The soil habitat | ScienceGate

Entomopathogenic fungi (EPF) are the natural enemies of insect-pests. However, EPF recoveries can be influenced by the soil habitat-type(s) incorporated and/or the bait-insect(s) used. Galleriamellonella (GM) as bait-insect, i.e. ‘Galleria-bait’, is arguably the most common methodology, which is sometimes used solely, to isolate EPF from soils. Insect baiting using Tenebriomolitor (TM) has also been employed occasionally. Here 183 soils were used to estimate the functional diversity of EPF in Portuguese Douro vineyards (cultivated habitat) and adjacent hedgerows (semi-natural habitat), using the TM bait method. Moreover, to study the effect of insect baiting on EPF recovery, 81 of these 183 soil samples were also tested for EPF occurrences using the GM bait method. Twelve species were found in 44.26% ± 3.67% of the total of 183 soils. Clonostachysroseaf.rosea was found in maximum soils (30.05% ± 3.38%), followed by Beauveriabassiana (12.57% ± 2.37%), Purpureocilliumlilacinum (9.29% ± 2.14%) and Metarhiziumrobertsii (6.01% ± 1.75%). Beauveriapseudobassiana (P < 0.001), C.roseaf.rosea (P = 0.006) and Cordycepscicadae (P=0.023) were isolated significantly more from hedgerows, highlighting their sensitivities towards agricultural disturbances. Beauveriabassiana (P = 0.038) and M.robertsii (P = 0.003) were isolated significantly more using GM and TM, respectively. Principal component analysis revealed that M.robertsii was associated both with TM baiting and cultivated habitats, however, B.bassiana was slightly linked with GM baiting only. Ecological profiles of B.bassiana and P.lilacinum were quite similar while M.robertsii and C.roseaf.rosea were relatively distant and distinct. To us, this is the first report on (a) C.cicadae isolation from Mediterranean soils, (b) Purpureocilliumlavendulum as an EPF worldwide; and (c) significant recoveries of M.robertsii using TM over GM. Overall, a ‘Galleria-Tenebrio-bait method’ is advocated to study the functional diversity of EPF in agroecosystems.

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Corrigendum - Frequency of annual species of Medicago on the major soil groups of the Mcquarie region of New South Wales

Australian Journal of Agricultural Research ◽

10.1071/ar9600705c ◽

1960 ◽

Vol 11 (5) ◽

pp. 705

Author(s):

WD Andrew ◽

FW Hely

Keyword(s):

New South ◽

New South Wales ◽

Salt Content ◽

Acid Group ◽

Soluble Salt ◽

Annual Species ◽

South Wales ◽

Soil Groups ◽

Soil Habitat ◽

Poor Drainage

The frequency of eight annual species of Medicago was determined on 10 soil groups in a region climatically favourable for medics. They occurred on nine of these, the overall frequency being in the order M. minima (L.) Bart. > M. denticulata Willd. > M. laciniata (L.) Mill., M. praecox DC., M. tribuloides Desr., and M. orbicularis (L.) Bart. > M. arabica (L.) Huds. and M. confinis Koch. M. minima was more tolerant of variation of soil habitat than any other medic in the region. M. denticulata was most commonly found on the soils of high soluble salt content and showed the greatest tolerance of poor drainage conditions. M. laciniata occurred in greatest abundance on soils of the well-drained brown acid group. M. praecox was most commonly found on soils with a compact gravelly surface. M. tribuloides was recorded on five soil groups but was common only on the black earths. M. orbicularis was confined to the black earth and red loam soils. M. arabica was rarely found, being restricted to lower, fertile, well-drained parts of the landscape, and M. confinis occurred only occasionally and then in association with M. denticulata.

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The multi-layered protective cuticle of Collembola: a chemical analysis

Journal of The Royal Society Interface ◽

10.1098/rsif.2014.0619 ◽

2014 ◽

Vol 11 (99) ◽

pp. 20140619 ◽

Cited By ~ 42

Author(s):

Julia Nickerl ◽

Mikhail Tsurkan ◽

René Hensel ◽

Christoph Neinhuis ◽

Carsten Werner

Keyword(s):

Electron Microscopy ◽

Chemical Composition ◽

Chemical Analysis ◽

Decisive Role ◽

Arthropod Cuticle ◽

Characteristic Layers ◽

Protein Rich ◽

Base Structure ◽

Soil Habitat

Collembola, also known as springtails, are soil-dwelling arthropods that typically respire through the cuticle. To avoid suffocating in wet conditions, Collembola have evolved a complex, hierarchically nanostructured, cuticle surface that repels water with remarkable efficiency. In order to gain a more profound understanding of the cuticle characteristics, the chemical composition and architecture of the cuticle of Tetrodontophora bielanensis was studied. A stepwise removal of the different cuticle layers enabled controlled access to each layer that could be analysed separately by chemical spectrometry methods and electron microscopy. We found a cuticle composition that consisted of three characteristic layers, namely, a chitin-rich lamellar base structure overlaid by protein-rich nanostructures, and a lipid-rich envelope. The specific functions, composition and biological characteristics of each cuticle layer are discussed with respect to adaptations of Collembola to their soil habitat. It was found that the non-wetting characteristics base on a rather typical arthropod cuticle surface chemistry which confirms the decisive role of the cuticle topography.

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Characterization of Arthrobacter strains isolated from the pine environment that inhibit Fusarium moniliforme var. subglutinans, the causal agent of pine pitch canker

Canadian Journal of Microbiology ◽

10.1139/m83-213 ◽

1983 ◽

Vol 29 (10) ◽

pp. 1382-1389 ◽

Cited By ~ 3

Author(s):

Jane Barrows-Broaddus ◽

Shari D. Teeslink ◽

Thomas J. Kerr

Keyword(s):

Fusarium Moniliforme ◽

Causal Agent ◽

Pine Bark ◽

Dual Culture ◽

Pitch Canker ◽

Overlapping Clusters ◽

Taxonomic Analysis ◽

Inhibition Zones ◽

Soil Habitat

Forty-three Arthrobacter strains isolated from the canopy and soil in stands of southern pines were characterized and compared with seven named strains of Arthrobacter using numerical taxonomic analysis. The analysis placed 24 of the pine isolates into four overlapping clusters, leaving 8 that matched with 1 to several isolates and 18 that matched with none. All isolates within clusters inhibited fusaria in dual culture, but the nonclustered pine strains varied in their ability to produce inhibition zones against Fusarium moniliforme var. subglutinans, the causal agent of pine pitch canker. The seven named Arthrobacter strains did not cluster with any of the pine isolates nor did they inhibit F. moniliforme var. subglutinans in dual culture. Isolates tested from each cluster did not produce bacteriocinlike compounds against isolates within a cluster nor did they produce bacteriocinlike compounds against isolates that matched in other clusters. Nonmatching isolates, whether from different clusters, strains, or species, frequently produced bacteriocinlike compounds against each other. Membership in a cluster was not correlated with the source of isolation. Many of the isolates from pine bark and needles matched those from the soil. All of the nonclustered pine strains, however, came from the pine canopy, indicating a possible divergence of these isolates from those in the soil habitat.

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Entomopathogenic fungi in Portuguese vineyards soils: suggesting a ‘Galleria-Tenebrio-bait method’ as bait-insects Galleria and Tenebrio significantly underestimate the respective recoveries of Metarhizium (robertsii) and Beauveria (bassiana)

MycoKeys ◽

10.3897/mycokeys.38.26970 ◽

2018 ◽

Vol 38 ◽

pp. 1-23 ◽

Cited By ~ 2

Author(s):

Lav Sharma ◽

Irene Oliveira ◽

Laura Torres ◽

Guilhermina Marques

Keyword(s):

Functional Diversity ◽

Entomopathogenic Fungi ◽

Insect Pests ◽

Natural Habitat ◽

Habitat Type ◽

Principal Component ◽

Metarhizium Robertsii ◽

Bait Method ◽

Ecological Profiles ◽

Soil Habitat

Entomopathogenic fungi (EPF) are the natural enemies of insect-pests. However, EPF recoveries can be influenced by the soil habitat-type(s) incorporated and/or the bait-insect(s) used. Galleriamellonella (GM) as bait-insect, i.e. ‘Galleria-bait’, is arguably the most common methodology, which is sometimes used solely, to isolate EPF from soils. Insect baiting using Tenebriomolitor (TM) has also been employed occasionally. Here 183 soils were used to estimate the functional diversity of EPF in Portuguese Douro vineyards (cultivated habitat) and adjacent hedgerows (semi-natural habitat), using the TM bait method. Moreover, to study the effect of insect baiting on EPF recovery, 81 of these 183 soil samples were also tested for EPF occurrences using the GM bait method. Twelve species were found in 44.26% ± 3.67% of the total of 183 soils. Clonostachysroseaf.rosea was found in maximum soils (30.05% ± 3.38%), followed by Beauveriabassiana (12.57% ± 2.37%), Purpureocilliumlilacinum (9.29% ± 2.14%) and Metarhiziumrobertsii (6.01% ± 1.75%). Beauveriapseudobassiana (P < 0.001), C.roseaf.rosea (P = 0.006) and Cordycepscicadae (P=0.023) were isolated significantly more from hedgerows, highlighting their sensitivities towards agricultural disturbances. Beauveriabassiana (P = 0.038) and M.robertsii (P = 0.003) were isolated significantly more using GM and TM, respectively. Principal component analysis revealed that M.robertsii was associated both with TM baiting and cultivated habitats, however, B.bassiana was slightly linked with GM baiting only. Ecological profiles of B.bassiana and P.lilacinum were quite similar while M.robertsii and C.roseaf.rosea were relatively distant and distinct. To us, this is the first report on (a) C.cicadae isolation from Mediterranean soils, (b) Purpureocilliumlavendulum as an EPF worldwide; and (c) significant recoveries of M.robertsii using TM over GM. Overall, a ‘Galleria-Tenebrio-bait method’ is advocated to study the functional diversity of EPF in agroecosystems.

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