ECONOMIC INJURY LEVELS FOR THE RED SUNFLOWER SEED WEEVIL (COLEOPTERA: CURCULIONIDAE) INFESTING OILSEED SUNFLOWER

1995 ◽  
Vol 127 (4) ◽  
pp. 561-568 ◽  
Author(s):  
Chengwang Peng ◽  
Gary J. Brewer
Keyword(s):  
Sunflower Seed ◽  
Oil Content ◽  
Economic Status ◽  
Field Studies ◽  
Economic Injury Level ◽  
Economic Injury ◽  
Smicronyx Fulvus ◽  
The Cost ◽  
Single Larva ◽  
Adult Weevil

AbstractThe control of the red sunflower seed weevil, Smicronyx fulvus LeConte, relies on the use of insecticides. An economic injury level is essential to the judicious deployment of insecticidal control. Field studies were conducted in 1992 and 1993 to quantify the weight loss and oil content loss of damaged kernels as a result of larval infestation and the relationship between the adult weevil population and the subsequent number of damaged achenes. We found that for each weevil sampled in plant stages R5.0–5.3, 26.88 damaged achenes resulted. Damaged kernels lost an average of 9.86 ± 2.36 mg (mean ± SD) per kernel, approximately equal to the amount consumed by a single larva. The oil content loss in damaged kernels was 3.34%. Economic injury levels were calculated as a function of the cost of controls, the market value, and the plant population density. Use of adult weevil counts when most plants in the fields are in plant stages R5.0–5.3 are recommended for calculating economic status.

scholarly journals Determination of economic injury levels of Helicoverpa armigera (Hubner) in chickpea

1970 ◽  
Vol 33 (4) ◽  
pp. 555-563 ◽  
Author(s):  
MA Zahid ◽  
MM Islam ◽  
MH Reza ◽  
MHZ Prodhan ◽  
M Rumana Begum
Keyword(s):  
Helicoverpa Armigera ◽  
Threshold Level ◽  
Damage Potential ◽  
Cropping Season ◽  
Pod Borer ◽  
Economic Injury ◽  
Helicoverpa Armígera ◽  
The Cost ◽  
Single Larva

Chickpea pod borer Helicoverpa armigera (Hubner) is considered to be one of the major pests of chickpea. The damage potential and economic threshold level for Helicoverpa armigera larvae on chickpea crop were worked out. On an average, single larva per m row reduced the yield to the extent of 155 kg/ha and 157 kg/ha in 2004-05 and 2005-06 cropping season, respectively. The ratio of the value of yield saved to the cost of insecticide application at one larva per m row was 1.06 and 1.12 in 2004-05 and 2005-06, respectively. EILs for Helicoverpa armigera were determined as 12 and 0.95 per m row and ETLs was at 09 and 0 73 larvae per m row in 2004-05 and 2005 - 06, respectively. Key Words: Economic injury, chickpea, pod borer doi: 10.3329/bjar.v33i4.2288 Bangladesh J. Agril. Res. 33(4) : 555-563, December 2008

Trap cropping to manage the red sunflower seed weevil in oilseed sunflower

1995 ◽  
Vol 10 (4) ◽  
pp. 184-187 ◽  
Author(s):  
Gary J. Brewer ◽  
Gene Schmidt
Keyword(s):  
South Dakota ◽  
Sunflower Seed ◽  
Insect Damage ◽  
Economic Costs ◽  
Early Maturing ◽  
Trap Cropping ◽  
Major Pest ◽  
Smicronyx Fulvus ◽  
The Cost ◽  
North And South

AbstractThe red sunflower seed weevil,Smicronyx fulvusLeConte, is a major pest of sunflower in North and South Dakota and Minnesota. Typically, insecticides are used to reduce oviposition and prevent economically damaging larval populations from developing. In a test of a reduced-pesticide alternative, we planted early maturing sunflower in the margins around commercial fields of oilseed sunflower. The margins flowered earlier than the field interiors and acted as a trap for the red sunflower seed weevil. They were treated with an insecticide while the trap rows were blooming and before the field interior began to flower. Conventional fields entirely treated with insecticide served as checks. We compared the trap and check fields with regard to yield, the fraction of larval-damaged seeds, and economic costs (insect damage and the cost of insecticide materials and application). Yield and larval damage of seeds were comparable between check and trap fields. However, the economic costs of weevil control in the check fields was greater than in the trap fields. Trap cropping is a recommended strategy for the red sunflower seed weevil, especially where economically damaging populations of the weevil are expected.

scholarly journals Determination of Economic Injury Levels of Maruca vitrata in Mungbean

1970 ◽  
Vol 6 (1) ◽  
pp. 91-97 ◽  
Author(s):  
MA Zahid ◽  
MM Islam ◽  
MR Begum
Keyword(s):  
Key Words ◽  
Maruca Vitrata ◽  
Economic Threshold ◽  
Damage Potential ◽  
Insecticide Application ◽  
Economic Injury ◽  
Cropping Seasons ◽  
The Cost ◽  
Single Larva

Maruca vitrata is considered to be one of the major pests of mungbean. The damage potential and economic threshold levels of Maruca vitrata larvae on mungbean were worked out at ARS, BARI, Burirhat, Rangpur during rabi 2005-2006 and 2006-2007. On an average single larva per m row reduced the yield to the extent of 154 kg/ha and 106 kg/ha in 2005-2006 and 2006-2007 cropping seasons, respectively. The ratio of the value of yield saved to the cost of insecticide application at one larva per m row in 2005-2006 was 1.45 and same in 2006-2007 was 1.34. EIL for Maruca vitrata were determined as 1.0 and 1.16 larvae per m row in 2005-2006 & 2006-2007respectively. ET value was determined from EILs and those were found to be at 0.75 and 0.87 larvae per m row in 2005-2006 & 2006-2007 respectively. On the basis of means of two years the EIL and ETL values of Maruca vitrata were 1.08 & 0.81 larvae per m row, respectively. Key words: ETL, EIL, Maruca vitrata, Mungbean. doi:10.3329/jard.v6i1.1662 J Agric Rural Dev 6(1&2), 91-97, June 2008

Renovating the View of Cost Sharing for the Underground Low Voltage Cable Projects in Hanoi

2019 ◽  
Vol 35 (5E) ◽  
Author(s):  
Pham Thi Thu Ha ◽  
Phan Dieu Huong
Keyword(s):  
Willingness To Pay ◽  
Cost Sharing ◽  
Low Voltage ◽  
Power Grid ◽  
Field Studies ◽  
Power Industry ◽  
Well Field ◽  
The Subject ◽  
Sharing Responsibility ◽  
The Cost

Underground power grid projects in Hanoi is so urgent that it requires immediate implementation. To synchronously and quickly implement the underground power grid projects, people in charge should not follow the outdated perspectives of just including the power industry, but also need to call for the support and cost sharing responsibility from consumers. This paper aims at approaching the subject both from the producers and consumers’ perspectives to together sharing the cost of putting the power grid underground not only in Hanoi but other metropolitans in Vietnam as well. Field studies (including 104 families) at Hoan Kiem District, Hanoi and CBA method were applied to investigate the willingness to pay (WTP) level of consumers to share the cost with the power industry for the underground power grid projects in Hanoi. The overview of the results shows that cost for the underground power grid in Hoan Kiem District ranging from 30,000 VND/household/month to 46,000VND/household/month. On the other hand, the willingness to pay of a typical household of four people within Hoan Kiem District ranges from 17,000VND/month to 24,000VND/month, with the most favorable method of annual payment within a detailed timeline.

scholarly journals Perception and Use of Economic Thresholds Among Farmers and Agricultural Professionals: A Case Study on Soybean Aphid in Minnesota

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Natalie Hoidal ◽  
Robert L Koch
Keyword(s):  
Soybean Aphid ◽  
Educational Outreach ◽  
Economic Injury Level ◽  
Economic Thresholds ◽  
Foundational Principle ◽  
Economic Injury ◽  
Fundamental Misunderstanding ◽  
The Difference ◽  
Commercial Pesticide ◽  
Agricultural Professionals

Abstract Economic thresholds (ETs) are a foundational principle of integrated pest management but are not always widely accepted by farmers and agricultural professionals. This article reports on a survey of Minnesota farmer and agricultural professional perceptions of the ET for soybean aphid, Aphis glycines Matsumura (Hempitera: Aphididae). We discuss insights for Extension programs on how to frame the importance of thresholds and teach stakeholders to use them effectively. Key takeaways include farmers and agricultural professionals often worry about combined effects of insect, disease, and physiological pressures, whereas effects of interactions with these other stressors are seldom discussed in educational outreach. Across groups, there is a fundamental misunderstanding about the difference between ETs and economic injury level. Many survey participants reported believing in the ET but lacked the time and capacity to fully implement it. Sales agronomists and farmers were the least likely groups to trust the university-determined soybean aphid ET, whereas commercial pesticide applicators and independent consultants were the most likely groups to trust it. Based on these results, we recommend adapting communication about ETs based on the target audience to address common misconceptions and barriers to ET use that are unique to each group.

Fatty Acid Data and Crop Surveys Indicate Sources of Red Sunflower Seed Weevil (Coleoptera: Curculionidae), Populations and Suggest Strategies for Management

2020 ◽  
Author(s):  
Jarrad R Prasifka ◽  
Beth Ferguson ◽  
James V Anderson
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Sunflower Seed ◽  
Cultural Practices ◽  
High Oleic ◽  
Fatty Acid Data ◽  
Smicronyx Fulvus ◽  
Combined Data ◽  
Fatty Acid Compositions

Abstract The red sunflower seed weevil, Smicronyx fulvus L., is a univoltine seed-feeding pest of cultivated sunflower, Helianthus annuus L. Artificial infestations of S. fulvus onto sunflowers with traditional (<25% oleic acid), mid-oleic (55–75%), or high oleic (>80%) fatty acid profiles were used to test if fatty acids could be used as natural markers to estimate the proportion of weevils developing on oilseed sunflowers rather than wild Helianthus spp. and confection (non-oil) types. Oleic acid (%) in S. fulvus confirmed the fatty acid compositions of mature larvae and weevil adults reflected their diets, making primary (oleic or linoleic) fatty acids feasible as natural markers for this crop-insect combination. Oleic acid in wild S. fulvus populations in North Dakota suggests at least 84 and 90% of adults originated from mid-oleic or high oleic sunflower hybrids in 2017 and 2018, respectively. Surveys in 2017 (n = 156 fields) and 2019 (n = 120 fields) extended information provided by S. fulvus fatty acid data; no significant spatial patterns of S. fulvus damage were detected in samples, damage to oilseed sunflowers was greater than confection (non-oil) types, and the majority of damage occurred in ≈10% of surveyed fields. Combined, data suggest a few unmanaged or mismanaged oilseed sunflower fields are responsible for producing most S. fulvus in an area. Improved management seems possible with a combination of grower education and expanded use of non-insecticidal tactics, including cultural practices and S. fulvus-resistant hybrids.

scholarly journals Determining the critical period for weed control in high-yielding cotton using common sunflower as a mimic weed

2019 ◽  
Vol 33 (6) ◽  
pp. 800-807 ◽  
Author(s):  
Graham W. Charles ◽  
Brian M. Sindel ◽  
Annette L. Cowie ◽  
Oliver G. G. Knox
Keyword(s):  
Weed Control ◽  
Critical Period ◽  
Yield Loss ◽  
Field Studies ◽  
Growing Degree Days ◽  
Degree Days ◽  
Weed Density ◽  
High Level ◽  
The Cost ◽  
Planting Season

AbstractField studies were conducted over six seasons to determine the critical period for weed control (CPWC) in high-yielding cotton, using common sunflower as a mimic weed. Common sunflower was planted with or after cotton emergence at densities of 1, 2, 5, 10, 20, and 50 plants m−2. Common sunflower was added and removed at approximately 0, 150, 300, 450, 600, 750, and 900 growing degree days (GDD) after planting. Season-long interference resulted in no harvestable cotton at densities of five or more common sunflower plants m−2. High levels of intraspecific and interspecific competition occurred at the highest weed densities, with increases in weed biomass and reductions in crop yield not proportional to the changes in weed density. Using a 5% yield-loss threshold, the CPWC extended from 43 to 615 GDD, and 20 to 1,512 GDD for one and 50 common sunflower plants m−2, respectively. These results highlight the high level of weed control required in high-yielding cotton to ensure crop losses do not exceed the cost of control.

scholarly journals Effects from Early Planting of Late-Maturing Sunflowers on Damage from Primary Insect Pests in the United States

Helia ◽  
2016 ◽  
Vol 39 (64) ◽  
pp. 45-56 ◽  
Author(s):  
J. R. Prasifka ◽  
L. F. Marek ◽  
D. K. Lee ◽  
S. B. Thapa ◽  
V. Hahn ◽  
...  
Keyword(s):  
United States ◽  
North Dakota ◽  
Sunflower Seed ◽  
Insect Pests ◽  
The United States ◽  
Total Percentage ◽  
History Of ◽  
Smicronyx Fulvus ◽  
Sunflower Moth ◽  
Homoeosoma Electellum

AbstractDelayed planting is recommended to reduce damage from sunflower insect pests in the United States, including the sunflower moth, Homoeosoma electellum (Hulst) and banded sunflower moth, Cochylis hospes Walsingham. However, in some locations, planting earlier or growing later-maturing hybrids could improve yield or oil content of sunflowers which would partially offset any added costs from insect pests or their management. Because the abundance and distribution of some sunflower insects have changed since recommendations for delayed planting were developed, experimental plots were grown in 2012 and 2013 at sites in North Dakota, Nebraska, Iowa, and Illinois. Sunflowers were planted two to four weeks earlier than normal, including hybrids that flower two to three weeks later than elite commercial hybrids. The sum of seed damaged by sunflower moth, banded sunflower moth, and red sunflower seed weevil, Smicronyx fulvus LeConte, (i. e., total percentage) was influenced by location, but not the relative maturity of tested entries. However, when damage attributed solely to the red sunflower seed weevil was analyzed, more damaged seed were found for late-maturing entries in North Dakota and Nebraska. In addition to the trial data, current pest populations are lower than when delayed planting was first recommended and insecticide use during sunflower bloom is both common and effective. Together, these observations suggest factoring insect pests into planting time decisions may be unnecessary, except for areas with a history of problems with severe pests that cannot be managed using insecticides (e. g., sunflower midge, Contarinia schulzi Gagné).

Sign in / Sign up

Export Citation Format

Share Document