Plant Population, Planting Date and Cotton Variety Impact on Early Squaring and Development of a Trap Crop for Pink Bollworm (Lepidoptera: Noctuidae)

Bt cotton is used to control pink bollworm, Pectinophora gossypiella (Saunders), in much of the southwestern U.S. Where growers choose non-Bt varieties, early fruiting (squaring) Bt cotton might be used as a trap crop for pink bollworm control. Field tests were conducted in 1997 and 1998 to determine if early planting, varietal selection, and very low planting rates could increase early squaring. Cotton planted 4 April produced 6 mm squares approximately 11 days earlier than cotton planted 7 May. Low plant populations (4.3, 2.5 plants/m) did not result in more early squares, compared to recommended populations with 7.5 plants/m. Very dense populations with 18.4 vs. 9.4 plants/m produced more early squares/m despite fewer squares/plant. However, yield was reduced with planting rates above 7.5 plants/m. Some varieties produced more early-season squares than others, but differences were not always consistent. Paymaster 1215 produced significantly more early squares compared to two other short-season varieties (Deltapine 20B and Deltapine 50B) and the standard Acala 1517-95 in 1997, but not more than Acala 1517-95 in 1998. A mid-season variety (Paymaster 1560) produced the highest number of early squares in a comparison of ten Bt varieties in 1998. A non-Bt very short-season variety, Xpress, produced the earliest squares in 1997, more than 11 days earlier than Paymaster 1215 (a short-season variety), indicating that earlier squaring varieties of Bt cotton could be developed. These results indicate that early planting will provide the earliest squares but that variety and planting rate should be considered in developing a trap crop for pink bollworm control. Planting rate should be at least 7.5 plants/m but if yield is not a consideration could be as high as 18 plants/m.

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Relationship between cotton planting date and two bollworms associated with their natural enemies

Bulletin of the National Research Centre ◽

10.1186/s42269-020-00449-y ◽

2021 ◽

Vol 45 (1) ◽

Author(s):

Zakaria Abdelhalim Attia ◽

Laila Ebada ◽

Nasr Mohamed Abdelmaksoud

Keyword(s):

Natural Enemies ◽

Planting Date ◽

Pink Bollworm ◽

Cotton Yield ◽

Insect Infestation ◽

Highest Weight ◽

Spiny Bollworm ◽

The World ◽

The Mean ◽

Lepidoptera Noctuidae

Abstract Background Cotton is the most widespread, profitable non-food crop in the world. Egypt is one of the greatest countries in producing cotton (Gossypium hirsutum L.) in the world. Many pests attacked cotton which reduced the quality and quantity of the cotton yield such as pink bollworm (Pectinophora gossypiella) (Lepidoptera: Gelechiidae) and the spiny bollworm (Earias insulana) (Lepidoptera: Noctuidae). Results The insect infestation increased significantly by delaying planting date. The fewest numbers of pests attacked cotton recorded in the earliest planting date (March 23rd) with highest weight of cotton yield. The results showed that the mean rates of infestation with pink bollworm were (2.11, 3.5, 2.33 individuals/boll) for March 23rd, April 17th and May 6th, respectively, while the mean rates of infestation with bollworm were (1.60, 2.79, 1.67 individuals/boll) for March 23rd, April 17th and May 6th, respectively. Conclusion It was concluded that planting cotton as early as on March 23rd reduces the rate of infestation of E. insulana and P. gossypiella and increases the population of its natural enemies as well. Then, it is resulting a significant increase in the quality and quantity of the yield of cotton.

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Evaluation of Bt resistance in Helicoverpa zea (Lepidoptera: Noctuidae) strains using various Bt cotton plant tissues

Pest Management Science ◽

10.1002/ps.6611 ◽

2021 ◽

Author(s):

Dawson D. Kerns ◽

Fei Yang ◽

David L. Kerns ◽

Scott D. Stewart

Keyword(s):

Cotton Plant ◽

Helicoverpa Zea ◽

Plant Tissues ◽

Bt Cotton ◽

Bt Resistance ◽

Lepidoptera Noctuidae

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Bio-economics of Indian hybrid Bt cotton and farmer suicides

Environmental Sciences Europe ◽

10.1186/s12302-020-00406-6 ◽

2020 ◽

Vol 32 (1) ◽

Cited By ~ 1

Author(s):

Andrew Paul Gutierrez ◽

Luigi Ponti ◽

Keshav R. Kranthi ◽

Johann Baumgärtner ◽

Peter. E. Kenmore ◽

...

Keyword(s):

Pure Line ◽

High Density ◽

Production Costs ◽

Bt Cotton ◽

Indian States ◽

Value Capture ◽

South Central ◽

Viable Solution ◽

Farmer Suicides ◽

Short Season

Abstract Background The implementation of hybrid Bt cotton unique to India has been heralded as a grand success by government agencies, seed companies and other proponents, and yet yields have stagnated at low levels and production costs have risen 2.5–3-fold. The low-yield hybrid cotton system of India contributes thousands of farmer suicides to the annual national toll. Conceptual and methodological barriers have hindered bioeconomic analysis of the ecological and social sustainability of such cross-scale agro-ecological problems in time and geographic space, under global technology and climate change. As a paradigm shift, we use conceptually simple, parameter-sparse, theoretically based, mechanistic, weather-driven physiologically based demographic models (PBDMs) to deconstruct the bio-economics of the Indian cotton system. Results Our analysis of Indian hybrid cotton system explains some extant ecological and economic problems, and suggests a viable solution. Specifically, the model accurately captured the age-stage mass dynamics of rainfed and irrigated cotton growth/development and the interactions with the key pest pink bollworm across five south-central Indian states, and enabled identification of proximate bioeconomic factors responsible for low yield and their relationship to farmer suicides. The results are reinforced by analysis of Ministry of Agriculture annual state-level data. We explain why short-season, high-density non-GM cotton is a highly viable solution for Indian cotton farmers in rainfed and irrigated cotton areas of the five states, and possibly nationally. The transition from a theoretical bioeconomic construct to a real-world regional bioeconomic analysis proved seamless. Conclusions The hybrid long-season Bt technology for rainfed and irrigated cotton is unique to India, and is a value capture mechanism. This technology is suboptimal leading to stagnant yields, high input costs, increased insecticide use, and low farmer incomes that increase economic distress that is a proximate cause of cotton farmer suicides. The current GM Bt technology adds costs in rainfed cotton without commensurate increases in yield. Non-GM pure-line high-density short-season varieties could double rainfed cotton yield, reduce costs, decrease insecticide use, and help ameliorate suicides. The GM hybrid technology is inappropriate for incorporation in short-season high-density varieties.

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Influence of planting date and row covers on yields and crop values for bell peppers in Saskatchewan

Canadian Journal of Plant Science ◽

10.4141/cjps92-066 ◽

1992 ◽

Vol 72 (2) ◽

pp. 527-533 ◽

Cited By ~ 2

Author(s):

D. R. Waterer

Keyword(s):

Fruit Set ◽

Frost Damage ◽

Planting Date ◽

Early Planting ◽

Row Covers ◽

Crop Development ◽

Bell Peppers ◽

Premium Price ◽

Black Plastic ◽

Crop Maturity

In 1989 and 1990, bell peppers transplanted into the field in mid-May, late May or early June were grown with a black plastic soil mulch and no cover (NC) or under tunnels of perforated clear polyethylene (PT) or spunbonded polyester (ST). The ST treatment provided several degrees of frost protection, whereas the PT treatment appeared to increase the crop’s susceptibility to frost damage. Early planting had little effect on total fruit yields but did accelerate the harvest. In both years, the ST accelerated crop maturity and increased total fruit yields relative to the noncovered treatment. At times the PT improved crop development and increased fruit yields, but in many cases it reduced fruit yields relative to the noncovered treatment. By promoting early fruit set and development, early planting under the spunbonded row covers significantly enhanced the value of the crop, as early peppers command a premium price in Saskatchewan. Cumulative crop values for the PT treatments were generally similar to or poorer than those for the noncovered control.Key words: Bell pepper, Capsicum annuum, planting date, row covers, frost

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Impact of Bt cotton on the immune system and histology of the midgut of the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

Animal Biology ◽

10.1163/15707563-00002405 ◽

2013 ◽

Vol 63 (2) ◽

pp. 185-197 ◽

Cited By ~ 6

Author(s):

Franklin M. Cunha ◽

Valéria Wanderley-Teixeira ◽

Jorge B. Torres ◽

Álvaro A.C. Teixeira ◽

Thiago J.S. Alves ◽

...

Keyword(s):

Epithelial Cells ◽

Spodoptera Frugiperda ◽

Fall Armyworm ◽

Bt Cotton ◽

Contributing Factors ◽

Qualitative And Quantitative ◽

Cry1ac Toxin ◽

Cellular Immune ◽

Natural Tolerance ◽

Lepidoptera Noctuidae

Despite the efficiency of transgenic plants expressing Bacillus thuringiensis (Bt) toxins as insecticides against several lepidopterans, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is one species that presents low susceptibility to most Bt crops. This study investigated the effects of the Cry1Ac toxin expressed by Bt cotton in the midgut of S. frugiperda and its effects on the humoral and cellular immune responses. Three hypotheses were proposed and tested with contributing factors for the natural tolerance of S. frugiperda: (i) midgut regenerative cells are activated by the Cry1Ac toxin, and thus renew the epithelial cells damaged by the protein, (ii) Cry1Ac increased production of nitric oxide or phenoloxidase in the hemolymph, and (iii) there are qualitative and quantitative variations in the hemocyte levels of S. frugiperda. Caterpillars were reared using Bt cotton (Acala 90B) and non-Bt isolines (Acala 90), from the first to the fourth instar. The Bt cotton promoted elongation of the epithelial cells in the midgut of S. frugiperda caterpillars. Hence, evidence only supported the hypothesised increase of phenoloxidase (ii) and qualitative and quantitative differences in hemocyte levels (iii) in insects that were fed with Bt and non-Bt cotton. These parameters seem to explain the low susceptibility of S. frugiperda to Cry1Ac toxin and they are a viable set of responses for the evaluation of other xenobiotic factors.

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FIELD AND LABORATORY EVALUATION OF A SEX ATTRACTANT FOR THE WHITE CUTWORM, EUXOA SCANDENS (LEPIDOPTERA: NOCTUIDAE)

The Canadian Entomologist ◽

10.4039/ent1141101-11 ◽

1982 ◽

Vol 114 (11) ◽

pp. 1101-1103

Author(s):

D. G. R. McLeod ◽

T. Nagai ◽

A. N. Starratt ◽

C. Bonenfant ◽

E. W. Rud ◽

...

Keyword(s):

Sex Attractant ◽

Adult Population ◽

Field Tests ◽

Laboratory Evaluation ◽

Vegetable Crops ◽

Female Sex Pheromone ◽

Sex Attractants ◽

Monitoring Method ◽

Lepidoptera Noctuidae ◽

Insecticide Control

The white cutworm, Euxoa scandens (Riley), is a sporadic pest of tobacco in Quebec (Mailloux and Desrosiers 1978), asparagus in Michigan (A. L. Wells, pers. comm.), and other vegetable crops grown in light sandy soils (Beirne 1971). The immature larvae overwinter and cause serious damage when they resume feeding in the spring (Hudson and Wood 1930). Moths emerge and oviposit from late June until late July (McLeod and Dupré 1981). An efficient monitoring method utilizing the female sex pheromone would be an important aid in estimating the size and distribution of the adult population and would help in planning insecticide control. We report here some results of electroantennogram screening of potential sex attractants and the results of field tests of the most active of these.

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Status of resistance to Bt cotton in China: cotton bollworm and pink bollworm.

Bt resistance: characterization and strategies for GM crops producing Bacillus thuringiensis toxins ◽

10.1079/9781780644370.0015 ◽

2015 ◽

pp. 15-25 ◽

Cited By ~ 2

Author(s):

Y Gao ◽

C Liu ◽

Y Wu ◽

K Wu

Keyword(s):

Pink Bollworm ◽

Cotton Bollworm ◽

Bt Cotton

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Helicoverpa zea (Lepidoptera: Noctuidae) Preference for Plant Structures, and Their Location, Within Bt Cotton Under Different Nitrogen and Irrigation Regimes

Journal of Economic Entomology ◽

10.1093/jee/toz105 ◽

2019 ◽

Vol 112 (4) ◽

pp. 1741-1751

Author(s):

Lewis R Braswell ◽

Dominic D Reisig ◽

Clyde E Sorenson ◽

Guy D Collins

Keyword(s):

Helicoverpa Zea ◽

Resistance Management ◽

Larval Feeding ◽

Bt Cotton ◽

Larval Distribution ◽

Cotton Plants ◽

Small Plot ◽

Nitrogen Treatments ◽

Behavioral Resistance ◽

Lepidoptera Noctuidae

Abstract Helicoverpa zea Boddie is a common economic pest of cotton (Gossypium hirsutum L.), including transgenic cotton varieties that express Bacillus thuringiensis (Bt). Helicoverpa zea oviposition is similar in Bt and non-Bt cotton, but behavior of H. zea larvae can be different in the presence of Bt, with neonates moving away from terminals faster in single-toxin Bt than non-Bt cotton or avoiding Bt-treated diet in the lab. We quantified H. zea oviposition and larval distribution on structures within cotton plants in small plot experiments of Cry1Ac + Cry1F cotton for 2 yr under different irrigation and nitrogen treatments. More eggs were oviposited on plants receiving nitrogen application during 2016 and on leaves in the top section of irrigated plants during 2017, but other treatment effects on eggs or larvae were minimal. Helicoverpa zea eggs were most common on leaves in the top third of plants at position zero and middle section of cotton plants throughout the season, but some oviposition occurred on fruiting structures as well. First and second instars were more common on squares in the top section of plants during 2016 and bolls in the middle and lower sections during 2017 due to oviposition lower in the canopy during 2017. During both years, third through fifth instars were more common on bolls in the middle and lower section of plants closer to the main stem. These findings have resistance management implications as extended larval feeding on bolls could optimize nutrition, decrease Bt susceptibility, and potentially influence behavioral resistance.

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