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Ramirez-Torres Fabiola Ghogare Rishikesh Stowe Evan Cerdá-Bennasser Pedro Lobato-Gómez Maria Williamson-Benavides Bruce A Giron-Calva Patricia Sarai Hewitt Seanna Christou Paul Dhingra Amit 《Transgenic research》2021,30(4):499-528
Transgenic Research - The advent of genome editing has opened new avenues for targeted trait enhancement in fruit, ornamental, industrial, and all specialty crops. In particular, CRISPR-based... 相似文献
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Mealybugs (Hemiptera: Pseudococcidae) are common invasive pests in Europe, causing major problems on crops and ornamental plants. However, very few data are available concerning the mealybug fauna of southern Europe. This lack of data and the difficulty of identifying mealybugs morphologically by traditional techniques currently limit the perspectives for efficient specific pest management. The aim of this study was to provide multi-criterion characterization of mealybugs surveyed in eastern Spain in order to facilitate their routine identification through DNA sequencing or the use of derived species-specific molecular tools. We characterised 33 mealybug populations infesting crops and ornamental plants in eastern Spain, using a combination of molecular and morphological techniques, including the sequencing of the universal barcode DNA region cytochrome c oxidase subunit I (COI). This characterisation has led to the identification of ten species and provides sequence data for three previously unsequenced species, contributing to the phylogenetic knowledge of the family Pseudococcidae. In addition, the intraspecific variations found in the populations of five mealybug species provide insight into their invasion history. 相似文献
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Pasco B. Avery Vivek Kumar Yingfang Xiao Charles A. Powell Cindy L. McKenzie Lance S. Osborne 《Arthropod-Plant Interactions》2014,8(1):49-56
Preference of phytoseiid mite, Amblyseius swirskii (Athias-Henriot) was assessed on four cultivars of ornamental pepper banker plant candidates; Red Missile (RM), Masquerade (MA), Explosive Ember (EE) and Black Pearl (BP) for potential control of pestiferous insects in floriculture. Significant differences in cultivar preference by A. swirskii was observed in choice experiments whether the test was pre- (with pollen) or during bloom. Overall, female mites laid more eggs when pollen was provided as a food source. The number of tuft domatia per cultivar leaf appeared to positively influence host preference in the choice plant tests pre-bloom. In addition, cultivar RM had the highest mean number ± SEM of tuft domatia per leaf (5.1 ± 0.3) and motiles per plant (4.0 ± 1.2), followed by MA, EE and BP. In choice tests on blooming plants, A. swirskii showed preference for both cultivars RM and MA compared to EE. These experiments indicated that the number of tuft domatia and availability of pollen can influence the host preference of A. swirskii for an ornamental pepper banker plant cultivar. Results from this study will help growers, researchers, educators and extension personnel in understanding the plant phenology promoting adoption of suitable banker plants for managing greenhouse and landscape insect pests. 相似文献
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A universal procedure for controlling the sylphon hermeticity is discussed. Travelling sylphon or membrane diaphragms in combination with a dublicate sylphon are used as a separating element at the border of the separating media, e. g. the medium transporting through the valve and the environmental air. Pneumatic pressure higher than the working pressure of the separating medium is created inside the space between the working and the dublicate sylphons. If the hermeticity of one of the above sylphons is broken, the excessive pressure inside the space between them is reduced which is automatically stated by means of a pneumatic probe. Because of detection of the breach in the hermeticity of one of the sylphons in proper time, when the second sylphon is safe, the contact of the transporting medium with the environmental air is prevented. The described procedure for controlling the hermeticity is universal since it provides the use of the probes working only under the pressure independent of the type and physico-chemical properties of the separating medium. One of the important advantages of the new procedure is also the fact that the working sylphon appears to be empty since the outer with respect to it pressure of the separating medium is practically balanced by the pressure created in the sylphon space. 相似文献
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The influence of pollen on combining predators to control Frankliniella occidentalis in ornamental chrysanthemum crops 总被引:3,自引:0,他引:3
David Skirvin Lidija Kravar-Garde Kelly. Reynolds Julie Jones Michael De Courcy Williams 《Biocontrol Science and Technology》2006,16(1):99-105
Small scale glasshouse trials showed that second instar nymphs of Orius laevigatus reduced Frankliniella occidentalis numbers (78-92%) more than Neoseiulus cucumeris (0-30%). Combining the predators did not increase reduction of thrips numbers (84-93%). Pollen did not increase thrips control, but led to an increase in the number of thrips. 相似文献
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An investigation of live or freshly prepared feeds used as maturationdiets for freshwater ornamental fish was conducted to uncover similaritiesor differences in total and essential fatty acids. Analysis of these maturation feeds reveals that there are relatively low levels of totalfatty acids (0.81–8.96 mg/100 mg–1 dry weight) and withthe exception of the beef heart diet all other feeds have undetectablelevels of docosahexaenoate (22:6n3). The beef heart diet was observed topossess 4.86 mg 100 mg–1 dry weight of 22:6n3 most probablydue to the addition of skipjack tuna, Katsuwanus pelamis, roe. All otherfeeds examined were found to contain low to moderate levels ofeicosapentaenoate (20:5n3) 0.00–0.61 mg/100 mg–1 dryweight. Surprisingly relatively high amounts of arachidonate (20:4n6)0.16–0.90 mg/100 mg–1 dry weight were observed in all ofthe maturation diets and ranged between 3.79%–27.16% ona percent composition basis. The results obtained to date indicate a need toscrutinize the role of arachidonate in the maturation and spawningprocess. 相似文献
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Summary Greenhouse and field experiments were conducted on the effect of VA mycorrhiza (VAM) on the growth of cassava, various tropical
grass and legume species, as well as beans, coffee and tea. A large number of VAM fungal species were evaluated for effectivity
in increasing cassava growth and P uptake in acid low-P soils. The effectivity of VAM species and isolates was highly variable
and dependent on soil pH and fertilizer applications, as well as on soil temperature and humidity. Two species,Glomus manihotis andEntrophospora colombiana were found to be most effective for a range of crops and pastures, at low pH and at a wide range of N, P, and K levels.
At very low P levels nearly all crops and pasture species were highly mycorrhizal dependent, but at higher soil P levels cassava
and several pasture legumes were more dependent than grass species.
Mycorrhizal inoculation significantly increased cassava and bean yields in those soils with low or ineffective indigenous
mycorrhizal populations. In these soils cassava root yields increased on the average 20–25% by VAM inoculation, both at the
experiment station and in farmers’ fields. VAM inoculation of various pasture legumes and grasses, in combination with rock
phosphate applications, increased their early growth and establishment. Agronomic practices such as fertilization, crop rotations,
intercropping and pesticide applications were found to affect both the total VAM population as well as its species composition.
While there is no doubt about the importance of VA mycorrhiza in enhancing P uptake and growth of many tropical crops and
pastures grown on low-P soils, much more research is required to elucidate the complicated soil-plant-VAM interactions and
to increase yields through improved mycorrhizal efficiency. 相似文献
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In previous glasshouse experiments, the soilbacterium Serratia plymuthica, strainA153, showed strong growth-suppressingactivities against a range of broad-leavedweeds after foliar spraying. In field tests ofthis strain in spring wheat, spring barley andpotatoes, variable effects were achieved on arange of weeds including Chenopodiumalbum, Stellaria media, Polygonumconvolvulus and Galeopsis speciosa. Atone site, good suppression of C. albumwas observed when the strain was applied in atank mix with another bacterial isolate or withreduced doses of a herbicide. Effects on weedsappeared to be independent of the applicationvolume (1000, 600, 500 l ha–1), but weedswere in some cases more strongly suppressed athigher bacterial doses. Barley yields weresomewhat reduced by the bacterial application,but wheat yields were less affected. AlthoughS. plymuthica suppressed certain weedswhen applied in the field in a simple aqueousformulation and with conventional sprayingequipment, the level of weed suppression wasunsatisfactory from a practical standpoint. 相似文献
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Knowledge of inter and intra-specific variation in the susceptibility of natural enemies to pesticides could help to better design integrated pest management strategies. The objective of this research was to evaluate the susceptibility to deltamethrin in populations of the predatory mites Neoseiulus californicus (McGregor) and Phytoseiulus macropilis (Banks) populations collected from protected ornamental crops in Brazil. The susceptibility to deltamethrin was characterized against immature and adult stages of both species. The impact of this insecticide was also measured by estimating the intrinsic rate of increase (r i). The immature and adult stages of N. californicus were approximately 3,600 and 3,000-fold more tolerant to deltamethrin than those of P. macropilis. However, high variability in the susceptibility to this insecticide was detected among P. macropilis populations, with resistance ratios of up to 3,500-fold. The selection of deltamethrin-resistant strains of P. macropilis could be exploited in applied biological control programs. 相似文献
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Risk assessment for engineered bacteria used in biocontrol of fungal disease in agricultural crops 总被引:1,自引:0,他引:1
A plant growth promoting rhizobacterium (PGPR)Pseudomonas fluorescens SBW25 (WT) protects a number of crop plant species from damping-off caused by Pythium ultimum. A genetically modified, phenazine-1-carboxylic acid (PCA) producing variant, 23.10, carries on its chromosome a single copy
of phzABCDEFG, under the control of the P tac constitutive promoter. The genetically modified biological control agent (GM-BCA), 23.10, has improved biocontrol activity
when compared to wild type SBW25, and can effectively suppress Pythium spp. present at up to 100 times normal field infestations. GM-BCA inocula establish high population densities which persist
well in the phytosphere of several crop plants including pea, wheat and sugar beet, effectively suppressed infection and promoted
increase in total plant biomass. It also has an improved spectrum of activity over other plant phytopathogens such as Fusarium spp. Gaeumannomyces graminis var. tritici, Phytophtora cinnamomi and Rhizoctonia solani. However in developing BCAs and in particular GMBCAs it is important to determine whether their use has any adverse effect
in the environment. Any observed changes following inoculation with wild type BCA or GM BCA in microbial diversity (bacteria
and fungi) were negligible when assessed by either quantitive selective plate count methods (CFU/g) or culture independent
molecular assays (SSU rRNA based PCR-DGGE). Rhizosphere community diversity profiles (DGGE) in infected plants in the presence
of inocula were highly similar to disease free systems. Histological assessment of the impact of inocula on established functional
mycorrhizae associations were conducted on cores collected from an established field margin grassland pasture. No adverse
impact on mycorrhizal colonization and root infection were recorded after addition of WT or GM-BCA bacterial inocula as a
soil drench. This approach and the related culturable and culture independent methods have recorded only a minor, transient
perturbation to microbial communities, but as far as we are aware this is the first direct demonstration that a functional,
AFC producing GMM also has only a transient impact on mycorrhizal associations in established plant communities. In all instances
studied the plant species, plant stage of development and disease, damping-off, had a greater impact on changes in rhizosphere
diversity than the presence of an introduced GM bacterial inocula. 相似文献
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We survey cloning vehicles whose function is to carry and express a gene in host cells including Escherichia coli, Saccharomyces cerevisiae and mammalian cells. In E. coli these include vehicles based on the lac operon, the trp operon, the rho leftward operon, and the recA gone; open reading frame cloning vehicles are also discussed, as are steps that can be taken to extrude a gene product from the cell and the use of plasmids with runaway replication. In S. cerevisiae we discuss vehicles based on the PGK gene, the ADH1 gene, the acid phosphatase gene and the GAL1-GAL10 gene cluster. In mammalian cells we discuss vehicles based on SV40 promoters, the metallothionein gene, retroviral LTR promoters, bovine papilloma virus and vaccinia virus. 相似文献
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化学交联技术在蛋白质相互作用研究中的应用 总被引:1,自引:0,他引:1
蛋白质相互作用是生命科学研究的一个重要领域.随着生物质谱的出现,利用化学交联技术研究蛋白质的相互作用已经成为切实可行的策略.文章介绍了化学交联反应的相关内容,及其在蛋白质相互作用研究中的应用,并简单探讨了甲醛作为交联剂的应用价值. 相似文献
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Characterization of fungi isolated from the equipment used in the International Space Station or Space Shuttle 下载免费PDF全文
Kazuo Satoh Takashi Yamazaki Takako Nakayama Yoshiko Umeda Mohamed Mahdi Alshahni Miho Makimura Koichi Makimura 《Microbiology and immunology》2016,60(5):295-302
As a part of a series of studies regarding the microbial biota in manned space environments, fungi were isolated from six pieces of equipment recovered from the Japanese Experimental Module “KIBO” of the International Space Station and from a space shuttle. Thirty‐seven strains of fungi were isolated, identified and investigated with regard to morphological phenotypes and antifungal susceptibilities. The variety of fungi isolated in this study was similar to that of several previous reports. The dominant species belonged to the genera Penicillium, Aspergillus and Cladosporium, which are potential causative agents of allergy and opportunistic infections. The morphological phenotypes and antifungal susceptibilities of the strains isolated from space environments were not significantly different from those of reference strains on Earth. 相似文献
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Interaction between Podisus maculiventris and Harmonia axyridis two predators used in augmentative biological control in greenhouse crops 总被引:2,自引:3,他引:2
Intraguild predation (IGP) betweenthe pentatomid Podisus maculiventris(Say) and the coccinellid Harmoniaaxyridis (Pallas) in the absence or presenceof the extraguild prey Spodopteralittoralis (Boisduval) and Myzuspersicae (Sulzer) was studied in thelaboratory. Interactions were asymmetric infavor of the pentatomid. Podisusmaculiventris readily fed upon eggs and larvaeof H. axyridis, but adult beetles wererarely attacked. Success of attacks by P.maculiventris was stage dependent, fourthinstars and adults being more successful inkilling ladybeetle larvae than second instars.Attacks by H. axyridis on the pentatomidwere rare and none of them were successful. Theeffect of introducing extraguild prey on thelevel of IGP was tested both in petri dishesand on caged sweet pepper plants. Whensufficient numbers of S. littoralislarvae were present to satiate the pentatomid,predation on H. axyridis larvae decreasedsignificantly, indicating that the coccinellidis a less preferred or less vulnerable prey.When the aphid M. persicae was presentedas extraguild prey, levels of IGP were notaltered. Nymphs of P. maculiventrissuccessfully completed development whenexclusively fed on larvae of H. axyridis,but developmental time was longer than onlepidopteran prey. No pentatomid nymphs reachedadulthood on aphids alone. IGP by P.maculiventris on H. axyridis may be ofsome importance in greenhouse crops, where bothpredators are being used increasingly inaugmentative biological control programs.Nonetheless, it is expected that in practicelarger larvae and adults of H. axyridiswill escape most attacks by the pentatomid. 相似文献
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T. Funda M. Lstibůrek P. Lachout J. Klápště Y. A. El-Kassaby 《Tree Genetics & Genomes》2009,5(4):583-593
Genetic gain and diversity of seed orchards’ crops are determined by the number of parents, their breeding values and relatedness,
within-orchard pollination efficiency, and level of pollen contamination. These parameters can be manipulated at establishment
by varying clonal representation (e.g., linear deployment), during orchard development by genetic thinning, or by selective
harvesting. Since clonal fecundities are known to vary both within and among years, then each seed crop has a unique genetic
composition and, therefore, crops should be treated on a yearly basis. Here we present an optimization protocol that maximizes
crop’s genetic gain at any desired genetic diversity through the selection of a subset of the crop that meets both parameters.
The genetic gain is maximized within the biological limit set by each clone’s seed-cone production and effective population
size is used as a proxy to genetic diversity whereby any relationship among clones is considered. The optimization was illustrated
using 3 years’ reproductive output data from a first-generation western larch seed orchard and was tested under various scenarios
including actual male and female reproductive output and male reproductive output assumed to be either equal to that of female
or a function of clonal representation. Furthermore, various levels of co-ancestry were assigned to the orchard’s clones in
supplementary simulations. Following the optimization, all solutions were effective in creating custom seedlots with different
gain and diversity levels and provided the means to estimate the genetic properties of composite seedlots encompassing the
remaining “unused” seed from a number of years. 相似文献