Survival, Development, and Fecundity of the Pale Western Cutworm, Agrotis orthogonia Morr. (Lepidoptera: Noctuidae), After Starvation

1960 ◽  
Vol 92 (3) ◽  
pp. 184-188 ◽  
Author(s):  
L. A. Jacobson ◽  
P. E. Blakeley
Keyword(s):  
Food Supply ◽  
Fourth Instar ◽  
Feeding Period ◽  
Pupal Size ◽  
Lepidoptera Noctuidae

Larvae of the pale western cutworm, Agrotis orthogonia Morr., may be starved in the field by planned control (Seamans and Rock, 1945) or elimination of their food supply as a result of their own depredation. Starvation may occur at any time during the feeding period. Some effects of starvation on mortality, particularly in the early instars, have been reported (Jacobson, 1952). Larvae that were fed only two hours each day had an additional instar, developed more slowly, and were smaller (McGinnis and Kasting, 1959). Starvation during the fourth instar when the larvae were fed on various foods resulted in smaller pupae, and the size and fecundity of females were directly associated with pupal size (Jacobson and Blakeley, 1958).

The concentration of lamdacyhalothrin and its effect on the cutworm Agrotis segetum (Lepidoptera: Noctuidae)

1991 ◽  
Vol 81 (2) ◽  
pp. 143-145 ◽  
Author(s):  
B.W. Blair
Keyword(s):  
Fourth Instar ◽  
Synthetic Pyrethroid ◽  
Agrotis Segetum ◽  
Economic Plant ◽  
Initial Screening ◽  
Pest Damage ◽  
Plant Damage ◽  
Antifeedant Effect ◽  
Equivalent Rate ◽  
Lepidoptera Noctuidae

AbstractDuring initial screening of the synthetic pyrethroid lamdacyhalothrin (PP 321) at a concentration of 44 and 22 mg/l and applied as a 30 ml drench over each plant against third to fourth instar cutworms, Agrotis segetum (Denis & Schiffermüller) in microplots, few died but they did not damage the plants. Reducing the concentrations to 11 and 5.5 mg/l increased mortality and plant damage. When A. segetum were confined on soil treated with the insecticide at concentrations of 22, 11 and 5.5 mg/l and sprayed at an equivalent rate of 500 l/ha, they all died within one day. The higher concentrations appeared to have a repellent and/or antifeedant effect, and it has been possible to reduce the concentration of lamdacyhalothrin to 12.5 mg/l (≡5.6g a.i./ha) for the drench treatment without risking economic plant damage. For insecticides that have repellent and/or antifeedant properties, it should be possible to balance lower concentrations with adequate protection of plants from pest damage.

scholarly journals Reproductive potential of Spodoptera eridania (Stoll) (Lepidoptera: Noctuidae) in the laboratory: effect of multiple couples and the size

2016 ◽  
Vol 76 (2) ◽  
pp. 526-530 ◽  
Author(s):  
A. Specht ◽  
D. G. Montezano ◽  
D. R. Sosa-Gómez ◽  
S. V. Paula-Moraes ◽  
V. F. Roque-Specht ◽  
...  
Keyword(s):  
Reproductive Potential ◽  
Reproductive Parameters ◽  
Spodoptera Eridania ◽  
Adult Females ◽  
Controlled Conditions ◽  
Pupal Size ◽  
Lepidoptera Noctuidae

Abstract This study aimed to evaluate the effect of keeping three couples in the same cage, and the size of adults emerged from small, medium-sized and large pupae (278.67 mg; 333.20 mg and 381.58 mg, respectively), on the reproductive potential of S. eridania (Stoll, 1782) adults, under controlled conditions (25 ± 1 °C, 70% RH and 14 hour photophase). We evaluated the survival, number of copulations, fecundity and fertility of the adult females. The survival of females from these different pupal sizes did not differ statistically, but the survival of males from large pupae was statistically shorter than from small pupae. Fecundity differed significantly and correlated positively with size. The number of effective copulations (espematophores) and fertility did not vary significantly with pupal size. Our results emphasize the importance of indicating the number of copulations and the size of the insects when reproductive parameters are compared.

Development, Mortality from Starvation, and Oviposition of the Pale Western Cutworm, Agrotis orthogonia Morr. (Lepidoptera: Noctuidae), When Fed on Various Food Plants

1958 ◽  
Vol 90 (11) ◽  
pp. 650-653 ◽  
Author(s):  
L. A. Jacobson ◽  
P. E. Blakeley
Keyword(s):  
Food Supply ◽  
Previous Investigation ◽  
Food Plants ◽  
Rate Of Development ◽  
The One ◽  
Lepidoptera Noctuidae

When a crop has been destroyed by the pale western cutworm, Agrotis orthogonia Morr., one to two weeks may elapse before plants of the second seeding emerge. During this time the larvae may be starved or, at least, subjected to a suboptimum food supply. Frequently the second seeding may be of a different crop from the one that was destroyed.A previous investigation (Jacobson, 1952) showed that mortality of the starved larvae varied directly with temperature and inversely with size of larvae. Seamans and McMillan (1935) reported that, when the larvae were fed various foods, differences were found in the rate of development and survival.

Predation of Corn Earworm (Lepidoptera: Noctuidae) Eggs and Young Larvae by Orius insidiosus (Say) (Heteroptera: Anthocoridae) on Grain Sorghum in a Greenhouse

1994 ◽  
Vol 29 (1) ◽  
pp. 10-17 ◽  
Author(s):  
D. A. Jacobson ◽  
T. J. Kring
Keyword(s):  
Larval Density ◽  
Grain Sorghum ◽  
Corn Earworm ◽  
Fourth Instar ◽  
The Other ◽  
Orius Insidiosus ◽  
First Instar ◽  
Egg Density ◽  
Lepidoptera Noctuidae ◽  
Individual Adult

Individual adult, fourth- and second-instar Orius insidiosus (Say) were caged for 24 h on branches of grain sorghum panicles with combinations of 0, 2, or 4 corn earworm eggs and 0, 2, or 4 first instar earworms, excepting 0 eggs and 0 larvae. Individual adult O. insidiosus also were caged for 24 h with 2 second-instar corn earworms. In cages with corn earworm eggs and first instars, predation by all stages of O. insidiosus on one stage of corn earworm was not significantly influenced by the number of the other stage available. The number of corn earworm eggs shriveled or missing, indicative of predation by O. insidiosus, was highest for cages with O. insidiosus adults (65% for either egg density). In cages with fourth-instar O. insidiosus, the percentage of corn earworm egg shriveled or missing was 45% with 2 eggs available and 32% with 4 eggs available. At all densities of eggs, the number of eggs shriveled or missing in cages with second-instar O. insidiosus was not significantly higher than in control cages. The number of first-instar corn earworms shriveled or missing was highest with fourth-instar O. insidiosus (≈ 52% loss at either larval density). Approximately 47% of larvae at both densities were shriveled or missing in cages with adult O. insidiosus. As was the case with eggs, the number of corn earworm larvae shriveled or missing in cages with second-instar O. insidiosus was not significantly different from that for the controls. Predation on second-instar corn earworms by adult O. insidiosus was not significant.

scholarly journals Comparative toxicity between Neem and pepper mint oils nano formulations against Agrotis ipsilon (Hufn.) larvae ( Lepidoptera : Noctuidae)

2019 ◽  
Vol 1 (1) ◽  
Author(s):  
Nadia Zikry Dimetry
Keyword(s):  
Insect Pests ◽  
Larval Instar ◽  
Management Program ◽  
Fourth Instar ◽  
Peppermint Oil ◽  
Insecticidal Effect ◽  
Lc50 Value ◽  
Nano Emulsion ◽  
Lepidoptera Noctuidae ◽  
Lc50 And Lc90

 Applications of nanotechnology in agriculture will result in the development of efficient and potential approaches towards the management of insect pests. The toxicity effects of four essential oils peppermint, thyme, camphor and sage oils were tested against the fourth instar larvae of A. ipsilon to select the most effective essential oil to be converted to the nano form. According to the results obtained, peppermint oil was the most toxic compound. The toxicity of  bulk and nano- formulations of neem  and pepper mint oils were tested  against  2nd and 4th instar  larvae of A. ipsilon . The  activity based on LC50  values revealed that the LC50 of loaded neem or pepper mint were lower (0.62 and 36.47 ppm) compared with neem  or pepper mint oil nano-emulsion and bulk neem  for the second larval instar. The different formulations of neem are more potent than in case of pepper mint oil as LC50 and LC90 values were significantly less. The same trend was found concerning the 4th larval instar . Age of treated larvae had a detrimental effect on the response to the compounds tested. It was noticed that the younger larvae were much more sensitive to the prepared compounds compared to the older ones. The least LC50  value for loaded  neem  nano-emulsion was 6.68 ppm compared with the highest value for  bulk neem oil ( 16.68 ppm ) for the fourth instar larvae.  Also,   LC 90  values followed the same trend as in  case ofLC50.  Again, the toxicity of loaded peppermint oil had the most insecticidal activity as expressed by the lowest LC50  value ( 51.9 ppm) with more insecticidal effect than the bulk( 125.43 ppm)  or nano-emulsion (85.43 ppm). The present results indicated that these novel systems could be used in integrated pest management program for A. ipsilon control

Dispersal of 32P-treated larvae of Spodoptera litura and Spodoptera mauritia (Lepidoptera: Noctuidae)

1975 ◽  
Vol 26 (6) ◽  
pp. 985
Author(s):  
B Persson
Keyword(s):  
Spodoptera Litura ◽  
Geiger Counter ◽  
Fourth Instar ◽  
Dispersal Pattern ◽  
Patchy Distribution ◽  
Lepidoptera Noctuidae ◽  
Experimental Plots ◽  
Made In

32P-tagged fifth-instar larvae of Spodoptera litura (Fab.) and fourth-instar larvae of Spodoptera mauritia (Boisd.) were released in experimental plots, 10 by 10 m, of clover and grass respectively and traced once a day and once a night for 2 weeks by means of a Geiger counter. The clover had a patchy distribution and was mixed with grass. The dispersal pattern was not random. In the plot with S. mauritia more radiation readings were obtained in the upwind sectors. In the plots withS. litura the majority of the contacts were made in the clover, few in the grass. The results indicate that in both species the direction of the wind may have had an influence on dispersal.

Utilisation of entomopathogenic nematodes, Heterorhabditis spp. and Steinernema spp., for the control of Agrotis ipsilon (Lepidoptera, Noctuidae) in China

Nematology ◽  
2014 ◽  
Vol 16 (1) ◽  
pp. 31-40 ◽  
Author(s):  
Xun Yan ◽  
Xiandong Wang ◽  
Richou Han ◽  
Xuehong Qiu
Keyword(s):  
Larval Stage ◽  
Entomopathogenic Nematodes ◽  
Field Trials ◽  
Fourth Instar ◽  
Agrotis Ipsilon ◽  
Exposure Rate ◽  
Black Cutworm ◽  
The Third ◽  
Lepidoptera Noctuidae

Entomopathogenic nematodes (EPN) have good application prospects for the control of the black cutworm, Agrotis ipsilon. In the present study, the effects of isolate, exposure rate, temperature and larval stage on EPN infectivity to A. ipsilon were evaluated. Results of in vitro tests showed that Steinernema carpocapsae Mex and Heterorhabditis indica LN2 were the most virulent and promising species, causing 80.0 and 83.3% mortality, respectively, to the third instar larvae at 25°C and 72 h after infection. Mortality of A. ipsilon caused by the nematodes was significantly affected by EPN exposure rate, temperature and the larval stage. Both S. carpocapsae and H. indica caused greater mortality to the third instar of A. ipsilon at 25°C than at 15, 20 and 30°C. Both EPN isolates also caused higher mortality to the second instar than to the third and fourth instar larvae of A. ipsilon. The field trials of EPN for the control of A. ipsilon also showed that S. carpocapsae Mex and H. indica LN2 reduced the damage caused by A. ipsilon and increased the cabbage yield when compared with the control. Both EPN isolates showed better control effects than cyfluthrin and Bacillus thuringiensis, indicating that these two EPN isolates could be used for sustainable control of A. ipsilon in vegetable fields in China.

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