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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Descrição e mapeamento de caracteres norfo-anatômicos foliares em Pilocarpus Vahl (Rutaceae) e gêneros relacionados / Description and mapping of morpho-anatomical characters from leaves of Pilocarpus Vahl (Rutaceae) and related genera

Muntoreanu, Thais Gomes 24 April 2008 (has links)
A maioria dos estudos filogenéticos envolvendo Rutaceae foi baseada em dados macromoleculares e poucos utilizaram gêneros neotropicais. Uma exceção a esses trabalhos, foi a análise filogenética de Pilocarpus, um gênero de Rutaceae neotropical, baseada em caracteres morfológicos proposta por Dias e colaboradores. Considerando a importância dos estudos anatômicos em análises cladísticas, os quais podem constituir uma importante fonte de informações para a própria definição de estados de caráter e conseqüente proposição de homologia primária dos caracteres, o presente estudo teve como objetivo investigar e mapear caracteres foliares para Pilocarpus e gêneros relacionados com base na anatomia vegetal. Para tanto, analisou-se a organização estrutural foliar de 12 espécies, empregando-se as técnicas usuais em anatomia vegetal à dissociação de epidermes, secções transversais e longitudinais, e diafanização, adotando-se as microscopias de luz e eletrônica de varredura. Foram descritos 32 caracteres morfo-anatômicos foliares, dentre estes podem ser citados: ornamentação da cutícula; tipos de tricomas, estômatos, estruturas secretoras, cristais e células do periciclo; características do mesofilo e da venação. Com o mapeamento destes caracteres, baseado na filogenia proposta por Dias e colaboradores, foi possível observar a tendência de alguns caracteres serem informativos para determinados terminais, ou até mesmo para o grupo Pilocarpus, propondo suas possíveis relações filogenéticas. Diante disso, observou-se a tendência de que grande parte destes caracteres sejam homoplásticos, 8 dos 32 caracteres sejam autapomórficos. Apenas os estados referente a drusas de oxalato de cálcio no parênquima paliçádico e drusas de oxalato de cálcio no pecíolo, possívelmente, representem uma sinapomorfia para Pilocarpus. Além disso, as árvores mapeadas foram agrupadas de acordo com o número de caracteres que alguns terminais apresentaram em comum. Por exemplo, Raulinoa echinata e Helietta apiculata foram os terminais que apresentaram um maior número de caracteres em comum. No entanto, não foi possível afirmar quais são os caracteres filogeneticamente informativos, sendo necessário a inclusão dos dados anatômicos à matriz de caracteres morfológicos proposta por Dias e colaboradores, a fim de que novas informações sejam geradas e/ou comprovadas. / Most of the phylogenetics studies involving Rutaceae were based on macromolecular data and few used neotropicais generas. An exception of these works, was the phylogenetic analysis about Pilocarpus, a genus of neotropical Rutaceae, based on morphological characters proposed for Dias and collaborators. Considering the importance of the anatomical studies in cladistics, which can constitute an important source of informations for itself definition about states of character and consequent proposition of primary homology of the characters, the goals of the present study were to investigate and mapping leaves\' characters for Pilocarpus and related genera based on the vegetative anatomy. For these studies, the structural leaf organization of 12 species were analysed, using the usual techniques in vegetative anatomy to the dissociation of epidermis, cross and longitudinal sections and diafanization, adopting the Optical microscopy and scanning electron microscopy. Thirty two morfo-anatomical leaves characters were described: ornamentation of the cuticle; kind of trichomes, stomata, secretory structures, crystals and cells of the pericycle; characteristics of the mesophyll and venation. With the mapping of these characters, based on the phylogenetic proposed by Dias and collaborators, was possible to observe the tendency of some characters to be informative for determined taxons, or even for the group Pilocarpus, proposing its possible relations Phylogenetic. With this, was observed the tendency of what great part of these characters be homoplastics, 8 of 32 characters are autapomorphic. Druse calcium oxalate in the palisade parenchyma and in the petiole, possibly, represent a synapomorphic traits for Pilocarpus. Beside this, the mapped trees were grouped in accordance with the number of characters that some taxons presented in common. For example, Raulinoa echinata and Helietta apiculata were the species that presented the biggest number of characters in common. However, it was not possible to affirm what the characters are phylogenetic informative, being necessary the inclusion of the anatomical data to the matrix of morphological characters proposed by Dias and collaborators, so that new informations are produced and / or proved.
2

Cayaponia silva manso (cucurbitaceae juss.), no estado de Goiás: uma abordagem morfológica e anatômica / Cayaponia silva manso (cucurbitaceae juss.), in the state of Goiás: a morphological and anatomical approach

Cardoso Junior, Ilvan Martins 31 March 2017 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-02T14:55:48Z No. of bitstreams: 2 Dissertação - Ilvan Martins Cardoso Junior - 2017.pdf: 3056691 bytes, checksum: 9cda811486de905028e888877de67cb8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-02T14:56:07Z (GMT) No. of bitstreams: 2 Dissertação - Ilvan Martins Cardoso Junior - 2017.pdf: 3056691 bytes, checksum: 9cda811486de905028e888877de67cb8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-05-02T14:56:07Z (GMT). No. of bitstreams: 2 Dissertação - Ilvan Martins Cardoso Junior - 2017.pdf: 3056691 bytes, checksum: 9cda811486de905028e888877de67cb8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-31 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Cayaponia Silva Manso (Cucurbitaceae Juss.), In the State of Goiás: a morphological and anatomical approach - Cayaponia Silva Manso comprises about 60 species of which 47 occur in Brazil. Several studies have been carried out with species of this genus in view of the proven pharmacological potential for some taxa, mainly C. tayuya (Vell) Cogn., C. martiana (Cogn.) Cogn. In Goiás it was reported the existence of seven species that constitute two groups that are differentiated respectively by the habits and habitats where they are found, one formed by the species C. espelina (Silva Manso) Cogn., C. rugosa Gomes-Klein et Pirani and C. weddellii (Naudin) Cogn. And the other group comprising the species C. tayuya (Vell.) Cogn., C. citrullifolia (Griseb.) Cogn., C. diversifolia (Cogn.) Cogn. and C. podantha Cogn. Some studies have been carried out to solve complexes in other botanical families. Studies on the anatomy of vegetative and reproductive organs have presented results that contribute to a better circumscription for the species under study. In this work, morphological, taxonomic and anatomical studies were carried out with the objective of adding new information that allows a better delimitation and recognition of the studied species. A preliminary survey of information on Cayaponia species occurred in the State of Goiás. 41 expeditions were carried out in 42 municipalities. Specimens of 7 species were collected in the State of Goiás. For the morphological and taxonomic studies, the collected material was processed, herborized and identified according to the usual methodology. For the anatomical analysis part of the material was preserved fresh in a freezer at 10 ° C, another part fixed in alcohol70, in FAA70 or FPA70. In Chapter 1 the taxonomic treatment for the species occurring in Goiás was carried out. A key of identification, morphological and taxonomic description was presented, as well as illustrations of the species studied. In Chapter 2 the description of foliar architecture of the species under study was presented. Also in this chapter an identification key was developed for the species under study based on foliar architecture and venation patterns. Chapter 3 presents anatomical analyzes of petiole and leaf blade, scanning electron microscopy and histochemical tests that were used in the separation of taxa. Statistical tests, Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were applied with the objective of performing a prospection of morpho-anatomic characters that support the groups delimited in previous chapters. / Cayaponia Silva Manso (Cucurbitaceae Juss.), no Estado de Goiás: uma abordagem morfológica e anatômica - Cayaponia Silva Manso compreende em torno de 60 espécies das quais 47 ocorrem no Brasil. Diversos estudos tem sido realizados com espécies deste gênero tendo em vista o potencial farmacêutico comprovado para alguns taxa, principalmente C. tayuya (Vell) Cogn., C. martiana (Cogn.) Cogn. Em Goiás foi relatado a existência de sete espécies que constituem dois grupos que são diferenciados respectivamente pelos hábitos e habitats onde são encontrados, um formado pelas espécies C. espelina (Silva Manso) Cogn., C. rugosa Gomes-Klein et Pirani e C. weddellii (Naudin) Cogn. e o outro grupo compreendendo as espécies C. tayuya (Vell.) Cogn., C. citrullifolia (Griseb.) Cogn. e C. diversifolia (Cogn.) Cogn. e C. podantha Cogn. Alguns estudos tem sido realizados para solução de complexos em outras famílias botânicas. Trabalhos sobre anatomia de órgãos vegetativos e reprodutivos têm apresentado resultados que contribuem com uma melhor circunscrição para as espécies em estudo. Neste trabalho, foram realizados estudos morfológicos, taxonômicos e anatômicos com o objetivo de acrescentar novas informações que permitam melhor delimitação e reconhecimento das espécies estudadas. Foi realizado o levantamento prévio de informações sobre as espécies Cayaponia, ocorrentes no Estado de Goiás. Procedeu-se 41 expedições a 42 municípios. Foram coletados exemplares de 7 espécies ocorrentes no Estado de Goiás. Para os estudos morfológicos e taxonômicos o material coletado, foi processado, herborizado e identificado segundo metodologia usual. Para as análises anatômicas parte do material foi preservado fresco em freezer a 10°C, outra parte fixado em álcool70, em FAA70 ou FPA70. No Capítulo 1 foi realizado o tratamento taxonômico para as espécies ocorrentes em Goiás. Foi apresentada uma chave de identificação, descrição morfológica e taxonômica, além de ilustrações das espécies estudadas. No Capítulo 2 foi apresentada a descrição de arquitetura foliar das espécies em estudo. Ainda nesse capítulo foi elaborada uma chave de identificação para as espécies em estudo baseada na arquitetura foliar e padrões de venação. O Capítulo 3 apresenta análises anatômicas de pecíolo e lâmina foliar, microscopia eletrônica de varredura e testes histoquímicos que foram empregados na separação dos taxa. Testes estatísticos, análise de Componentes Principais (PCA, em inglês) e Análise Hierárquica de Cluster (HCA), foram aplicados com o objetivo de realizar uma prospecção de caracteres morfoanatômicos que suportam os grupos delimitados nos capítulos anteriores.
3

Descrição e mapeamento de caracteres norfo-anatômicos foliares em Pilocarpus Vahl (Rutaceae) e gêneros relacionados / Description and mapping of morpho-anatomical characters from leaves of Pilocarpus Vahl (Rutaceae) and related genera

Thais Gomes Muntoreanu 24 April 2008 (has links)
A maioria dos estudos filogenéticos envolvendo Rutaceae foi baseada em dados macromoleculares e poucos utilizaram gêneros neotropicais. Uma exceção a esses trabalhos, foi a análise filogenética de Pilocarpus, um gênero de Rutaceae neotropical, baseada em caracteres morfológicos proposta por Dias e colaboradores. Considerando a importância dos estudos anatômicos em análises cladísticas, os quais podem constituir uma importante fonte de informações para a própria definição de estados de caráter e conseqüente proposição de homologia primária dos caracteres, o presente estudo teve como objetivo investigar e mapear caracteres foliares para Pilocarpus e gêneros relacionados com base na anatomia vegetal. Para tanto, analisou-se a organização estrutural foliar de 12 espécies, empregando-se as técnicas usuais em anatomia vegetal à dissociação de epidermes, secções transversais e longitudinais, e diafanização, adotando-se as microscopias de luz e eletrônica de varredura. Foram descritos 32 caracteres morfo-anatômicos foliares, dentre estes podem ser citados: ornamentação da cutícula; tipos de tricomas, estômatos, estruturas secretoras, cristais e células do periciclo; características do mesofilo e da venação. Com o mapeamento destes caracteres, baseado na filogenia proposta por Dias e colaboradores, foi possível observar a tendência de alguns caracteres serem informativos para determinados terminais, ou até mesmo para o grupo Pilocarpus, propondo suas possíveis relações filogenéticas. Diante disso, observou-se a tendência de que grande parte destes caracteres sejam homoplásticos, 8 dos 32 caracteres sejam autapomórficos. Apenas os estados referente a drusas de oxalato de cálcio no parênquima paliçádico e drusas de oxalato de cálcio no pecíolo, possívelmente, representem uma sinapomorfia para Pilocarpus. Além disso, as árvores mapeadas foram agrupadas de acordo com o número de caracteres que alguns terminais apresentaram em comum. Por exemplo, Raulinoa echinata e Helietta apiculata foram os terminais que apresentaram um maior número de caracteres em comum. No entanto, não foi possível afirmar quais são os caracteres filogeneticamente informativos, sendo necessário a inclusão dos dados anatômicos à matriz de caracteres morfológicos proposta por Dias e colaboradores, a fim de que novas informações sejam geradas e/ou comprovadas. / Most of the phylogenetics studies involving Rutaceae were based on macromolecular data and few used neotropicais generas. An exception of these works, was the phylogenetic analysis about Pilocarpus, a genus of neotropical Rutaceae, based on morphological characters proposed for Dias and collaborators. Considering the importance of the anatomical studies in cladistics, which can constitute an important source of informations for itself definition about states of character and consequent proposition of primary homology of the characters, the goals of the present study were to investigate and mapping leaves\' characters for Pilocarpus and related genera based on the vegetative anatomy. For these studies, the structural leaf organization of 12 species were analysed, using the usual techniques in vegetative anatomy to the dissociation of epidermis, cross and longitudinal sections and diafanization, adopting the Optical microscopy and scanning electron microscopy. Thirty two morfo-anatomical leaves characters were described: ornamentation of the cuticle; kind of trichomes, stomata, secretory structures, crystals and cells of the pericycle; characteristics of the mesophyll and venation. With the mapping of these characters, based on the phylogenetic proposed by Dias and collaborators, was possible to observe the tendency of some characters to be informative for determined taxons, or even for the group Pilocarpus, proposing its possible relations Phylogenetic. With this, was observed the tendency of what great part of these characters be homoplastics, 8 of 32 characters are autapomorphic. Druse calcium oxalate in the palisade parenchyma and in the petiole, possibly, represent a synapomorphic traits for Pilocarpus. Beside this, the mapped trees were grouped in accordance with the number of characters that some taxons presented in common. For example, Raulinoa echinata and Helietta apiculata were the species that presented the biggest number of characters in common. However, it was not possible to affirm what the characters are phylogenetic informative, being necessary the inclusion of the anatomical data to the matrix of morphological characters proposed by Dias and collaborators, so that new informations are produced and / or proved.
4

Variabilita křídelní žilnatiny vážek (Insecta: Odonata) - geometricko-morfometrická studie / Variation in dragonfly wing venation with application of geometric morphometrics (Insecta: Odonata)

Přibylová, Petra January 2015 (has links)
The pattern of wing venation in dragonflies (Odonata) bears a set of characters commonly used in systematics. The aim of this thesis is to identify the wing venation variability of dragonflies by various methods of geometric morphometric. The wing venation variability was examined on the level of suborder, family, species and also in respect to dimorphism through the principal component analysis (PCA), redundancy analysis (RDA) and centroid size. Data set consisting of images of 46 dragonfly species, belonging to 43 genera and 24 families was obtained from institutional entomological collections. The research carried out that Zygoptera have a large variety of wing contours. The wing venation variability of Epiprocta is shown primarily in the costa and node area. Between sexes there is no noticeable difference in shape or structure of the wing. The ratio between wing length and width and the pterostigma shape is dependent on dragonfly body size. Key words: Odonatoptera, Odonata, Epiprocta, Zygoptera, wing venation, variability, geometric morphometrics
5

Morfologie a evoluce vybraných skupin Palaeodictyopterida (Insecta: Palaeoptera) / Morphology and evolution of selected groups of Palaeodictyopterida (Insecta: Palaeoptera)

Pecharová, Martina January 2017 (has links)
Palaeodictyopterida is remarkable insect superorder, which formed a significant part of the diversity of upper Palaeozoic insects, but disappeared by the end of the Permian. The main synapomorphy of the superorder is the piercing-sucking mouthparts in the form of a rostrum consisting of five styles. This rostrum was probably used to pierce on plant tissue and for the juice sucking. The same type of mouthparts shared by adults was present also in larvae of Palaeodictyopterida. The external copulatory organs of the superorder members was also showed some morphological interests. The male genitalia consist of a pair of gonostyli and two penial lobes, similarly to the genitalia of recent Ephemeroptera. The female genitalia of Palaeodictyopterida are developed in a form of the ovipositor that can be compared with the endophytic ovipositor of some recent Odonata. This morphological features support placement of Palaeodictyopterida as sister group of Odonatoptera + Panephemeroptera. The main aim of the work was to describe new representatives of the order Megasecoptera, the second largest group of Palaeodictyopterida. Wing venation of Megasecoptera exhibits a reduction of the longitudinal and transverse veins in comparison with the order Palaeodictyoptera. Other body structures were examined mainly in the...
6

Discovering the Complex Aerodynamics of Flapping Flight with Bio-kinematics Using Boltzmann and Eulerian Methods

Feaster, Jeffrey Oden 31 August 2017 (has links)
The cross-sectional geometry of an insect wing has historically been simplified to a rectangular, elliptic, or having a streamlined airfoil shape. Up until this point, no analysis has utilized a morphologically accurate insect wing. As such, there remains significant questions as to whether or not there are aerodynamic benefits to the wing vein structure accompanying the already known structural improvements. The present study uses a bumblebee specimen (Bombus pensylvanicus) acquired by the author, scanned using a skyscan microCT scanner, and post-processed for computational analysis. The resulting geometry captures the naturally occurring vein structures present in the bee wing and is used to better understand aerodynamic effects of biological corrugation. The aerodynamics associated with a morphologically accurate bee wing geometry are explored in two and three dimensions for the first time. Multiple methodologies are validated with experimental results presented in the literature to capture the fluid dynamics in two dimensions including the Lattice-Boltzmann method and unstructured dynamic remeshing using a Navier-Stokes approach. The effects of wing cross-section are compared first with common geometries used in the literature in two dimensions and then between cross-sections extracted at different locations along the wing span. A three-dimensional methodology is validated and used to compare the true bee wing with one using a rectangular cross-section in symmetric hovering. The influence of spanwise cross-section is revisited in three dimensions and compared to the results found in two-dimensions for the same kinematics in forward flight. The final focus of the dissertation is the first simulation of a morphologically accurate wing using kinematics described in the literature. / PHD
7

Morfologie a taxonomie nově objevených zástupců skupiny Megasecoptera ze svrchního karbonu severní Číny (Insecta: Palaeodictyopteroida) / Megasecoptera: morphology and taxonomy of newly discovered specimens from Upper Carboniferous of northern China (Insecta: Palaeodictyopteroida)

Pecharová, Martina January 2013 (has links)
The extinct insect group of Palaeodictyopteroida (Insecta: Palaeoptera) comprised mainly phytophagous species and occurred from Upper Carboniferous to Upper Permian. Megasecoptera is one of several orders of belonging to this group. Although, the order Megasecoptera comprised over 20 described families, morphology of some body structures are insufficiently studied. The present thesis deals with evaluation of new material comprising the extensive set of 76 fossil insect specimens from the Upper Carboniferous (Bashkirian) of northern China. The fossils having excellent state of preservation of the wings and other body structures provide new insights concerning the external morphology of Megasecoptera. All studied specimens were attributed based on wing venation pattern into two known megasecopteran genera within families Brodiopteridae and Sphecopteridae. The aim of the present thesis is examine the morphology and variability of wing venation of two newly proposed species Brodioptera sp. n. and Cyclocelis sp. n. from site in northern China. In addition the following methods of geometric morphometrics based on landmarks were used for comparison of venational characters: a comparison of centroid size, procrustes analysis, principal component analysis and thin plate spline. Variability of wing venation...
8

Models of Vascular Pattern Formation in Leaves.

Feugier, François 14 December 2006 (has links) (PDF)
J'étudie la formation du système vasculaire des feuilles des plantes à l'aide de modèles mathématiques. L'hypothèse de canalisation d'une phytohormone, l'auxin, stipule que l'auto activation de son transport entre les cellules crée des chemins préférentiels qui se différencieront plus tard en système vasculaire. J'entreprends une analyse numérique de modèles de canalisation sur une grande matrice et parviens à créer des motifs branchés dans lesquels circule l'auxin. Une analyse de stabilité d'un modèle simplifié nous éclaire sur les raisons de la formation de ces motifs et l'impossibilité de créer un réseau réticulé. La majorité des plantes ayant un système vasculaire réticulé, je modifie le modèle de façon à obtenir ce type de réseau. En ajoutant une variable biologiquement plausible je parviens à créer un réseau réticulé dans lequel l'auxin circule uniformément. Enfin, je discute des relations entre la formation du système vasculaire et de la spirale de phyllotaxie.
9

Morfologie křídelní nervatury larválních stádií Palaeodictyoptera ze svrchního karbonu Polska / Palaeodictyoptera: morphology of immature wings from the Upper Carboniferous of Poland

Tippeltová, Zuzana January 2013 (has links)
Insect wings are very specific and unique structures in animal kingdom. Wing morphology is a result of long-standing complicated evolutionary process and until recently the way how the wings have evolved is not completely clarified. The flight ability is one of the most important event in insect history because it allows them to exploit new habitats, escape from predators or find the sexual partner. Here we present the newly discovered material consisting of Palaeodictyoptera immature wings from the Upper Carboniferous (Westphalian A) of Poland. This order became extinct in the end of Permian, however during the Late Paleozoic was remarkably diversified. Until recently, number of adult palaeodictyopterans have been described, however the immature stages are relatively unknown due to lack of suitable fossils. Immature wings present in this thesis have undoubtedly palaeodictyopterous affinities with atribution within superfamilies Breyeroidea and Homoiopteroidea. However, their familial assignment into Breyeriidae (morphotype A) and Homiopteridae (morphotype B) based on fore wing venation characters is not definite because of wing venation limits in early ontogenetic stages. The aim of the present work is a complex description of 14 new palaeodictyopteriids immature wings, and to point out certain important...
10

SPATIAL-SPECTRAL ANALYSIS FOR THE IDENTIFICATION OF CROP NITROGEN DEFICIENCY BASED ON HIGH-RESOLUTION HYPERSPECTRAL LEAF IMAGES

Zhihang Song (8764215) 26 April 2024 (has links)
<p dir="ltr">Among the major row crops in the United States, corn and soybeans stand out due to their high nutritional value and economic importance. Achieving optimal yields is restrained by the challenge of fertilizer management. Many fields experience yield losses due to insufficient mineral nutrients like nitrogen (N), while excessive fertilization raises costs and environmental risks. The critical issue is the accurate determination of fertilizer quantity and timing, underscoring the need for precise, early-stage diagnostics. Emerging high-throughput plant phenotyping techniques, notably hyperspectral imaging (HSI), have been increasingly utilized to identify plant’s responses to abiotic or biotic stresses. Varieties of HSI systems have been developed, such as airborne imaging systems and indoor imaging stations. However, most of the current HSI systems’ signal quality is often compromised by various environmental factors. To address the issue, a handheld hyperspectral imager known as LeafSpec was recently developed at Purdue University and represents a breakthrough with its ability to scan corn or soybean leaves at exceptional spatial and spectral resolutions, improving plant phenotyping quality at reduced costs. Most of the current HSI data processing methods focus on spectral features but rarely consider spatially distributed information. Thus, the objective of this work was to develop a methodology utilizing spatial-spectral features for accurate and reliable diagnostics of crop N nutrient stress. The key innovations include the designing of spatial-spectral features based on the leaf venation structures and the feature mining method for predicting the plant nitrogen condition. First, a novel analysis method called the Natural Leaf Coordinate System (NLCS) was developed to reallocate leaf pixels and innovate the nutrient stress analysis using pixels’ relative locations to the venation structure. A new nitrogen prediction index for soybean plants called NLCS-N was developed, outperforming the conventional averaged vegetation index (Avg. NDVI) in distinguishing healthy plants from nitrogen-stressed plants with higher t-test p-values and predicting the plant nitrogen concentration (PNC) with higher R-squared values. In one of the test cases, the p-values and R-squared values were improved, respectively, from 2.1×10<sup>-3</sup> to 6.92×10<sup>-12</sup> and from 0.314 to 0.565 by Avg. NDVI and NLCS-N. Second, a corn leaf venation segmentation algorithm was developed to separate the venation structure from a corn leaf LeafSpec image, which was further used to generate 3930 spatial-spectral (S-S) features. While the S-S features could be the input variable to build a PNC prediction model, a feature selection mechanism was developed to improve the models’ accuracy in terms of reduced cross-validation errors. In one of the test cases, the cross-validation root mean squared errors were reduced compared with the leaf mean spectra from 0.273 to 0.127 using the selected features. Third, several novel spatial-spectral indexes for corn leaves were developed based on the color distributions at the venation level. The top-performing indexes were selected through a ranking system based on Cohen’s d values and the R-squared values, resulting in a best-performing S-S N prediction index with 0.861 R-squared values for predicting the corn PNC in a field assay. The discussion sections provided insights into how a robust PNC prediction index could be developed and related to plant science. The methodologies outlined offer a framework for broader applications in spatial-spectral analysis using leaf-level hyperspectral imagery, serving as a guide for scientists and researchers in customizing their future studies within this field.</p>

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