scholarly journals First Report on the Diversity of Epizoic Algae in Larval of Shellfish Gastropod Aliger gigas

2021 ◽  
Author(s):  
Rocío Elizabeth Muciño-Márquez ◽  
Dalila Aldana-Aranda ◽  
María Guadalupe Figueroa-Torres ◽  
Oscar Hernández-Almeida
Keyword(s):  
Electron Microscopy ◽  
Egg Masses ◽  
First Report ◽  
Gastropod Mollusk ◽  
Marine Crustaceans ◽  
Frequent Species ◽  
Algal Material ◽  
Identification And Quantification

Epibiosis occur frequently on the shells of some marine crustaceans, which often serve as substrate for various species of algae, there is few information on the associations between these. The objective of this study was to determine if the gastropod mollusk Aliger gigas (formerly Lobatus gigas) in larval had some sort of the association with algal. To the above was carried out collecting egg masses in the environment, the larvae were cultivated in seawater filtered 5 μm. The algal material found was observed in electron microscopy, for its identification and quantification. We analyzed 60 larvae aged 2–44 days for analyzing the structure of the shell and its epibionts. Of the larvae analyzed, 50 larvae presented epizoic. The algae community consisted of 28 taxa, and composed of 25 diatoms (Bacillariophyta) and three cyanophytes (Cyanobacteria). The H´ diversity values fluctuated between 0.2 a 1.2. The dominant and frequent species were formed by diatoms: Nitzschia panduriformis var. minor, Halamphora sp. and Cyclophora sp.

Light-insulating apparatus of the camera-like eye of the terrestrial gastropod mollusk Arion rufus (Heterobranchia, Stylommatophora)

2021 ◽  
Vol 31 (1) ◽  
pp. 39-49
Author(s):  
I. P. Shepeleva
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Photoreceptor Cells ◽  
Cellular Composition ◽  
Gastropod Mollusk ◽  
Evolutionary Changes ◽  
Pulmonate Mollusk ◽  
Arion Rufus ◽  
Terrestrial Gastropod

The cellular composition, the morphology of the components, and the screening function and evolutionary changes of the light-insulating apparatus of the camera-like eye of the terrestrial gastropod pulmonate mollusk Arion rufus were studied and evaluated using light and electron microscopy. According to all the considered characteristics, the light-insulating apparatus of A. rufus is typical for terrestrial pulmonate mollusks. Evolutionary transformations of the light-insulating apparatus, caused by the change in the mollusks' environment, are insignificant and affect the cellular composition, the morphology of pigmented cells and the isolation of the light-sensitive parts of photoreceptor cells from each other.

scholarly journals First Report of Meloidogyne partityla on Pecan in New Mexico

Plant Disease ◽  
2001 ◽  
Vol 85 (9) ◽  
pp. 1030-1030 ◽  
Author(s):  
S. H. Thomas ◽  
J. M. Fuchs ◽  
Z. A. Handoo
Keyword(s):  
New Mexico ◽  
The United States ◽  
Root Knot Nematode ◽  
Carya Illinoensis ◽  
Morphological Examination ◽  
Egg Masses ◽  
First Report ◽  
Additional Information ◽  
Dona Ana County ◽  
Normal Fertilization

For several years, decline was observed in mature pecan (Carya illinoensis (F.A. Wangenheim) K. Koch) trees in an orchard in Dona Ana County, New Mexico despite normal fertilization and irrigation practices. Affected trees were growing in sandy soil in two widely separated irrigation terraces and exhibited chlorosis of foliage and substantial die-back of branches in the upper canopy. Examination of feeder roots revealed the presence of numerous small galls and egg masses, with root-knot nematode females often visibly protruding from root tissue. Attempts to culture the nematode on tomato (Lycopersicon esculentum Mill. ‘Rutgers’) were unsuccessful. Females and egg masses were collected from fresh pecan roots and sent to the USDA Nematology Laboratory in Beltsville, MD, in October 2000, where specimens were identified as Meloidogyne partityla Kleynhans (1) based on morphological examination. This is the first report of M. partityla from New Mexico, and the second report of this nematode outside South Africa. Starr et al. (2) first reported M. partityla from pecan in the United States in 1996, after recovering the nematode from five orchards in Texas. In their study, the host range of M. partityla was limited to members of the Juglandaceae, which may explain the inability of the New Mexico population to reproduce on tomato. Additional information is needed regarding distribution of this nematode within pecan-growing regions throughout North America. References: (1) K. P. N. Kleynhans. Phytophylactica 18:103, 1986. (2) J. L. Starr et al. J. Nematol. 28:565, 1996.

scholarly journals First Report of a Carlavirus in Fuchsia spp. in New Zealand

Plant Disease ◽  
2011 ◽  
Vol 95 (11) ◽  
pp. 1484-1484 ◽  
Author(s):  
Z. Perez-Egusquiza ◽  
L. W. Liefting ◽  
S. Veerakone ◽  
G. R. G. Clover ◽  
M. Ciuffo
Keyword(s):  
Electron Microscopy ◽  
New Zealand ◽  
Coat Protein ◽  
Chenopodium Quinoa ◽  
Plant Diseases ◽  
Nucleotide Identity ◽  
Impatiens Necrotic Spot Virus ◽  
Rt Pcr ◽  
First Report ◽  
Genome Region

The genus Fuchsia has 110 known species and numerous hybrids. These ornamental plants with brightly colored flowers originate from Central and South America, New Zealand, and Tahiti, but a wider variety are now grown all over the world. Few viruses have been reported in Fuchsia spp.: a carlavirus, Fuchsia latent virus (FLV) (1–3), a cucumovirus, Cucumber mosaic virus (CMV) (3), and two tospoviruses, Impatiens necrotic spot virus (INSV) and Tomato spotted wilt virus (TSWV) (4). In August 2009, five plants, each representing a different cultivar of Fuchsia hybrid, from home gardens in the Auckland and Southland regions of New Zealand, displayed variable symptoms including mild chlorosis, mild mottle, or purple spots on leaves. Plants tested negative for CMV, INSV, and TSWV using commercial ImmunoStrips (Agdia Inc., Elkhart, IN); however, flexuous particles of ~650 to 700 nm were found by electron microscopy in all samples. Local lesions were also observed on Chenopodium quinoa plants 4 weeks after sap inoculation. Total RNA was extracted from all plants with a RNeasy Plant Mini Kit (Qiagen Inc., Doncaster, Australia) and tested by reverse transcription (RT)-PCR using two generic sets of primers (R. van der Vlugt, personal communication) designed to amplify fragments of ~730 and 550 bp of the replicase and coat protein genes of carlaviruses, respectively. Amplicons of the expected size were obtained for all samples, cloned, and at least three clones per sample were sequenced. No differences within clones from the same samples were observed (GenBank Accession Nos. HQ197672 to HQ197681). A BLASTn search of the viral replicase fragment showed the highest nucleotide identity (76%) to Potato rough dwarf virus (PRDV) (EU020009), whereas the coat protein fragment had maximum nucleotide identity (70 to 72%) to PRDV (EU020009 and DQ640311) and Potato virus P (DQ516055). Sequences obtained were also pairwise aligned using the MegAlign program (DNASTAR, Inc., Madison, WI) and results showed that the isolates had 83 to 97% identity to each other within each genome region. Further sequences (HQ197925 and HQ197926) were obtained from a Fuchsia plant originating from Belgium, a BLASTn analysis showed high nucleotide identity (84 to 99%) to the New Zealand isolates. The low genetic identity to other Carlavirus members suggests that these isolates belong to a different species from those previously sequenced. On the basis of electron microscopy and herbaceous indexing, the isolates had similar characteristics to a carlavirus reported from Fuchsia in Italy (1) and FLV reported in Canada (2). The Italian carlavirus isolate was obtained and tested with the same primers by RT-PCR. Pairwise analysis of the Italian sequences (HQ197927 and HQ197928) with the New Zealand and Belgian sequences showed between 84 and 95% similarity within each genome region. These results suggest that the carlavirus infecting these plants is the same virus, possibly FLV. To our knowledge, this is the first report of this carlavirus infecting Fuchsia spp. in New Zealand, but the virus has probably been present for some time in this country and is likely to be distributed worldwide. References: (1) G. Dellavalle et al. Acta Hortic. 432:332, 1996. (2) L. J. John et al. Acta Hortic. 110:195, 1980. (3) P. Roggero et al. Plant Pathol. 49:802, 2000. (4) R. Wick and B. Dicklow. Diseases in Fuchsia. Common Names of Plant Diseases. Online publication. The American Phytopathological Society, St. Paul, MN, 1999.

scholarly journals First Report of Xylella fastidiosa Infecting Citrus in Costa Rica

Plant Disease ◽  
2005 ◽  
Vol 89 (6) ◽  
pp. 687-687 ◽  
Author(s):  
E. Aguilar ◽  
W. Villalobos ◽  
L. Moreira ◽  
C. M. Rodríguez ◽  
E. W. Kitajima ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Costa Rica ◽  
Sweet Orange ◽  
Enzyme Linked Immunosorbent Assay ◽  
Negative Bacterium ◽  
Gram Negative ◽  
First Report ◽  
Leaf Petiole ◽  
Orange Trees ◽  
Das Elisa

Citrus variegated chlorosis (CVC) is an important disease mainly of sweet orange (Citrus sinensis (L.) Osbeck) cultivars. It was first described in Brazil in the state of Sā Paulo in 1987 (4). The disease has spread to all Brazilian states that grow citrus and is affecting more than one-third of the orange trees grown in Brazil. CVC is caused by Xylella fastidiousa, a xylem-limited, gram-negative bacterium. During the last 4 years, symptoms including leaf interveinal chlorosis, stunting, canopy dieback, and hard and undersized fruits, similar to those caused by CVC (3), appeared in sweet orange trees used as shade plants for coffee plantations and as fence posts in Costa Rica. Necrotic lesions on the abaxial side of the leaves as reported in Brazil were rarely observed. Leaf petiole samples from 25 symptomatic sweet orange trees reacted positively with a X fastidiosa-specific antiserum (AGDIA Inc., Elkart, IN) in a double-sandwich antibody enzyme-linked immunosorbent assay (DAS-ELISA). A fastidious, gram-negative bacterium identified as X. fastidiosa using DAS-ELISA was isolated on perwinkle wilt (PW) medium plates (1) from citrus stems showing CVC symptoms, but not from asymptomatic trees. The isolated colonies were circular and opalescent with diameters of 2 to 3 mm and were clearly visible within 6 to 7 days after streaking. Petiole sections from symptomatic plants observed with scanning electron microscopy showed rod-shaped bacteria with rippled cell walls tightly packed in xylem vessels, as described for X. fastidiosa previously (2), and with transmission electron microscopy, the bacteria were morphologically similar to those reported previously for CVC (2). To our knowledge, this is the first report of X. fastidiosa associated with citrus in Costa Rica. References: (1) M. J. Davis et al. Curr. Microbiol. 6:309, 1981. (2) J. S. Hartung et al. Phytopathology 84:591, 1994. (3) R. F. Lee et al. Summa Phytopathol. 19:123, 1993. (4) V. Rossetti et al. 1990, C.R. Acad. Sci. (Paris) 310:345–349.

scholarly journals First Report of Blueberry red ringspot virus Infecting Highbush Blueberry in Korea

Plant Disease ◽  
2012 ◽  
Vol 96 (7) ◽  
pp. 1074-1074 ◽  
Author(s):  
I. S. Cho ◽  
B. N. Chung ◽  
J. D. Cho ◽  
G. S. Choi ◽  
H. S. Lim
Keyword(s):  
Electron Microscopy ◽  
Nucleotide Sequence ◽  
Coat Protein ◽  
Reverse Transcriptase ◽  
Nucleotide Sequence Identity ◽  
Ringspot Virus ◽  
Highbush Blueberry ◽  
First Report ◽  
Sequence Identity ◽  
Symptomatic Plant

Blueberry red ringspot virus (BRRSV) of the Soymovirus genus in the family Caulimovididae causes red ringspot diseases in highbush blueberry (Vaccinium corymbosum L.) on leaves, stems, and fruits. The virus has been identified in the United States, Japan, Czech Republic, Slovenia, and Poland (1). In July 2010, highbush blueberry with red ringspots on leaves and circular blotches on ripening fruits was found in one plant of cv. Duke in Pyeongtaek, Korea. The symptoms were similar to red ringspot disease caused by BRRSV (3), although stems did not show any characteristic symptoms. Red ringspots on the upper surface of leaves were the most visible symptom and became more prominent as leaves matured in August through October. Leaves of the symptomatic plant were collected and tested for BRRSV infection by PCR, and were also embedded for electron microscopy. DNA was extracted from leaves using DNeasy Plant Mini Kit (Qiagen, Valencia, CA) according to the manufacturer's instructions. Primer pairs BR1512F/BR2377R (5′-ACAGGACGATTAGAAGATGG-3′/5′-CCTTTAGGGCAATATTTCTG-3′, amplifying a fragment of the coat protein region with an expected size of 865 bp) and BR2961F/BR3726R (5′-ACCGATACATCACAGTTCAC-3′/5′-TGGTTGTGATAAGATGATTCC-3′, amplifying a fragment of the reverse transcriptase region with an expected size of 766 bp) were used to amplify the indicated region of BRRV in PCR. Primers were designed on the basis of the BRRSV isolate from New Jersey (GenBank Accession No. AF404509). DNA fragments of the expected sizes were obtained from the symptomatic plant, while no amplification products were obtained from highbush blueberry without symptoms. The PCR products were cloned into pGEM-T easy vector (Promega, Madison, WI) and sequenced. BLAST analyses of obtained fragments revealed 91 to 98% nucleotide sequence identity with the coat protein gene (GenBank Accession No. JQ706341) and 96 to 98% nucleotide sequence identity with the reverse transcriptase gene (GenBank Accession No. JQ706340) of known BRRV isolates. Electron microscopy of thin sections revealed particles approximately 50 nm diameter within electron-dense inclusion bodies, characteristic of BRRSV (2) To our knowledge, this is the first report of BRRSV infection of highbush blueberry in Korea. Highbush blueberries are usually propagated by cutting, so BRRSV suspicious plants should be tested with PCR before they are propagated. References: (1) E. Kalinowska et al. Virus Genes. DOI 10.1007/s11262-011-0679-4, 2011. (2) K. S. Kim et al. Phytopathology 71:673, 1981. (3) M. Isogai et al. J. Gen. Plant Pathol. 75:140, 2009.

scholarly journals First Report of Meloidogyne marylandi Infecting Bermudagrass in Oklahoma

Plant Disease ◽  
2014 ◽  
Vol 98 (9) ◽  
pp. 1286-1286 ◽  
Author(s):  
N. Walker
Keyword(s):  
Cynodon Dactylon ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Similar Species ◽  
Root Knot Nematode ◽  
Putting Greens ◽  
Egg Masses ◽  
First Report ◽  
Mean Width ◽  
Ultradwarf Bermudagrass

Meloidogyne marylandi is a nematode commonly associated with turfgrasses and has been reported to occur in Texas and Arkansas (1,3). In the fall of 2013, a stand of ultradwarf bermudagrass (Cynodon dactylon × C. transvaalensis) plants in a sand-based, research putting green in Stillwater, Oklahoma, exhibited symptoms of decline. Roots of the affected plants had small galls and upon staining of the root system, numerous egg masses were evident. Egg masses were collected, placed in water, and the morphology of 20 hatched, second-stage juveniles were examined. The characteristics of the juveniles were: body length averaged 393.1 ± 19.87 (range: 361 to 425) μm, mean width averaged 16.6 ± 0.7 (15.6 to 17.8) μm, stylet lengths averaged 12.1 ± 0.7 (10.4 to 12.9) μm, dorsal gland orifice from stylet base averaged 2.9 ± 0.4 (2.5 to 3.6) μm, tail lengths averaged 53.7 ± 3.8 (46.2 to 60.4) μm, and the hyaline region of the tails averaged 10.4 ± 1.1 (8.4 to 12.7) μm. Genomic DNA was extracted from six females that were removed from roots. Amplification and sequencing of the mitochondrial DNA region between COII and 16S rRNA genes was performed with primers 1RNAF (5′-TACCTTTGACCAATCACGCT-3′) and CO11R (5′-GGTCAATGTTCAGAAATTTGTGG-3′) as previously described (2). A PCR product approximately 510 bp in length was obtained and sequenced at the Oklahoma State University Core Facility. Sequences were compared with those in NCBI's nucleotide database using BLAST and had 97% identity with two sequences from M. marylandi (KC473862.1 and KC473863.1) and the next most similar species being M. graminis (JN241898.1) with 83% identity. To our knowledge, this is the first report of the root-knot nematode M. marylandi in Oklahoma. As bermudagrass becomes more commonly used for putting greens in the turfgrass transition zone, M. marylandi may become a more common and damaging pathogen in the region. References: (1) A. A. Elmi et al. Grass For. Sci. 55:166, 2000. (2) M. A. McClure et al. Plant Dis. 96:635, 2012. (3) J. L. Starr et al. Nematrop. 37:43, 2007.

scholarly journals Ovipositional Behavior of the Egg Parasitoid Gryon pennsylvanicum (Hymenoptera: Scelionidae) on Two Squash Bug Species Anasa tristis (Hemiptera: Coreidae) and Anasa armigera: Effects of Parasitoid Density, Nutrition, and Host Egg Chorion on Parasitism Rates

2020 ◽  
Vol 49 (6) ◽  
pp. 1307-1315
Author(s):  
Mary L Cornelius ◽  
Bryan T Vinyard ◽  
Joseph D Mowery ◽  
Jing S Hu
Keyword(s):  
Electron Microscopy ◽  
Laboratory Tests ◽  
Egg Parasitoid ◽  
Egg Masses ◽  
Anasa Tristis ◽  
Ovipositional Behavior ◽  
Squash Bug ◽  
Percent Parasitism ◽  
Transmission Electron ◽  
Parasitism Rates

Abstract This study examined the ovipositional behavior of Gryon pennsylvanicum Ashmead (Hymenoptera: Scelionidae) on egg masses of two squash bug species Anasa tristis DeGeer and Anasa armigera Say (Hemiptera: Coreidae) by evaluating how parasitoid density and access to nutrition influenced percent parasitism on egg masses of different sizes in laboratory tests. When three parasitoids were exposed to A. tristis egg masses with only three to five eggs, 72.7% of parasitoids became trapped in the eggs and failed to emerge successfully. These results suggest that competition between larvae within the egg may have reduced the fitness of the surviving parasitoid. Continual access to honey water did not significantly influence parasitism rates on A. armigera egg masses and only increased parasitism on A. tristis egg masses with 20–25 eggs. Overall, parasitism rates were higher on A. armigera egg masses than on A. tristis egg masses, and parasitoids were more likely to emerge successfully from A. armigera eggs than from A. tristis eggs. Parasitoids spent the same amount of time probing eggs of the two species, but they spent significantly more time drilling into A. tristis eggs than A. armigera eggs. Measurements taken using transmission electron microscopy determined that the average combined width of the epicuticle and exocuticle of the egg chorion was significantly greater for A. tristis eggs than for A. armigera eggs. This difference may account for the lower rates of parasitism and parasitoid emergence and for the increased time spent drilling into A. tristis eggs compared with A. armigera eggs.

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