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Joydip Dhar - One of the best experts on this subject based on the ideXlab platform.
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Bifurcation in Plant-Pest-Natural Enemy Interaction Dynamics with Gestation Delay for Both Pest and Natural Enemy
International Journal of Bifurcation and Chaos, 2019Co-Authors: Vijay Kumar, Joydip Dhar, Harbax S. BhattiAbstract:During this analysis, as per natural control approach in Pest management, a Plant-Pest dynamics with biological control is proposed, here assuming that the Pest and natural enemy are having differe...
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Bifurcation dynamics of a Plant-Pest-natural enemy system in polluted environment incorporating gestation delays
Ricerche di Matematica, 2019Co-Authors: Vijay Kumar, Joydip Dhar, Harbax S. BhattiAbstract:In this study, a three species Plant-Pest-natural enemy compartmental model incorporating gestation delays for both Pests and natural enemies in a polluted environment is proposed. The boundedness and positivity properties of the model are established. Equilibria and their stability analysis are carried out for all possible steady states. The existence of Hopf bifurcation in the system is analyzed. It is established that the natural enemy free steady state $$E_2$$ is stable for specific threshold parameter values $$\tau _1\in (0,\tau _{10}^+)$$, i.e., gestation delay for Pest species belongs to zero and it’s own critical value, $$\tau _{10}^+$$ and the coexisting steady state $$E^*$$ is stable for specific threshold parameter values $$\tau _1\in (0,\tau _{10}^+)$$ and $$\tau _2\in (0,\tau _{20}^+)$$, i.e., gestation delay for Pest species belongs to zero and it’s own critical value, $$\tau _{10}^+$$ and gestation delay for natural enemies belongs to zero and it’s own critical value, $$\tau _{20}^+$$. If both gestation delays for Pest and natural enemies, i.e., $$\tau _1, \tau _2$$ respectively cross their threshold parameter values, i.e., $$\tau _1>\tau _{10}^{+},\tau _2>\tau _{20}^{+}$$, then the system perceived oscillating behavior and Hopf bifurcation occurs in the system. The sensitivity analysis of the system at interior steady state is presented and the sensitive indices of the variables are identified. Finally, simulations are performed to support our analytic results with a distinct set of parametric values.
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Bifurcation dynamics of a Plant-Pest-natural enemy system in polluted environment incorporating gestation delays
Ricerche di Matematica, 2019Co-Authors: Vijay Kumar, Joydip Dhar, Harbax S. BhattiAbstract:In this study, a three species Plant-Pest-natural enemy compartmental model incorporating gestation delays for both Pests and natural enemies in a polluted environment is proposed. The boundedness and positivity properties of the model are established. Equilibria and their stability analysis are carried out for all possible steady states. The existence of Hopf bifurcation in the system is analyzed. It is established that the natural enemy free steady state $$E_2$$ E 2 is stable for specific threshold parameter values $$\tau _1\in (0,\tau _{10}^+)$$ τ 1 ∈ ( 0 , τ 10 + ) , i.e., gestation delay for Pest species belongs to zero and it’s own critical value, $$\tau _{10}^+$$ τ 10 + and the coexisting steady state $$E^*$$ E ∗ is stable for specific threshold parameter values $$\tau _1\in (0,\tau _{10}^+)$$ τ 1 ∈ ( 0 , τ 10 + ) and $$\tau _2\in (0,\tau _{20}^+)$$ τ 2 ∈ ( 0 , τ 20 + ) , i.e., gestation delay for Pest species belongs to zero and it’s own critical value, $$\tau _{10}^+$$ τ 10 + and gestation delay for natural enemies belongs to zero and it’s own critical value, $$\tau _{20}^+$$ τ 20 + . If both gestation delays for Pest and natural enemies, i.e., $$\tau _1, \tau _2$$ τ 1 , τ 2 respectively cross their threshold parameter values, i.e., $$\tau _1>\tau _{10}^{+},\tau _2>\tau _{20}^{+}$$ τ 1 > τ 10 + , τ 2 > τ 20 + , then the system perceived oscillating behavior and Hopf bifurcation occurs in the system. The sensitivity analysis of the system at interior steady state is presented and the sensitive indices of the variables are identified. Finally, simulations are performed to support our analytic results with a distinct set of parametric values.
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Stage-structured Plant-Pest-natural enemy interaction dynamics incorporating gestation delay for both Pest and natural enemy
Modeling Earth Systems and Environment, 2019Co-Authors: Vijay Kumar, Joydip Dhar, Harbax S. BhattiAbstract:The biological control is an alternate of chemical control as well as other Pest control methods. In the present study, we propose a stage-structured food chain dynamics of Plant-Pest-natural enemies with gestation delays for both Pests and natural enemies. The positivity and boundedness properties of the system are proved. The existence criteria of the equilibria and corresponding stability conditions are established. The existence of Hopf bifurcation in the system is analyzed. When there are delays in the system, it is established that the steady states $$E_2$$ E 2 and $$E^*$$ E ∗ are stable for specific threshold values, $$\tau _1\in [0,\tau _{10}^+)$$ τ 1 ∈ [ 0 , τ 10 + ) , $$\tau _2\in [0,\tau _{20}^+)$$ τ 2 ∈ [ 0 , τ 20 + ) . When $$\tau _1>\tau _{10}^+$$ τ 1 > τ 10 + , $$\tau _2>\tau _{20}^+$$ τ 2 > τ 20 + system is unstable and oscillatory character of the system is observed. Further, the natural enemy free steady state, $$E_2$$ E 2 and the coexisting steady state, $$E^*$$ E ∗ are stable for specific threshold values $$\tau _1\tau _{20}^{+}$$ τ 1 < τ 10 + , τ 2 > τ 20 + and $$\tau _1\tau _{20}^{++}$$ τ 1 < τ 10 + + , τ 2 > τ 20 + + respectively. If both $$\tau _1, \ \tau _2$$ τ 1 , τ 2 crosses the threshold values, i.e., $$\tau _1>\tau _{10}^{+}, \ \tau _2>\tau _{20}^{+}$$ τ 1 > τ 10 + , τ 2 > τ 20 + and $$\tau _1>\tau _{10}^{++}, \ \tau _2>\tau _{20}^{++}$$ τ 1 > τ 10 + + , τ 2 > τ 20 + + , system perceived oscillating behavior and Hopf bifurcation occurs. Calculated the respective sensitive indices of the system parameters at the coexisting steady state by performing the sensitivity analysis. Further numerical experimentations have been carried out to support our analytic findings.
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Stage-structured Plant-Pest-natural enemy interaction dynamics incorporating gestation delay for both Pest and natural enemy
Modeling Earth Systems and Environment, 2018Co-Authors: Vijay Kumar, Joydip Dhar, Harbax S. BhattiAbstract:The biological control is an alternate of chemical control as well as other Pest control methods. In the present study, we propose a stage-structured food chain dynamics of Plant-Pest-natural enemies with gestation delays for both Pests and natural enemies. The positivity and boundedness properties of the system are proved. The existence criteria of the equilibria and corresponding stability conditions are established. The existence of Hopf bifurcation in the system is analyzed. When there are delays in the system, it is established that the steady states $$E_2$$ and $$E^*$$ are stable for specific threshold values, $$\tau _1\in [0,\tau _{10}^+)$$ , $$\tau _2\in [0,\tau _{20}^+)$$ . When $$\tau _1>\tau _{10}^+$$ , $$\tau _2>\tau _{20}^+$$ system is unstable and oscillatory character of the system is observed. Further, the natural enemy free steady state, $$E_2$$ and the coexisting steady state, $$E^*$$ are stable for specific threshold values $$\tau _1 \tau _{20}^{+}$$ and $$\tau _1 \tau _{20}^{++}$$ respectively. If both $$\tau _1, \ \tau _2$$ crosses the threshold values, i.e., $$\tau _1>\tau _{10}^{+}, \ \tau _2>\tau _{20}^{+}$$ and $$\tau _1>\tau _{10}^{++}, \ \tau _2>\tau _{20}^{++}$$ , system perceived oscillating behavior and Hopf bifurcation occurs. Calculated the respective sensitive indices of the system parameters at the coexisting steady state by performing the sensitivity analysis. Further numerical experimentations have been carried out to support our analytic findings.
N. J. Spence - One of the best experts on this subject based on the ideXlab platform.
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The challenge of providing Plant Pest diagnostic services for Africa
European Journal of Plant Pathology, 2008Co-Authors: Julian J. Smith, Jeff K. Waage, James W. Woodhall, Sam J. Bishop, N. J. SpenceAbstract:The consequences of a globalisation of trade and climate change present an increased threat from first-entry Pests and a challenge to Plant health authorities. In this paper, Pest reporting for the continents of Africa and Europe are discussed, and argued as a barometer of effective Plant Pest Diagnostic Services (PPDS) in terms of human capacity, infrastructure and policy-culture for phytosanitary issues. To illustrate particular areas of concern, case studies are presented on recent Pest events which include outbreaks of Ralstonia solanacearum on Pelargonium, Xanthomonas camPestris pv. musacearum on banana (banana Xanthomonas wilt) and Puccinia graminis f.sp. tritici race Ug99 on wheat (black stem rust). Examples are given of some recent initiatives to invigorate diagnostic capacity in East Africa, spanning state-of-the-art centres of excellence, traditional capacity building and networking projects, and grass-root level 'going-public' Pest surveillance initiatives. Discussion is presented on the provision of PPDS and the impact of technology, institutional factors, the private sector, accreditation of services and policy. Emphasis is placed on the role of PPDS in support of regulatory policy. In recognising the precarious nature of many African cropping systems, the argument is made for a more consolidated approach to PPDS in and for Africa. The paper is presented from the perspective of European practitioners in Pest diagnostic and risk analysis.
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Patterns of Plant Pest introductions in Europe and Africa
Agricultural Systems, 2008Co-Authors: Jeff K. Waage, Julian J. Smith, James W. Woodhall, Sam J. Bishop, David R. Jones, N. J. SpenceAbstract:An analysis is made of the pattern of reported introductions of Plant Pests (insects, mites, fungi, bacteria and viruses) over the 20th century into Africa and Europe. Rates of reported introductions followed very different patterns between the continents, with European introductions rising over the century, while reported African introductions peaked mid-century and declined thereafter. This pattern is consistent with two quite different, but not mutually exclusive, hypotheses based on (1) continental differences in rates of arrival and establishment of new species and (2) differences in changing capacity to detect and identify new introductions. Patterns of Pest taxa introduced, and crops affected, were broadly similar between continents.
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Integrating drivers influencing the detection of Plant Pests carried in the international cut flower trade
Journal of environmental management, 2007Co-Authors: Francisco J. Areal, Andrew Macleod, Julia Touza, Katharina Dehnen-schmutz, Charles Perrings, Maria Giovanna Palmieri, N. J. SpenceAbstract:This paper analyses the cut flower market as an example of an invasion pathway along which species of non-indigenous Plant Pests can travel to reach new areas. The paper examines the probability of Pest detection by assessing information on Pest detection and detection effort associated with the import of cut flowers. We test the link between the probability of Plant Pest arrivals, as a precursor to potential invasion, and volume of traded flowers using count data regression models. The analysis is applied to the UK import of specific genera of cut flowers from Kenya between 1996 and 2004. There is a link between Pest detection and the Genus of cut flower imported. Hence, Pest detection efforts should focus on identifying and targeting those imported Plants with a high risk of carrying Pest species. For most of the Plants studied, efforts allocated to inspection have a significant influence on the probability of Pest detection. However, by better targeting inspection efforts, it is shown that Plant inspection effort could be reduced without increasing the risk of Pest entry. Similarly, for most of the Plants analysed, an increase in volume traded will not necessarily lead to an increase in the number of Pests entering the UK. For some species, such as Carthamus and Veronica, the volume of flowers traded has a significant and positive impact on the likelihood of Pest detection. We conclude that analysis at the rank of Plant Genus is important both to understand the effectiveness of Plant Pest detection efforts and consequently to manage the risk of introduction of non-indigenous species.
Anita Neal - One of the best experts on this subject based on the ideXlab platform.
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Sri Lankan weevil Myllocerus undecimpustulatus undatus Marshall
EDIS, 2020Co-Authors: Anita NealAbstract:Myllocerus undecimpustulatus undatus Marshall, the Sri Lankan weevil, is a Plant Pest with a wide range of hosts. This weevil spread from Sri Lanka into India and then Pakistan where many subspecies of Myllocerus undecimpustulatus Faust are considered Pests of more than 20 crops. In the United States, the Sri Lankan weevil was first identified on Citrus sp. in Pompano Beach a city in Broward County Florida. Three specimens were identified by Dr. Charles W. O’Brien, first as Myllocerus undecimpustulatus, a species native to southern India, and then again as Myllocerus undatus Marshall native to Sri Lanka, finally as Myllocerus undecimpustulatus undatus Marshall to show its status as a subspecies. This 4-page fact sheet was written by Anita Neal, and published by the UF Department of Entomology and Nematology, November 2013. http://edis.ifas.ufl.edu/in1016
Kunwer Singh Jatav - One of the best experts on this subject based on the ideXlab platform.
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hybrid approach for Pest control with impulsive releasing of natural enemies and chemical Pesticides a Plant Pest natural enemy model
Nonlinear Analysis: Hybrid Systems, 2014Co-Authors: Kunwer Singh Jatav, Joydip DharAbstract:Abstract The agricultural Pests can be controlled effectively by simultaneous use (i.e., hybrid approach) of biological and chemical control methods. Also, many insect natural enemies have two major life stages, immature and mature. According to this biological background, in this paper, we propose a three tropic level Plant–Pest–natural enemy food chain model with stage structure in natural enemy. Moreover, impulsive releasing of natural enemies and harvesting of Pests are also considered. We obtain that the system has two types of periodic solutions: Plant–Pest-extinction and Pest-extinction using stroboscopic maps. The local stability for both periodic solutions is studied using the Floquet theory of the impulsive equation and small amplitude perturbation techniques. The sufficient conditions for the global attractivity of a Pest-extinction periodic solution are determined by the comparison technique of impulsive differential equations. We analyze that the global attractivity of a Pest-extinction periodic solution and permanence of the system are evidenced by a threshold limit of an impulsive period depending on pulse releasing and harvesting amounts. Finally, numerical simulations are given in support of validation of the theoretical findings.
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Hybrid approach for Pest control with impulsive releasing of natural enemies and chemical Pesticides: A Plant–Pest–natural enemy model
Nonlinear Analysis: Hybrid Systems, 2014Co-Authors: Kunwer Singh Jatav, Joydip DharAbstract:Abstract The agricultural Pests can be controlled effectively by simultaneous use (i.e., hybrid approach) of biological and chemical control methods. Also, many insect natural enemies have two major life stages, immature and mature. According to this biological background, in this paper, we propose a three tropic level Plant–Pest–natural enemy food chain model with stage structure in natural enemy. Moreover, impulsive releasing of natural enemies and harvesting of Pests are also considered. We obtain that the system has two types of periodic solutions: Plant–Pest-extinction and Pest-extinction using stroboscopic maps. The local stability for both periodic solutions is studied using the Floquet theory of the impulsive equation and small amplitude perturbation techniques. The sufficient conditions for the global attractivity of a Pest-extinction periodic solution are determined by the comparison technique of impulsive differential equations. We analyze that the global attractivity of a Pest-extinction periodic solution and permanence of the system are evidenced by a threshold limit of an impulsive period depending on pulse releasing and harvesting amounts. Finally, numerical simulations are given in support of validation of the theoretical findings.
Rodrigo Diaz - One of the best experts on this subject based on the ideXlab platform.
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Cold Tolerance and Distribution of Myllocerus undecimpustulatus undatus (Coleoptera: Curculionidae) (Sri Lankan Weevil) in Florida
2019Co-Authors: Anita S. Neal, Ronald D. Cave, Rodrigo DiazAbstract:Myllocerus undecimpustulatus undatus Marshall, the Sri Lankan weevil, is a serious Plant Pest with a wide range of hosts. It was first identified in the United States on Citrus sp. in Davie, Broward County, Florida, on 15 September 2000. This weevil has over 150 different host Plant species including fruits, nuts, vegetables, and ornamentals. It has been detected in 26 counties in Florida through December 2012. Historical data from 2000–15 obtained from the Division of Plant Industry’s field agent submissions indicate the northward spread of the Sri Lankan weevil in North America. Cold tolerance data indicate adults are acclimated to lower temperatures until reaching 0 °C and–5 °C. A sustained and multiple exposure experiment that more closely resembles actual cold events in Florida and other potential areas tested insects gathered in summer and winter to determine increased cold hardiness. This may provide valuable information to assist Extension agents and Pest management professionals in preparing control strategies.
