METARHIZIUM FLAVOVIRIDE (FI985) AS A PROMISING MYCOINSECTICIDE FOR AUSTRALIAN ACRIDIDS

AbstractOnly one isolate of Metarhizium flavoviride Gams and Roszypal group 3 has been isolated from a field-infected acridid in Australia. This is isolate FI985 (ARSEF 324) obtained from a spur-throated locust, Austracris guttulosa (Walker), near Rockhampton, Queensland, in 1979. In terms of conidial size and shape as well as phialide morphology, FI985 is intermediate between Metarhizium anisopliae (Metschnikoff) Sorokin and M. flavoviride. It has been compared with other group 3 isolates using RAPDs and sequence analysis of the ITS region and found to be very similar. However the analysis shows that these group 3 isolates are genetically closer to M. anisopliae than to M. flavoviride sensu stricto. Laboratory bioassays have shown that FI985 is virulent for five species of acridid pests in Australia. Comparative bioassays with other isolates of Metarhizium, including other group 3 isolates from Africa and Asia, have not yet revealed any isolate more virulent than FI985. This isolate is amenable to mass-production on rice and has been formulated in oil as a mycoinsecticide. The results from six field tests, mostly against wingless grasshopper, Phaulacridium vittatum (SjÖstedt), using doses of 2–7 × 1012 conidia per hectare and plot sizes up to 50 ha are summarized. These trials (with the exception of the first against the Australian plague locust) have given high levels of disease-related mortality in caged samples of the target collected within 3 days of spraying. In the four trials with wingless grasshopper, population reductions were detected 10–30 days after application; however these reductions were much less than suggested by cage samples as a result of movement of the target acridids. In contrast, positive control plots sprayed with fenitrothion gave a very high initial kill (>90% in 1 day) but were then more rapidly reinvaded. Consequently, 3–4 weeks after spraying the density in the plots treated with chemical insecticide and those treated with mycoinsecticide were similar. Further field trials are needed especially against the Australian plague locust and evaluating lower doses. The results obtained to date show that a mycoinsecticide based on FI985 is likely to be effective over a wide range of target acridids and weather conditions.

Download Full-text

Managing Bees for Delivering Biological Control Agents and Improved Pollination in Berry and Fruit Cultivation

Sustainable Agriculture Research ◽

10.5539/sar.v4n3p89 ◽

2015 ◽

Vol 4 (3) ◽

pp. 89 ◽

Cited By ~ 8

Author(s):

Heikki M. T. Hokkanen ◽

Ingeborg Menzler-Hokkanen ◽

Marja-Leena Lahdenpera

Keyword(s):

Crop Protection ◽

Field Tests ◽

Weather Conditions ◽

Field Studies ◽

Field Trials ◽

Marketable Yield ◽

Dissemination Activity ◽

Grey Mold ◽

Commercial Farms ◽

Disease Pressure

Targeted precision biocontrol and improved pollination were studied Europe-wide in the EU ERA-NET CORE ORGANIC 2 project BICOPOLL (Biocontrol and Pollination). A case study was conducted on the management of strawberry grey mold Botrytis cinerea, with the biocontrol fungus, Gliocladium catenulatum, vectored by honey bees or bumble bees. A joint field trial carried out in five countries targeted strawberry cultivations in open field, and included four treatments: untreated control, chemical fungicide, entomovectored biocontrol, and chemical and biocontrol combined. In organic fields, no pesticide treatments were included. The proportion of moldy berries, and/or the marketable yield of healthy berries were recorded from each treatment, along with other parameters of local interest. A pilot study was started in Finland in 2006, and, by 2012, large commercial farms were using entomovectoring. In 2012, field trials were started in Estonia and in Italy, and in 2013-14, these experiments were expanded to Slovenia and Turkey. In total, 26 field tests were conducted using entomovectoring and Gliocladium catenulatum (Prestop® Mix) on strawberry, with five additional trials on raspberry. Efficacy results have been excellent throughout the field studies. The results show crop protection equalling or exceeding that provided by a full chemical fungicide program, under all weather conditions, and over a wide geographical range (from Finland to Turkey). Under heavy disease pressure, entomovectoring provided on average a 47% disease reduction, which was the same as multiple fungicide sprays. Under light disease pressure, biocontrol decreased grey mold by an average of 66%, which was greater than fungicide sprays. The concept has proven to be effective on strawberries, raspberries, pears, apples, blueberries, cherries, and grapes. A conservative estimate for Finland is that over 500 ha of strawberry cultivation currently use the technique (≈15% of the strawberry growing area). To make full use of the entomovectoring technique, organic berry and fruit growers are encouraged to (i) keep bees, or to hire the service from local beekeepers for entomovectoring; and (ii) manage vegetation within and around the target crop to support the activity of bees and other pollinators, which can help to disseminate the beneficial microbial populations within the crop. Beekeepers are encouraged to (i) market pollination and biocontrol services to fruit and berry growers, and (ii) ensure that all operations are effective in mananging bees and their microbe dissemination activity. Biocontrol product manufacturers are encouraged to further develop products and their formulations specifically for entomovectoring, because current formulations are suboptimal as they are initially optimized for other uses (e.g., mixing into the soil).

Download Full-text

Vulnerability of sweet cherry cultivars to continuous periods of spring frosts in Plovdiv, Bulgaria

Agricultural Science and Technology ◽

10.15547/ast.2020.04.055 ◽

2020 ◽

Vol 12 (4) ◽

pp. 348-352

Author(s):

S. Malchev ◽

S. Savchovska

Keyword(s):

Sweet Cherry ◽

Weather Conditions ◽

Frost Damage ◽

Cold Weather ◽

Bud Burst ◽

Intermediate Group ◽

Air Temperatures ◽

Wide Range ◽

Group Form ◽

Sweet Cherry Cultivars

Abstract. The periods with continuous freezing air temperatures reported during the spring of 2020 (13 incidents) affected a wide range of local and introduced sweet cherry cultivars in the region of Plovdiv. They vary from -0.6°C on March 02 to -4.9°C on March 16-17. The duration of influence of the lowest temperatures is 6 and 12 hours between March 16 and 17. The inspection of fruit buds and flowers was conducted twice (on March 26 and April 08) at different phenological stages after continuous waves of cold weather conditions alternated with high temperatures. During the phenological phase ‘bud burst’ (tight cluster or BBCH 55) some of the flowers in the buds did not develop further making the damage hardly detectable. The most damaged are hybrid El.28-21 (95.00%), ‘Van’ (91.89%) and ‘Bing’ (89.41%) and from the next group ‘Lapins’ (85.98%) and ‘Rosita’ (83.33%). A larger intermediate group form ‘Kossara’ (81.67%), ‘Rozalina’ (76.00%), ‘Sunburst’ (75.00%), ‘Bigarreau Burlat’ (69.11%) and ‘Kuklenska belitza’ (66.67%). Candidate-cultivar El.17-90 ‘Asparuh’ has the lowest frost damage values of 55.00% and El.17-37 ‘Tzvetina’ with damage of 50.60%.

Download Full-text

Control of Winged Waterprimrose (Jussiaea decurrens) and Northern Jointvetch (Aeschynomene virginica) with Fungal Pathogens

Weed Science ◽

10.1017/s0043174500044477 ◽

1979 ◽

Vol 27 (5) ◽

pp. 497-501 ◽

Cited By ~ 46

Author(s):

C. D. Boyette ◽

G. E. Templeton ◽

R. J. Smith

Keyword(s):

Oryza Sativa ◽

Glycine Max ◽

Fungal Pathogens ◽

Liquid Culture ◽

Field Experiments ◽

Colletotrichum Gloeosporioides ◽

Pathogenic Fungus ◽

Field Tests ◽

Wide Range ◽

Growing Region

An indigenous, host-specific, pathogenic fungus that parasitizes winged waterprimrose [Jussiaea decurrens(Walt.) DC.] is endemic in the rice growing region of Arkansas. The fungus was isolated and identified asColletotrichum gloeosporioides(Penz.) Sacc. f.sp. jussiaeae(CGJ). It is highly specific for parasitism of winged waterprimrose and not parasitic on creeping waterprimrose (J. repensL. var.glabrescensKtze.), rice (Oryza sativaL.), soybeans [Glycine max(L.) Merr.], cotton (Gossypium hirsutumL.), or 4 other crops and 13 other weeds. The fungus was physiologically distinct from C.gloeosporioides(Penz.) Sacc. f. sp.aeschynomene(CGA), an endemic anthracnose pathogen of northern jointvetch[Aeschynomene virginica(L.) B.S.P.], as indicated by cross inoculations of both weeds. Culture in the laboratory and inoculation of winged waterprimrose in greenhouse, growth chamber and field experiments indicated that the pathogen was stable, specific, and virulent in a wide range of environments. The pathogen yielded large quantities of spores in liquid culture. It is suitable for control of winged waterprimrose. Winged waterprimrose and northern jointvetch were controlled in greenhouse and field tests by application of spore mixtures of CGJ and CGA at concentrations of 1 to 2 million spores/ml of each fungus in 94 L/ha of water; the fungi did not damage rice or nontarget crops.

Download Full-text

Conventional and Conservation Seedbed Preparation Systems for Wheat Planting in Silty-Clay Soil

Sustainability ◽

10.3390/su13116506 ◽

2021 ◽

Vol 13 (11) ◽

pp. 6506

Author(s):

Roberto Fanigliulo ◽

Daniele Pochi ◽

Pieranna Servadio

Keyword(s):

Clay Soil ◽

Conservation Tillage ◽

Field Tests ◽

Superficial Layer ◽

Soil Tillage ◽

Energy Requirements ◽

Silty Clay ◽

Wide Range ◽

Seedbed Preparation ◽

Silty Clay Soil

Conventional seedbed preparation is based on deep ploughing followed by lighter and finer secondary tillage of the superficial layer, normally performed by machines powered by the tractor’s Power Take-Off (PTO), which prepares the seedbed in a single pass. Conservation methods are based on a wide range of interventions, such as minimum or no-tillage, by means of machines with passive action working tools which require two or more passes The aim of this study was to assess both the power-energy requirements of conventional (power harrows and rotary tillers with different working width) and conservation implements (disks harrow and combined cultivator) and the soil tillage quality parameters, with reference to the capability of preparing an optimal seedbed for wheat planting. Field tests were carried out on flat, silty-clay soil, using instrumented tractors. The test results showed significant differences among the operative performances of the two typologies of machines powered by the tractor’s PTO: the fuel consumption, the power and the energy requirements of the rotary tillers are strongly higher than power harrows. However, the results also showed a decrease of these parameters proceeding from conventional to more conservation tillage implements. The better quality of seedbed was provided by the rotary tillers.

Download Full-text

Modified Humic Substances as Soil Conditioners: Laboratory and Field Trials

Agronomy ◽

10.3390/agronomy11010150 ◽

2021 ◽

Vol 11 (1) ◽

pp. 150

Author(s):

Natalia A. Kulikova ◽

Alexander B. Volikov ◽

Olga I. Filippova ◽

Vladimir A. Kholodov ◽

Nadezhda V. Yaroslavtseva ◽

...

Keyword(s):

Humic Substances ◽

Soil Aggregates ◽

Field Tests ◽

Performance Testing ◽

Field Trials ◽

Soil Conditioner ◽

Model Soil ◽

Substrate Induced Respiration ◽

And Performance ◽

Survival Of Seedlings

The paper is devoted to the development and performance testing of a soil conditioner based on leonardite humic substances (LHS) modified with 3-aminopropyltriethoxysilane (APTES). The modified HS were obtained by adding APTES to LHS solution at different mass ratios of LHS and APTES, followed by the investigation of siloxane structures using 31Si NMR spectroscopy. The Urbic Technosol was used as a model soil. The size and amount of water-stable soil aggregates were estimated using wet sieving and laser diffraction, respectively. Toxicity was evaluated by monitoring microbial substrate-induced respiration (SIR) and seedling bioassay. Laboratory column experiments demonstrated an increase in water-stability of the 3–5 mm soil aggregates after LHS-APTES application. Field tests showed an increase in the average weighted diameter of micro aggregates (from 59 to 73 μm) and water-stable macroaggregates (from 1.6 to 2.9 mm) due to the LHS-APTES amendment. A substantial increase in SIR from 5 to 9 mg CO2 (kg h)−1 was detected. Better survival of seedlings was observed. The obtained beneficial results indicate that APTES-modified HS can be successfully used as a soil conditioner. The formation of extended siloxane networks was suggested as the main mechanism of the observed improvement in the structure of the amended soils.

Download Full-text

Grain mineral density of bread and durum wheat landraces from geochemically diverse native soils

Crop and Pasture Science ◽

10.1071/cp17306 ◽

2018 ◽

Vol 69 (4) ◽

pp. 335 ◽

Cited By ~ 4

Author(s):

José Francisco Vázquez ◽

Efraín Antonio Chacón ◽

José María Carrillo ◽

Elena Benavente

Keyword(s):

Durum Wheat ◽

Triticum Aestivum L ◽

Field Trials ◽

Mineral Elements ◽

Small Scale ◽

Mineral Density ◽

Native Soil ◽

Wide Range ◽

Grain Zinc ◽

Wheat Landraces

Future progress on the creation of wheat cultivars with high grain zinc (Zn) and iron (Fe) mineral density will depend on both the availability of suitable donor germplasm and the identification of genes or quantitative trait loci contributing to increase the accumulation of mineral elements in the wheat kernels. Multi-environment field trials were conducted to evaluate the grain Zn, Fe and protein concentration of 32 bread wheat (Triticum aestivum L.) and 20 durum wheat (T. turgidum L. var. durum) landraces locally adapted to soils covering a wide range of pH values and mineral composition. These landraces were selected after a preliminary, small-scale field trial that had analysed 425 Spanish local varieties. Analyses of variance demonstrated a significant effect of genotype on grain composition, and 16 wheat landraces with elevated grain Zn and/or Fe density across the environments were identified. These landraces rich in grain minerals represent valuable primary gene-pool parents for wheat biofortification. No pattern of native soil geochemical characteristics that could help to predict the success in collecting mineral-dense genotypes in a given area was found. Mapping populations derived from some pairs of grain-mineral-rich and -poor genotypes characterised in the study may facilitate the development of molecular markers to assist the selection of superior wheat genotypes.

Download Full-text

Modeling of Yield Losses Caused by Potato Late Blight on Eight Cultivars with Different Levels of Resistance to Phytophthora infestans

Plant Disease ◽

10.1094/pdis-09-11-0752 ◽

2012 ◽

Vol 96 (7) ◽

pp. 935-942 ◽

Cited By ~ 10

Author(s):

Toky Rakotonindraina ◽

Jean-Éric Chauvin ◽

Roland Pellé ◽

Robert Faivre ◽

Catherine Chatot ◽

...

Keyword(s):

Late Blight ◽

Phytophthora Infestans ◽

Relative Yield ◽

Weather Conditions ◽

Potato Late Blight ◽

Yield Losses ◽

Predictive Quality ◽

Wide Range ◽

Cultivar Susceptibility

The Shtienberg model for predicting yield loss caused by Phytophthora infestans in potato was developed and parameterized in the 1990s in North America. The predictive quality of this model was evaluated in France for a wide range of epidemics under different soil and weather conditions and on cultivars different than those used to estimate its parameters. A field experiment was carried out in 2006, 2007, 2008, and 2009 in Brittany, western France to assess late blight severity and yield losses. The dynamics of late blight were monitored on eight cultivars with varying types and levels of resistance. The model correctly predicted relative yield losses (efficiency = 0.80, root mean square error of prediction = 13.25%, and bias = –0.36%) as a function of weather and the observed disease dynamics for a wide range of late blight epidemics. In addition to the evaluation of the predictive quality of the model, this article provides a dataset that describes the development of various late blight epidemics on potato as a function of weather conditions, fungicide regimes, and cultivar susceptibility. Following this evaluation, the Shtienberg model can be used with confidence in research and development programs to better manage potato late blight in France.

Download Full-text

A Review of Detection and Removal of Raindrops in Automotive Vision Systems

Journal of Imaging ◽

10.3390/jimaging7030052 ◽

2021 ◽

Vol 7 (3) ◽

pp. 52

Author(s):

Yazan Hamzeh ◽

Samir A. Rawashdeh

Keyword(s):

Detrimental Effect ◽

Weather Conditions ◽

Traffic Sign ◽

Survey Paper ◽

Sign Recognition ◽

Adverse Weather Conditions ◽

Wide Range ◽

Adverse Weather ◽

Protective Cover

Research on the effect of adverse weather conditions on the performance of vision-based algorithms for automotive tasks has had significant interest. It is generally accepted that adverse weather conditions reduce the quality of captured images and have a detrimental effect on the performance of algorithms that rely on these images. Rain is a common and significant source of image quality degradation. Adherent rain on a vehicle’s windshield in the camera’s field of view causes distortion that affects a wide range of essential automotive perception tasks, such as object recognition, traffic sign recognition, localization, mapping, and other advanced driver assist systems (ADAS) and self-driving features. As rain is a common occurrence and as these systems are safety-critical, algorithm reliability in the presence of rain and potential countermeasures must be well understood. This survey paper describes the main techniques for detecting and removing adherent raindrops from images that accumulate on the protective cover of cameras.

Download Full-text

In-field screening for host plant resistance to Delia radicum and Brevicoryne brassicae within selected rapeseed cultivars and new interspecific hybrids

Open Life Sciences ◽

10.1515/biol-2020-0074 ◽

2020 ◽

Vol 15 (1) ◽

pp. 711-720

Author(s):

Janetta Niemann ◽

Justyna Szwarc ◽

Jan Bocianowski ◽

Dorota Weigt ◽

Marek Mrówczyński

Keyword(s):

Life Sciences ◽

Field Trials ◽

Brevicoryne Brassicae ◽

Delia Radicum ◽

Sources Of Resistance ◽

Cabbage Aphid ◽

Hybrid Combination ◽

Resistance To Insects ◽

Wide Range ◽

High Level

AbstractRapeseed (Brassica napus) can be attacked by a wide range of pests, for example, cabbage root fly (Delia radicum) and cabbage aphid (Brevicoryne brassicae). One of the best methods of pest management is breeding for insect resistance in rapeseed. Wild genotypes of Brassicaceae and rapeseed cultivars can be used as a source of resistance. In 2017, 2018, and 2019, field trials were performed to assess the level of resistance to D. radicum and B. brassicae within 53 registered rapeseed cultivars and 31 interspecific hybrid combinations originating from the resources of the Department of Genetics and Plant Breeding of Poznań University of Life Sciences (PULS). The level of resistance varied among genotypes and years. Only one hybrid combination and two B. napus cultivars maintained high level of resistance in all tested years, i.e., B. napus cv. Jet Neuf × B. carinata – PI 649096, Galileus, and Markolo. The results of this research indicate that resistance to insects is present in Brassicaceae family and can be transferred to rapeseed cultivars. The importance of continuous improvement of rapeseed pest resistance and the search for new sources of resistance is discussed; furthermore, plans for future investigations are presented.

Download Full-text

Comparison of Water and Gas Tracers Field Breakthrough

10.2118/205863-ms ◽

2021 ◽

Author(s):

Hsieh Chen ◽

Sehoon Chang ◽

Gawain Thomas ◽

Wei Wang ◽

Afnan Mashat ◽

...

Keyword(s):

Mass Spectrometry ◽

Gas Phase ◽

Detection Method ◽

Tracer Tests ◽

Field Tests ◽

Field Trials ◽

Breakthrough Curves ◽

Detection Methods ◽

Reservoir Conditions ◽

Gas Tracer

Abstract We are developing new classes of barcoded advanced tracers, which, compared to present commercial offerings, can be optically detected in an automated fashion. The eventual goal for the advanced tracers is to deploy cost-effective, ubiquitous, long-term, and full-field tracer tests in supporting large-scale waterflooding optimization for improved oil recovery. In this paper, we compare model predictions to breakthrough data from two field tests of advanced tracers in a pilot during water alternating gas (WAG) cycles, where gas tracer tests have recently been performed as well. Two advanced tracer injections were performed at the test site. For the first injection, only a dipicolinic acid based advanced tracer (DPA) was injected. For the second injection, DPA and a phenanthroline- based advanced tracer, 4,7-bis(sulfonatophenyl)-1,10-phenanthroline-2,9-dicarboxylic acid (BSPPDA), was injected in conjunction with a commercially available fluorobenzoic acid-based tracer (FBA) to benchmark their performance. Produced water samples were collected weekly for tracer analysis. Both newly developed 2D-high performance liquid chromatography/time-resolved fluorescence optical detection method (2D-HPLC/TRF) and liquid chromatography-mass spectrometry (LC-MS) were used to construct the breakthrough curves for the advanced tracers. In parallel, gas chromatography-mass spectrometry (GC-MS) was used to detect FBA tracer. Gas tracer tests have been performed on the same field. Since DPA, BSPPDA and FBA tracers were water tracers as designed, they were expected to appear in between gas tracer breakthroughs, and we observed exactly that for BSPPDA and FBA. Unexpectedly, the DPA predominantly appeared along with gas tracer breakthroughs, suggesting its favorable compatibility with the gas phase. We suspect the presence of some gas components rendered the medium more acidic, which likely protonates DPA molecules, thereby alters its hydrophilicity. A wealth of information could be gathered from the field tests. First, all tracers survived not only the harsh reservoir conditions but also the irregular WAG injections. Their successful detection from the producers suggested robustness of these materials for reservoir applications. Second, the breakthrough curves of the BSPPDA tracers using optical detection method were very similar to those of FBA tracers detected by GC-MS, substantiating the competency of our in-house materials and detection methods to the present commercial offerings. Finally, even though DPA has passed prior lab tests as a good water tracer, its high solubility to gas phase warrants further investigation. This paper summarizes key results from two field trials of the novel barcoded advanced tracers, of which both the tracer materials and detection methods are new to the industry. Importantly, the two co- injected advanced tracers showed opposite correlations to the gas tracers, highlighting the complex physicochemical interactions in reservoir conditions. Nevertheless, the information collected from the field trials is invaluable in enabling further design and utilization of the advanced tracers in fulfilling their wonderful promises.

Download Full-text