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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.
11

Evaluation of Postemergence Herbicides for Melon Weed Control

Umeda, Kai 10 1900 (has links)
Bentazon (Basagran®) at 0.5 to 2.0 lb a. i. /A, halosulfuron (Permit®) at 0.025 to 0.10 lb a.i A, and pyridate (Lentagran®) at 0.25 to 1.5 lb a.i. /A were applied postemergence on cantaloupe and watermelon. Bentazon was marginally safe on cantaloupes and controlled purslane and pigweeds. Morningglory and Wright's groundcherry were not effectively controlled by bentazon. Bentazon appeared to be less injurious to watermelons relative to cantaloupes. Halosulfuron was safe on both cantaloupes and watermelons (<15% injury). Halosulfuron at greater than 0.05 lb /A was effective in controlling only Hyssop spurge and London rocket. In one test, halosulfuron gave acceptable control (85 %) of morningglory. Purslane and groundcherry were not controlled by halosulfuron. Pyridate was not safe on cantaloupes causing severe crop stand reduction. Pyridate was safer on watermelons and caused marginally acceptable injury, however, weed control was not effective against groundcherry, spurge or London rocket. Pyridate appeared to give acceptable control of morningglory in one test.
12

Evaluation of Insect Growth Regulators for Management of Whiteflies in Melons

Palumbo, John C. 02 1900 (has links)
Whitefly populations were assessed under different IGR exposure levels, and compared to Admire. When used alone during the season Applaud, Knack, and Sterling significantly reduced immature colonization similar to the standard Admire application and significantly greater than the untreated melons. Applaud treatments, regardless of spray frequency, showed the most consistent reduction in immature whiteflies. Applaud through its vapor activity also appeared to provide a long residual period of control against nymphs. Single applications of Knack and Sterling were considerably less effective in preventing colonization than applying these material twice during the season. These compounds appeared to have considerably less residual activity, which is consistent with their modes of activity. All of the IGRs had a significant impact on the distribution of nymphs among the leaves on the primary vine. In addition, Applaud provided the best melon quality. We now have a good understanding of how the IGRs influence whitefly population growth, the residual mortality of the IGRs and proper application timing for whitefly management. This information will allow us to develop a simple and reliable method that growers and PCAs can use to assess product performance and time spray applications.
13

Toxicological and biological activity of kumchura (Kaempferia galanga L.) to the melon fly Bactrocera cucurbitae Coquillett

Martono, Edhi January 1991 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1991. / Includes bibliographical references (leaves 100-107) / Microfiche. / xiii, 107 leaves, bound ill. 29 cm
14

Honeydew Measles: A Potential Threat to Commercial Honeydew Production

Brown, Paul, Gibson, Richard, Oebker, Norman 05 1900 (has links)
Measles of honeydew melons is not a common problem, but melon growers should be aware that it can cause severe economic damage, under the right environmental conditions. At least one Pinal County grower suffered significant loss during an outbreak of this disease in September 1987.
15

Caractérisation de gènes de la famille des alcool déshydrogénases et alcool acyl transferases chez le melon cantaloup charentais eapproches par transgénèse et protéomique /

Manríquez, Daniel Latché, Alain. Pech, Jean-Claude. January 2006 (has links)
Reproduction de : Thèse de doctorat : Qualité et sécurité des aliments : Toulouse, INPT : 2006. / Titre provenant de l'écran-titre. Bibliogr. 235 réf.
16

Genetic Engineering of Beta-Carotene Production in Honeydew Melons (Cucumis melo L. inodorus)

Ren, Yan 2011 December 1900 (has links)
Genetic transformation is a useful tool to incorporate novel genes, potentially allowing sexual incompatibility and interspecific barriers to be circumvented. The purpose of this study was to improve beta-carotene levels in melon fruits by transferring a phytoene synthase (PSY) gene. At present, there are not sufficient regeneration and transformation studies reported on two commercially important melon types - western shipper cantaloupe and honeydew. To establish a high efficiency shoot regeneration system, we evaluated three types of explants in our elite breeding lines. A shoot tip with a hypocotyl and cotyledon fragments, regenerated shoots whereas a shoot tip with a hypocotyl without cotyledon, did not produce regenerants. Murashige & Skoog (MS) basal medium with 1 mg 1⁻¹ benzyladenine (BA), 0.26 mg 1⁻¹ abscisic acid (ABA) and 0.8 mg 1⁻¹ indole-3-acetic acid (IAA) was the best for regeneration from cotyledon explants in cantaloupe 'F39'. MS basal medium with 1 mg 1⁻¹ BA and 0.26 mg 1⁻¹ ABA was chosen for honeydew '150' to solve a curving-up problem of explants. Fifty to sixty percent of regenerants were found to be polyploids. To establish a reliable Agrobacterium-mediated transformation protocol, kanamycin sensitivity as well as Timentin[trademark] and Clavamox® were evaluated. Kanamycin 200 and 150 mg 1⁻¹ were chosen as the threshold levels for 'F39' and '150' respectively. No significant differences were found between Timentin[trademark] and Clavamox® in 'F39'; however, Clavamox® reduced the incidence of vitrification and increased the frequency of shoot elongation in '150'. A. tumefaciens strain EHA105, harboring pCNL56 carrying nptII and gusA genes, was used to establish a transformation protocol. The transformation efficiency was 0.3% from 'F39' and 0.5% from '150'. We introduced a watermelon PSY-C gene under the control of a fruit-specific promoter of a polygalacturonase gene into '150'. All the transgenic plants were tetraploids based on flow cytometry assays. Up to 32-fold of beta-carotene was elevated in the rind tissue of transgenic honeydew including phytoene increase. This is a very promising result for a further investigation to increase beta-carotene level in flesh tissue using the PSY-C gene with an appropriate promoter.
17

Les Glycoprotéines des surfaces cellulaires végétales : étude particulière d'une glycoprotéine à hydroxyproline dans les plantes de Melon au cours d'une maladie parasitaire.

Esquerré-Tugayé, Marie-Thérèse, January 1900 (has links)
Th.--Sci. biol.--Toulouse 3, 1977. N°: 764.
18

Fisiologia de plantas de meloeiro cultivadas sob diferentes níveis de irrigação / Phisiology of plants the melon cultivaded under different levels of irrigation

Silveira, Enio Marques de Castro January 2013 (has links)
SILVEIRA, Enio Marques de Castro. Fisiologia de plantas de meloeiro cultivadas sob diferentes níveis de irrigação. 2013. 56 f. Dissertação (Mestrado em engenharia agrícola)- Universidade Federal do Ceará, Fortaleza-CE, 2013. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-06-17T19:48:10Z No. of bitstreams: 1 2013_dis_emcsilveira.pdf: 622829 bytes, checksum: b4531a2152319722c83fb11370726eec (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-07-05T17:25:40Z (GMT) No. of bitstreams: 1 2013_dis_emcsilveira.pdf: 622829 bytes, checksum: b4531a2152319722c83fb11370726eec (MD5) / Made available in DSpace on 2016-07-05T17:25:40Z (GMT). No. of bitstreams: 1 2013_dis_emcsilveira.pdf: 622829 bytes, checksum: b4531a2152319722c83fb11370726eec (MD5) Previous issue date: 2013 / The melon is the most exports of fresh fruit produced in Brazil, especially being produced in the states of Rio Grande do Norte and Ceará. All this curcubitaceae commercial orchard in the two regions is performed under irrigated conditions. Thus, measures of efficient use of water become essential for this crop. The improvement in efficiency of water use will depend primarily on a management plan that deliver only the amount of water necessary for their full development. The study aimed to evaluate plant growth, water status, gas exchange and yield of yellow melon grown under different irrigation levels. Therefore, two experiments were conducted in the experimental field of Curu, Paraipaba, CE, using hybrid Gold Mine, with spacing of 2.0 m x 0.4 m, under drip irrigation. The first experiment consisted of weekly evaluation of plant growth in response to applying three different irrigation water levels: 100% 80% and 120% (T1, T2 and T3 respectively) of calculated levels. In the second experiment, in addition to the treatments mentioned above, was inserted another factor: the irrigation schedule of 24 to 48 hours, with four replicates. In this it, was evaluated gas exchange, water potential, the carbohydrate in different parts of the plant, yield and fruit quality. In all treatments the plants showed the lowest water potential daily between 12:00 to 2:00pm. Although stomatal conductance decreases during the day curse, it remained in amounts sufficient for photosynthetic rate nearly constant, with a slight reduction after noon and marked decrease only after 4:00pm. In turn, with the exception of transpiration, which was higher in plants irrigated every 48 hours, the irrigation water levels and the irrigation schedule did not affect gas exchange of plants. Likewise, the production, the size and quality of melon fruits were practically not influenced by treatments. Thus, under the experimental conditions used, the increase or decrease of 20% of irrigation water level calculated and recommended to the melon in the region, did not affect plant development, nor the production. Only the amount of total soluble solids was positively influenced by the addition of 20% of the water levels calculated, when applied daily. / O melão representa a maior parte das exportações de frutas frescas produzidas no Brasil, sendo cultivado em larga escala nos estados do Rio Grande do Norte e Ceará. Todo o cultivo comercial desta curcubitácea nestas duas regiões é realizado sob condições de irrigação. Assim, medidas de uso eficiente da água tornam-se essenciais para esta cultura. A melhoria na eficiência do uso da água irá depender principalmente de um manejo que entregue à planta somente a quantidade de água necessária para o seu pleno desenvolvimento. Neste sentido, o presente trabalho teve por objetivo avaliar o crescimento das plantas, o estado hídrico, as trocas gasosas e a produção do meloeiro amarelo cultivado sob diferentes lâminas de irrigação. Para tanto, conduziram-se dois experimentos no Campo Experimental do Curu, no município de Paraipaba, CE, utilizando híbrido Gold Mine, com espaçamento de 2,0 m x 0,4 m e irrigado por gotejamento. O primeiro experimento consistiu na avaliação semanal do crescimento das plantas em resposta à aplicação de três diferentes lâminas diárias de irrigação: 100% 80% e 120% (T1, T2 e T3 respectivamente) da lâmina calculada. No segundo experimento, além dos tratamentos citados anteriormente, foi inserido outro fator: turno de rega de 24 e 48 horas, com quatro repetições por tratamento. Neste, se avaliou as trocas gasosas, o potencial hídrico, os teores de carboidratos nas diversas partes das plantas e a produção e qualidade dos frutos. Em todos os tratamentos, as plantas apresentaram o menor potencial hídrico diário no período de 12h00min às 14h00min. Apesar de a condutância estomática decrescer ao longo do dia, a mesma se mantinha em valores suficientes para permitir uma taxa fotossintética praticamente constante, com leve redução após o meio dia e decréscimo acentuado somente após as 16h00min. Por sua vez, com exceção da transpiração, que foi mais alta nas plantas irrigadas a cada 48 horas, o turno de rega e as lâminas hídricas aplicadas não influenciaram as trocas gasosas das plantas. Da mesma forma, a produção, o tamanho e a qualidade dos frutos de meloeiro praticamente não foram influenciados pelos tratamentos aplicados. Assim, nas condições experimentais utilizadas, o acréscimo ou diminuição de 20% da lâmina de água calculada recomendada para o melão na região, não influenciou o desenvolvimento das plantas, nem tampouco a produção. Apenas a quantidade de sólidos solúveis totais (ºBrix) foi influenciada positivamente pelo o acréscimo de 20% da lâmina calculada, quando aplicada diariamente.
19

Mécanismes de défense chez les végétaux et notion d'élicitation : cas de Cucumis melo et d'un Stimulateur des Défenses Naturelles le «FEN560» / Elicitation of plant defense mechanisms : study of induced resistance in Cucumis melo elicited by FEN560, natural defense elicitor

Kati, Djamel Edine 29 January 2010 (has links)
Nos travaux de recherches de thèse portent sur une étude comparative entre le déclanchement des mécanismes de défense in planta de la plante de melon après élicitation biotique, et un traitement avec un produit ayant des propriétés de Stimulateur des Défenses Naturelles (SDN). Le pathosystème étudié est Cucumis melo - Fusarium Oxysporum melonis. L'éliciteur abiotique SDN utilisé codé FEN560 est un extrait de graines de fenugrec (Trigonella foenum-graecum). Les principaux travaux sont : 1) L'analyse des activités enzymatiques relatives au stress et caractérisation d'enzymes PR. 2) L'étude des métabolites du métabolisme secondaire, notamment la production l'accumulation des composés organiques volatiles (COV). 3) Une étude de l'expression de gènes candidats impliqués dans la production de ces PR-protéines et/ou dans les voie de signalisation est aussi entreprise ; Les principaux résultats se traduisent par (i) une précocité et intensité de l'induction des activités enzymatiques étudiées pour les deux variétés et pour les organes d'un même plant (ii) Le priming est généralement observé au niveau du site de la seconde élicitation (infection FOM) avec une induction remarquable des PR-protéines. (iii) L'élicitation est Systémique, car l'induction se transmet mais à moindre intensité sur les intervalles de temps étudiés. (iv) L'augmentation de l'émission des COV coïncide avec l'induction de la LOX. Il est aussi noté l'émission de nouvelles molécules connus par leurs propriétés antibiotique ou répulsive des insectes herbivores ou attractive des prédateurs d'insectes herbivores. Les résultats sur les expressions des gènes candidats sont corrélés avec les activités enzymatiques et la production des composés organiques. Il en est ressorti que l'induction de la résistance par le traitement par pulvérisation de FEN560 est similaire au phénomène de « primig » dans la résistance systémique induite. / This work is a comparative study between defense mechanisms in melon plant induced by biotic elicitor and treatment by plant extract having simulative proprieties of plant defense mechanisms. The studied pathosystème is Cucumis melo - Fusarium oxysporum fsp melonis. The used plant extract elicitor is named FEN560, it is from fenugreek seeds (Trigonella foenum-graecum). The main works were: 1) Analysis of the enzymatic activities relating to the stress and characterization of PR-proteins sch as peroxidases and chitinases. The lipoxygenase (LOX), the key enzyme of oxylipins biosynthesis and phenylalanine ammonia-lyase, the key enzyme of the phenylpropanoids pathway, were also studyed. 2) The study of the metabolites of the secondary metabolism, in particular accumulation of volatile organic compounds (VOC). 3) A study of expression candidate genes implied in the production of Pr-proteins and the induced resistance pathways is also undertaken. The main results: (i) precocity and intensity of enzymatic activities induction for the two varieties after inoculation of pretreated plants (ii) the priming is generally observed in the site of the second elicitation with a remarkable induction of PR-proteins. (iii) The elicitation induced by FEN560 is systemic; because induction is transmitted between roots and shoots (iv) The modification of VOC emissions coincides with the induction of the LOX activity. It is also noticed the emission of new molecules known for their antibiotic properties or repulsive of the insects herbivorous or attractive of predatory of herbivorous insects. The results on the genes candidates' expression are in general correlated with the enzymatic activities and the production of the volatile organic compounds through LOX activity. In brief, the induction of resistance by the treatment by FEN560 is similar to the phenomenon of &quot;primig&quot; in induced systemic resistance.
20

Marcha de absorção e balanço de nutrientes no sistema soloplanta para o meloeiro fertirrigado. / Soil absorption and nutrient balance in the soil-plant system for the fertirrigated melon.

OLIVEIRA, Saul Ramos de. 21 May 2018 (has links)
Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-05-21T14:55:14Z No. of bitstreams: 1 SAUL RAMOS DE OLIVEIRA - DISSERTAÇÃO PPGHT - 2017.pdf: 1048451 bytes, checksum: b2812626d0423632bee874177b20ee40 (MD5) / Made available in DSpace on 2018-05-21T14:55:14Z (GMT). No. of bitstreams: 1 SAUL RAMOS DE OLIVEIRA - DISSERTAÇÃO PPGHT - 2017.pdf: 1048451 bytes, checksum: b2812626d0423632bee874177b20ee40 (MD5) Previous issue date: 2017 / Um dos fatores que mais contribuem para o encarecimento da produção do meloeiro é o custo com fertilizantes. Assim, para a otimização das doses a serem aplicadas visando a máxima produtividade econômica, faz-se necessário conhecer as demandas nutricionais da cultura, bem como as quantidades exigidas dos nutrientes em fases fenológicas chaves. No presente trabalho objetivou-se determinar a marcha de acumulação de macro e de micronutrientes e o balanço nutricional do meloeiro cultivado sob fertirrigação. O experimento foi realizado em área pertencente à Empresa Ecofértil Agropecuária LTDA localizada no município de Aracati (CE). O experimento foi instalado em delineamento de blocos casualizados com 9 tratamentos, correspondentes a 9 períodos de avaliação 14, 21, 28, 35, 42, 49, 56, 63, 70 dias após transplantio (DAT) com quatro repetições. A parcela útil para fins de coleta foi constituída de 8 plantas tornando-se as quatro centrais de cada fileira. Em intervalos de sete em sete dias, as plantas foram coletadas e separadas em folha, caule, fruto e semente para fins da determinação de N, P, K, Ca, Mg, S, Fe, Mn, B, Zn e Cu, para a quantificação dos totais acumulados destes nutrientes. Na ocasião da coleta de planta, uma amostra de solo foi coletada em cada parcela para a determinação dos nutrientes. De acordo com os resultados, o acúmulo de massa seca nas partes reprodutivas foi maior que nas partes vegetativas, sendo os frutos os órgãos de maior acúmulo de massa seca. Já a marcha de acúmulo de nutrientes seguiu a seguinte ordem: K>Ca>N>Mg>P>S>Fe>Cu>B>Zn>Mn. Os valores do balanço nutricional foram negativos para o potássio, nitrogênio e cobre, sendo recomendado ajuste na fertirrigação em relação a esses nutrientes. / One of the factors that contribute the most to the increase in melon production is the cost of fertilizers. Thus, to optimize the doses to be applied aiming at maximum economic productivity, it is necessary to know the nutritional demands of the crop, as well as the required quantities of the nutrients in key phenological phases. The objective of this study was to determine the progression of macro and micronutrients accumulation and the nutritional balance of the melon cultivated under fertirrigation. The experiment was carried out in an area belonging to the Company Ecofértil Agropecuária Ltda located in the city of Aracati (CE). The experiment was carried out in a randomized block design with 9 treatments, corresponding to 9 evaluation periods 14, 21, 28, 35, 42, 49, 56, 63, 70 days after transplanting (DAT) with four replications. The useful part for the purpose of collection was constituted of 8 plants becoming the four centers of each row. At intervals of seven days, the plants were collected and separated into leaf, stem, fruit and seed for the determination of N, P, K, Ca, Mg, S, Fe, Mn, B, Zn and Cu, for The quantification of accumulated totals of these nutrients. At the time of plant collection, a soil sample was collected in each plot to determine the nutrients. According to the results, the accumulation of dry mass in the reproductive parts was higher than in the vegetative parts, the fruits being the organs with the highest accumulation of dry mass. However, the nutrient accumulation progressed in the following order: K> Ca> N> Mg> P> S> Fe> Cu> B> Zn> Mn. The values of the nutritional balance were negative for potassium, nitrogen and copper, being recommended adjustment in fertirrigation in relation to these nutrients.

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