80 research outputs found

    Brassica-Aphid Interaction: Modulated Challenges and Sustainable Approach for Management

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    Insect pests act as main barrier in enhancing yield potential of Brassica crops. Lipaphis erysimi is considered as one of the most destructive insect species in mustard production due to its voracious type feeding and multiplication. Therefore application of insecticide is inevitable for cultivation of cruciferous crops, although systemic insecticides has been found to be suitable for management of aphid, despite of high cost, residual effect and ecological ramification have necessitated the application of bio and botanical insecticides as novel approach and are recorded significant in research. Aphids having exclusively viviparous parthenogenesis type reproduction from January to March month with the completion of eight generations are helpful in quick mass multiplication. Natural enemies Coccinella spp., Syrphid larvae and bio-pesticide found effective in suppress aphid numbers. Manipulation in sowing dates of mustard crop provides good yield and less incidence of aphid which is proved through research. Lack of environmental resistant varieties has dispensed toward non feasibility of conventional breeding approaches for developing aphid-resistant Brassica. Although application of genetic engineering plan has resulted in moderate success in development of aphid resistance, so far commercialization of such genetically modified crops has not conceivable, intimate the necessity of further insights in to host plant and aphid communication to form effective approach against aphid resistance. Therefore in this chapter the components involved in Brassica aphid communication are highlighted and present statuses and problem in aphid management are discussed

    Analysing count data of Butterflies communities in Jasin, Melaka: a poisson regression analysis

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    Counting outcomes normally have remaining values highly skewed toward the right as they are often characterized by large values of zeros. The data of butterfly communities, had been taken from Jasin, Melaka and consists of 131 number of subject visits in Jasin, Melaka. In this paper, considering the count data of butterfly communities, an analysis is considered Poisson regression analysis as it is assumed to be an alternative way on better suited to the counting process. This research paper is about analysing count data from zero observation ecological inference of butterfly communities in Jasin, Melaka by using Poisson regression analysis. The software for Poisson regression is readily available and it is becoming more widely used in many field of research and the data was analysed by using SAS software. The purpose of analysis comprised the framework of identifying the concerns. Besides, by using Poisson regression analysis, the study determines the fitness of data for accessing the reliability on using the count data. The finding indicates that the highest and lowest number of subject comes from the third family (Nymphalidae) family and fifth (Hesperidae) family and the Poisson distribution seems to fit the zero values

    Radial asymptotics of Lemaitre-Tolman-Bondi dust models

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    We examine the radial asymptotic behavior of spherically symmetric Lemaitre-Tolman-Bondi dust models by looking at their covariant scalars along radial rays, which are spacelike geodesics parametrized by proper length \ell, orthogonal to the 4-velocity and to the orbits of SO(3). By introducing quasi-local scalars defined as integral functions along the rays, we obtain a complete and covariant representation of the models, leading to an initial value parametrization in which all scalars can be given by scaling laws depending on two metric scale factors and two basic initial value functions. Considering regular "open" LTB models whose space slices allow for a diverging \ell, we provide the conditions on the radial coordinate so that its asymptotic limit corresponds to the limit as \ell\to\infty. The "asymptotic state" is then defined as this limit, together with asymptotic series expansion around it, evaluated for all metric functions, covariant scalars (local and quasi-local) and their fluctuations. By looking at different sets of initial conditions, we examine and classify the asymptotic states of parabolic, hyperbolic and open elliptic models admitting a symmetry center. We show that in the radial direction the models can be asymptotic to any one of the following spacetimes: FLRW dust cosmologies with zero or negative spatial curvature, sections of Minkowski flat space (including Milne's space), sections of the Schwarzschild--Kruskal manifold or self--similar dust solutions.Comment: 44 pages (including a long appendix), 3 figures, IOP LaTeX style. Typos corrected and an important reference added. Accepted for publication in General Relativity and Gravitatio

    Observations of the Sun at Vacuum-Ultraviolet Wavelengths from Space. Part II: Results and Interpretations

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    Review on the Impact of Insecticides Utilization in Crop Ecosystem: Their Prosperity and Threats

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    Pesticide covers a wide range of compounds including insecticides, fungicides, herbicides, rodenticides, molluscicides, nematicides, plant growth regulators, and others. Among them, organochlorine insecticides, used successfully in controlling a number of diseases, such as malaria and typhus, were banned or restricted after the 1960s in most of the technologically advanced countries. The introduction of other synthetic insecticides—organophosphate insecticides in the 1960s, carbamates in the 1970s, and pyrethroids in the 1980s, and the introduction of herbicides and fungicides in the 1970s–1980s contributed greatly to pest control and agricultural output. Ideally, a pesticide must be lethal to the targeted pests, but not to nontarget species, including man. Unfortunately, this is not the case, so the controversy of the use and abuse of pesticides has surfaced. The rampant use of these chemicals, under the adage, “if little is good, a lot more will be better” has played with humans and other life forms. The known ecological impacts of insecticides on terrestrial and aquatic ecosystems are reviewed in this chapter. Awareness of the impacts that insecticides are having in our world may help to introduce the management practices that aim at reducing and mitigating those impacts

    Nanobiotechnology: Synthesis components and a few approaches for controlling plant diseases

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    Nanobiotechnology is a rapidly growing field that combines principles of nanotechnology with life sciences, to develop innovative solutions for widespread biomedical, environmental, and agricultural challenges. This review article aims to outline the advanced status of nanoscale approaches in plant pathology, focusing on some of the key achievements and challenges in the field and the application of nanobiotechnology. It covers a range of topics, including nanomaterials in different biological formulations for plant disease management. The article also discusses how nanobiomaterials are being utilized to combat plant diseases and provides insights into the potential future advancements within the field. Overall, this review aims to provide a comprehensive and current perspective on the dynamic and rapid integration of nanotechnology into the realm of plant disease management
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