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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.
51

Desenvolvimento de marcador molecular para resistência a Tobacco mosaic virus e herança da resistência a Meloidogyne incognita raça 3 em tabaco / Development of molecular marker for resistance to Tobacco mosaic virus and heredity of resistance to Meloidogyne incognita race 3 in tobacco

Raphaelle Komatsu Dalla Valle 05 September 2008 (has links)
Este projeto objetivou desenvolver um marcador molecular ligado ao gene de resistência a Tobacco mosaic virus (TMV), em vista da necessidade de aprimorar os métodos de melhoramento de plantas para atender crescentes demandas de produtividade. O outro objetivo deste trabalho foi a avaliação de uma população segregante F2 e de retrocruzamento (RC1F1) a Meloidogyne incognita raça 3, oriunda do cruzamento das cultivares comerciais Coker 176 (C176) e Coker 371 Gold (C371G). Para o desenvolvimento do marcador ligado ao gene de resistência a TMV, o gene N, foram desenvolvidos iniciadores específicos para regiões conservadas (TIR, NBS e LRR) deste gene com base em sua seqüência. Estes iniciadores foram utilizados para amplificar um marcador cuja ligação ao referido gene foi confirmada em 200 indivíduos de população segregante F2 oriunda do cruzamento entre uma linhagem resistente (Coker176) e outra suscetível ao vírus (Kentucky326). A proporção entre o número de plantas resistentes e suscetíveis (154:46) não diferiu estatisticamente daquela esperada no caso de segregação de um gene dominante de resistência, que seria de 3:1. Os resultados indicaram que o marcador e o gene estão proximamente ligados segundo taxa de recombinação, que foi de 1%. Na avaliação da hereditariedade a M.incognita utilizou-se 141 indivíduos da população segregante F2 oriunda do cruzamento entre uma linhagem resistente (Coker176) e suscetível (Coker 371G) e 138 indivíduos de RC1F1 ([C176 X C371G] X C371G). Os resultados obtidos entre a proporção entre o número de plantas resistentes e suscetíveis da população F2 (102:39) e da RC1F1 (67:71) não diferiu estatisticamente daquela esperada no caso de segregação de um gene dominante de resistência. / The aim of this study is to develop a molecular marker linked to the resistant gene to Tobacco mosaic virus (TMV) considering the necessity to improve plant breeding to meet growing demands of productivity. The other goal of this study is to evaluate the mode of inheritance of an F2 segregating population and backcross (BCF1) population of Meloidogyne incognita race 3 originated from cross breeding between commercial cultivars Coker 176 and Coker 371 Gold. For the development of the marker linked to the TMV resistant gene, the N gene, specific primers of this gene were developed for conserved regions (TIR, NBS and LRR) based on their sequence. These primers were used to amplify a marker whose connection with the aforementioned gene was confirmed in 200 individuals in a segregating F2 population originated from the cross breeding between a resistant cultivar (Coker176) and another cultivar which is susceptible to the virus (Kentucky326). The proportion between the number of resistant and susceptible plants (154:46) did not statistically differ from the one expected in the segregation of one dominant resistance, which would be a 3:1 segregation ratio. The results indicated that the marker and the gene are narrowly linked according to recombination ratio 1%. In the heredity evaluation of resistance to M.incognita 141 plants of the segregating F2 population originated from the cross breeding of a resistant (Coker176) and susceptible cultivar (Coker 371G) and 138 plants of backcross BC1F1 ([C176 X C371G) X C3371G) were used. The outcome of the proportion between the number of resistant and susceptible plants of segregating F2 (102:39) and BC1F1 population (67:71) were not statistically different from the ones expected for a monogenic dominant resistance.
52

Influence of container-type and positioning on growth of tomato plants and suppression of meloidogyne javanica exposed to biomuti and afrikelp

Sebati, Mmagadima Lauraine January 2019 (has links)
Thesis (M. A. Agriculture (Plant Protection)) -- University of Limpopo, 2019 / The influence of cultural practices can be modified by environmental conditions such as container-type or positioning. The objective of the study was to determine whether container-type and positioning would have an influence on the growth of tomato plants and suppression of Meloidogyne javanica exposed to biomuti (Trial 1) and Afrikelp (Trial 2). Different container-types were filled with approximately 10.4 L growing mixture comprising steam-pasteurised sandy loam soil and Hygromix-T at 3:1 (v/v) ratio. The containers were established in microplots at 0.6 m × 0.6 m spacing, with treatments being brown pot-below; brown pot-above, black pot-below, black pot-above, plastic bag-above and plastic bag-below. Tomato (Solanum lycopersicum L.) cv. 'Floradade' seedlings were each transplanted and irrigated with 500 ml chlorine-free tapwater every other day. Seven days after transplanting, each plant was inoculated with 2000 eggs and second-stage juveniles (J2) of M. javanica. Biomuti and Afrikelp, obtained from the Agricultural Research Council (ARC) Vegetable, Ornamentals and Plants (VOP), were applied in separate trials weekly at 2.5%. At 56 days after inoculation, plant growth including selected nutrient elements and nematode variables were measured. Data were subjected to analysis of variance, with separation of means achieved using Fisher’s Least Significant Difference test at the probability level of 5%. In the biomuti trial, container-type and positioning had a significant effect on plant height, fruit number, dry root mass, dry shoot mass and fruit mass, contributing 82, 48, 44, 85 and 89% in total treatment variation (TTV) of the respective variables. Relative to brown pot-below; black pot above, plastic bag-above and brown pot-above reduced plant variables, whereas treatment effects were not significant on nematode variables. In the Afrikelp trial, trends where similar to those in biomuti, treatments had highly significant effects on xvi plant height, dry root mass, dry shoot mass and gall rating, contributing 91, 88, 66 and 60% in TTV of the respective variables. Relative to brown pot-below; black pot above, plastic bag-above and brown pot-above reduced the plant variables, but had no significant effects on nematode variables. Generally, plastic bags and polyethylene pots below-ground improved most plant growth variables when compared to those in containers positioned above-ground.
53

Étude de la régulation du transcriptome de nématodes parasites de plante, les nématodes à galles du genre Meloidogyne / Comprehensive transcriptome profiling of root-knot nematodes during plant infection and characterisation of species specific trait

Nguyen, Chinh Nghia 08 December 2016 (has links)
Les nématodes à galles (RKN) du genre Meloidogyne spp. sont des parasites obligatoires des plantes qui induisent la formation d’un site nourricier spécialisé au sein des racines. Mon projet de thèse a pour objectif d’identifier des gènes spécifiques de ces nématodes qui sont impliqués dans le parasitisme en se focalisant sur des protéines sécrétées ou effecteurs. La technologie de séquençage Illumina a été utilisée pour comparer les transcriptomes de M. incognita au cours de son cycle de vie. A partir de 307 gènes surexprimés dans -au moins- un stade du cycle de vie, nous avons sélectionné 14 candidats d’effecteurs. Des expériences de RT-qPCR, d’hybridation in situ et d’ARN interférence ont permis de confirmer le profil d’expression, de localiser l’expression des effecteurs et d’étudier leur rôle dans la pathogénicité. Ce travail a permis de démontrer le rôle important d’une petite protéine, MiSCR1, dans les stades précoces du parasitisme. Parallèlement, nous avons réalisé l’assemblage de novo du transcriptome de M. enterolobii, qui représente une nouvelle menace pour l’agriculture mondiale du fait de sa capacité à se reproduire sur la majorité des plantes résistantes aux autres RKN. Les premières comparaisons avec d'autres RKN nous ont permis d'identifier, non seulement des effecteurs en commun, mais aussi ceux qui sont spécifiques à certaines espèces de RKN et qui pourraient expliquer des différences de gamme d'hôtes. En conclusion, les analyses de transcriptomes de RKN ont permis de caractériser des nouveaux effecteurs candidats impliqués dans la pathogénicité, et d’apporter de nouvelles connaissances pour le développement de méthodes de lutte contre ces bioagresseurs / Root-knot nematodes (RKN) are obligate endoparasites that maintain a biotrophic relationship with their hosts inducing specialized feeding cells. My PhD project aims to identify RKN genes specifically involved in plant parasitism with an emphasis on genes encoding new secreted proteins, named effectors. Using Illumina RNA-seq technologies, we compared transcriptomes of Meloidogyne incognita during its life cycle. From 307 genes over-expressed at -at least- one stage of the life cycle, we selected 14 effector candidates. RT-qPCR, in situ hybridisation and siRNA soaking experiments were carried out to confirm their expression profile, localize the spatial expression of these candidates in the nematode and to study their role in pathogenicity. The silencing of the dorsal gland specific-Minc18876 gene and its paralogues resulted in a significant, reproducible decrease in the number of egg masses, demonstrating a potentially important role for the small cysteine-rich effector, MiSCR1, it encodes in early stages of giant cell formation. In parallel, we perform a de novo assembly of M. enterolobii transcriptome. This RKN species represents a new threat for the agriculture worldwide because of its ability to reproduce on the majority of known RKN-resistant plants. First comparisons with others RKN allowed us to identify, not only the common set of effectors, but also those specific to some RKN species and possibly involved in host range differences. In conclusion, the transcriptome profiling of RKNs allowed the characterisation of new candidate effectors involved in the plant pathogenicity, and provided a better knowledge for the development of new methods to control these pests
54

Integrated system for the management of meloidogyne javanica in potato production

Seshweni, Mosima Dorcus January 2016 (has links)
Thesis (M. Agricultural Management (Animal Production)) -- University of Limpopo, 2016 / Cultivated potato (Solanum tuberosum L.) cultigens do not have resistant genotypes to root-knot (Meloidogyne species) nematodes. Currently, efforts are underway to introgress nematode resistance in potato breeding programmes, whereas other environment-friendly nematode management strategies are being assessed in various cultigens. Nemafric-BL and Nemarioc-AL phytonematicides have being researched and developed for managing the root-knot nematode whereas Biocult Mycorrhizae are intended to enhance crop productivity through improved absorption of P, which is inherently low in most South African soils. The objectives of the study, therefore, were: (1) to determine the interactive effects of Nemacur (N), Biocult Mycorrhizae (B) and Nemarioc-AL or Nemafric-BL phytonematicide (P) on population densities of M. javanica and growth of potato plants, (2) to investigate the effects of Nemacur (N), Velum (V), Biocult Mycorhizae (B) and Nemarioc-AL or Nemafric-BL phytonematicide (P) on population densities of M. javanica and growth of potato plants. For the microplot experiment, potato cv. ‘Mondial G3’ seeds were sown in 25 cm-diameter plastic pots with 5 000 ml steam-pasteurised river sand and Hygromix-T at 3:1 (v/v) growing mixture in autumn (March-May) 2015. Pots were buried 80% deep into the soil in with 0.5 m inter-row and 0.5 m intra-row spacing. Potato cv. ‘Mondial G3’ seeds were dipped in a mixture of Mancozeb with a wettener for disease management prior to sowing. Appropriate treatments were applied soon after emergence of leaves. Each plant was inoculated by dispensing a mixture of 5 000 eggs and M. javanica J2. Eight treatments, control (N0B0P0), Nemacur (N1B0P0), Biocult (N0B1P0), phytonematicide (N0B0P1), Nemacur × Biocult (N1B1P0), Nemacur × phytonematicide (N1B0P1), Biocult × phytonematicide (N0B1P1) and Nemacur × Biocult × phytonematicide (N1B1P1), were arranged in a randomised complete block xxvi design (RCBD) with 8 replications (n= 64). Under field conditions the study was conducted in summer (October 2015 - January 2016), with 30-cm furrows dug and potato seeds placed in the soil with 30 cm inter-row and 40 cm intra-row spacing. The four treatments, namely, (1) untreated control, (2) Nemacur or Velum (3) Biocult Mycorrhizae and (4) Nemarioc-AL or Nemafric-BL phytonematicide, were arranged in RCBD, replicated three times for the Velum experiment and five times for the Nemacur experiment. At 56 days after inoculation, the second order interaction (N1B1P1) was highly significant (P ≤ 0.01) for eggs in root and total nematodes, contributing 13 and 12% to total treatment variation (TTV) of the two variables, respectively, in the Nemarioc-AL phytonematicide study. Relative to untreated control, the second order interaction (N1B1P1) reduced eggs in root and total nematodes by 42 and 36%, respectively. In both Nemarioc-AL and Nemafric-BL phytonematicide experiments, the combination of phytonematicide and Biocult Mycorrhizae reduced gall rating. Nemacur, Biocult and Nemarioc-AL phytonematicide, the treatment effects were highly significant on eggs, J2 in root and total nematodes, contributing 53, 68 and 57% to TTV of the three variables, respectively. Nemacur, Biocult and Nemafric-BL phytonematicide treatments each was not significant (P ≤ 0.05) for nematodes variables. Both treatments for Nemacur, Biocult and Nemarioc-AL or Nemafric-BL phytonematicides were significant for gall rating, contributing 92 and 70% to TTV of the variable, respectively. In Nemarioc-AL phytonematicide, relative to the untreated control, gall rating was reduced by 48 to 56%, whereas in Nemafric-BL phytonematicide the variable was reduced by 33 to 56%. In the Velum study, Biocult and Nemarioc-AL or Nemafric-BL phytonematicide, the treatment effects in both experiments were highly significant (P ≤ 0.01) on eggs in root, contributing 88% to TTV of the variable. Both treatments from Nemarioc-AL xxvii and Nemafric-BL phytonematicides had no significant effects on all plant variables measured. In microplot, the second order interaction (Nemacur × Biocult × Nemarioc-AL phytonematicide) was highly significant for nematode eggs in root and total nematode. In a three-way matrix, the N1B1P1 interaction had the highest effects on eggs, followed by Biocult alone, then Nemacur alone and then the phytonematicide. The same trend was observed in the three-way matrix for total nematodes. However, in two-way matrix for eggs, Biocult outperformed Nemacur, as was the phytonematicide on J2. In another microplot study, the second order interaction (Nemacur × Biocult × Nemafric-BL phytonematicide) was significant for J2 in soil and roots, with the three-way matrix showing, that Biocult alone had higher effects than the N1B1P1 interaction on J2 in root. A three-way matrix also showed that Nemacur was outperformed by the phytonematicide alone, Biocult alone and the interactions on J2 in soil. In conclusion, Nemarioc-AL and Nemafric-BL phytonematicides could each be used with Biocult Mycorrhizae in the management of population densities of M. javanica in potato production since the impact from Nemacur which is a synthetic nematicide does not have that much difference from that of phytonematicides interacted with Biocult Mycorrhizae. / Agricultural Research Council
55

O Nematóide de galha da goiabeira (Meloydogyne mayaguensis Ramah & Hirschmann, 1988): identificação, hospedeiros e ação patogenica sobre goiabeiras

Almeida, Eduardo José [UNESP] 12 December 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-12Bitstream added on 2014-06-13T19:04:54Z : No. of bitstreams: 1 almeida_ej_dr_jabo.pdf: 2925633 bytes, checksum: 1794e969fffc6c2ce4cdd74354b559fc (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho teve os objetivos de estudar comparativamente os caracteres morfológicos e morfométricos úteis para distinção entre Meloidogyne mayaguensis e M. incognita; quantificar os danos causados à goiabeira ‘Paluma’, em formação, por M. mayaguensis em níveis crescentes de inóculo; caracterizar o desbalanço nutricional e a fenologia da goiabeira ‘Paluma’ face à infecção pelo nematóide; avaliar a hospedabilidade de outras frutíferas e plantas invasoras a esse patógeno; estudar a flutuação populacional do nematóide em pomar de goiabeira ‘Paluma’; prospectar materiais resistentes a M. mayaguensis dentre diversos acessos de Psidium guajava e Psidium spp. e avaliar a compatibilidade desses materiais como porta-enxerto para goiabeira ‘Paluma’. Os dados indicam que a morfologia do padrão perineal e da região labial dos machos são suficientes para a distinção segura entre M. mayaguensis e M. incognita. As medidas do diâmetro do tronco, comprimento das três pernadas, massa fresca e seca da parte aérea, retirada nas podas, área de folhas individuais, comprimento, largura, número por planta e massa dos frutos foram inversamente proporcionais aos níveis de inóculo de 0, 10, 100, 1.000 e 10.000 ovos e juvenis/planta. Os teores de N, P e K decresceram de folhas sem sintomas para folhas com o sintoma leve e severo, nas análises realizadas em fevereiro e agosto. / This work had the objectives of to study the morphologic characters and useful morfometric comparatively for distinction between Meloidogyne mayaguensis and M. incognita; to quantify the damages caused to the guava 'Paluma', in growing, for M. mayaguensis in growing levels of inocula; to characterize the nutritional imbalance and the fenology of the guava 'Paluma' face to the infection for the nematode; to evaluate the host suitability of other fruitful ones and its weeds to that pathogen; to study the population fluctuation of the plant parasitic nematode in guava orchard 'Pedro Sato'; resistant material prospect to M. mayaguensis between several accesses of Psidium guajava and Psidium spp. and to evaluate the compatibility of those materials as rootstock for guava 'Paluma'. The data indicate that the morphology of the perineal pattern and of the labial area of the males they are enough for the distinction it holds between M. mayaguensis and M. incognita. The measures of the diameter of the log, length of the three blanches, fresh and dry mass of the blanches, retreat in the pruning, area of individual leaves, length, width, number for plant and mass of the fruits was inversely proportional at the levels of inocula of 0; 10; 100; 1,000 and 10,000 eggs and juveniles/plant. The tenors of N, P and K decreased of leaves without symptoms for leaves with the light and severe symptom, in the analyses accomplished in February and August. The Ca had your concentration increased with the worsening of the symptoms, in February and August and Mg only in August. Sulfur had a larger concentration in leaves without symptoms, in February. In August, the leaves with severe symptoms presented larger concentrations of S.
56

Reação de genótipos de arroz de terras altas a Meloidogyne javanica

Matos, Dilânia Lopes de 21 February 2014 (has links)
Submitted by Valquíria Barbieri (kikibarbi@hotmail.com) on 2018-03-19T20:47:57Z No. of bitstreams: 1 DISS_2014_Dilania Lopes de Matos.pdf: 684417 bytes, checksum: 4a602d4c8c97f6b4eabd1bfe8db64e3e (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2018-04-10T18:14:50Z (GMT) No. of bitstreams: 1 DISS_2014_Dilania Lopes de Matos.pdf: 684417 bytes, checksum: 4a602d4c8c97f6b4eabd1bfe8db64e3e (MD5) / Made available in DSpace on 2018-04-10T18:14:51Z (GMT). No. of bitstreams: 1 DISS_2014_Dilania Lopes de Matos.pdf: 684417 bytes, checksum: 4a602d4c8c97f6b4eabd1bfe8db64e3e (MD5) Previous issue date: 2014-02-21 / CAPES / Nematoides do gênero Meloidogyne, constituem-se em importante grupo de fitoparasitas causadores de danos em culturas de grande importância econômica. Este trabalho teve como objetivo avaliar a reação de genótipos de arroz de altas a M. javanica, realizado em condições de casa de vegetação. Foram utilizados genótipos de arroz de terras altas, oriundos do programa de melhoramento genético da Embrapa Arroz e Feijão. O delineamento experimental utilizado foi o inteiramente casualizado com 37 tratamentos, sendo 36 genótipos de arroz e uma cultivar de soja (BRSMG 760RR) utilizada como testemunha suscetível, em quatro repetições cada. A população de nematoide das galhas foi mantida em plantas de tomateiro. As plantas de arroz foram inoculadas com 1000 ovos + juvenil segundo estádio (J2), 30 dias após semeadura. Aos 60 dias após inoculação, foram avaliadas as seguintes variáveis: Massa Fresca da Raiz (MFR), massa fresca e seca da parte aérea, número de massa de ovos, número de ovos + J2 por sistema radicular, para determinação do índice de massa de ovos (IMO) e fator de reprodução (FR). Foi verificado os coeficientes de correlação linear entre as variáveis IMO x FR, IMO x MFR e MFR x Pf. Os resultados obtidos indicaram que 72% dos genótipos de arroz destacaram-se positivamente, com comportamento de resistência a M. javanica. Verificou-se que nem sempre uma maior população de nematoides no sistema radicular, indica menor massa de raiz e área foliar. Além disso, a avaliação somente do índice de massa de ovos não é suficiente para determinação de resistência ou suscetibilidade a M. javanica de genótipos de arroz, sendo necessário avaliar o fator reprodução. Todas as correlações foram significativas e positivas, indicando que o comportamento dos parâmetros avaliados foi sempre no mesmo sentido. / Nematodes of the genus Meloidogyne, constitute an important group of plant parasites that cause damage to crops of economic importance. This study aimed to evaluate the resistance of upland rice genotypes to M. javanica, conducted in a greenhouse. Were used genotypic materials upland rice, originating from the breeding program of Embrapa Arroz e Feijão. The experimental design was completely randomized with 37 treatments and 36 genotypes of rice and cultivar soybean (BRSMG 760RR) as susceptible, and four replications each. The root-knot nematode populations were maintained on tomato plants, tobacco and soybeans. The rice plants were inoculated with 1000 eggs + second-stage juvenile (J2), 30 days after sowing. After 60 days inoculation the following variables were evaluated: fresh root mass (MFR), fresh and dry weight of shoots, number of egg mass, number of eggs + J2 per root system, for determining mass index eggs (IMO) and reproduction factor (FR), obtained by dividing the final population (Pf) and initial (Pi) of the nematode (FR = Pf / Pi). Was found the coefficient of linear correlation between the variables IMO x FR, IMO x MFR e MFR x Pf. The results indicated that 72% of the xiii genotypes of rice stood out positively with resistance the M. javanica, it was found that a larger population of nematodes in root, does not indicate lower root mass and leaf area. Furthermore, only mass index egg is not sufficient to determine the resistance or susceptibility of rice genotypes the M. javanica, being necessary to evaluate the reproduction factor. All correlations were significant and positive, indicating that the behavior of the evaluated parameters was always in the same direction.
57

O Nematóide de galha da goiabeira (Meloydogyne mayaguensis Ramah & Hirschmann, 1988) : identificação, hospedeiros e ação patogenica sobre goiabeiras /

Almeida, Eduardo José. January 2008 (has links)
Resumo: Este trabalho teve os objetivos de estudar comparativamente os caracteres morfológicos e morfométricos úteis para distinção entre Meloidogyne mayaguensis e M. incognita; quantificar os danos causados à goiabeira 'Paluma', em formação, por M. mayaguensis em níveis crescentes de inóculo; caracterizar o desbalanço nutricional e a fenologia da goiabeira 'Paluma' face à infecção pelo nematóide; avaliar a hospedabilidade de outras frutíferas e plantas invasoras a esse patógeno; estudar a flutuação populacional do nematóide em pomar de goiabeira 'Paluma'; prospectar materiais resistentes a M. mayaguensis dentre diversos acessos de Psidium guajava e Psidium spp. e avaliar a compatibilidade desses materiais como porta-enxerto para goiabeira 'Paluma'. Os dados indicam que a morfologia do padrão perineal e da região labial dos machos são suficientes para a distinção segura entre M. mayaguensis e M. incognita. As medidas do diâmetro do tronco, comprimento das três pernadas, massa fresca e seca da parte aérea, retirada nas podas, área de folhas individuais, comprimento, largura, número por planta e massa dos frutos foram inversamente proporcionais aos níveis de inóculo de 0, 10, 100, 1.000 e 10.000 ovos e juvenis/planta. Os teores de N, P e K decresceram de folhas sem sintomas para folhas com o sintoma leve e severo, nas análises realizadas em fevereiro e agosto. / Abstract: This work had the objectives of to study the morphologic characters and useful morfometric comparatively for distinction between Meloidogyne mayaguensis and M. incognita; to quantify the damages caused to the guava 'Paluma', in growing, for M. mayaguensis in growing levels of inocula; to characterize the nutritional imbalance and the fenology of the guava 'Paluma' face to the infection for the nematode; to evaluate the host suitability of other fruitful ones and its weeds to that pathogen; to study the population fluctuation of the plant parasitic nematode in guava orchard 'Pedro Sato'; resistant material prospect to M. mayaguensis between several accesses of Psidium guajava and Psidium spp. and to evaluate the compatibility of those materials as rootstock for guava 'Paluma'. The data indicate that the morphology of the perineal pattern and of the labial area of the males they are enough for the distinction it holds between M. mayaguensis and M. incognita. The measures of the diameter of the log, length of the three blanches, fresh and dry mass of the blanches, retreat in the pruning, area of individual leaves, length, width, number for plant and mass of the fruits was inversely proportional at the levels of inocula of 0; 10; 100; 1,000 and 10,000 eggs and juveniles/plant. The tenors of N, P and K decreased of leaves without symptoms for leaves with the light and severe symptom, in the analyses accomplished in February and August. The Ca had your concentration increased with the worsening of the symptoms, in February and August and Mg only in August. Sulfur had a larger concentration in leaves without symptoms, in February. In August, the leaves with severe symptoms presented larger concentrations of S. / Orientador: Jaime Maia dos santos / Coorientador: Antonio Baldo Geraldo Martins / Banca: José Antonio Alberto da Silva / Banca: Antonio Lúcio Mello Martins / Banca: Luiz Carlos Camargo Barbosa Ferraz / Banca: João Carlos de Oliveira / Doutor
58

Meloidogyne exigua: distribuição espacial, nível de infestação, mortalidade de seringueiras e controle com plantas antagonistas

Gontijo, Luciana Nunes 18 February 2017 (has links)
A infestação de áreas com Meloidogyne exigua é um dos principais fatores limitantes ao desenvolvimento da heveicultura brasileira. Estudos anteriores demonstraram que o nematoide afeta o crescimento da seringueira, reduzindo o desenvolvimento de árvores que estão em fase produtiva podendo comprometer até mesmo a sua sobrevivência. Nesse contexto, o objetivo do presente estudo foi avaliar a distribuição espacial e nível populacional de M. exigua em um seringal e seu controle com plantas antagonistas. Para tanto, foram montados dois experimentos. O primeiro avaliou a distribuição espacial e o nível populacional do nematoide de galha em um plantio comercial de seringueira no Triângulo Mineiro, Minas Gerais. Constatou-se que o nível populacional de M. exigua, na área estudada, concentrou-se em focos elípticos – reboleiras – e sua distribuição espacial era do tipo agregada. O segundo experimento avaliou o efeito das plantas antagonistas Arachis repens, Brassica juncea, Brassica napus, Crotalaria spectabilis, Tagetes sp. consorciadas com mudas de seringueira no controle de Meloidogyne exigua. As plantas Arachis repens, Brassica juncea, Brassica napus e Tagetes sp. demonstraram efeito antagônico sobre a população do nematoide. Os resultados obtidos evidenciam a importância do manejo para expansão da heveicultura brasileira. / The infestation of nematodes of the genus Meloidogyne is one of the main limiting factors for the expansion of Brazilian rubber tree plantations. Previous studies have shown that this root-knot nematode affects growth of the rubber tree, thus reducing the development of trees in the production phase and even jeopardizes its survival. In this context, the objective of this study was to evaluate the spatial distribution of Meloidogyne exigua in a rubber tree plantation and its control with antagonistic plants. In order to perform this, two experiments were done. The first one evaluated the population density of the root-knot nematode in a commercial rubber tree plantation in Triângulo Mineiro, Minas Gerais. The population density of M. exigua, in the studied area, was concentrated in elliptic foci with a clustered spatial distribution. The second experiment evaluated the effect of the antagonistic plants Arachis repens, Brassica juncea, Brassica napus, Crotalaria spectabilis, and Tagetes sp. on the management of M. exigua in rubber tree seedlings. Both Brassica juncea and Arachis repens showed antagonistic effect on nematode population. The results obtained highlight the importance of proper nematode management for the expansion of Brazilian rubber tree plantations. / Dissertação (Mestrado)
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"Reação de famílias de cana-de-açúcar (Saccharum sp.) em relação a Meloidogyne incognita (Kofoid & White, 1919) Chitwood, 1949" / Reaction of sugarcane families (Saccharum sp.) to Meloidogyne incognita (Kofoid & White, 1919) Chitwood,1949

TEIXEIRA, Renato Andrade 10 February 2009 (has links)
Made available in DSpace on 2014-07-29T16:24:16Z (GMT). No. of bitstreams: 1 Dissertacao Renato Andrade Teixeira.pdf: 356174 bytes, checksum: 5bb378867a5b03e9c3111ec9caa39bde (MD5) Previous issue date: 2009-02-10 / The sugarcane crop has a special significance to the Brazilian economy that is a leading producing country. This crop is attacked by several pathogens and, amongst them are the nematodes of the genera Meloidogyne, that reduces the sugarcane yield. The use of chemical control, crop rotation, use of antagonistic plants and genetic control by introducing resistant source genes as control measures have been searched. In this work families of sugarcane were evaluated with the purpose to identify the plant reaction to Meloidogyne icognita. The trials were set up in a greenhouse at Universidade Federal de Goias, Goiania, GO. The seedlings were obtained from seeds or buds from the different crosses tested. These seedlings were planted in sterilized substrate and artificially inoculated with M. incognita. In the trials evaluation the variable considered were fresh root weigh, final nematode population, reproduction factor (RF) and nematode population reduction in relation to the susceptible standart. Afterwards the families and individuals were ranked as highly susceptible (HS), susceptible (S), little resistant (LR), moderately resistant (MR), resistant (R) or highly resistant (HR). In the trial with plants originated from seeds, the crosses RB945961 x SP81-3250 and SP81-3250 x RB945961were ranked as LR, the others were S or HS. The RF ranged from 0.55 to 1.18. In the trial with plants originated from buds, the crosses RB92804 x RB813804, RB865547 x RB855156, CP70-330 x ? and IAC86-2210 x SP70-1078 were considered LR and the others S or HS. The RF ranged from 0.15 to 0.59. In both trials, the individual evaluation within the progenies there was higher frequency of individuals ranked as MR and R. / A cultura da cana-de-açúcar tem especial significado econômico para o Brasil, que lidera a lista dos países produtores. Esta cultura é atacada por vários patógenos e entre esses estão os nematóides do gênero Meloidogyne, que reduzem a produtividade da canade-açúcar. Diante disso, tem-se buscado, como medidas de controle, os produtos químicos, a rotação de culturas, a utilização de plantas antagônicas e o controle genético, pela introdução de fontes de resistência. Neste trabalho, avaliou-se famílias de cana-de-açúcar, a fim de identificar a reação das plantas ao ataque de Meloidogyne incognita. Os experimentos foram instalados em casa-de-vegetação da Universidade Federal de Goiás, no município de Goiânia, GO, onde, em substrato esterilizado, foram transplantadas as plântulas provindas de sementes e de gemas dos cruzamentos utilizados, sendo então realizada a inoculação artificial com M. incognita. Na avaliação dos experimentos foram consideradas as variáveis peso verde das raízes, população final do nematóide, fator de reprodução (FR) e porcentagem de redução do nematóide em relação ao padrão de suscetibilidade. Em seguida as famílias e os indivíduos foram classificados como altamente suscetível (AS), suscetível (S), pouco resistente (PR), moderadamente resistente (MR), resistente (R) ou altamente resistente (AR). Os cruzamentos RB945961 x SP81-3250 e SP81-3250 x RB945961, com plantas obtidas de sementes, foram classificados como PR e os demais, S ou AS. O FR variou de 0,55 a 1,18. No ensaio cujas plantas nos cruzamentos foram obtidas a partir de gemas, os cruzamentos RB928064 x RB813804, RB865547 x RB855156, CP70-330 x ? e IAC86-2210 x SP70-1078 foram considerados PR e os demais S ou AS. O FR variou de 0,15 a 0,59. Em ambos os ensaios, na avaliação individual dentro das progênies houve maior freqüência de indivíduos classificados como MR e R.
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Extrato de Crambe abyssinica e o constituinte alil isotiocianato no controle de Meloidogyne incognita e Meloidogyne javanica em tomateiro / Crambe abyssinica extract and allyl isothiocyanate constituent on control Meloidogyne incognita and control Meloidogyne javanica in tomato plants

Roncato, Sidiane Coltro 27 August 2015 (has links)
Made available in DSpace on 2017-07-10T17:40:52Z (GMT). No. of bitstreams: 1 Sidiane_Coltro_Roncato.pdf: 1950234 bytes, checksum: ab588be5ce6968a641dc1b750a09907e (MD5) Previous issue date: 2015-08-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this work was to study the effect of Crambe abyssinica leaf extract on Meloidogyne incognita and Meloidogyne javanica control in tomato plants, and the possible effect of allyl isothiocyanate component in this interaction. Five experiments were conducted. The first experiment was carried out with both Meloidogyne species in vitro: dried leaves of crambe (200 mg L-1) were added in the solvents: water for infusion and grinding, acetone, water + ethanol, methyl alcohol, hexane and chloroform. After the evaporation rotative, the aqueous extracts were analyzed in vitro for nematicide activity (hatching, mortality and motility of second stage juveniles (J2)). After the extracts with increased activity were tested at doses of 200, 300, 400 and 500 mg L-1 of crambe dry leaves. To quantify the allyl isothiocyanate in the extracts was used high performance liquid chromatography (HPLC). The second and third experiment were with M. incognita and hydroalcoholic extract to 250 mg L-1 was used, and each experiment was repeated twice, being the second time with the two best times of the first. The first repetition of the second experiment was conducted in factorial design (3x4+1) in a greenhouse, with three extract application routes: leaf; soil; leaf+soil, in four periods: before inoculation; on inoculation; after inoculation; and weekly up to 45 days and an additional treatment (inoculated and untreated control). In the second repetition, the factorial design was (3x2+1), three routes of application as mentioned above, and two periods (after inoculation and weekly). The third experiment includes the same treatments, however, to the application routes is added the immersion of the tomato roots. The fourth and fifth experiments were with M. javanica, using the same methodology described for the experiments with M. incognita. The results derived from the extracts of hydroalcoholic solution, methanol and trituration were more effective in the action against nematodes, however, the hydroalcoholic one caused higher mortality, with 93% and 64% for M. incognita and M. javanica, respectively. The greatest effect was on the dose of 250 mg L-1, and only the extracts obtained by methanol solution and the hydroalcoholic presented allyl isothiocyanate. When the hydroalcoholic extract was tested in a greenhouse in tomato plants, to M. incognita the applications via soil and weekly did not differ statistically from the applications soil+leaf for the analyzed variables. When the immersion of the tomato plants rooting system was added, weekly applications routes via root+soil and root+soil+leaf stood out, and nematode population in the soil was reduced by 75.55% and 71.95%, respectively, however, the second experiment confirmed the control only to the application via soil+root+leaf. For M. javanica, applications of the extract via soil+leaf weekly caused reduction of total galls on 46.15%. When added the immersion of the root system, the weekly application via root+soil+leaf reduced the egg masses and total galls on 60.95% and 27.95%, respectively. Therefore, crambe extract has potential to make up the integrated management of M. javanica and M. incognita on tomato plants / O objetivo deste trabalho foi estudar o efeito do extrato de folhas de Crambe abyssinica no controle de Meloidogyne incognita e Meloidogyne javanica em tomateiro e, possível atuação do componente alil isotiocianato nesta interação. Foram conduzidos cinco experimentos. O primeiro experimento foi realizado com ambas as espécies de Meloidogyne in vitro: folhas secas de crambe (200 mg L-1) foram adicionadas nos solventes: água para infusão e trituração, acetona, água+álcool etílico, álcool metílico, hexano e clorofórmio. Após a evaporação rotativa, os extratos aquosos foram analisados in vitro para atividade nematicida (eclosão, mortalidade e motilidade de juvenis de segundo estádio (J2)). Após, os extratos com maior atividade foram testados nas doses 200, 300, 400 e 500 mg L-1 de folhas secas de crambe. Para quantificar o alil isotiocianato nos extratos foi utilizada cromatografia líquida de alta eficiência (HPLC). O segundo e terceiro experimento foram com M. incognita e extrato hidroalcoólico à 250 mg L-1 foi utilizado e, cada experimento foi repetido duas vezes, sendo a segunda vez com as duas melhores épocas da primeira. A primeira repetição do segundo experimento foi conduzido em esquema fatorial (3x4+1) em casa de vegetação, com três vias de aplicação do extrato: foliar; solo; foliar+solo, em quatro épocas: antes da inoculação; na inoculação; após a inoculação; e semanalmente até 45 dias e um tratamento adicional (testemunha inoculada e não tratada). Na segunda repetição, o esquema fatorial foi (3x2+1), três vias de aplicação como citado anteriormente, e duas épocas (após a inoculação e semanalmente). O terceiro experimento contempla os mesmos tratamentos, porém, nas vias de aplicação é adicionado a imersão das raízes de tomateiro. O quarto e quinto experimentos foram com M. javanica, com a mesma metodologia descrita para os experimentos com M. incognita. Os resultados dos extratos originados da solução hidroalcoólica, metanólica e por trituração apresentaram-se mais efetivos na ação contra os nematoides, porém, o hidroalcoólico ocasionou maior mortalidade, com 93% e 64% para M. incognita e M. javanica, respectivamente. O maior efeito foi na dose de 250 mg L-1, e somente os extratos obtidos por solução metanólica e o hidroalcoólica apresentaram alil isotiocianato. Quando o extrato hidroalcoólico foi testado em casa de vegetação em plantas de tomateiro, para M. incognita as aplicações via solo e semanalmente não diferiram estatisticamente das aplicações via solo+folha para as variáveis analisadas. Quando foi adicionada a imersão do sistema radicular do tomateiro, aplicações semanais com as vias raiz+solo e raiz+solo+folha se destacaram, e a população do nematoide no solo foi reduzida em 75,55% e 71,95%, respectivamente, porém, o segundo experimento confirmou o controle apenas para a aplicação via raiz+solo+folha. Para M. javanica, aplicações do extrato via solo+folha semanalmente ocasionaram redução de galhas totais em 46,15%. Quando adicionada a imersão do sistema radicular, a aplicação semanal via raiz+solo+folha reduziu massa de ovos e galhas totais em 60,95% e 27,95%, respectivamente. Portanto, o extrato de crambe tem potencial para compor o manejo integrado de M. javanica e M. incognita em tomateiro

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