Field Cage Evaluation of Predators of the Soybean Looper, Pseudoplusia includens (Lepidoptera: Noctuidae) 12

1980 ◽  
Vol 9 (3) ◽  
pp. 315-317 ◽  
Author(s):  
David B. Richman ◽  
Robert C. Hemenway ◽  
Willard H. Whitcomb
Keyword(s):  
Pseudoplusia Includens ◽  
Field Cage ◽  
Soybean Looper ◽  
Lepidoptera Noctuidae

SEASONAL INCIDENCE OF METEORUS AUTOGRAPHAE1 ON SOYBEAN LOOPER2 LARVAE ON SOYBEAN IN SOUTH CAROLINA, AND THE INFLUENCE OF HOST DENSITY ON PARASITIZATION3

1986 ◽  
Vol 21 (4) ◽  
pp. 338-345 ◽  
Author(s):  
J. F. Grant ◽  
M. Shepard
Keyword(s):  
South Carolina ◽  
Host Density ◽  
Pseudoplusia Includens ◽  
Cylindrical Container ◽  
Seasonal Incidence ◽  
Percent Parasitism ◽  
Soybean Looper ◽  
Lepidoptera Noctuidae

The seasonal incidence of Meteorus autographae Muesebeck (Hymenoptera: Braconidae) on larvae of the soybean looper, Pseudoplusia includens (Walker) (Lepidoptera: Noctuidae), in soybean fields in South Carolina was monitored at two locations during 1981, 1982, and 1983. In most instances, parasitism of soybean looper larvae by M. autographae was detected 7 to 14 days after soybean looper larvae were first found in the fields. During this three-year study, maximum parasitism of soybean looper larvae by M. autographae within a season ranged from 4.6 to 19.8%. In the laboratory, numbers of hosts parasitized per 24 hours by M. autographae increased with each successive increase in host density. At a host density of 40 larvae per 1.75-liter cylindrical container, an average of 26 hosts were parasitized by one M. autographae during 24 hours. Percent parasitism remained about the same (64 – 70%) at all host densities.

COMPARISON OF SOYBEAN LOOPER (LEPIDOPTERA: NOCTUIDAE) POPULATIONS IN SOYBEAN AND COTTON/SOYBEAN AGROECOSYSTEMS

1986 ◽  
Vol 21 (1) ◽  
pp. 21-25 ◽  
Author(s):  
R. Mark Beach ◽  
James W. Todd
Keyword(s):  
Larval Density ◽  
Pseudoplusia Includens ◽  
Study Results ◽  
Cotton Fields ◽  
Southern Georgia ◽  
Soybean Looper ◽  
Lepidoptera Noctuidae

During 3 years, soybean fields in southern Georgia were sampled for larval soybean looper (SBL), Pseudoplusia includens Walker. Soybean fields were sampled from 2 area types: areas in which cotton and soybean were both grown and areas where soybean was grown in the absence of cotton. Average larval density during the 3-year period ranged from 0.5 to 93.9 larvae/50 sweeps in cotton + soybean areas and from 0.0 to 7.1 larvae/50 sweeps in soybean only areas. Populations of SBL larvae were significantly (P=0.05) greater on soybean in cotton + soybean areas as opposed to soybean only areas on the majority of sample dates over the 3 year study. Results of surveys indicate that soybean fields planted near cotton fields are at greater risk of experiencing economically injurious populations of SBL larvae.

Soybean Looper (Lepidoptera: Noctuidae) Oviposition Preference Relative to Plant Development in Soybean and Cotton

1992 ◽  
Vol 27 (3) ◽  
pp. 217-223 ◽  
Author(s):  
C. M. Felland ◽  
R. P. Porter ◽  
H. N. Pitre
Keyword(s):  
Plant Development ◽  
Oviposition Preference ◽  
Growing Season ◽  
Pseudoplusia Includens ◽  
Canopy Closure ◽  
Oviposition Choice ◽  
Phenological Stages ◽  
Egg Density ◽  
Soybean Looper ◽  
Lepidoptera Noctuidae

Oviposition choice by soybean looper, Pseudoplusia includens (Walker), of soybean and cotton in two phenological stages was tested in field cages to determine relative oviposition preference for these two crops in a situation similar to early- to mid-season cropping conditions in Mississippi. Moths were released into field cages enclosing four contiguous rows for each of two treatments, and egg density per m of row was determined after the second night. Test 1 paired blooming cotton (planted 25 May) with either blooming (23 June) or vegetative (11 July) soybean. Relative to blooming cotton with 81.1% canopy closure, blooming soybean with 78% canopy closure received 2.6-fold greater oviposition, while vegetative soybean with 41% canopy closure received only 0.24-times the eggs as blooming cotton. Test 2 compared oviposition on the two soybean classes in the absence of cotton. Here, 11.2-fold more eggs were oviposited on blooming soybean than on vegetative soybean. Test 3 paired blooming soybean with either blooming or pre-bloom cotton (planted 23 June). Relative to soybean, the pre-bloom cotton with 68.7% canopy closure received 1.6-fold more eggs than blooming cotton, although neither cotton treatment received as many eggs as blooming soybean. This study suggests that the importance of cotton as a host of soybean looper declines as the crop growing season advances.

Selective Feeding of Soybean Looper (Lepidoptera: Noctuidae) on Meridic Diet with Different Concentrations of the Bacillus thuringiensis Cry1Ac Protein

2004 ◽  
Vol 39 (2) ◽  
pp. 243-250
Author(s):  
Jeffrey Gore ◽  
John J. Adamczyk
Keyword(s):  
Bacillus Thuringiensis ◽  
The Other ◽  
Pseudoplusia Includens ◽  
Selective Feeding ◽  
Choice Assay ◽  
Soybean Looper ◽  
Lepidoptera Noctuidae ◽  
Cry1ac Protein ◽  
Meridic Diet

The ability of soybean loopers, Pseudoplusia includens, (Walker), to selectively feed on meridic diet with different concentrations of Cry1Ac was investigated in a choice assay. Neonates selected non-treated meridic diet and diet with concentrations of Cry1Ac ranging from 0.1 to 1.0 μg/mL for feeding compared to diet with Cry1Ac concentrations of 5.0 and 10.0 μg/mL. Averaged across rating periods, means of 11.9 to 17.6% of larvae were observed feeding on diet with Cry1Ac concentrations ranging from 0.0 to 1.0 μg/ml, compared to 3.4% on diet with Cry1Ac concentrations of 5 μg/mL and 4.3% at 10 μg/mL. In a no-choice study, concentrations ranging from 0.1 to 1.0 μg/mL produced 4.3 to 40.8% mortality in soybean looper; while, concentrations of 5.0 μg/mL produced 58.5% mortality and 10.0 μg/mL produced 90.8% mortality. Also, diet with Cry1Ac concentrations of 5.0 and 10.0 μg/mL delayed the development of soybean looper larvae compared to diet with the other concentrations of Cry1Ac. Based on results of this study, soybean loopers can select diet with concentrations of Cry1Ac that result in low (<50%) levels of mortality.

The influence of behaviour modifying chemicals on mating success of the red bollworm Diparopsis castanea Hmps. (Lepidoptera, Noctuidae) in Malawi

1976 ◽  
Vol 66 (2) ◽  
pp. 279-300 ◽  
Author(s):  
R. J. Marks
Keyword(s):  
Sex Pheromone ◽  
Sexual Attraction ◽  
Practical Method ◽  
Pheromone Trap ◽  
Cotton Field ◽  
Field Cage ◽  
Synthetic Sex Pheromone ◽  
Trap Catches ◽  
First Time ◽  
Lepidoptera Noctuidae

AbstractThe synthetic sex pheromone (dicastalure) of the red bollworm of cotton, Diparopsis castanea Hmps., in Central and Southern Africa, and an inhibitor of male sexual attraction (trans-9-dodecenyl acetate,=IIA), were used in an enclosed 0·2 ha cotton field-cage to reduce successful female matings. Over one month dicastalure at 21·0 and 42·3 g/ha produced average reductions in mating of 47·9% and 72·5% respectively and 37·9 g IIA/ha produced an overall reduction in mating of 71·5%, or 79·5% in released moth populations, over the same period. The proportion of virgin females present in disruption situations was significantly greater than in untreated populations and was density-independent for moth populations of up to 2 200/ha. The proportion of fertile eggs in disruption situations was correspondingly reduced to 30·2% from an average of 67·9% in control cycles. Reduction in sex pheromone trap catches is an unsatisfactory indicator of the extent to which males are prevented from inseminating females and considerably over-estimates the true degree of disruption. This is the first time that a naturally occurring inhibitor has been used successfully to disrupt mating in a field population of insects and it indicates the potential of the method for the control of high density pest populations in cotton. However, use of polyethylene dispensing mechanisms similar to those used in the field-cage disruption experiments would be unsuitable as a practical method of dispensing behaviour modifying chemicals and it is suggested that, for suitably controlled release of such chemicals, currently available microencapsulation technology offers the best prospects.

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