scholarly journals Gypsy Moth Management with LdMNPV Baculovirus in Cork Oak Forest

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 495
Author(s):  
Luca Ruiu ◽  
Roberto Mannu ◽  
Maurizio Olivieri ◽  
Andrea Lentini
Keyword(s):  
Population Dynamics ◽  
Gypsy Moth ◽  
Block Design ◽  
Larval Mortality ◽  
Larval Density ◽  
Management Program ◽  
Cork Oak ◽  
Forest Protection ◽  
Randomized Block Design ◽  
Species Specific

(1) Research Highlights: Applications of a species-specific baculovirus is a promising method to control the gypsy moth and regulate its population dynamics in forest ecosystems. (2) Background and Objectives: Cork oak protection against the Lepidopteran defoliator Lymantria dispar requires an appropriate forest ecosystem management program, involving the application of eco-sustainable microbial products during population outbreaks. The species-specific multicapsid nucleopolyhedrovirus (LdMNPV), agent of natural epizootics in gypsy moth populations, represents an option that was investigated in a multi-year field study, involving viral applications either from the ground or by aerial treatment. (3) Materials and Methods: Efficacy trials against L. dispar populations were conducted in 2018 and 2019 in Sardinia, according to a randomized block design. Each year, two trials were conducted, applying a baculovirus commercial formulation with an atomizer from the ground and assessing the effects of different doses and application timing, respectively. An aerial application trial distributing LdMNPV at ultra-low volumes (2 L/ha) was also conducted in 2019 to assess the virus efficacy at a larger field scale. (4) Results: In both years, a significant increase in larval mortality was detected in plots treated with higher viral occlusion body (OB) doses and with an earlier application targeting younger larvae, in comparison with untreated controls. Due to an observed retrogradation phase of the target pest in 2019, no significant differences in larval density between areas treated from a helicopter and control were detected, but in the few weeks following application, a meaningful vitality decrease in larval samples from treated plots was observed. (5) Conclusions: Based on the results of this study, the use of LdMNPV in forest protection programs against gypsy moth can be worth consideration in multi-year integrated program strategies to modulate population dynamics.

scholarly journals Peanut Productivity Under The Albizia Stand With Agroforestry System In Community Forest, Magetan East Java Indonesia

2021 ◽  
Vol 2 (1) ◽  
pp. 30-35
Author(s):  
Anang Susanto ◽  
M Winarni ◽  
Parwi
Keyword(s):  
Local Community ◽  
Block Design ◽  
Forest Degradation ◽  
Agroforestry System ◽  
Plant Spacing ◽  
Forest Protection ◽  
Opinion Change ◽  
Randomized Block Design ◽  
Initial Release ◽  
Forest Fire Prevention

An effort to meet the national food need is by utilizing productive forest areas under albizia stands. Food stuff such as peanuts can grow under albizia forest stands. The purpose of this research was to know success of agroforestry system implemented to tree after initial release of contract. This study was conducted under albizia stand of state forest Magetan in East Java. Research design was used in this study was randomized block design. 5- year- old albizia stages with 0%, 25%, 50 % trimming intensity with plant spacing of   3 m x 4 m, Albizia trees that used for this comparison as many as 90 albizia trees. Results showed that soil lies under 5-year-old albizia trees still produced peanut with highest weights 129 g/m and lowest weight 117 g/m2 while highest biomass about 115.10 g and lowest biomass about 98.23 g. Application of agroforestry system under 5-year-old albizia stand is still good and intensive, creating work, improving social welfare, local community opinion change into positive perceptions for forestry development, forest protection, forest fire prevention, reducing rapid forest degradation and environmental quality conservation of forest areas.

scholarly journals Comparative Study Between ATOMES Novels, NOVOSECT SC21®, ATO BED BUG® and NEO-BOOST® as a Bio-organic Solution in Managing Tomato Open Field Plantation in Hrajel Area in Lebanon

2021 ◽  
Vol 13 (8) ◽  
pp. 1
Author(s):  
Dalida Darazy ◽  
Elias Zgheib ◽  
Johnny Nehme ◽  
Marwan Dagher ◽  
Dani Fadel
Keyword(s):  
Block Design ◽  
Larval Mortality ◽  
Alternaria Solani ◽  
Tuta Absoluta ◽  
Liriomyza Trifolii ◽  
Mortality Level ◽  
Bed Bugs ◽  
Randomized Block Design ◽  
Significant Difference ◽  
Negative Impacts

The increasing use of chemical insecticides has adversely effected the environment and increased insect resistance. Biopesticides have been noticed the potential to be an excellent alternative to chemicals to reduce the negative impacts to human health and the environment. Tomato (Lycopersicon esculentum) is the second most important vegetable crop worldwide due to its nutritional importance. The effect of NOVOSECT SC21® (0.5 L/200 L), ATO BED BUGS® (1 L/200 L) and NEO-BOOST® (1 kg/200 L) against Tuta absoluta, Liriomyza trifolii and Alternaria solani was studied. A complete randomized block design (CRBD) was used with three replications, three treatments and one control in Hrajel area in Lebanon in the summer of 2020. We evaluated the level of infestation and larval mortality level of Tuta absoluta, Liriomyza trifolii and Alternaria solani infection 24, 48 and 72 hr after the application. Results showed that NOVOSECT SC21® (Mix of metabolites of the Bacillus F.D. 777) was the most efficient in decreasing the infestation and inducing larval mortality level of T. absoluta and L. trifolii and the fungal infection induced by A. solani with significant difference with time, followed respectively by ATO BED BUGS® and finally NEO-BOOST®.

scholarly journals Effectiveness of Diflubenzuron and Bacillus thuringiensis Against Gypsy Moth Populations

1997 ◽  
Vol 14 (3) ◽  
pp. 135-140 ◽  
Author(s):  
Kevin W. Thorpe ◽  
Richard L. Ridgway ◽  
Ralph E. Webb
Keyword(s):  
Bacillus Thuringiensis ◽  
Population Density ◽  
Gypsy Moth ◽  
Mass Density ◽  
Larval Mortality ◽  
Larval Density ◽  
Egg Mass ◽  
Percent Reduction ◽  
Moth Population ◽  
Oak Trees

Abstract Aerial applications of Bacillus thuringiensis Berliner subsp. kurstaki (74.1 billion international units/ha per application; single and double applications), diflubenzuron [69 g (ai)/ha], and no treatment were evaluated. Treatment effects were estimated from frass collections, defoliation, counts of pupae under burlap, and egg-mass counts. Estimates of larval density in the canopy 20 days after treatment ranged from 318.3 to 55.5 larvae per m² in the control- and diflubenzuron-treated plots, respectively. Larval density was reduced in all treatments, and was lowest in the plots treated with diflubenzuron and two applications of B. thuringiensis. Population density rapidly declined in the control plots, and by June 20, when larvae were predominantly in the fifth and sixth instars, no significant differences in larval density were detected among the treatments. Significantly less defoliation occurred to oak trees in the treated plots, but no differences were detected among the spray treatments. Counts of pupae under burlap, postseason egg-mass counts, and percent reduction in egg-mass density did not differ significantly among treatments or versus controls. These results suggest that diflubenzuron and double B. thuringiensis treatments caused higher levels of larval mortality than occurred with a single B. thuringiensis application, but that with a naturally declining gypsy moth population the final levels of damage were the same under all treatments. North. J. Appl. 14(3):135-140.

scholarly journals Effects of phenological synchronization on caterpillar early-instar survival under a changing climate

2018 ◽  
Vol 48 (3) ◽  
pp. 247-254 ◽  
Author(s):  
Emma Despland
Keyword(s):  
Population Dynamics ◽  
Host Plants ◽  
Larval Mortality ◽  
Mortality Rates ◽  
Chemical Defenses ◽  
Population Fluctuations ◽  
Density Dependent ◽  
Early Instar ◽  
Species Specific ◽  
Very High

Early-instar caterpillars experience very high and often very variable mortality; if it is density dependent, it can be a key factor in outbreak dynamics. Plant physical and chemical defenses can be extremely effective against young caterpillars, even of specialists. Phenological asynchrony with host plants can lead to dispersal and mortality in the early instars and increased predation or poor nutrition in later instars. Predation on early-instar larvae (including cannibalism) can be extremely high, parasitism appears generally low, and pathogens acquired early in larval development can lead to high mortality in later stadia. Four well-studied species reveal very different roles of early-instar mortality in population dynamics. In spruce budworm and gypsy moth, early-instar mortality rates can be very high; they do not drive outbreak cycles because density dependence is weak, but can modulate cycles and contribute to outbreak size and duration. For the autumnal moth, early-instar survival depends on host plant synchrony, but may or may not be density dependent. For monarch butterflies, the relative importance of larval mortality rates in population dynamics remains unclear. Tritrophic interactions between herbivores, host plants, natural enemies, and microbes play complex and species-specific roles in early-instar ecology, leading to emergent dynamics in population fluctuations. The phenology of these relationships is often poorly understood, making their responses to climate change unpredictable.

scholarly journals Challenges in chemical management of soybean looper (Chrysodeixis includes) using several insecticides

2019 ◽  
pp. 1723-1730 ◽  
Author(s):  
Clerison R. Perini ◽  
Jonas A. Arnemann ◽  
Lucas de A. Cavallin ◽  
Gabriel A. Guedes ◽  
Rafael P. Marques ◽  
...  
Keyword(s):  
High Mortality ◽  
Linear Models ◽  
Block Design ◽  
Larval Density ◽  
Type I ◽  
Block Designs ◽  
Randomized Block Design ◽  
Soybean Leaf ◽  
Soybean Looper ◽  
Randomized Block Designs

Soybean looper, Chrysodeixis includens (Walker, [1858]) (Lepidoptera: Noctuidae), is the most important caterpillar pest in Brazil due to its high tolerance to insecticides and control failures that have been reported in fields. Based on this, we assessed the performance of several insecticides against C. includens on soybean over three seasons (2014, 2015, and 2016), performing four experiments in southern Brazil. Experiments I / 2014, II / 2015, III / 2016 were carried in completely randomized block designs with eight insecticides. Experiment IV / 2016 was arranged in completely randomized block design in an 8 x 2 factorial arrangement, eight insecticides x two spraying time. Mortality of small (< 1.5 cm) and large (> 1.5 cm) soybean looper larvae was assessed with a vertical beat cloth, sampling in each plot 1.0 m2 at 3, 7 and 10 days after spray. Percentage of defoliation injury was assessed visually comparing to a scale of soybean leaf injury in experiment IV / 2016. Data were subjected to one-way (type I SS) analysis of variance (ANOVA) using the general linear models. The insecticides indoxacarb and chlorfenapyr had consistently high mortality upon small and large larvae of C. includens. Spinosyn, spinosad and spinetoram insecticides showed higher effect over small larvae (< 1.5 cm) than large (> 1.5 cm). Number of spraying was significant for spinetoram and indoxacarb that increased mortality of large larvae (from 4.50 to 2.75 and from 3.75 to 0.87 larvae m-2, respectively) and reduced defoliation injury significantly (from 22.5% to 9.3% and from 14.5% to 3.3%, respectively) with two applications. The treatment chlorfluazuron+acephate showed low defoliation injury in 2016 but did not affect larval density. Chlorfenapyr showed reduced defoliation (3.0%) and low larvae density (1.37 larvae m-2) with only one application. Spinosyns have satisfactory control of small larvae and indoxacarb and chlorfenapyr show high mortality of both sizes, small and large larvae. Therefore, we recommend that 7 days from the first one, a second application should be considered for indoxacarb, and spinetoram to achieve higher mortality. Considering our results, we demonstrate that the satisfactory control of soybean looper larvae is difficult to achieve with most chemical insecticides. It needs a more accurate management strategy of C. includens in soybeans.

Discrimination of intra- and inter-specific forage quality by collared pikas (Ochotona collaris)

2008 ◽  
Vol 86 (6) ◽  
pp. 456-461 ◽  
Author(s):  
S. F. Morrison ◽  
D. S. Hik
Keyword(s):  
Water Content ◽  
Block Design ◽  
Ochotona Collaris ◽  
Randomized Block Design ◽  
Selection Decisions ◽  
Nutritional Characteristics ◽  
Forage Species ◽  
Specific Variation ◽  
Species Specific ◽  
Selection Of

The specific nutritional characteristics by which herbivores evaluate their foraging options are complex. We experimentally manipulated the crude protein and water content of two forage species ( Carex consimilis Holm. (= Carex bigelowii Torr. ex Schwein.) and Polygonum bistorta L.) commonly cached by collared pikas ( Ochotona collaris (Nelson, 1893)) to determine their influence on inter- and intra-specific forage selection. Preference data were collected for 27 pikas using cafeteria-style feeding trials in a randomized block design. A three-way interaction (species × protein × water) suggested that pikas made conditional forage selection decisions while caching these plants. The interaction was driven by greater selection for fresh rather than dried C. consimilis when both were not fertilized. Water content had no effect on the selection of either fertilized C. consimilis or fertilized P. bistorta. Overall, our results indicate that pikas made subtle decisions about their selection of vegetation during caching, based on variation in nitrogen and water content in addition to species-specific selection criteria. Further, our results imply that tests of foraging theory may need to consider intra-specific variation in forage characteristics, as well as inter-specific ranking of forage species.

EFFECTS OF DENSITY ON THE PROPORTION OF MALE AND FEMALE PUPAE IN GYPSY-MOTH POPULATIONS

1985 ◽  
Vol 117 (5) ◽  
pp. 535-539 ◽  
Author(s):  
Yves Mauffette ◽  
Luc Jobin
Keyword(s):  
Population Dynamics ◽  
Linear Regression ◽  
Sex Ratio ◽  
Gypsy Moth ◽  
Lymantria Dispar ◽  
Larval Density ◽  
Dynamic State ◽  
Regression Analyses ◽  
Important Indicator ◽  
Male And Female

AbstractThe numbers of larvae and pupae of the gypsy moth, Lymantria dispar L., were monitored in southwestern Quebec from June through August 1980 at 13 sites. In 10 sites, the proportion of male pupae was significantly different from an expected proportion of 0.5. Linear-regression analyses of the proportion of male pupae on larval density showed a significant increase in the number of male pupae with increasing larval density. Changes in the sex ratio could be an important indicator of the dynamic state of a population, and should be considered in modeling the population dynamics of gypsy moth.

Developing Information-Processing Skills through Structured Activities with a Computerized File-Management Program

1987 ◽  
Vol 3 (3) ◽  
pp. 355-375 ◽  
Author(s):  
Charles S. White
Keyword(s):  
Information Processing ◽  
Computer Literacy ◽  
Block Design ◽  
Verbal Ability ◽  
Thinking Skills ◽  
Management Program ◽  
File Management ◽  
Structured Activities ◽  
Randomized Block Design ◽  
The Difference

Considerable attention has been focused recently on the development of thinking skills among pre-college students. Advocates of computer-based education have suggested that computerized file-management programs can enhance thinking skills, especially those involving the identification, retrieval, organization and evaluation of information required for effective problem solving. Employing a randomized block design, a two-treatment experiment to test this claim was devised, involving fourteen paired classrooms and 665 seventh- through twelfth-grade students. The treatments and treatment materials were adapted from commercially produced social studies curriculum data bases. The computer-using/structured-activities treatment group achieved significantly higher mean scores than the non-computer-using/non-structured-activities group on a 14-item power test of selected information-processing skills (effect size = .27). The difference persisted when verbal ability and grade level were controlled. Suggestions for further research are proposed, and implications for instructional methodology, curriculum development, and conceptions of pre-college computer literacy are discussed.

scholarly journals Using Crop Rotation to Control Meloidogyne hapla Chitwood and Improve Marketable Carrot Yield

HortScience ◽  
1996 ◽  
Vol 31 (1) ◽  
pp. 106-108 ◽  
Author(s):  
G. Bélair ◽  
L.E. Parent
Keyword(s):  
Crop Rotation ◽  
Weed Management ◽  
Block Design ◽  
Organic Soil ◽  
Management Program ◽  
Meloidogyne Hapla ◽  
Root Knot Nematode ◽  
Population Densities ◽  
The Third ◽  
Randomized Block Design

The influence of various crop rotations on population densities of Meloidogyne hapla, the northern root-knot nematode, and subsequent carrot yields was studied in organic soil under field conditions. Seven 3-year sequences with barley (Hordeum vulgare L.), carrot (Daucus carota L.), onion (Allium cepa L.), or weedy fallow, all with carrot as the third-year crop, were replicated six times in a completely randomized block design. Carrot monoculture, two seasons of weedy fallow, or carrot followed by onion resulted in high M. hapla population densities and severe root damage on carrot the third year. Barley followed by onion or onion followed by barley harbored low M. hapla population densities and provided the highest yields, with 56.8 and 47.2 t marketable carrots/ha, respectively, compared to 2.2 t·ha–1 in the carrot monoculture. A single crop of barley reduced nematode population densities and provided 88% and 73% marketable carrot roots in the subsequent years. High M. hapla population densities and the high proportion of culls recorded in plots in weed fallow emphasize the importance of an effective weed management program for successfully using crop rotation against root-knot nematode in muck-grown carrot.

Influence of Bacillus thuringiensis application timing on population dynamics of gypsy moth in Mediterranean cork oak forests

2019 ◽  
Vol 76 (3) ◽  
pp. 1103-1111
Author(s):  
Roberto Mannu ◽  
Arturo Cocco ◽  
Pietro Luciano ◽  
Andrea Lentini
Keyword(s):  
Population Dynamics ◽  
Bacillus Thuringiensis ◽  
Gypsy Moth ◽  
Cork Oak ◽  
Oak Forests ◽  
Application Timing
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