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Stephen J. Simpson - One of the best experts on this subject based on the ideXlab platform.
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Nutritional ecology and foraging theory
Current opinion in insect science, 2018Co-Authors: David Raubenheimer, Stephen J. SimpsonAbstract:Historically, two fields of research have developed theory around foraging and feeding that have influenced biology more broadly, optimal foraging theory and Nutritional ecology. While these fields have developed largely in parallel, they are complementary with each offering particular strengths. Here we show how an approach developed in the study of Insect Nutrition, called Nutritional geometry, has provided a framework for incorporating key aspects of optimal foraging theory into Nutritional ecology. This synthesis provides a basis for integrating with foraging and feeding the many facets of biology that are linked to Nutrition and is now influencing diverse areas of the biological and biomedical sciences.
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Regulation of salt intake by nymphs of Locusta migratoria
Journal of Insect Physiology, 1993Co-Authors: S. Trumper, Stephen J. SimpsonAbstract:Abstract Fifth-instar nymphs of Locusta migratoria exhibited regulatory feeding for salt by defending an “intake target” for salt vs non-mineral nutrients when challenged with a range of choices of artificial foods varying in salt content. When provided with no choice of food, however, nymphs did not regulate salt intake, due to the greater strength of regulatory mechanisms for protein and carbohydrate. Instead, they tolerated a 12-fold variation in salt intake and kept intake of non-mineral nutrients constant. Performance was reduced when dietary salt levels were less than 0.64% dry weight of Wesson's mixture. The intake target level was 1.8% in a food containing 20% protein and 10% digestible carbohydrate. This falls within the range of concentration of salts found in plant tissues. Possible regulatory mechanisms are discussed and results are interpreted within the new geometric framework for Insect Nutrition.
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The geometry of feeding: a new way of looking at Insect Nutrition
Proceedings of the 8th International Symposium on Insect-Plant Relationships, 1992Co-Authors: Stephen J. Simpson, David Raubenheimer, P. G. ChambersAbstract:Meeting the Nutritional needs of an Insect can be seen as a problem of multidimensional geometry. At any given time there is a requirement by the tissues for a particular quantity and mix of nutrients. This constitutes a “Nutritional target” in an n-dimensional s’ a’ e, where n is the number of nutrients. Providing the tissues with nutrients involves two stages: feeding and post-ingestive processing. Just as there is a Nutritional target, there is also an “intake target”, which is the optimal amount and balance of nutrients that need to be ingested so that post-ingestive processes can operate at maximal efficiency. An Insect eating a Nutritionally homogeneous food is confined to a “rail” in multi-dimensional space. The intake target is only achievable if it lies on the rail. A choice of foods containing different proportions of nutrients expands the Nutritional space available to the Insect from a line (rail) to a volume. Even then, it may be that the intake target is still unreachable.
Venkatakrishnan Sivaraj Saravanan - One of the best experts on this subject based on the ideXlab platform.
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cultivable bacteria associated with larval gut of prothiofos resistant prothiofos susceptible and field caught populations of diamondback moth plutella xylostella and their potential for antagonism towards entomopathogenic fungi and host Insect nutri
Journal of Applied Microbiology, 2007Co-Authors: Pandiyan Indiragandhi, R Anandham, Munusamy Madhaiyan, Selvaraj Poonguzhali, Gilhan Kim, Venkatakrishnan Sivaraj SaravananAbstract:Aims: To evaluate whether the gut bacteria of Insecticide-resistant, Insecticide-susceptible and field-caught populations of the lepidopteran Insect pest diamondback moth (DBM) –Plutella xylostella (L.) – are variable and their role in host protection and Nutrition. Methods and Results: The gut bacterial populations of the three DBM larvae populations were found to be significantly different, irrespective of the developmental stage. The 16S rRNA gene sequence analysis of the DBM gut bacteria revealed that the bacterial population from the prothiofos-resistant larval gut was more diversified with Pseudomonas sp., Stenotrophomonas sp., Acinetobacter sp., and Serratia marcescens. Meanwhile, the susceptible larvae were associated with Brachybacterium sp., Acinetobacter sp. and S. marcescens and the field-caught population harboured a rather simple gut microflora of phylotypes belonging to Serratia. The siderophore-producing Pseudomonas sp. strain PRGB06 showed antagonistic activity towards entomopathogenic fungi, including Beaveria bassiana, Hirsutella thompsonii, Metarhizium anisopliae, Paecilomyces sp., and Paecilomyces tenuipes, while the chitinase-producing S. marcescens enhanced the larval growth and development. Conclusion: There was a significant variation in the gut bacteria from the three different populations of DBM. The production of antifungal siderophore compounds, like pyoverdine, may contribute to host antagonism against entomopathogens. The production of chitinase by gut bacteria appeared to contribute to host Nutrition. Significance and Impact of the Study: The results provide the first comprehensive description of the gut microbial communities in three different populations of an important crucifer pest DBM and suggest that the bacteria associated with the Insect pest could be of interest for developing a pest management strategy.
Warren G. Abrahamson - One of the best experts on this subject based on the ideXlab platform.
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Nutrition as a facilitator of host-race formation: the shift of a stem-boring beetle to a gall host.
Ecological Entomology, 2010Co-Authors: Catherine P. Blair, Rita V. Schlanger, Sarah E. Diamond, Warren G. AbrahamsonAbstract:1. The importance of host-race formation to herbivorous Insect diversity depends on the likelihood that successful populations can be established on a new plant host. A previously unexplored ecological aid to success on a novel host is better Nutritional quality. The role of Nutrition was examined in the shift of the stem-boring beetle Mordellistena convicta to fly-induced galls on goldenrod and the establishment there of a genetically distinct gall host race. 2. First, larvae of the host race inhabiting stems of Solidago gigantea were transplanted into stems and galls of greenhouse-grown S. gigantea plants. At the end of larval development, the mean mass of larvae transplanted to galls was significantly greater than the mass of larvae transplanted to stems, indicating a likely Nutritional benefit during the shift. This advantage was slightly but significantly diminished when the gall-inducing fly feeding at the centre of the gall died early in the season. Additionally, there was a suggestion of a trade-off in the increased mortality of smaller beetle larvae transplanted into galls. 3. In a companion experiment, S. gigantea gall-race beetle larvae were likewise transplanted to S. gigantea stems and galls. Besides the expected greater mass in galls, the larvae also exhibited adaptations to the gall Nutritional environment: larger inherent size, altered tunnelling behaviour, and no diminution of mass pursuant to gall-inducer mortality. 4. In a third line of inquiry, chemical analyses of field-collected S. gigantea plants revealed higher levels of mineral elements important to Insect Nutrition in galls as compared with stems.
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Nutrition as a facilitator of host-race formation: The role of food quality in the shift of a stem-boring beetle to a gall host
Ecological Entomology, 2010Co-Authors: Catherine P. Blair, Rita V. Schlanger, Sarah E. Diamond, Warren G. AbrahamsonAbstract:1. The importance of host-race formation to herbivorous Insect diversity depends on the likelihood that successful populations can be established on a new plant host. A previously unexplored ecological aid to success on a novel host is better Nutritional quality. The role of Nutrition was examined in the shift of the stem-boring beetle Mordellistena convicta to fly-induced galls on goldenrod and the establishment there of a genetically distinct gall host race. 2. First, larvae of the host race inhabiting stems of Solidago gigantea were transplanted into stems and galls of greenhouse-grown S. gigantea plants. At the end of larval development, the mean mass of larvae transplanted to galls was significantly greater than the mass of larvae transplanted to stems, indicating a likely Nutritional benefit during the shift. This advantage was slightly but significantly diminished when the gall-inducing fly feeding at the centre of the gall died early in the season. Additionally, there was a suggestion of a trade-off in the increased mortality of smaller beetle larvae transplanted into galls. 3. In a companion experiment, S. gigantea gall-race beetle larvae were likewise transplanted to S. gigantea stems and galls. Besides the expected greater mass in galls, the larvae also exhibited adaptations to the gall Nutritional environment: larger inherent size, altered tunnelling behaviour, and no diminution of mass pursuant to gall-inducer mortality. 4. In a third line of inquiry, chemical analyses of field-collected S. gigantea plants revealed higher levels of mineral elements important to Insect Nutrition in galls as compared with stems.
Pandiyan Indiragandhi - One of the best experts on this subject based on the ideXlab platform.
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cultivable bacteria associated with larval gut of prothiofos resistant prothiofos susceptible and field caught populations of diamondback moth plutella xylostella and their potential for antagonism towards entomopathogenic fungi and host Insect nutri
Journal of Applied Microbiology, 2007Co-Authors: Pandiyan Indiragandhi, R Anandham, Munusamy Madhaiyan, Selvaraj Poonguzhali, Gilhan Kim, Venkatakrishnan Sivaraj SaravananAbstract:Aims: To evaluate whether the gut bacteria of Insecticide-resistant, Insecticide-susceptible and field-caught populations of the lepidopteran Insect pest diamondback moth (DBM) –Plutella xylostella (L.) – are variable and their role in host protection and Nutrition. Methods and Results: The gut bacterial populations of the three DBM larvae populations were found to be significantly different, irrespective of the developmental stage. The 16S rRNA gene sequence analysis of the DBM gut bacteria revealed that the bacterial population from the prothiofos-resistant larval gut was more diversified with Pseudomonas sp., Stenotrophomonas sp., Acinetobacter sp., and Serratia marcescens. Meanwhile, the susceptible larvae were associated with Brachybacterium sp., Acinetobacter sp. and S. marcescens and the field-caught population harboured a rather simple gut microflora of phylotypes belonging to Serratia. The siderophore-producing Pseudomonas sp. strain PRGB06 showed antagonistic activity towards entomopathogenic fungi, including Beaveria bassiana, Hirsutella thompsonii, Metarhizium anisopliae, Paecilomyces sp., and Paecilomyces tenuipes, while the chitinase-producing S. marcescens enhanced the larval growth and development. Conclusion: There was a significant variation in the gut bacteria from the three different populations of DBM. The production of antifungal siderophore compounds, like pyoverdine, may contribute to host antagonism against entomopathogens. The production of chitinase by gut bacteria appeared to contribute to host Nutrition. Significance and Impact of the Study: The results provide the first comprehensive description of the gut microbial communities in three different populations of an important crucifer pest DBM and suggest that the bacteria associated with the Insect pest could be of interest for developing a pest management strategy.
R Anandham - One of the best experts on this subject based on the ideXlab platform.
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cultivable bacteria associated with larval gut of prothiofos resistant prothiofos susceptible and field caught populations of diamondback moth plutella xylostella and their potential for antagonism towards entomopathogenic fungi and host Insect nutri
Journal of Applied Microbiology, 2007Co-Authors: Pandiyan Indiragandhi, R Anandham, Munusamy Madhaiyan, Selvaraj Poonguzhali, Gilhan Kim, Venkatakrishnan Sivaraj SaravananAbstract:Aims: To evaluate whether the gut bacteria of Insecticide-resistant, Insecticide-susceptible and field-caught populations of the lepidopteran Insect pest diamondback moth (DBM) –Plutella xylostella (L.) – are variable and their role in host protection and Nutrition. Methods and Results: The gut bacterial populations of the three DBM larvae populations were found to be significantly different, irrespective of the developmental stage. The 16S rRNA gene sequence analysis of the DBM gut bacteria revealed that the bacterial population from the prothiofos-resistant larval gut was more diversified with Pseudomonas sp., Stenotrophomonas sp., Acinetobacter sp., and Serratia marcescens. Meanwhile, the susceptible larvae were associated with Brachybacterium sp., Acinetobacter sp. and S. marcescens and the field-caught population harboured a rather simple gut microflora of phylotypes belonging to Serratia. The siderophore-producing Pseudomonas sp. strain PRGB06 showed antagonistic activity towards entomopathogenic fungi, including Beaveria bassiana, Hirsutella thompsonii, Metarhizium anisopliae, Paecilomyces sp., and Paecilomyces tenuipes, while the chitinase-producing S. marcescens enhanced the larval growth and development. Conclusion: There was a significant variation in the gut bacteria from the three different populations of DBM. The production of antifungal siderophore compounds, like pyoverdine, may contribute to host antagonism against entomopathogens. The production of chitinase by gut bacteria appeared to contribute to host Nutrition. Significance and Impact of the Study: The results provide the first comprehensive description of the gut microbial communities in three different populations of an important crucifer pest DBM and suggest that the bacteria associated with the Insect pest could be of interest for developing a pest management strategy.