale vegetation,clove (syzygium aromaticum) was selected because its leaves are one of the major factors affecting PM dispersion.The results show that the branch-scale barriers,as porous medium have the ability to interfere with airflow and reduce PM,which could be influenced by wind speed,particle size fraction and surface area density of clove.Moreover,clove elements could adjust to the wind and the micro structure of clove (such as the hierarchical structures of leaves)affected on the PM deposition.These results indicate that the methods developed in this study may be used to evaluate the potential of vegetation in mitigating PM from stationary sources,and some characteristics of vegetation can be further studied as bionic prototype for exploring engineering application of reducing particulates. 相似文献
6.
Toews MD Perez-Mendoza J Throne JE Dowell FE Maghirang E Arthur FH Campbell JF 《Journal of economic entomology》2007,100(5):1714-1723
Milling wheat, Triticum aestivum L., infested with low densities of internal feeding insects can result in flour containing insect fragments. The Food and Drug Administration (FDA) enforces a standard or defect action level stating that a maximum of 75 insect fragments per 50 g of flour is allowed. However, the relationship between level of infestation and number of resulting fragments is not well documented, and a more rapid method for enumerating insect fragments is needed. We characterized the number of insect fragments produced from milling small lots of wheat spiked with known densities and life stages of Sitophilus oryzae (L.) (Coleoptera: Curculionidae). Insect fragments were enumerated with near-infrared spectroscopy (NIRS), a quick nondestructive procedure, and with the industry standard flotation method. Results showed that an individual small larva, large larva, pupa, or adult produced 0.4, 0.7, 1.5, and 27.0 fragments, respectively. NIRS-predicted counts of < or =51 (from small larvae), < or =53 (from large larvae), < or =43 (from pupae), or 0 (from adults) indicated that there were <75 actual fragments in that sample, because the upper bound of associated 95% inverse prediction confidence intervals was less than the standard; NIRS-predicted counts of > or =98, > or =117, 108, or > or =225 fragments (same life stages as above) signaled that these flour samples contained >75 actual fragments. These data suggest that NIRS could be adopted for rapid assessment of insect fragments resulting from relatively low levels of infestation with immature life states, but that it was not accurate enough for enumerating insect fragments, relevant to FDA standards, resulting from adults. 相似文献
7.
Susan R McCouch Leonid Teytelman Yunbi Xu Katarzyna B Lobos Karen Clare Mark Walton Binying Fu Reycel Maghirang Zhikang Li Yongzhong Xing Qifa Zhang Izumi Kono Masahiro Yano Robert Fjellstrom Genevieve DeClerck David Schneider Samuel Cartinhour Doreen Ware Lincoln Stein 《DNA research》2002,9(6):257-279
8.
Susan R McCouch Leonid Teytelman Yunbi Xu Katarzyna B Lobos Karen Clare Mark Walton Binying Fu Reycel Maghirang Zhikang Li Yongzhong Xing Qifa Zhang Izumi Kono Masahiro Yano Robert Fjellstrom Genevieve DeClerck David Schneider Samuel Cartinhour Doreen Ware Lincoln Stein 《DNA research》2002,9(6):199-207
A total of 2414 new di-, tri- and tetra-nucleotide non-redundant SSR primer pairs, representing 2240 unique marker loci, have been developed and experimentally validated for rice (Oryza sativa L.). Duplicate primer pairs are reported for 7% (174) of the loci. The majority (92%) of primer pairs were developed in regions flanking perfect repeats > or = 24 bp in length. Using electronic PCR (e-PCR) to align primer pairs against 3284 publicly sequenced rice BAC and PAC clones (representing about 83% of the total rice genome), 65% of the SSR markers hit a BAC or PAC clone containing at least one genetically mapped marker and could be mapped by proxy. Additional information based on genetic mapping and "nearest marker" information provided the basis for locating a total of 1825 (81%) of the newly designed markers along rice chromosomes. Fifty-six SSR markers (2.8%) hit BAC clones on two or more different chromosomes and appeared to be multiple copy. The largest proportion of SSRs in this data set correspond to poly(GA) motifs (36%), followed by poly(AT) (15%) and poly(CCG) (8%) motifs. AT-rich microsatellites had the longest average repeat tracts, while GC-rich motifs were the shortest. In combination with the pool of 500 previously mapped SSR markers, this release makes available a total of 2740 experimentally confirmed SSR markers for rice, or approximately one SSR every 157 kb. 相似文献
9.
Bioaerosol concentrations inside one naturally ventilated and one mechanically ventilated swine finishing barn were assessed
by sampling air using membrane filtration and impaction (six-stage Andersen sampler), and assayed by culture method. The barns,
located on the same commercial farm in northeast Kansas, did not show any significant difference (p > 0.05) in concentrations of total and respirable airborne microorganisms. The overall mean total concentrations inside the two barns
were 6.6 × 104 colony forming units (CFU)/m3 (SD = 3.8 × 104 CFU/m3) as measured by filtration and 8.6 × 104 CFU/m3 (SD = 5.1 × 104 CFU/m3) by impaction. The overall mean respirable concentrations were 9.0 × 103 CFU/m3 (SD = 4.1 × 103 CFU/m3) measured by filtration and 2.8 × 104 CFU/m3 (SD = 2.2 × 104 CFU/m3) by impaction. Total and respirable CFU concentrations measured by impaction were significantly (p < 0.05) higher than that by filtration. The persistent strains of microorganisms were various species of the following genera: Staphylococcus, Pseudomonas, Bacillus, Listeria, Enterococcus, Nocardia, Lactobacillus, and Penicillium. It appears that filtration sampling can be used for a qualitative survey of bioaerosols in swine barns while the Andersen
sampler is suitable for both quantitative and qualitative assessments.
Received: 2 April 2001 / Accepted: 13 June 2001 相似文献
10.
Roman Dial C Dial RJ Saunders R Lang SA Lee B Wimberger P Dinapoli MS Egiazarov AS Gipple SL Maghirang MR Swartley-McArdle DJ Yudkovitz SR Shain DH 《Molecular phylogenetics and evolution》2012,63(3):577-584
North American ice worms are the largest glacially-obligate metazoans, inhabiting coastal, temperate glaciers between southcentral Alaska and Oregon. We have collected ice worm specimens from 10 new populations, completing a broad survey throughout their geographic range. Phylogenetic analyses of 87 individuals using fragments of nuclear 18S rRNA, and mitochondrial 12S rRNA and cyctochrome c oxidase subunit 1 (CO1) identified 18 CO1 haplotypes with divergence values up to ~10%. Phylogeographic interpretations suggest a St. Elias Range, Alaskan ancestry from an aquatic mesenchytraeid oligochaete during the early-Pliocene. A gradual, northward expansion by active dispersal from the central St. Elias clade characterizes a northern clade that is confined to Alaska (with one exception on Vancouver Island, British Columbia), while a distinct southern clade representing worms from British Columbia, Washington and Oregon was likely founded by a passive dispersal event originating from a northern ancestor. The geographic boundary between central and southern clades coincides with an ice worm distribution gap located in southern Alaska, which appears to have restricted active gene flow throughout the species' evolutionary history. 相似文献
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