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Population Dynamics of Cabbage Butterfly (Pieris brassicae) and Cabbage Aphids (Brevicoryne brassicae) on Five Cultivars of Cauliflower at Peshawar  [PDF]
Mohammad Younas,Mohammad Naeem,Abdur Raqib,Shah Masud
Asian Journal of Plant Sciences , 2004,
Abstract: The studies on population dynamics of Cabbage butterfly and Cabbage aphids on different Cultivars of cauliflower namely Snowball, Snowdrift, Tropical, Pioneer and Meigettsal were carried out at the Research Farm of Entomology Section, Agricultural Research Institute Tarnab Peshawar. Cabbage butterfly (Pieris brassicae) and aphids (Bravicoryne brassicae) were recorded as the major insect pests of Cauliflower crop at ARI, Tarnab, Peshawar. None of the 5 Cultivars was found completely resistant to the infestation of Cabbage butterfly and aphids. The highest average of 86.67 larvae/plant was recorded in the first week of November and the lowest average of 0.67 larvae/plant was recorded in the first week of December. The lowest and the highest average mean population of larvae were observed on Cultivars Meigettsal and snow ball, respectively. During study population density of aphids on cauliflower Cultivars ranged from 0.00 to 31.76 aphids/cm2 leaf area. The lowest and highest average mean population of aphids recorded on Cultivars Snow Drift and Meigettsal, respectively. Cultivar snow drift was found the least preferred to aphids throughout the season. During study cultivar Meigettsal proved to be best against Cabbage butterfly, but showed poor performance against aphids. Cultivar snowdrift showed good performance against aphids and cabbage butterfly
Performance Evaluation of Camb Biopesticides to Control Cabbage Butterfly (Pieris brassicae) in Cauliflower Crop
Ahmad Usman Zafar,Idrees Ahmad Nasir,Ahmed Ali Shahid,Muhammad Sarwar Rahi
Pakistan Journal of Biological Sciences , 2002,
Abstract: CAMB Bt. based and fungus based biopesticides, commercial Bt. formulation from mycogen and a new chemical pesticide Methoxyfenozide (RH2485-240SC) were tested on cauliflower field against cabbage butterfly (Pieris brassicae). All pesticides successfully controlled the population of cabbage butterfly in cauliflower crop. The efficacy against I to V instar larvae and field stability of CAMB Bt. biopesticide was better than chemical and other biopesticides. So, CAMB Bt. can be safely recommended for pest management strategies against Lepidopteral pests on vegetables with no harmful effects on its predators as in case with chemical pesticides.
Developmental Response of Cabbage Butterfly, Pieris brassicae L. (Lepidoptera: Pieridae) on Different Cole Crops Under Laboratory and Field Condition  [PDF]
Arshad Ali,Parvez Qamar Rizvi
Asian Journal of Plant Sciences , 2007,
Abstract: An attempt was made to find out the developmental response of cabbage butterfly, Pieris brassicae on different cole crops under Laboratory and field condition. The overall development of P. brassicae was recorded significantly higher on yellow sarson (40.70±2.38 and 37.87±1.93 days) as compared to lower on cabbage (34.15±1.80 and 33.12±1.95 days), under laboratory and field condition, respectively (p≤0.05). All the developmental stages (egg, larval instars, prepupal and pupal) of P. brassicae was registered their maximum development period on yellow sarson followed by gobhi sarson, cauliflower and cabbage under both conditions. However, the maximum development period of adult was recorded on cabbage and minimum on yellow sarson in both situations. The cabbage butterfly tuned their highest generation mortality on yellow sarson (0.3565 and 0.3645) in contrast to lowest on cabbage (0.2555 and 0.2486) in both laboratory and field conditions, respectively. The number of adults was recorded maximum in laboratory than the field condition on all the cole crops. It is possible due to the presence of natural enemies (predators and parasitoids), abiotic factors (temperature, relative humidity and rainfall) and some unknown factors in the field condition.
Preliminary investigation on the effects of biological and synthetic insecticides on large white butterfly (Pieris brassicae L.) larvae  [PDF]
Kloko?ar-?mit Zlata D.,In?i? Du?anka V.,Vukovi? Slavica M.,Filipovi? Maja M.
Zbornik Matice Srpske za Prirodne Nauke , 2007, DOI: 10.2298/zmspn0712075k
Abstract: Control of cabbage pests is oriented towards the use of efficient but high-risk insecticides, some of them being endocrine disruptors. Biopesticides are more environment-friendly, operator-and consumers-safe, but they have low initial toxicity, low efficacy to advanced larval stages, and they require certain knowledge of pest and host biology. In our laboratory experiments we have investigated the effects of formulated synthetic pyrethroid cypermethrin (0.3 l/ha) and biological products - formulations based on Bacillus thuringiensis subsp. kurstaki (2 and 3/ha) and Spinosad (0.1 l/ha) - on large white butterfly (Pieris brassicae L.) larvae-instars 2, 3, 4 and 5. The effect of insecticides was inversely proportional to larval instars. Btk effect could be improved if tank-mixed with cypermethrin. The mixing of ready-made products allows a reduction 3 and 6 times compared with the recommended dose, still obtaining satisfactory results. Rate of leaf damage was reduced when tank mixtures were used. Use of two products in mixture would be of significance especially for control of advanced late instars late in season, when Btk action alone is insufficient. Spinosad was effective in inducing mortality and reducing leaf damage by all larval instars, therefore we assume that the dose could be reduced. Feeding rate and mortality are equally important parameters when assessing biopesticide efficacy. This strategy should also reduce the possibility of inducing resistance in pest population. It also tends to reduce the residues in commodities and is good solution in production of hygienic and health safe food.
Egg Laying of Cabbage White Butterfly (Pieris brassicae) on Arabidopsis thaliana Affects Subsequent Performance of the Larvae  [PDF]
Sven Geiselhardt, Kinuyo Yoneya, Beatrice Blenn, Navina Drechsler, Jonathan Gershenzon, Reinhard Kunze, Monika Hilker
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0059661
Abstract: Plant resistance to the feeding by herbivorous insects has recently been found to be positively or negatively influenced by prior egg deposition. Here we show how crucial it is to conduct experiments on plant responses to herbivory under conditions that simulate natural insect behaviour. We used a well-studied plant – herbivore system, Arabidopsis thaliana and the cabbage white butterfly Pieris brassicae, testing the effects of naturally laid eggs (rather than egg extracts) and allowing larvae to feed gregariously as they do naturally (rather than placing single larvae on plants). Under natural conditions, newly hatched larvae start feeding on their egg shells before they consume leaf tissue, but access to egg shells had no effect on subsequent larval performance in our experiments. However, young larvae feeding gregariously on leaves previously laden with eggs caused less feeding damage, gained less weight during the first 2 days, and suffered twice as high a mortality until pupation compared to larvae feeding on plants that had never had eggs. The concentration of the major anti-herbivore defences of A. thaliana, the glucosinolates, was not significantly increased by oviposition, but the amount of the most abundant member of this class, 4-methylsulfinylbutyl glucosinolate was 1.8-fold lower in larval-damaged leaves with prior egg deposition compared to damaged leaves that had never had eggs. There were also few significant changes in the transcript levels of glucosinolate metabolic genes, except that egg deposition suppressed the feeding-induced up-regulation of FMOGS-OX2, a gene encoding a flavin monooxygenase involved in the last step of 4-methylsulfinylbutyl glucosinolate biosynthesis. Hence, our study demonstrates that oviposition does increase A. thaliana resistance to feeding by subsequently hatching larvae, but this cannot be attributed simply to changes in glucosinolate content.
EFFECT OF EXTRACTS FROM GERANIACEAE PLANTS ON PIERIS BRASSICAE L.  [PDF]
MARIA WAWRZYNIAK
Journal of Central European Agriculture , 2010,
Abstract: The conducted studies comprised the analyses of activity of extracts derived from selected plants of the Geranium family on some processes of large white butterfly (Pieris brassicae) development (oviposition, survival of eggs and caterpillar feeding). The results proved that all tested extracts showed activity against large white butterfly. Geranium pratense L. and Geranium senquineum L. showed better activity than other Geranium plants. Water extracts from these species protected cabbage plants against laying eggs, while applied on eggs caused their mortality. Alcohol and water extracts from G. pratense L. and water extracts from G. senquineum L. increased an amount of food put on mass gain of caterpillars.
Morphological Clines and Weak Drift along an Urbanization Gradient in the Butterfly, Pieris rapae  [PDF]
Sean D. Schoville, Ivo Widmer, Magali Deschamps-Cottin, Stéphanie Manel
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0083095
Abstract: Urban areas are increasing globally, providing opportunities for biodiversity researchers to study the process in which species become established in novel, highly disturbed habitats. This ecological process can be understood through analyses of morphological and genetic variation, which can shed light on patterns of neutral and adaptive evolution. Previous studies have shown that urban populations often diverge genetically from non-urban source populations. This could occur due to neutral genetic drift, but an alternative is that selection could lead to allele frequency changes in urban populations. The development of genome scan methods provides an opportunity to investigate these outcomes from samples of genetic variation taken along an urbanization gradient. Here we examine morphological variation in wing size and diversity at neutral amplified fragment length polymorphisms in the butterfly Pieris rapae L. (Lepidoptera, Pieridae) sampled from the center to the periphery of Marseille. We utilize established and novel environmental correlation approaches to scan genetic variation for evidence of selection. We find significant morphological differences in urban populations, as well as weak genetic structure and decreased genetic diversity in urban versus non-urban sites. However, environmental correlation tests provide little support for selection in our dataset. Our comparison of different methods and allele frequency clines suggests that loci identified as significant are false positives. Although there is some indication that selection may be acting on wing size in urban butterflies, genetic analyses suggest P. rapae are undergoing neutral drift.
Biology of Pieris brassicae (Linnaeus) (Lepidoptera: Pieridae)
under Laboratory Conditions
 [PDF]

Muhammad Aslam,Nazia Suleman
Pakistan Journal of Biological Sciences , 1999,
Abstract: In two experiments conducted in the Department of Entomology, University of Arid Agriculture, Rawalpindi, the duration of larval, pupal and adult stages of Pieris brassicae (Linnaeus) was concluded as 10.25, 7.50 and 5.75 days respectively. The larval, pupal and adult survival was recorded as 83, 62 and 42 per cent. The sex ratio was computed as 2.23: 1.00. The average number of eggs laid per female was 141.25. The larvae preferred radish leaves, while medium number of larvae was attracted to cabbage and the lowest to sarson and turnip.
Modelling butterfly wing eyespot patterns  [PDF]
Rui Dilao,Joaquim Sainhas
Quantitative Biology , 2005, DOI: 10.1098/rspb.2004.2761
Abstract: Eyespots are concentric motifs with contrasting colours on butterfly wings. Eyespots have intra- and inter-specific visual signalling functions with adaptive and selective roles. We propose a reaction-diffusion model that accounts for eyespot development. The model considers two diffusive morphogens and three non-diffusive pigment precursors. The first morphogen is produced in the focus and determines the differentiation of the first eyespot ring. A second morphogen is then produced, modifying the chromatic properties of the wing background pigment precursor, inducing the differentiation of a second ring. The model simulates the general structural organisation of eyespots, their phenotypic plasticity and seasonal variability, and predicts effects from microsurgical manipulations on pupal wings as reported in the literature.
Differential Involvement of Hedgehog Signaling in Butterfly Wing and Eyespot Development  [PDF]
Xiaoling Tong, Anna Lindemann, Antónia Monteiro
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0051087
Abstract: Butterfly eyespots may have evolved from the recruitment of pre-existent gene circuits or regulatory networks into novel locations on the wing. Gene expression data suggests one such circuit, the Hedgehog (Hh) signaling pathway and its target gene engrailed (en), was recruited from a role in patterning the anterior-posterior insect wing axis to a role patterning butterfly eyespots. However, while Junonia coenia expresses hh and en both in the posterior compartment of the wing and in eyespot centers, Bicyclus anynana lacks hh eyespot-specific expression. This suggests that Hh signaling may not be functioning in eyespot development in either species or that it functions in J. coenia but not in B. anynana. In order to test these hypotheses, we performed functional tests of Hh signaling in these species. We investigated the effects of Hh protein sequestration during the larval stage on en expression levels, and on wing size and eyespot size in adults. Hh sequestration led to significantly reduced en expression and to significantly smaller wings and eyespots in both species. But while eyespot size in B. anynana was reduced proportionately to wing size, in J. coenia, eyespots were reduced disproportionately, indicating an independent role of Hh signaling in eyespot development in J. coenia. We conclude that while Hh signaling retains a conserved role in promoting wing growth across nymphalid butterflies, it plays an additional role in eyespot development in some, but not all, lineages of nymphalid butterflies. We discuss our findings in the context of alternative evolutionary scenarios that led to the differential expression of hh and other Hh pathway signaling members across nymphalid species.
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