EFFECTS OF THE LARVAL PARASITES DIADEGMA INSULARIS AND MICROPLITIS PLUTELLAE ON THE ABUNDANCE OF THE DIAMONDBACK MOTH IN SASKATCHEWAN RAPE AND MUSTARD CROPS

1973 ◽  
Vol 53 (4) ◽  
pp. 911-914 ◽  
Author(s):  
L. G. PUTNAM
Keyword(s):  
Plutella Xylostella ◽  
Diamondback Moth ◽  
Larval Population ◽  
Moth Population ◽  
The Third ◽  
Brassica Spp ◽  
Host Generation ◽  
Larval Parasites

The larvae of the diamondback moth (Plutella xylostella) in the rape and mustard (Brassica spp.) crops of Saskatchewan are parasitized in varying degrees by the ichneumonid Diadegma insularis and the braconid Microplitis plutellae. During a 10-yr period, reduction of the first host generation by the two parasites together varied from 35 to 81%, averaging 68%. M. plutellae was usually predominant in this generation. In a given larval population, the lesser percentage would permit a following moth population about three times that of the greater. The overall average parasitism declined to 41% in the second host generation, where it is of less importance because of the reduced importance of the third host generation.

scholarly journals Production of Natural Insecticide on Management of Plutella xylostella (Linnaeus, 1758) (Lepidoptera: Plutellidae) in Family Farming

2021 ◽  
Vol 13 (7) ◽  
pp. 47
Author(s):  
Cristiane G. L. Ruiz ◽  
Marilza S. Costa ◽  
Santino Seabra Jr ◽  
Mônica J. B. Pereira
Keyword(s):  
Plutella Xylostella ◽  
Diamondback Moth ◽  
Farming Systems ◽  
Oviposition Deterrent ◽  
Family Farming ◽  
Collard Greens ◽  
The Third ◽  
First Instar ◽  
Natural Insecticide ◽  
Deterrent Activity

Collard greens are commonly grown in family farming systems; however, damage caused by the diamondback moth Plutella xylostella (Lepidoptera: Plutellidae) reduces yields, leading to successive applications of insecticides and consequently, environmental and toxicological problems. Therefore, it is essential to search for alternatives that reduce the use of pesticides and are economically viable and accessible to small farmers. This study was aimed at evaluating the insecticidal activity of aqueous extracts of neem and tobacco on P. xylostella. First instar caterpillars were offered collard leaf discs treated with different concentrations (30 caterpillars per treatment) and after the third day, mortality was evaluated. To evaluate ovicidal properties, collard leaves with 30 eggs were immersed in extracts and after 48 h, viability was measured. Oviposition deterrent activity was assessed with 23 couples of P. xylostella released in cages (repetitions) containing treated collard plants and after 48 h, the number of eggs per plant was recorded. Neem and tobacco extracts exhibited larvicidal, ovicidal, and oviposition deterrent properties against P. xylostella, indicating that the use of these extracts may be promising alternatives in family farming systems.

scholarly journals Toxicity and residual control of Plutella xylostella L. (Lepidoptera: Plutellidae) with Bacillus thuringiensis Berliner and insecticides

2012 ◽  
Vol 42 (8) ◽  
pp. 1335-1340 ◽  
Author(s):  
Carla Pedroso de Moraes ◽  
Luis Amilton Foerster
Keyword(s):  
Bacillus Thuringiensis ◽  
Plutella Xylostella ◽  
Diamondback Moth ◽  
Growth Inhibitor ◽  
Weather Conditions ◽  
Larval Population ◽  
Resistant Population ◽  
Cruciferous Plants ◽  
Residual Control ◽  
Third Instar Larvae

Plutella xylostella L. is the most important worldwide pest of cruciferous plants and indiscriminate use of insecticides has led to the resistance of the species to different groups. This research was conducted to compare the toxicity and persistence of two strains of Bacillus thuringiensis to P. xylostella larvae. Concentrations between 125 and 500g 100L-1 of water of the commercial products were evaluated and compared to the insect growth inhibitor diflubenzuron and to the neurotoxic pyrethroid deltamethrin. The efficacy of the insecticides was compared between treated plants kept indoor greenhouse and outdoor. Third instar larvae were more susceptible to B. thuringiensis than first instar ones. Agree and Dipel showed similar control rates of third instars until 10 days after treatment, but on the 15th day, Agree was significantly more efficient than Dipel. Both B. thuringiensis formulations showed a reduction in mortality after 10 days when the treated plants were exposed to natural weather conditions in comparison to the same treatments kept inside greenhouse. Dimilin (100g 100L-1 of water) and deltamethrin (30ml of commercial product 100L-1 of water) were not efficient to control third instar larvae of P. xylostella. This inefficiency cannot be attributed to a resistant population of P. xylostella since the larval population used in the experiments was not subjected to insecticide pressure, once the crop was organically cultivated all year round. The results showed that both formulations of B. thuringiensis are sound alternatives for the control of the diamondback moth in organically conducted cruciferous crops, considering the high residual control provided under subtropical weather conditions.

Evaluation of adjuvants for foliar application of Steinernema carpocapsae against larvae of the diamondback moth (Plutella xylostella)

Nematology ◽  
2005 ◽  
Vol 7 (1) ◽  
pp. 37-44 ◽  
Author(s):  
Sibylle Schroer ◽  
Xiaoli Yi ◽  
Ralf-Udo Ehlers
Keyword(s):  
Plutella Xylostella ◽  
Foliar Application ◽  
Entomopathogenic Nematode ◽  
Larval Instar ◽  
Diamondback Moth ◽  
Fold Increase ◽  
Steinernema Carpocapsae ◽  
Control Measures ◽  
The Third ◽  
Insect Mortality

Abstract Increasing resistance to chemical insecticides in field populations of the diamondback moth (Plutella xylostella) has stimulated research on alternative control measures. The entomopathogenic nematode Steinernema carpocapsae may be one such alternative, particularly against the third larval instar of P. xylostella. The LC50 for the second instar is 38, the third 13 and the fourth 22 nematodes/larva. Plutella xylostella pupae were not affected by the nematodes, although mortality in leaf disk bioassays after application of nematodes in water seldom surpassed 50%. Therefore, additives were tested to improve nematode performance. Only Triton X-100 (0.3%) caused phytotoxic effects. The addition of xanthan gum or potassium alginate resulted in a two-fold increase of insect mortality at 80% relative humidity (RH) and a five-fold increase at 60% RH. Mixtures of 0.3% xanthan or alginate with 0.3% surfactants further improved efficacy. In water the LT50 for S. carpocapsae against P. xylostella larvae was > 40 h. Using a mixture of 0.3% xanthan or 0.3% alginate with 0.3% surfactant, the LT50 was reduced to < 25 h.

scholarly journals Efficacy of anthranilic insecticide E2Y45 20 SC (Chlorantraniliprole) against Plutella xylostella L. in cabbage, Brassica oleracea var. capitata

2016 ◽  
Vol 8 (3) ◽  
pp. 1584-1588
Author(s):  
Sudhendu Sharma ◽  
Ravinder Singh ◽  
C. K. Gill
Keyword(s):  
Brassica Oleracea ◽  
Plutella Xylostella ◽  
Mode Of Action ◽  
Untreated Control ◽  
Diamondback Moth ◽  
Marketable Yield ◽  
Larval Population

Experiments were conducted at farmer’s cabbage fields to evaluate the bioefficacy of anthranilic insecticide i.e. E2Y45 20 SC (Chlorantraniliprole) having novel mode of action against the diamondback moth Plutella xylostella L. E2Y45 20 SC was applied @ 25.0, 37.5 and 50.0 ml/ha and was compared with Padan 50 SP (cartap hydrochloride) @ 500 g/ha and the untreated control. Lowest mean larval population after two sprays was recorded in higher dose of E2Y 45 20 SC i.e. @ 50.0 ml/ha (0.08 larvae/plant) at 7 days after treatment followed by medium and lower dose of E2Y 45 20 SC i.e. @ 37.5ml/ha (0.10 larvae/plant) and 25.0 ml/ha (0.33 larvae/plant). The larval population in these treatments was significantly lower than standard check, Padan 50 SP (2.56 larvae/plant), and untreated control (9.73 larvae/plant). The highest marketable yield (262.89 q/ha) was recorded in E2Y 45 20 SC @ 50.0 ml/ha which was significantly higher than Padan 50 SP (239.65 q/ha). Lowest yields were recorded in untreated control (106.00 q/ha). Conclusively, medium (37.5 ml/ha) and higher (50.0 ml/ha) dose of E2Y 45 20 SC (chlorantraniliprole) significantly reduced the larval population of P. xylostella and increased the cabbage yield.

Effects of rhizobacteria on the biology and behavior of Plutella xylostella (Lepidoptera: Plutellidae)

2017 ◽  
Vol 43 (2) ◽  
pp. 195
Author(s):  
Robson Thomaz Thuler ◽  
Fernando Henrique Iost Filho ◽  
Hamilton César De Oliveira Charlo ◽  
Sergio Antônio De Bortoli
Keyword(s):  
Plutella Xylostella ◽  
Diamondback Moth ◽  
Insect Behavior ◽  
Control Treatment ◽  
Pupal Weight ◽  
Larval Feeding ◽  
Direct Effects ◽  
Plant Feeding ◽  
Kluyvera Ascorbata ◽  
And Behavior

Plant induced resistance is a tool for integrated pest management, aimed at increasing plant defense against stress, which is compatible with other techniques. Rhizobacteria act in the plant through metabolic changes and may have direct effects on plant-feeding insects. The objective of this study was to determine the effects of cabbage plants inoculated with rhizobacteria on the biology and behavior of diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae). Cabbage seeds inoculated with 12 rhizobacteria strains were sowed in polystyrene trays and later transplanted into the greenhouse. The cabbage plants with sufficient size to support stress were then infested with diamondback moth caterpillars. Later, healthy leaves suffering injuries were collected and taken to the laboratory to feed P. xylostella second instar caterpillars that were evaluated for larval and pupal viability and duration, pupal weight, and sex ratio. The reduction of leaf area was then calculated as a measure of the amount of larval feeding. Non-preference for feeding and oviposition assays were also performed, by comparing the control treatment and plants inoculated with different rhizobacterial strains. Plants inoculated with the strains EN4 of Kluyvera ascorbata and HPF14 of Bacillus thuringiensis negatively affected the biological characteristics of P. xylostella when such traits were evaluated together, without directly affecting the insect behavior.

Mutation of P‐element somatic inhibitor induces male sterility in the diamondback moth, Plutella xylostella

2021 ◽  
Author(s):  
Yaohui Wang ◽  
Xia Xu ◽  
Xi’en Chen ◽  
Xiaowei Li ◽  
Honglun Bi ◽  
...  
Keyword(s):  
Male Sterility ◽  
Plutella Xylostella ◽  
Diamondback Moth ◽  
P Element

scholarly journals On the virulence of the entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae (Ascomycota: Hypocreales), against the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae)

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Muhammad Shehzad ◽  
Muhammad Tariq ◽  
Tariq Mukhtar ◽  
Asim Gulzar
Keyword(s):  
Sex Ratio ◽  
Beauveria Bassiana ◽  
Entomopathogenic Fungi ◽  
Plutella Xylostella ◽  
Metarhizium Anisopliae ◽  
Insect Pest ◽  
Diamondback Moth ◽  
Economic Damage ◽  
Offspring Sex Ratio ◽  
Development Of Resistance

Abstract Background The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a noxious pest of cruciferous crops all over the world causing serious economic damage. Management of insect pest generally depends on chemical control; however, due to development of resistance against all types of insecticides, alternative approaches especially utilization of a microbial agent is inevitable. Results Potential of 2 entomopathogenic fungi (EPF), viz., Beauveria bassiana and Metarhizium anisopliae, was evaluated against 2nd and 3rd larval instars of P. xylostella by adopting leaf dip and direct spraying methods under laboratory conditions. Significant mortality rate was achieved by each fungus under adopted methodologies. However, B. bassiana was found to be more effective in both conditions than M. anisopliae. Highest mean corrected mortality (77.80%) was recorded, when spores of B. bassiana were sprayed on the 2nd instar larvae (LC50=1.78×104/ml) after the 6th day of treatment. Similarly, incase of M. anisopliae LC50 for the 2nd instar at the same methodology was 2.78×104/ml with a mortality percentage of 70.0%. Offspring sex ratio was non-significantly related to treatment concentration and methodology, except for the control. Conclusion Beauveria bassiana and M. anisopliae had potential to suppress P. xylostella infestations when applied appropriately. Present findings suggested that B. bassiana and M. anisopliae when sprayed on immatures of host insect had more effect as compared to leaf dip procedure. Furthermore, no significant effect of concentrations was observed on sex ratio.

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