scholarly journals The Whitefly Dialeurodes citri: A New Pest on Citrus in Tunisia?

2021 ◽  
Vol 16 (1) ◽  
pp. 11-18
Author(s):  
Synda Boulahia-Kheder ◽  
Keyword(s):  
Common Species ◽  
Biological Traits ◽  
Severe Damage ◽  
Control Programs ◽  
North East ◽  
Dialeurodes Citri ◽  
Citrus Orchards ◽  
Parabemisia Myricae ◽  
Very High ◽  
New Pest

Whiteflies invaded citrus orchards in Tunisia in the 90’s. Two species: Aleurothixus floccosus and Parabemisia myricae have been recorded successively infesting citrus and causing severe damage in Cap-Bon (North-East of Tunisia). These pests were first controlled by several insecticidal applications but with a relative efficiency. Then two biological control programs have been deployed completing the action of native natural enemies especially for P. myricae. The result was a very satisfactory control of both whitefly species, to a point that they almost disappeared from orchards for about 30 years. In 2017, a third whitefly species, identified as Dialeurodes citri, was observed during a prospection in citrus orchards in Takelsa region (Cap-Bon). It was a common species in Algeria, but never caused damage in Tunisia. In 2020, D. citri was found again with very high population densities in the regions of Menzel Bou Zelfa (Cap-Bon) and Tunis. These observations confirmed its change of status and spread in Tunisia. The main morphological and biological traits to distinguish between D. citri and the other two whitefly species, already recorded in Tunisia, were described and first observations on its infestation were reported. Some recommendations to manage this new pest are given.

Diversity of the Cyanoprokaryota in polar deserts of Innvika cove North-East Land (Nordaustlandet) Island, Spitsbergen

2016 ◽  
Vol 6 (1) ◽  
pp. 66-79 ◽  
Author(s):  
Denis Davydov
Keyword(s):  
Common Species ◽  
Southern Coast ◽  
Nostoc Commune ◽  
The West ◽  
North East ◽  
West Part ◽  
Wet Rocks ◽  
First Time ◽  
Very High ◽  
Sørensen Index

The study of polar deserts cyanoprokaryotes up to now is few. Foremost this is connected with difficulty visiting of the area. The paper presents the results of a study of сyanoprokaryota on the southern coast of Innvika cove (Fotherbyfjorden bay, North-East Land Island, Spitsbergen archipelago). A total of 74 taxa were observed in various habitats of investigated area. Nine species are reported for the first time for Spitsbergen flora. Gloeocapsopsis magma (20 observations), Nostoc commune (19), Microcoleus autumnalis (17) were the most common species in the investigated samples. The most number of species (42) was found on wet rocks. The similarity Sorensen index between wet rock species, seepage species and pools species is very high. It can mean that for many species the only necessary preference in habitat is a rock substrate and wetting. Most similar are the flora of the Innvika area and flora of the west part of Oscar II Land (61%).

CLINICALAND MYCOLOGICAL PROFILE OF ONYCHOMYCOSIS IN A HILLY STATE OF NORTH - EAST INDIA .

2021 ◽  
pp. 41-43
Author(s):  
Subrata kumar Das ◽  
Saptadipa Das
Keyword(s):  
Epidemiological Data ◽  
Common Species ◽  
Term Treatment ◽  
Predisposing Factor ◽  
Cross Sectional ◽  
Diagnostic Strategies ◽  
North East India ◽  
North East ◽  
Number Of Patients ◽  
Long Term Treatment

Background: Onychomycosis is a chronic fungal infection of nger nails and toe nails. It is a non life threatening condition and requires long-term treatment. Mostly patients seek medical care for cosmetic purpose unless it gets secondarily infected and produce pain. Aims: The aim of this study was to determine the prevalence of various causative agents of onychomycosis and to study the clinical and mycological patterns of onychomycosis . Material and Methods: This was a cross sectional observational study which was carried over a period of one year , from December 2019 to November 2020 . A total of 47 patients were included in the study , who visited Dermatology OPD of SMIMS , Sikkim, India. After clinical evaluation , nail samples were subjected for KOH mount and culture. Results:This study included 47 patients of clinically diagnosed onychomycosis , 30 males and 17 males . In the present study maximum number of patients belonged to the age group 30-40 years with 28 patients . Most of the study subjects , 22 were agricultural worker . We found that trauma to the nails was the commonest predisposing factor 17. Out of 47 patients 33 patients were KOH positive and 21 patients were culture positive. Most common type of onychomycosis was Distal lateral subungual onychomycosis with 2 cases . Most common species identied in our study was T.rubram with 5 patients , followed by T. mentagrophytes with 3 patients. Conclusion: Along dermatophytes , NDM and yeasts were also common aetiological agents of onychomycosis. Since onychomycosis can cause physical , psychological and occupational problems, the clinico-epidemiological data can be helpful in development of preventive and diagnostic strategies.

INFESTIBILITY OF OILSEEDS, CLOVER, AND MILLET BY STORED-PRODUCT INSECTS

1972 ◽  
Vol 52 (4) ◽  
pp. 431-440 ◽  
Author(s):  
R. N. SINHA
Keyword(s):  
Tribolium Castaneum ◽  
Common Species ◽  
Western Canada ◽  
Cryptolestes Ferrugineus ◽  
Potential Danger ◽  
Complete Development ◽  
Stored Product Insects ◽  
Oryzaephilus Mercator ◽  
Insect Attack ◽  
New Pest

Infestation potential of 16 cultivars of flax, mustard, rape, sunflower, millet, and clover seeds to five common species of stored-product insects was determined. When multiplication was used as a criterion, whole seeds were resistant to insect attack although minor infestation occurred on certain cultivars. Although some species of insects could complete development on certain cultivars, few could reproduce well on clover and mustard cultivars. Oilseeds were more susceptible to Oryzaephilus mercator than to any other insect species. Cryptolestes ferrugineus, which thrived on the millet cultivars Crown and Siberian, neither reproduced nor completed development on any of the oilseed and forage cultivars. All cultivars of crushed Noralta, Raja, and Redwood flax were susceptible to: O. mercator, O. surinamensis, and Tribolium castaneum; Echo and Target rape only to O. mercator; Armavirec, Krasnodarets, Mennonite, and Peredovic sunflowers to all insects except C. ferrugineus; and Crown and Siberian millet to all insects. Tribolium confusum reproduced only on sunflower and millet cultivars. The potential danger of stored oilseeds in Western Canada from a new pest, O. mercator, was evaluated.

The effect of seed rate and nitrogen fertilizer on the yield and nutritive value of oat-vetch mixtures

1989 ◽  
Vol 112 (1) ◽  
pp. 57-66 ◽  
Author(s):  
N. Moreira
Keyword(s):  
Nitrogen Fertilizer ◽  
Crude Protein ◽  
Nutritive Value ◽  
High Yield ◽  
Mineral Nutrient ◽  
Yield Response ◽  
N Nutrition ◽  
North East ◽  
Positive Effect ◽  
Very High

SummaryExperiments were conducted on the seed rates of the components of oat-vetch mixtures combined with varying rates of nitrogen fertilizer in a rainfed area of north-east Portugal in 1982–3 and 1984–5.Forage oats grown alone showed a very high yield response to N and rainfall ranging from 30 to 18·2 t D.M./ha, but had a very low crude protein concentration (37–54 g/kg D.M.) and a poor mineral nutrient composition.The increased use of vetch in the seed mixture had a buffering effect on dry-matter (D.M.) yield but this depended very much on crop N nutrition. For N-deficient conditions vetch inclusion increased the D.M. yield and had a strong positive effect on total forage crude protein (CP) and mineral composition. When crop N nutrition was good, very high D.M. yields (> 12 t D.M./ha) were possible using a high proportion of oats, with vetch making a reduced contribution to the yield and nutritive value of total forage.Seed rates suggested in the literature for Mediterranean conditions are adequate for low N inputs and low available soil N, but not for high D.M. yields which can only be obtained by using a higher proportion of oats and adequate N fertilizer.

scholarly journals Effectiveness of Sterile Insect Technique for Medfly (Ceratitis capitata, Wiedemann, 1824) Control in Citrus Orchards of Moulouya Perimeter North East of Morocco

2020 ◽  
Vol 4 (3) ◽  
pp. 405-421
Author(s):  
Jamal BEN YAZID ◽  
Z. CHAFIK ◽  
I. BIBI ◽  
E. KHARMACH
Keyword(s):  
Sterile Insect Technique ◽  
Ceratitis Capitata ◽  
Control Method ◽  
Male Population ◽  
Control Techniques ◽  
North East ◽  
North Eastern ◽  
Citrus Orchards ◽  
Eastern Morocco ◽  
Trap Catches

The Sterile Insect Technique (SIT) is an effective pest control method developed worldwide against many species of Fruit Flies. It involves the release of male insects sterilized, at pupae instar, by exposure to ionizing radiation.  The Area-wide control of medfly (Ceratitis capitata), with SIT based on sterile males release combined to other control techniques, was implemented since 2017 as a pilot area in Moulouya Perimeter in North-eastern Morocco. The main objective of this study is to evaluate the effectiveness of this tool in controlling Medfly and estimate sterile male population densities from data collected from trap catches after the release of a pre-determined number of sterile males in five Citrus orchards (0, 500, 1000 and 3000 sterile males per hectare) and the calculation of FTD (fly/trap/day) of sterile and wild males. The result showed that the percentage of recaptured males and FTD Sterile indices were related to release density by power function regression, while the sterile to wild ratio and release density were linear regression-adjusted. The finding confirmed the effectiveness of release in reducing the fly population in the TIS area by reducing the rate of citrus infestation in field and export shipments.  

Cryptodiaporthe populea. [Descriptions of Fungi and Bacteria].

1973 ◽  
Author(s):  
C. Booth
Keyword(s):  
Geographical Distribution ◽  
Western Europe ◽  
First Year ◽  
Severe Damage ◽  
North East ◽  
Conidial State ◽  
Wide Range ◽  
East Russia ◽  
Second Year ◽  
Old Trees

Abstract A description is provided for Cryptodiaporthe populea. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Poplar, willow. A wide range of poplar species are more or less susceptible, with members of the tacamahacca and algeros groups principally affected. Populus alba var. pyramidalis is very susceptible in Britain and P. alba and P. tremula are tolerant; complete resistance is unknown in the genus: The fungus has been recorded on cricket bat willow in Belgium. DISEASE: Dothichiza canker, Dorhichiza dieback, poplar canker. The conidial state is the form of this fungus most commonly found associated with the dieback or canker of poplar. The fungus is a wound parasite unable to invade sound bark tissues, although very small wounds, such as scars left by bud scales, may permit infection (38, 341). Infection usually occurs in the winter, when bark moisture and turgor are lowest (36, 673; 37, 684). First signs are a discoloration of the cortex under the bark, which develops to a sunken, dead patch of bark, often at the base of twigs or at the junction of first-year and second-year wood. The lesion may have an unpleasant odour and later develops black, globular, pycnidia on the surface. The lesion may heal over in a single season but it can spread to cause severe damage or death of the host. Injury is believed to be due to toxin formation as well as physical girdling by the canker (35, 797; 38, 103). The crowns of old trees or young plants in nurseries and plantations are mainly affected. The disease may be distinguished from that caused by Valsa sordida Nits. by its larger conidia and larger and less frequent stromata in infected tissues. GEOGRAPHICAL DISTRIBUTION: Europe (all western Europe excluding Portugal, Norway, Yugoslavia, Rumania, Bulgaria, Poland, Estonia, Ukraine and south-east Russia). Near East (Turkey, Cyprus). North America (east Canada, north-east USA). South America (Argentina) (CMI Map 344, ed. 2, 1968). TRANSMISSION: Mainly by airborne splash-dispersed conidia.

Phytoseiidae mites associated with native and cultivated solanaceous in Central-West Brazil

2021 ◽  
Author(s):  
Mércia Elias Duarte ◽  
Peterson Rodrigo Demite ◽  
Renata Santos De Mendonça ◽  
Miguel Michereff-filho ◽  
Maria Luiza Santa Cruz De Mesquita Alves ◽  
...  
Keyword(s):  
Biological Control ◽  
Morphological Traits ◽  
Common Species ◽  
Predatory Mites ◽  
Natural Environments ◽  
Phytoseiid Mites ◽  
Control Programs ◽  
Phytophagous Mites ◽  
Wild Host ◽  
The One

Predatory mites represent important biological control agents and those belonging to the Phytoseiidae family are the most promising for the control of phytophagous mites and small insects. The control of key pests of tomato and other solanaceous crops, highlighting phytophagous mites, has been a challenge and the biological control constitutes a promising strategy. Prospecting predatory mites in wild host plants, natural environments as well as in agroecosystems is relevant because these non-crop and crop areas can serve as reservoirs for promising species for biological control programs. This study aimed to know the Phytoseiidae fauna associated with wild and cultivated solanaceous plants in a poorly prospected area in Brazil, the Central-West Region. A detailed taxonomic identification of phytoseiid mites was conducted, and the most important morphological traits are presented for each species. In addition, associated phytophagous mites mainly belonging to the Tetranychidae, Tenuipalpidae and Eriophyoidea were identified. Surveys were carried out in 23 species of solanaceous collected in the Distrito Federal (12 areas) and Goiás State (1 area), from February 2017 to January 2018. Nineteen species of predators belonging to ten genera were recorded: Amblyseius (2 species), Euseius (3), Galendromus (1), Iphiseiodes (1), Neoseiulus (3), Paraphytoseius (1), Phytoseius (3), Proprioseiopsis (2), Typhlodromalus (2, one probably new to science) and Typhlodromips (1). Solanum lycocarpum was the solanaceous that harbored the highest richness (11 species), as well as the one with the highest abundance of phytoseiids (250 specimens). Typhlodromalus aripo was the most common species, being the most abundant (423 specimens; 32%) and registered on the largest number of hosts (14). Many of phytoseiid species found present morphological traits that facilitate their occurrence in leaves with trichomes, as in the case of tomato and other cultivated solanaceous. These traits and the association between predators and phytophagous mites may indicate that these species are promising for biological control programms. Thus, extensive studies to assess the efficiency of the identified predatory mites to control key solanaceous pests are required.

CRITERIA FOR SELECTING CHRYSOPA CARNEA BIOTYPES FOR BIOLOGICAL CONTROL: ADULT DIETARY REQUIREMENTS

1975 ◽  
Vol 107 (6) ◽  
pp. 589-595 ◽  
Author(s):  
Maurice J. Tauber ◽  
Catherine A. Tauber
Keyword(s):  
Biological Control ◽  
North America ◽  
West Coast ◽  
Biological Traits ◽  
The West ◽  
Control Programs ◽  
Preoviposition Period ◽  
Chrysopa Carnea ◽  
Control Adult ◽  
Agricultural Areas

AbstractBased on our studies with 10 geographic populations of Chrysopa carnea, we recommend that biological control programs involving this predator use "pure" carnea stock originating from eastern and midwestern North America. Of the two strains (races or biotypes) of C. carnea—carnea and mohave—carnea is the superior choice for biological control on commercial crops in both eastern and western North America because (1) its preoviposition period is approximately one-half as long as mohave’s, (2) unlike mohave adults, neither sex of the carnea strain requires prey for successful mating and initiating oviposition, (3) carnea’s oviposition can be enhanced in the field by applying currently available food sprays, and (4) carnea is efficient to mass-rear on a commercial basis.The “pure” mohave race is restricted to limited areas on the west coast. This race, which can enter a food-mediated summer diapause, is more suitable for biological control on the west coast in non-agricultural situations dominated by native vegetation, where prey occurrence is highly variable during summer.Most west coast populations in agricultural areas are composed of intermediates between the carnea and mohave races. F1 hybrids produced by crossing individuals from mohave, carnea, and intermediate populations, show predominantly carnea characteristics, and inheritance of the distinguishing biological traits appears to be controlled by polygenes.

scholarly journals RNAflow: An Effective and Simple RNA-Seq Differential Gene Expression Pipeline Using Nextflow

Genes ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1487
Author(s):  
Marie Lataretu ◽  
Martin Hölzer
Keyword(s):  
Gene Expression ◽  
Homo Sapiens ◽  
Standard Technique ◽  
Common Species ◽  
Rna Seq ◽  
Rna Molecules ◽  
Gene Filtering ◽  
Differential Gene ◽  
High Level ◽  
Very High

RNA-Seq enables the identification and quantification of RNA molecules, often with the aim of detecting differentially expressed genes (DEGs). Although RNA-Seq evolved into a standard technique, there is no universal gold standard for these data’s computational analysis. On top of that, previous studies proved the irreproducibility of RNA-Seq studies. Here, we present a portable, scalable, and parallelizable Nextflow RNA-Seq pipeline to detect DEGs, which assures a high level of reproducibility. The pipeline automatically takes care of common pitfalls, such as ribosomal RNA removal and low abundance gene filtering. Apart from various visualizations for the DEG results, we incorporated downstream pathway analysis for common species as Homo sapiens and Mus musculus. We evaluated the DEG detection functionality while using qRT-PCR data serving as a reference and observed a very high correlation of the logarithmized gene expression fold changes.

Extremely high diversity of euglenophytes in a small pond in eastern Poland

2018 ◽  
Vol 151 (1) ◽  
pp. 18-34 ◽  
Author(s):  
Małgorzata Poniewozik ◽  
Josef Juráň
Keyword(s):  
Chemical Properties ◽  
Diversity Indices ◽  
Common Species ◽  
Temperature Conductivity ◽  
Upgma Cluster Analysis ◽  
Water Ph ◽  
Special Concern ◽  
Physical And Chemical ◽  
Very High ◽  
And Chemical Properties

Background and aims – Phytoplankton samples were taken from a periodic, small and very shallow former clay-pit pond in eastern Poland near Lublin city. Diversity of the euglenophyte community was assessed during the period 2002–2004 and in 2014. Methods – Water samples were collected with a 20 µm plankton net and with a slime aspirator (20 ml capacity) from the surface of the bottom. One aliquot of each sample was fixed for SEM observation; the fresh part of the sample was analysed using light microscope. Physical and chemical properties of the water (pH, temperature, conductivity, phosphates and ammonium salt contents) were measured. Diversity indices were calculated (Shannon-Wiener, evenness, Margalef and Simpson) and UPGMA cluster analysis was applied to discern differences among euglenoid assemblages.Key results – In total, 63 euglenophyte taxa were found. The euglenophyte community was dominated by species belonging to the Trachelomonas genus (29 taxa). The most abundant and constant component were widespread and common species such as T. caudata, T. hispida, T. intermedia, T. volvocina and T. volvocinopsis. They usually occurred in very high densities. We also found some rarely reported euglenophytes including Euglena granulata, Trachelomonas lemmermannii, and T. sydneyensis. Conclusions – Euglenophytes were, with a few exceptions, the only group inhabiting the pond. Representatives of other groups such as diatoms or Scenedesmus species were recorded only occasionally. Nearly half of the taxa that were recorded in the first period (2002–2004) were found again after ten years. Of special concern was taxa belonging to the genus Trachelomonas. Trachelomonads, although known to represent taxa preferring waters moderately rich in nutrients, were very numerous in the investigated pond, which was enriched in phosphorus and nitrogen compounds.

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