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Planta medicinal é qualquer planta que produza princípios ativos que possam ser utilizados com finalidade terapêutica. Essas plantas podem ser atacadas por pragas e doenças que comprometem suas propriedades curativas e a produção. Nesse sentido, o objetivo do presente trabalho foi avaliar a reação de boldo (Plectranthus barbatus), menta (Mentha spicata), penicilina (Alternanthera brasiliana), hortelã-pimenta (Mentha piperita) e citronela (Cymbopogon nardus) a Meloidogyne javanica. O experimento foi conduzido em casa de vegetação no campo experimental do Instituto Taquaritinguense de Ensino Superior (ITES), Taquaritinga, SP, a partir de mudas transplantadas para vasos de 5 L contendo substrato esterilizado. Realizou-se a inoculação nas mudas após 20 dias do transplante com 640 ovos + juvenis de segundo estádio (J2) por planta. Decorridos 90 dias após a inoculação, as raízes foram processadas para extração dos ovos e determinação do fator de reprodução (FR) do nematoide. Todas as plantas medicinais avaliadas foram resistentes (FR < 1) a M. javanica, podendo ser utilizadas em rotação de culturas em áreas com ocorrência desse nematoide. Medicinal plant is any plant that produces active principles that can be used for therapeutic purposes. These plants can be attacked by pests and diseases that compromise healing properties and production. In this sense, the aim of the present work was to evaluate the reaction of boldo (Plectranthus barbatus), mint (Mentha spicata), penicillin (Alternanthera brasiliana), peppermint (Mentha piperita), and citronella (Cymbopogon nardus) to Meloidogyne javanica. The experiment was carried out in a greenhouse in the experimental field of Instituto Taquaritinguense de Ensino Superior (ITES), municipality of Taquaritinga, São Paulo state, Brazil, using seedlings transplanted into 5 L pots containing sterilized substrate. The seedlings were inoculated 20 days after transplanting with 640 eggs + second stage juveniles (J2) per plant. After 90 days after inoculation, the roots were processed to extract the eggs, and determine the nematode reproduction factor (RF). All medicinal plants evaluated were resistant (RF < 1) to M. javanica, and can be used in crop rotation in areas with occurrence of this nematode. Made available in DSpace on 2022-09-15T17:06:26Z (GMT). No. of bitstreams: 1 27361.pdf: 213035 bytes, checksum: ae0e75ab8d8d2b0d0175dbf60ddd389d (MD5) Previous issue date: 2022

Plant diseases can negatively impact the production and sale of agricultural crops in a given region. Because it is a border state, Roraima is a potential entry route of quarantine pathogens that can threaten Brazilian agriculture. Constant health surveillance is an essential tool to mitigate the risks of the introduction and spread of important pathogens. In order to avoid or reduce the negative impacts caused by diseases resulting from the introduction or occurrence of a pathogen, a well-structured phytosanitary inspection program and technical guidelines for producers are necessary. The combined efforts of research institutions and state agencies aim to reduce production losses caused by diseases. Thus, the objective of this review is to address the main threats and challenges in controlling quarantine pests in the state of Roraima based on the experience of research and extension institutions in monitoring, pest detection and mitigation strategies. In this respect, contextualizing the events discussed may contribute to guiding plant defense measures, thus mitigating the risks of quarantine pathogen introduction and spread in Roraima. -- Resumo: A ocorrência de doenças de plantas em cultivos agrícolas pode impactar negativamente a produção e comercialização de produtos agrícolas de uma região. Roraima, por ser um estado fronteiriço, é vulnerável a ser via de ingresso de patógenos quarentenários que podem ameaçar a agricultura nacional. A constante vigilância sanitária é uma ferramenta essencial para mitigar os riscos de introdução e disseminação de patógenos importantes. Para se evitar ou reduzir os impactos negativos causados por doenças, decorrentes da introdução ou ocorrência de um patógeno, é necessário um programa de defesa fitossanitária bem estruturado e orientações técnicas para os produtores. O trabalho conjunto de instituições de pesquisa e de órgãos de extensão visa reduzir as perdas de produção ocasionadas por doenças. Assim, objetiva-se com essa revisão abordar as principais ameaças e desafios no controle de pragas quarentenárias no estado de Roraima com base na experiência das instituições de pesquisa e de extensão no monitoramento, detecção de pragas e nas ações de mitigação. Dessa forma, a contextualização da sucessão dos eventos abordados poderá contribuir para orientar medidas a serem adotadas em defesa vegetal e, por conseguinte, para mitigação de riscos de introdução e dispersão de patógenos quarentenários em Roraima. Made available in DSpace on 2022-07-26T19:19:51Z (GMT). No. of bitstreams: 1 Halfeld-Vieira-Threats-challenges-2022.pdf: 357280 bytes, checksum: 081f2fd84920d3a0856731d2bb81a7bb (MD5) Previous issue date: 2022

Asian soybean rust (ASR), caused by Phakopsora pachyrhizi, has negatively impacted soybean production worldwide. This study evaluated the effect of foliar spray of acibenzolar-S-methyl (ASM) and jasmonic acid (JA) as well as silicon (Si) supplied, either by soil amendment using calcium silicate or through a nutrient solution, on ASR control as well as on the expression of some defence-related genes (phenylalanine ammonia-lyase (PAL), chitinase (CHI), chalcone isomerase (CHAL), lipoxygenase (LOX), pathogenesis-related protein 1 (PR-1) and metalloproteinase (MET)) in soybean plants infected or not by P. pachyrhizi. Foliar Si concentration ranged from 2.6 to 8.7 dag/kg for Si supply by soil application or through a nutrient solution in comparison with the control treatment (no Si supply). Higher foliar Si concentration contributed to reducing ASR severity greater than 30%, mainly if supplied through nutrient solution. The ASR severity was significantly reduced by 36% with the ASM spray in comparison with the control treatment without any expressive effect on the expression of the analysed genes. The JA spray did not result in reduction on ASR severity in comparison with the control treatment even though with higher transcript levels of PAL at 12 hai. The transcripts levels of MET and PAL were significantly higher for inoculated plants taking up Si from the soil in comparison to non-inoculated plants of this treatment at 72 hai. For Si supply through the nutrient solution (+Si plants), the transcripts levels of LOX and CHAL were significantly higher for inoculated plants in comparison to inoculated -Si ones at 12 hai. At 141 hai, the transcript level of PAL was significantly higher for inoculated + Si plants in comparison to inoculated -Si ones. In conclusion, Si supply contributed decisively to reduce ASR severity through the potentiation of some defence-related genes mainly PAL and CHAL involved, respectively, in the biosynthesis of phenolics and flavonoids. Made available in DSpace on 2020-12-22T09:01:55Z (GMT). No. of bitstreams: 1 Differential-gene-expression.pdf: 849954 bytes, checksum: cce6ffafff730a00ff3a89f4d563fa1b (MD5) Previous issue date: 2020

Essential oils of medicinal plants show potential to control phytopathogens. Essential oils of Lippia sidoides Cham, Lippia lasiocalycina Cham, Lippia origanoides Kunth - Teresina, Lippia origanoides Kunth - Jatobá, Mesosphaerum suaveolens (L.) Kuntze, Croton sonderianus Muell. Arg. And Croton zehntneri Pax et Hoffm. were evaluated regarding their chemical composition and in controlling the Sclerotium rolfsii Sacc. The experiments were carried out in a completely randomized design with five concentrations and the control (without oil application): 0.0313; 0.0625; 0.1250; 0.2500 and 0.500 mL kg-1 in Petri dishes with PDA medium (potato-dextrose-agar). The evaluations consisted of daily measurements of the colony diameter in diametrically opposite directions, 24 h after the experiment installation and maintained until the radial reach of the colony on the edges of the Petri dish, in one of the treatments. The chemical composition of the essential oils were evaluated by GC-MS and the following compounds were identified: Thymol (33.5%, L. sidoides); piperitenone oxide (67.7%, L. lasiocalicyna); borneol (19.2%, L. origanoides); borneol carvacrol (34.4%, L. origanoides ? Jatobá); sabiene (30.3%, M. suaveolens); β-sabinene (30.5%, C. sonderianus); and estragole (90,1%, C. zehntneri). The S. rolfsii fungus is highly sensitive to L. sidoides, L. origanoides - Jatobá and C. zehntneri essential oils, suggesting its use in the management of Sclerotium wilt in cowpea. Made available in DSpace on 2020-06-24T11:11:08Z (GMT). No. of bitstreams: 1 ChemicalCompositionControlSclerotiumAJMR2020.pdf: 865638 bytes, checksum: fbe0cc4672bdf4adede0e1ee1214c7af (MD5) Previous issue date: 2020

The red palm mite, Raoiella indica Hirst (Tenuipalpidae), has mainly been registered on palm species (Arecaceae), and its expansion in Brazil has the potential to cause significant negative impact on cultivated as well as native palms. Here, we evaluate the potential of native palms from Northeast Brazil to act as hosts of R. indica. Specifically, we used in situ free-choice and confinement tests, in which sections of palm leaves/leaflets of various species were experimentally infested with R. indica. We tested the following species: Acrocomia aculeata, Acrocomia intumescens, Allagoptera caudescens, Attalea funifera, Attalea oleifera, Bactris acanthocarpa var. acanthocarpa, Bactris ferruginea, Bactris glassmanii, Bactris hirta var. spruceana, Bactris pickelii, Copernicia prunifera, Desmoncus orthacanthos, Desmoncus polyacanthos, Syagrus coronata and Syagrus schizophylla. All of these were compared with the mite's preferred host, the coconut palm, Cocos nucifera. In the free-choice test, both male and female R. indica preferred C. nucifera in comparison to each of the native palms. In the confinement test, we observed significant differences in the survivorship between mites on native palms and those on coconut palms after the second day of infestation. By the fifth day, survivorship of mites on the native palms was almost always significantly lower than on C. nucifera (excepting for C. prunifera). We conclude that, among all the native palms evaluated, only the carnauba palm (C. prunifera) is at risk from R. indica. This result is relevant as this palm is an economically important species in the region.

Root-knot disease is among the main diseases affecting coffee crop. The plant selection to the development new resistant cultivars is among one the most efficient methods of control. The present work aimed to quantify the resistance responses of Coffea canephora clones to root-knot nematode Meloidogyne incognita in the Western Amazon. For this, 17 previously selected clones were evaluated in three experimental trials, carried out in the municipalities of Ji-Paraná and Porto Velho, Rondônia. The resistance to root-knot nematodes M. incognita were evaluated by the numbers of gall in the roots (NG) and by the reproductive factor (RF). The resistance response was also interpreted according the genetic diversity of the clones based in their morphological traits. The clones BRS3210, C12, BRS2314, BRS3137 and BRS1216 are resistant to M. incognita with RF of 0.34, 0.62, 0.79, 0.86 and 0.98, respectively. BRS3213, C125, C15, BRS2336, BRS3220 and C09 clones were classified as susceptible, with RF of 1.93, 1.95, 2.00, 2.31, 2.32 and 2.35. The BRS3193, C160 and BRS2357 clones were classified as very susceptible, with RF values of 3.03, 4.41 and 5.82, respectively. The clustering based on the genetic diversity of morphological traits indicated that genotypes more similar to the Robusta botanic variety had lower RF. The hybrid plants showed intermediate degrees of resistance indicating the segregation for the character of the M. incognita resistance. The clones BRS3210, C12, BRS2299, BRS2314, BRS3137 and BRS1216 expressed resistance responses to M. incognita with potential for growing resistant genotypes in the Western Amazon. Made available in DSpace on 2020-09-10T04:39:21Z (GMT). No. of bitstreams: 1 ART20076.pdf: 627359 bytes, checksum: 575abca4a6b9678f2ba13c0f95bdfd84 (MD5) Previous issue date: 2020

Recent outbreaks of Verticillium wilt diseases in various vegetable crops have been reported in Brazil. This fact was our initial stimulus to carry out a nationwide survey aiming to determine their causal agent(s). Thus far, Verticillium dahliae has been reported as the predominant species based solely on morphological traits. As other Verticillium species can be associated with wilt diseases, we characterized a collection of 80 isolates, collected across 10 agricultural Brazilian regions, by combining morphological, biological, and molecular traits. A multilocus approach was employed for identification of Verticillium species with information from three genomic regions (ribosomal internal transcribed spacer region, glyceraldehyde-3-phosphate dehydrogenase, and actin genes). Only 21 out of the 80 isolates were unable to produce microsclerotia in culture. The analyses of all genomic regions indicated V. dahliae as the sole species associated with vascular wilt of distinct hosts, including major solanaceous vegetables and other hosts such as trawberry, okra, and cacao. Pathogenicity tests confirmed the infection by the V. dahliae isolates and the development of typical disease symptoms on their original hosts. This is the first nationwide characterization of Verticillium isolates associated with major vegetable crops in Neotropical areas. This provides valuable information to design sound management strategies for these diseases, mainly for establishing efficient rotation systems and for the development of resistant cultivars. Made available in DSpace on 2022-07-10T04:00:32Z (GMT). No. of bitstreams: 1 Plant-Pathology-2022-Suaste8208Dzul-Verticillium-diseases-of-vegetable-crops-in-Brazil-Host-range-microsclerotia.pdf: 2203711 bytes, checksum: 174ffb030b398d1f1c1fc7fd72b1fe7f (MD5) Previous issue date: 2022

Um dos principais problemas no armazenamento de maçãs, se não o principal, é a ocorrência de podridões, tais como mofo azul (Penicillium expansum), mofo cinzento (Botrytis cinerea) e a podridão olho de boi (Neofabraea brasiliensis e N. actinideae). As perdas ocasionadas nesta fase, pelo aparecimento de doenças, resultam em grandes prejuízos econômicos. No Brasil, estima-se que estas perdas ocasionadas pelas podridões pós-colheita em maçãs, durante e após a armazenagem, totalizam 153,73 milhões de reais por ano (OGOSHI etal., 2019).

Especialmente na emergência a podridão radicular de fitóftora é uma ameaça com potencial letal às plantas de soja. Além de lançar mão da resistência genética é importante estar à compactação do solo e ao acúmulo de água, fatores que favorecem a doença e tendem a agravar o problema. Made available in DSpace on 2022-09-02T20:20:00Z (GMT). No. of bitstreams: 1 Art.Cult.Leila.pdf: 7475556 bytes, checksum: 1b87b1c57d1967b40a96ccd7bc2edd65 (MD5) Previous issue date: 2022

Os agentes de controle biológico ou inimigos naturais (predadores, parasitoides e entomopatógenos) são capazes de reduzir populações de artrópodes-praga a níveis inferiores aos de dano econômico, mas sem ocasionar efeitos colaterais indesejáveis ao meio ambiente. Podem ser manejados de forma conservativa, em agroecosistemas estáveis ou criados em laboratórios (biofábricas), para serem liberados, periodicamente, em grandes quantidades em lavouras comerciais (cultivos perenes ou anuais). Defensivos, principalmente os de largo espectro (não seletivos aos inimigos naturais), são a principal tática para o controle de insetos-praga, porém podem causar efeitos deletérios aos inimigos naturais. O problema é potencializado quando empregados sem critérios técnicos, desconsiderando os níveis de controle estabelecidos pela pesquisa para os principais artrópodes-praga das grandes culturas. A tomada de decisão de controle preconizada pelo Manejo Integrado de Pragas (MIP), baseada no limiar de dano econômico e avaliada por meio de monitoramento dos insetospara detecção do nível populacional (nível de controle), indicando a real necessidade de controle, é, muitas vezes, desconsiderada por quem adota práticas mais fáceis de serem empregadas e/ou mais convenientes, a exemplo da aplicação calendarizada de defensivos químicos. A cultura do algodoeiro é reconhecida pelo grande número de insetos associados, e é também alvo de recordes de aplicação de agroquímcos. Isto tem sido motivado, principalmente, pela ocorrência do bicudo do algodoeiro (Anthonomus grandis), além do complexo de lepidópteros-praga (Helicoverpa, Heliothis, Spodoptera etc.), insetos sugadores transmissores de viroses, a exemplo dos afídeos e moscas-brancas, entre outros.

A cenoura é uma hortaliça do grupo das raízes tuberosas, cultivada em larga escala em vários estados brasileiros. Dentre os problemas fitossanitários associados à cultura destacam-se os nematoides galhadores do gênero Meloidogyne, cujas infestações podem acarretar em até 100% de perda da produção. A busca por alternativas ao controle químico tem se intensificado nos últimos anos, com o advento de bionematicidas, especialmente os formulados à base de fungos nematófagos. Assim, o objetivo desse estudo foi comparar a eficiência da aplicação dos fungos Paecilomyces lilacinus e Pochonia chlamydosporia em comparação ao uso do controle químico, em plantio de cenoura sob infestação de nematoide-das-galhas. O estudo foi conduzido no Instituto Taquaritinguense de Ensino Superior (ITES), Taquaritinga, SP, em condições de campo, utilizando a cenoura híbrida var. ?Sirkana?. O delineamento experimental foi em blocos ao acaso (DBC) com cinco repetições e seis tratamentos: 1. P. lilacinus; 2. P. chlamydosporia; 3. P. lilacinus + P. chlamydosporia; 4. Adicarbe; 5. Cadusafós e 6. Testemunha (sem aplicação). As doses dos respectivos tratamentos constaram de 0,67 L/m2 de canteiro com substrato colonizado pelos fungos nematófagos, 30 kg/ha de p.c. de Aldicarbe e 25 kg/ha de p.c. de Cadusafós. Pelos resultados obtidos, os fungos nematófagos P. lilacinus e P. chlamydosporia podem ser recomendados no controle de nematoides-das-galhas em cultivo de cenoura, como alternativa ao controle químico. The carrot is a vegetable of the tuberous roots group, cultivated on a large scale in several Brazilian states. Among the phytosanitary problems associated with the crop, galling nematodes of the genus Meloidogyne stand out, whose infestations can lead to up to 100% loss of production. The search for alternatives to chemical control has intensified in recent years with the advent of bionematicides, especially those formulated based on nematophagous fungi. Thus, the aim of this study was to compare the efficiency of the application of the fungi Paecilomyces lilacinus, and Pochonia chlamydosporia compared to the use of chemical control, in carrot planting under root-knot nematode infestation. The study was carried out at Instituto Taquaritinguense de Ensino Superior (ITES), municipality of Taquaritinga, São Paulo state, Brazil under field conditions, using the hybrid carrot var. 'Sirkana'. The experimental design was in complete randomized blocks with five replications and six treatments: 1. P. lilacinus; 2. P. chlamydosporia; 3. P. lilacinus + P. chlamydosporia; 4. Adicarb; 5. Cadusaphos and 6. Check Treatment (not applicable). The doses of the respective treatments consisted of 0.67 L/m2 of planting bed with substrate colonized by nematophagous fungi, 30 kg/ha of p.c. of Aldicarb, and 25 kg/ha of p.c. of Cadusaphos. Based on the results obtained, the nematophagous fungi P. lilacinus and P. chlamydosporia can be recommended for the control of root-knot nematodes in carrot cultivation, as an alternative to chemical control. Made available in DSpace on 2022-09-16T21:05:19Z (GMT). No. of bitstreams: 1 27363.pdf: 270821 bytes, checksum: 85e38379afcefb1c054c308c3377787b (MD5) Previous issue date: 2022

During 2017/18, 2018/19 and 2019/20 crop seasons, sudden leaf blight symptoms were observed in bulb onion crops in open fields in Santa Catarina State. Eventually, leaves exhibited whitish diamond-shaped spots, characteristic of IYSV-like symptoms. In turn, yellow or light green diamond-shaped spots, which may or may not have a lighter center, were observed on scape from seed onion crop. Made available in DSpace on 2022-02-16T14:02:01Z (GMT). No. of bitstreams: 1 Lima-MF-Summa.pdf: 706229 bytes, checksum: 150be9bed1dc6a0ba94f227c229f58f5 (MD5) Previous issue date: 2021

Made available in DSpace on 2022-04-28T19:41:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-07-01 Background. The necessity of a competent vector for transmission is a primary ecological factor driving the host range expansion of plant arthropod-borne viruses, with vectors playing an essential role in disease emergence. Cassava begomoviruses severely constrain cassava production in Africa. Curiously, begomoviruses have never been reported in cassava in South America, the center of origin for this crop. It has been hypothesized that the absence of a competent vector in cassava is the reason why begomoviruses have not emerged in South America. Methods. We performed a country-wide whitefly diversity study in cassava in Brazil. Adults and/or nymphs of whiteflies were collected from sixty-six cassava fields in the main agroecological zones of the country. A total of 1,385 individuals were genotyped based on mitochondrial cytochrome oxidase I sequences. Results. A high species richness was observed, with five previously described species and two putative new ones. The prevalent species were Tetraleurodes acaciae and Bemisia tuberculata, representing over 75% of the analyzed individuals. Although we detected, for the first time, the presence of Bemisia tabaci Middle East-Asia Minor 1 (BtMEAM1) colonizing cassava in Brazil, it was not prevalent. The species composition varied across regions, with fields in the Northeast region showing a higher diversity. These results expand our knowledge of whitefly diversity in cassava and support the hypothesis that begomovirus epidemics have not occurred in cassava in Brazil due to the absence of competent vector populations. However, they indicate an ongoing adaptation process of BtMEAM1 to cassava, increasing the likelihood of begomovirus emergence in this crop. Dep. de Fitopatologia/BIOAGRO Universidade Federal de Viçosa, MG Dep. de Proteção Vegetal Universidade Estadual Paulista, SP Faculdade de Engenharia Agronômica Universidade Federal do Pará, PA Instituto Federal do Sudeste de Minas Gerais, MG Dep. de Fitotecnia Universidade Federal do Piauí, PI Embrapa Amazônia Oriental, PA Dep. de Fitotecnia e Fitossanidade Universidade Federal do Paraná, PR Centro de Ciências Agroveterinárias Universidade do Estado de Santa Catarina, SC Centro Multidisciplinar do Campus de Barra Universidade Federal do Oeste da Bahia, BA Centro de Ciências Agrárias/Fitossanidade Universidade Federal de Alagoas, AL Embrapa Arroz e Feijão, GO Instituto Capixaba de Pesquisa e Extensão Rural, ES Faculdade de Engenharia Florestal Universidade Federal do Pará, PA Dep. de Proteção Vegetal Universidade Estadual Paulista, SP

RESUMO Sob condições de casa de vegetação foram avaliadas as concentrações de manipueira 25, 50 e 100% e dois períodos de imersão de 9 e 12 h, além da testemunha, no tratamento de rizóforos-semente de inhame naturalmente infectados por Scutellonema bradys e Pratylenchus coffeae. O percentual de brotação dos rizóforos observado aos três meses após o plantio foi de 100% em todos os tratamentos. Aos cinco meses, as concentrações de manipueira nos dois períodos de imersão (25% - 9 horas; 25% e 50% - 12 horas), apresentaram os melhores resultados em relação à testemunha, para as populações finais dos nematoides/g de casca de rizóforos.

Apoharknessia eucalyptorum foi inicialmente descrita em 2017 e identificada em folhas de Eucalyptus dunnii no Sul do Brasil. No entanto, faltam informações sobre o cultivo in-vitro para estudos complementares. No presente estudo folhas de E. dunnii foram inoculadas para demonstrar a patogenicidade de A. eucalyptorum, e o crescimento e esporulação foram avaliados em temperaturas de 15, 20 e 25°C em quatro meios de cultura: extrato de malte-ágar (MEA), batata dextrose-ágar (PDA), suco V8-ágar (V8) e feijão dextrose-ágar (BEAN), sob luz constante. Apoharknessia eucalyptorum causou manchas foliares nas folhas inoculadas. As melhores condições para o crescimento micelial foram em 25°C em PDA, BEAN e MEA. Para a esporulação as melhores condições foram a 25°C em todos os meios testados, e também a 20°C em PDA e BEAN. As características das colônias mudaram com as temperaturas, em 15°C as colônias formaram micélio cotonoso, enquanto que em 25°C o micélio cresceu espalhado pelo meio de cultura formando margens escuras limitadas por micélio branco manchado e conídios. As condições indicadas para o crescimento e esporulação in-vitro de A. eucalyptorum são os meios MEA, PDA e BEAN em 25°C. Made available in DSpace on 2019-10-17T18:17:01Z (GMT). No. of bitstreams: 1 2019AlvaroSPMycelial.pdf: 1957944 bytes, checksum: a318a5b5dd7f8cf41509ecd86cfa5fcf (MD5) Previous issue date: 2019

Wheat blast, caused by the fungus Magnaporthe oryzae Triticum (MoT) pathotype, is one of the most important yield-reducing diseases of wheat, mainly in the tropical wheat-growing regions of South America. In this study, we assessed the effects of nitrogen (N) fertilization on wheat blast epidemics. Factorial experiments were carried out in Londrina (2015 and 2016) and Floresta (two sowings in 2017) with N rates (0, 40, 80 and 120 kg/ha for the first experiment, and 0, 60 and 120 kg/ha for the second) and wheat genotypes (three and six cultivars, for the first and second experiments, respectively) as factors. Wheat blast on spikes occurred only in two out of four experiments: 2015 in Londrina and first sowing of 2017 in Floresta. Nitrogen increased blast severity in the first crop of 2017 in Floresta, where blast severity on spikes ranged from 10 to 94% and yield ranged from 47 to 2823 kg/ha, depending on N rate and genotype. Nitrogen did not affect wheat blast (except for genotype S1) in the 2015 Londrina trial, where blast severity on spikes ranged from 16.9 to 36.8%. Differences in blast severity among genotypes were likely due to different crop heading periods. Our results suggest that N fertilization and sowing time should be considered in a management strategy for reducing the risk of wheat blast epidemics.

RESUMO Ustilago operta, agente causal do carvão, constitui séria ameaça para a produção de sementes de braquiária. O objetivo do presente trabalho foi avaliar a incidência deste patógeno em sementes comerciais de Brachiaria spp. Foram analisados lotes de sementes de cultivares de B. brizantha, B. decumbens, B. humidicola e B. ruziziensis, produzidos em BA, GO, MG, MS, MT e SP, nas safras 20042005 e 2005-2006, e destinados ao comércio interno. Também foi verificada a ocorrência de carvão em alguns lotes de alta pureza, destinados à exportação. Para detecção do patógeno, foram analisadas 400 sementes/lote/safra, em quatro repetições de 100, as quais foram cortadas longitudinalmente e observadas sob lupa para a presença de massa pulverulenta negra, composta por estruturas do fungo. U. operta foi detectado em 32% e 28% dos lotes de sementes de braquiária produzidos em 2004-2005 e 2005-2006, respectivamente. Em 2004-2005, as maiores incidências de carvão nas sementes de ‘Marandu’ foram verificadas nos lotes produzidos em Barreiras, BA (7,3%) e Paraíso, MS (2,3%). Na safra seguinte, lotes de ‘Marandu’ produzidos em Rio Verde, GO, apresentaram a maior porcentagem de sementes com sinais de carvão. Sinais de carvão foram verificados nas sementes de ‘Xaráes’ produzidas em regiões de MG e MS, em ambas as safras (incidência ≤ 1%). Em um lote de ‘Basilisk’ (origem: Paraíso, MS, 2004-2005) constatou-se incidência de carvão nas sementes (1%), constituindo o primeiro registro da interação U. operta B. decumbens. O carvão não foi detectado em sementes de ‘Humidicola’ e ‘Ruziziensis’. A presença de U. operta em lotes de sementes de ‘Marandu’ com alta pureza foi confirmada. ABSTRACT Ustilago operta, causal agent of smut, represents a serious risk to the seed production of brachyaria grass. The objective of this work was to evaluate the incidence of smut in commercial seeds of Brachiaria spp. seeds of cultivars of B. brizantha, B. decumbens, B. humidicola, andB. ruziziensis, destined for the internal market, produced in BA, GO, MG, MS, MT and SP, Brazil, during 2004–2005 and 2005–2006. The occurrence of smut in lots of high purity, destined for the external market, was also analyzed. After a longitudinal cut, 400 seeds/lot/harvest, divided in 4 repetitions of 100, were examined under a stereomicroscope for the presence of a black pulverulent mass, composed of fungal structures. The frequency of U. operta in lots produced in 2004–2005 and 2005–2005 was 32% and 28%, respectively. In the 2004–2005 harvest, the highest incidences of smut in Marandu seeds were observed in lots produced in Barreiras, BA (7.3%) and Paraíso, MS (2.3%). In the next harvest, the highest number of smut-contaminated seeds was detected in lots of Marandu seeds produced in Rio Verde, GO. Smut signals were detected in Xaraés seeds produced in regions of MG and MS (incidence ≤ 1%), in both harvests. In one lot of Basilisk (origin: Paraíso, MS, 2004–2005) there was observed an incidence of smut in seeds (1%). This constitutes the first report of the U. operta – B. decumbens interaction. The smut was not visualized in Humidicola and Ruziziensis seeds. The occurrence of U. operta in lots of high-purity Marandu seeds was confirmed.

The occurrence of diseases is a limiting factor in the development of sorghum crop. Among the diseases that causes losses in sorghum production, anthracnose is the main and most severe, mainly by the genetic variability of the pathogen. In this context, the aim of this study was to evaluate the genetic variability of Colletotrichum sublineolum isolates. DNA were extracted from 56 monosporic isolates of C. sublineolum using a DNA extraction kit, and to perform the analysis of genetic diversity of the isolates were used ISSR primers. After amplification, it was determined the polymorphic information content (PIC), allelic frequency, UPGMA and Tocher clustering analyzes and, using software Structure, the genetic structure. According to the descriptive analysis of the genetic variability of C. Sublineolum isolates, primer AP1 presented the higher value of polymorphic information content (PIC). The higher allelic frequency was observed in loci 06, 09, 10, and 24, and the lowest in locus 02. As for the clustering method, it was observed a tendency of grouping C. sublineolum isolates according the geographic origin and, in addition to demonstrating the genetic variability between the C. sublineolum isolates, it was observed the occurrence of introgression among the isolates. La aparición de enfermedades es un factor limitante en el desarrollo del cultivo de sorgo. Entre las enfermedades que ocasionan pérdidas en la producción de sorgo, la antracnosis es la principal y más grave, principalmente por la variabilidad genética del patógeno. En este contexto, el objetivo de este estudio fue evaluar la variabilidad genética de aislados de Colletotrichum sublineolum. Se extrajo ADN de 56 aislados monospóricos de C. sublineolum utilizando un kit de extracción de ADN, y para realizar el análisis de diversidad genética de los aislados se utilizaron cebadores ISSR. Después de la amplificación, se determinó el contenido de información polimórfica (PIC), la frecuencia alélica, los análisis de agrupamiento de UPGMA y Tocher y, utilizando el software Structure, la estructura genética. Según el análisis descriptivo de la variabilidad genética de los aislados de C. Sublineolum, el cebador AP1 presentó el mayor valor de contenido de información polimórfica (PIC). La mayor frecuencia alélica se observó en los loci 06, 09, 10 y 24, y la menor en el locus 02. En cuanto al método de agrupamiento, se observó una tendencia a agrupar los aislados de C. sublineolum según el origen geográfico y, además de demostrando la variabilidad genética entre los aislados de C. sublineolum, se observó la ocurrencia de introgresión entre los aislados. A ocorrência de doenças é um fator limitante no desenvolvimento da cultura do sorgo. Dentre as doenças que causam prejuízos na produção de sorgo, a antracnose é a principal e mais severa, principalmente pela variabilidade genética do patógeno. Nesse contexto, o objetivo deste estudo foi avaliar a variabilidade genética de isolados de Colletotrichum sublineolum. O DNA foi extraído de 56 isolados monospóricos de C. sublineolum por meio de um kit de extração de DNA, e para realizar a análise da diversidade genética dos isolados foram utilizados os primers ISSR. Após a amplificação, determinou-se o conteúdo de informação polimórfica (PIC), frequência alélica, análises de agrupamento UPGMA e Tocher e, por meio do software Structure, a estrutura genética. De acordo com a análise descritiva da variabilidade genética dos isolados de C. Sublineolum, o primer AP1 apresentou o maior valor de conteúdo de informação polimórfica (PIC). A maior frequência alélica foi observada nos locos 06, 09, 10 e 24, e a menor no locus 02. Quanto ao método de agrupamento, observou-se uma tendência de agrupar os isolados de C. sublineolum de acordo com a origem geográfica e, além de demonstrando a variabilidade genética entre os isolados de C. sublineolum, foi observada a ocorrência de introgressão entre os isolados.

Huanglongbing (HLB) is one of the most devastating diseases for citrus sector. In Brazil, the state of Bahia is free of the disease, however it is on constant alert to prevent its introduction. One of the main areas of citrus exploitation in the state is located in the Recôncavo Baiano?s identity territory and is characterized by family-based production. This study aimed to perform a participative phytosanitary diagnosis with citrus growers from the ?Recôncavo Baiano? region, recording their perception regarding the HLB and its vector, Diaphorina citri. The diagnosis, which featured 109 interviews, was carried out in five prominent cities in citrus production (Cruz das Almas, Governador Mangabeira, Muritiba, Santo Antônio de Jesus and São Felipe). The results showed that 70% of citrus growers never heard of the disease. It also indicated that only 6% of farmers have technical assistance. Even with the tradition of citrus farmers, the use of technologies is still limited. The presented results constitute an important tool for phytosanitary defense, as it provides strategic information that enable the planning of indispensable actions for preventing HLB entry in this territory, and also to minimize its negative impacts, contributing with the maintenance of the citrus production chain. Made available in DSpace on 2021-09-23T13:00:23Z (GMT). No. of bitstreams: 1 Oliveira-et-al-2021-Participatory-survey.pdf: 1305034 bytes, checksum: fa8db35de6e84a898d427bd883db2057 (MD5) Previous issue date: 2021

Lethal yellowing is a disease that causes severe damages to coconut palms and it has devastated the coconut canopy of several Caribbean islands, and areas of southern Florida. The Fiji dwarf coconut accession has demonstrated tolerance to this disease. Pollen storage and germination provides useful information for conservation strategy and genetic improvement programs. The objective of this study was to evaluate pollen viability of Fiji dwarf coconut by in vitro germination under different nutritional and abiotic conditions. For the first experiment, two liquid culture media were evaluated for in vitro germination of Fiji dwarf coconut pollen; the Lora culture medium and the Armendariz culture medium combined with four temperature levels. In the second experiment, different sucrose concentrations in the Lora culture medium (4, 8, 12 and 16%) were evaluated combined with two incubation times (6 and 24 h) in the presence or absence of light. The highest in vitro germination of pollen grain was obtained in Lora culture medium by 24 h incubation period at 28 ºC. The light condition does not influence the germination process. In vitro germination percentage improved as the sucrose concentration increased according to a linear regression. In contrast, damage pollen grain percentage reduced according to a quadratic regression. Made available in DSpace on 2021-12-15T10:47:03Z (GMT). No. of bitstreams: 1 1049.In-vitro-viability.pdf: 2374354 bytes, checksum: 28e84be8c63c79e1b94f98fb779c6b9b (MD5) Previous issue date: 2021

Fusarium wilt, caused by Fusarium oxysporum f. sp. cubense (Foc), is one of the most destructive diseases affecting banana crops worldwide. Therefore, the development of resistant cultivars is a promising alternative to mitigate the effects of the disease on banana plantations. The objectives of this study were to induce somaclonal variation in banana cultivars of the Silk and Cavendish types and to select somaclones resistant to subtropical race 4, thereby enabling the production of fruit in areas where this race is present. Shoot clump apexes of the Grand Naine and Maç ?a (Silk) cultivars were grown in MS medium. The cultures were subcultured four times. They were then challenged with fusaric acid (FA) in an experiment consisting of four treatments with different concentrations (0.1, 0.2, 0.3, and 0.4 mM) and five repetitions, each consisting of a Petri dish containing seven multiple shoot clumps in MS culture medium supplemented with 2.5 mg/L benzylamine purine. Multiple shoot clumps without the addition of FA were also used in the experiment, and were subcultured three times and maintained in a dark room. The multiple shoot clumps that survived the treatment with FA were transferred to MS medium and maintained in the growth chamber in the presence of light. The regenerated plants were later planted in tanks containing soil infested with an isolate classified as Foc subtropical race 4 (Foc STR4), and were evaluated for resistance to the pathogen at 90 days after inoculation (d.a.i.). Pathogen structures were confirmed by root clarification and root staining technique. All somaclones of the Maç ?a (Silk) cultivar were susceptible to Fusarium wilt and two somaclones of the Grand Naine cultivar were selected as resistant. The addition of FA as a selective agent was effective in the selection of somaclones among plants of the Grand Naine cultivar, as shown by the selection of two somaclones resistant to Foc STR4. The next step will consist of the agronomic and market potential validation of the selected somaclones, aiming to confirm their potential use by producers. Made available in DSpace on 2021-09-17T02:17:39Z (GMT). No. of bitstreams: 1 Pre-selection-of-banana.pdf: 13366428 bytes, checksum: b26e9007e667f47036c416fed39c4588 (MD5) Previous issue date: 2021

The main goal of the present work was to elucidate the genetic inheritance of the CPMMV resistance present in BRS Sublime, an Embrapa cultivar with carioca seed type identified as the most promising CPMMV resistance source in Brazil so far. Made available in DSpace on 2021-07-01T18:01:21Z (GMT). No. of bitstreams: 1 BIC-2021-p15-16.pdf: 233028 bytes, checksum: 496e0fbb242bc455445ba1821d32095e (MD5) Previous issue date: 2021

Colour-thresholding digital imaging methods are generally accurate for measuring the percentage of foliar area affected by disease or pests (severity), but they perform poorly when scene illumination and background are not uniform. In this study, six convolutional neural network (CNN) architectures were trained for semantic segmentation in images of individual leaves exhibiting necrotic lesions and/or yellowing, caused by the insect pest coffee leaf miner (CLM), and two fungal diseases: soybean rust (SBR) and wheat tan spot (WTS). All images were manually annotated for three classes: leaf background (B), healthy leaf (H) and injured leaf (I). Precision, recall, and Intersection over Union (IoU) metrics in the test image set were the highest for B, followed by H and I classes, regardless of the architecture. When the pixel-level predictions were used to calculate percent severity, Feature Pyramid Network (FPN), Unet and DeepLabv3+ (Xception) performed the best among the architectures: concordance coefficients were greater than 0.95, 0.96 and 0.98 for CLM, SBR and WTS datasets, respectively, when confronting predictions with the annotated severity. The other three architectures tended to misclassify healthy pixels as injured, leading to overestimation of severity. Results highlight the value of a CNN-based automatic segmentation method to determine the severity on images of foliar diseases obtained under challenging conditions of brightness and background. The accuracy levels of the severity estimated by the FPN, Unet and DeepLabv3 + (Xception) were similar to those obtained by a standard commercial software, which requires adjustment of segmentation parameters and removal of the complex background of the images, tasks that slow down the process. Made available in DSpace on 2021-09-14T13:01:47Z (GMT). No. of bitstreams: 1 AP-Predictive-models-Forests-2021.pdf: 3767412 bytes, checksum: aeaec795a200faae684d5a3ea753e45e (MD5) Previous issue date: 2021

A ferrugem-da-folha (Puccinia triticina Erikss) (Pt) e a ferrugem-do-colmo (Puccinia graminis Pers. f. sp. Tritici Eriks. & E. Henn) (Pgt) representam importantes gargalos à produção de trigo em todo o mundo. Como os patógenos se disseminam e desenvolvem novas virulências, a resistência genética durável é a estratégia mais eficaz de controle. A variedade brasileira ?Toropi‟ mantém resistência durável à Pt por mais de 50 anos, e é considerada um valioso recurso genético para resistência às doenças causadas por ferrugens. Além de ?Toropi‟, a variedade ?BRS 194‟, desenvolvida em 2000, também apresentava resistência a todas as raças de Pt ocorrentes no Brasil e em países da América do Sul, até que sua resistência qualitativa foi superada cinco anos após seu lançamento, pela raça MFP-CT, uma nova virulência de Pt. Este trabalho foi realizado em dois locais (Brasil e Canadá) e teve como objetivo investigar a resistência à ferrugem-da-folha e do colmo de ambas as variedades. Foi desenvolvida uma população duplo-haploide (DH) oriunda de ?Toropi‟ x ?BRS 194‟ e inoculada em fase de plântula com a raça MCJ-HN (Pt) no Brasil. No estágio de planta adulta, a população foi inoculada com MFP-CT (Pt) no Brasil e CCDS (Pt) no Canadá. As linhagens e os parentais também foram genotipados para translocação de centeio 1BL.1RS, em busca de genes de resistência conhecidos presentes neste segmento, e, para o gene Sr36. As plântulas dos genótipos parentais foram inoculadas com os isolados de Pgt: TTKSK (Ug99), TPMK, TMRT, RHTS, MCCF, QTHJF e RTHJ. Os resultados obtidos, para Pt, no estágio de plântula, mostraram resistência para ?BRS 194‟ (TI =; 1) e suscetibilidade para ?Toropi‟ (TI = 3). A proporção de 1:1 do fenótipo encontrado na população DH indicou um único gene de resistência de ?BRS 194‟. No teste de planta adulta no Brasil com MFP-CT, ?BRS 194‟ exibiu suscetibilidade (TI = 3) e ?Toropi‟ apresentou resistência (TI= 0;/0;1). No teste realizado no Canadá com CCDS, ?BRS 194‟ foi suscetível (TI = 3) e ?Toropi‟ resistente (IT = 1-). A variedade ?Toropi‟ revelou não possuir o segmento cromossômico 1BL.1RS, ao contrário de ?BRS 194‟, que mostrou sua presença. ?BRS 194‟ expressou resistência a todas as raças de Pgt, e, para o isolado Ug99 (TTKSK) (TI = 0), foi sugerida a presença do gene Sr36, que foi confirmada pelo marcador STM773-2 (+) e pela variedade ?Arthur 71‟ (portador Sr36) em seu pedigree. A variedade ?Toropi‟ foi resistente a RHTS, MCCF, QTHJF e RTHJ, sugerindo a presença de um gene de resistência a Pgt. Os resultados encontrados geraram novas perspectivas em relação às variedades brasileiras de trigo ?Toropi‟ e ?BRS 194‟. Ambos os genótipos fornecem fontes eficazes de resistência contra Pt e Pgt e são preciosos para a expansão da base genética em programas de melhoramento genético do trigo. Em especial, este trabalho apresenta ?BRS 194‟ como uma variedade adaptada e resistente à Ug99, contribuindo para que os melhoristas estejam à frente na batalha contra este patógeno, ainda não detectado no Brasil. Made available in DSpace on 2021-11-26T02:10:59Z (GMT). No. of bitstreams: 1 Coelho-TS-2021.pdf: 4526306 bytes, checksum: cad3d1cf7a7aad61cdb49a3ab4678b11 (MD5) Previous issue date: 2021 Orientador: Prof. Dra. Nadia Canali Lângaro Coorientador: Dra. Sandra Maria Mansur Scagliusi (CNPT)

he objective of this work was to evaluate the resistance of transgenic papaya populations (PTPs) to Papaya ringspot virus-P (PRSV-P). 'Sunrise Solo' transgenic papaya plants were produced with the gene of the PRSV-P protein coat, and PRSV was mechanically inoculated in plants in greenhouse conditions. The presence of the CP/PRSV gene and homozygosis were evaluated by polymerase chain reaction (PCR). Selected plants and the 'Sunrise Solo' control were transplanted to the field for agronomic evaluations. The plants evaluated in greenhouse conditions showed resistance between 96.3 and 5.8%, without variation of symptoms. The PTPs 1/6, 1/7, 1/9, 1/10, 1/15, 2/38, 2/41, 2/56, 2/65, 3/27, 3/46, 3/48, 4/9, 4/27, 8/4, 8/23, 8/33, 18/3, 18/4, 18/8, 18/22, 18/27, 28/97, 28/104, and 28/110 showed no symptoms, they were ELISA negative, and most of them contained the CP and NPT II genes. PTPs 1/6 and 3/46 had the CP gene in homozygosis and in double insertion. PTPs 1/6/20, 1/6/59, 1/6/64, 1/6/90, 3/46/44, 3/46/52, and 18/27/97 had a well-formed fruit cluster, piriform fruit weighing approximately 500 grams, orange pulp, and less than 10% carpelloidy. PTPs 1/6/59 and 3/46/52 show resistance to PRSV, good agronomic characteristics, and the CP gene in homozygosis. Made available in DSpace on 2021-09-17T02:17:22Z (GMT). No. of bitstreams: 1 Resistance-of-transgenic.pdf: 23626332 bytes, checksum: d7251101e22a1911e338970de2aad36a (MD5) Previous issue date: 2021

A erva-mate (Ilex paraguariensis) é uma espécie florestal de ocorrência natural na região Sul do Brasil, e se destaca pela forte cultura de consumo como chá e chimarrão. O Brasil, mesmo sendo o país com maior área de ervais nativos, é o segundo maior produtor da planta do mundo. Com o aumento do consumo da erva-mate, ocorreu a substituição de ervais nativos por ervais plantados, o que causou maior susceptibilidade às pragas e doenças. O objetivo do presente artigo foi realizar uma revisão sistemática para identificar quais as principais doenças fúngicas que ocorrem na cultura. A busca dos artigos foi realizada nas bases de dados Google Scholar, Periódicos CAPES e Scielo. As palavras-chave utilizadas foram ?doenças erva-mate?, ?fungos erva-mate? e ?Fusarium erva-mate?. No total, foram avaliados 16 artigos, sendo que 7 abordaram a ocorrência de fungos associados a erva-mate, 6 artigos específicos de fungos patogênicos em erva-mate e 3 abordaram métodos de controle de doença em erva-mate. Os artigos também foram classificados em ano de publicação, local de coleta, objetivo do estudo, doença encontrada/avaliada, tipo de amostra e tipo de experimento realizado. O fungo mais frequente foi Fusarium (podridão-de-raízes), que atinge a cultura da erva-mate na região Sul do Brasil. Além disso, também foram abordadas as doenças causadas pelo patógeno Cylindrocladium spathulatum (pinta preta), em artigos mais antigos e Ceratocystis fimbriata (murcha vascular) em um artigo mais recente. Made available in DSpace on 2021-07-04T02:16:58Z (GMT). No. of bitstreams: 1 Celso-Doencas-80320-325346-1-PB.pdf: 297229 bytes, checksum: 5688120e2c69d9ab6a6b851ce62525f7 (MD5) Previous issue date: 2021

A intensidade das doenças e a densidade populacional das pragas variam em função das condições meteorológicas, que afetam tanto patógenos e pragas quanto a sua interação com a planta hospedeira. Para muitas doenças fúngicas, as condições de favorabilidade ao ciclo da doença dependem de um binômio entre temperatura e disponibilidade de água livre.

Resumo ? Objetivou-se neste trabalho avaliar a eficiência de diferentes fungicidas no manejo da brusone em trigo tropical, em Planaltina, DF, nos anos de 2011, 2012, 2014, 2017, 2018 e 2020, quantificando a incidência, a severidade da doença e o rendimento de grãos. Avaliaram-se 16 tratamentos, entre produtos comerciais aplicados isoladamente em diferentes doses ou em misturas, nos 6 anos. Foram observadas diferenças significativas de incidência e severidade da doença em estudo nos anos 2012, 2017, 2018 e 2020. Quanto à produtividade, houve diferenças significativas nos anos de 2011, 2014, 2018 e 2020. A incidência da brusone variou de 4,0% a 100%; a severidade, de 1,9% a 97,8%; e o índice de doença, de 0,08 a 97,8. A principal proposição é a de que a variação nos valores dessas variáveis esteja associada à do clima durante a condução de cada ensaio. Em 2014, 2018 e 2020, a fase de espigamento do trigo coincidiu com um período chuvoso, o que proporcionou altos níveis de incidência e severidade. A produtividade do trigo variou de 15,6 kg ha-1 a 2279 kg ha-1 no sequeiro, enquanto, no sistema irrigado, variou de 4.066 kg ha-1 a 4.754 kg ha-1. A variação de produtividade ocorreu principalmente devido às condições climáticas favoráveis à incidência de brusone nas espigas.

A constatação da importância da canela preta confirma que um dos maiores desafios para o cultivo da batata nos trópicos é a ocorrência das podridões provocadas por bactérias pectolíticas que, se não adequadamente controladas, podem provocar perda total tanto em campo como em pós-colheita.

O uso de genótipos resistentes é um dos principais métodos de controle de doenças no Brasil, sendo fundamental o melhoramento genético visando a obter novos genótipos resistentes, para suprir essa demanda. Assim, o objetivo deste trabalho foi estimar os parâmetros genéticos das variáveis resistência ao cancro, causado por Chrysoporthe cubensis e resistência à mancha foliar, causada por Cylindrocladium spp. e Kirramyces epicoccoides, bem como avaliar suas implicações na estratégia de melhoramento genético de Eucalyptus grandis. Foi instalado um teste de progênies de polinização aberta, em dois locais no Estado de São Paulo, nas regiões de Anhembi e Itatinga. O teste foi realizado em blocos casualizados, com 176 progênies e três testemunhas, uma por parcela, com 30 repetições em Itatinga e 28 repetições na região de Anhembi. A resistência ao cancro foi avaliada aos 12, 24 e 29 meses de idade na região de Anhembi e aos 15, 27 e 32 meses de idade, na região de Itatinga. A resistência à mancha foliar foi avaliada aos 12 e 24 meses de idade na região de Anhembi e aos 15 e 27 meses de idade, na região de Itatinga. Os parâmetros genéticos foram estimados, utilizando o software SELEGEN REML/BLUP®. Com a mesma população de seleção, verificou-se que, para a região de Itatinga, as estimativas de parâmetros genéticos indicam maior potencial para a seleção de genótipos resistentes ao cancro e à mancha foliar. Porém, para as condições edafoclimáticas da região de Anhembi, essa população apresenta potencial de seleção inferior, o que fica evidenciado pelos baixos valores de herdabilidade média individual de progênies estimados. Na região de Itatinga, foram obtidos valores de herdabilidade média individual de progênies para a resistência ao cancro e à mancha foliar, que variaram de moderado a alto, indicando que pode haver bons ganhos com a seleção neste local. Made available in DSpace on 2021-11-17T18:00:24Z (GMT). No. of bitstreams: 1 Celso-Auer-56935-304903-1-PB.pdf: 667287 bytes, checksum: 7bd84f5918fb256edebeb35f07d8643c (MD5) Previous issue date: 2021

É provável que algumas doenças causadas por vírus e viroides acompanham macieiras e outras rosáceas desde os primórdios da sua domesticação pelo homem há milhares de anos. Nestas espécies vegetais exóticas, originárias da Ásia Central, agentes patogênicos coexistiram e coevoluíram provavelmente com os seus hospedeiros, adaptando-se mutuamente. A macieira, como a maioria das fruteiras lenhosas, é plantada sobre porta-enxertos. Na enxertia, uma prática milenar, já conhecida por volta de 3000 anos a.c. o "cavalo" confere à copa características desejáveis como o vigor, adaptação a certos solos, o sistema radicular e a resistência a doenças, entre outras. O filósofo grego Teofrasto, tido como fundador da botânica, três séculos a.c. teria sido autor de um catálogo de espécies de fruteiras compatíveis (enxertáveis) entre si. Vírus e viroides podem ter encontrado na propagação pela enxertia, desde tempos remotos, um eficaz meio para sua transmissão e disseminação, pela ação do homem, além das fronteiras da(s) espécies ancestrais, vindo a infectar novas espécies e cultivares.

The aim of the study was to identify sources of resistance of Passiflora rootstocks to Fusarium sp. in two experimental areas with histories of disease foci in Mato Grosso state, Brazil. The experiment was carried out from June 2012 to December 2015 and was of randomized block design with eight treatments in which susceptible cultivar P. edulis was grafted onto hybrids CPAC MJ-H-87, CPAC MJ-H-76, CPAC MJ-H-86 and CPAC MJ-H-88, the commercial cultivar and native P. edulis, P. nitida and P. alata. Mortality rates of grafted plants were evaluated up to 640 days after transplantation. All Fusarium sp. isolates were identified as F. oxysporum f. sp. passiflorae. Plant mortality occurred earlier in the clay area than in the area with sandy clay loam. Grafted plants involving P. edulis as rootstocks were highly susceptible to Fusarium sp. with overall mortality rates above 56.25% considering both soil types, while plants with CPAC MJ-H-76 or native P. nitida rootstocks were more resistant with mortality rates below 12.5%. Grafted plants with CPAC MJ-H86 as rootstock were highly resistant in clay soil but highly susceptible in soil with high proportion of sand. Only grafted plants involving CPAC MJ-H-76 as rootstock showed moderate resistance. Made available in DSpace on 2021-08-24T02:06:40Z (GMT). No. of bitstreams: 1 2021-cpamt-dsmw-identification-sources-resistance-passiflora-rootstocks-fusariosis-areas-disease-oubreaks-mato-grosso.pdf: 798066 bytes, checksum: 80a1b06a1c302bf803d8a069036f7f0d (MD5) Previous issue date: 2021

A pós-colheita é uma importante etapa na cadeia produtiva de frutas tanto de clima tropical como temperado. As perdas ocasionadas por doenças nesta fase resultam em grandes prejuízos econômicos. As maiores perdas de maçãs armazenadas no Brasil são devido às podridões conhecidas como mofo azul causada por Penicil/ium expansum e a podridão olho de boi associada recentemente à infecção por Neofabraea brasiliensis e N. actinideae (Valdebenito- Sanhueza et al, 2010).

Stenocarpella spp. causes stalk and ear rot in maize and overwinters in stubble during the off-season. Understanding the factors that guide saprophytic colonization is a crucial strategy for management. In this study, we analyzed the abiotic factors and crop management practices in relation to the inoculum of Stenocarpella spp. in stubble by qPCR. Soil samples were used for suppressiveness tests against Fusarium verticillioides, Fusarium graminearum, and Stenocarpella maydis. In the 29 fields, different levels of Stenocarpella spp. were detected. Only three fields were considered suppressive for the three pathogens. Heat maps showed that soil suppressiveness was inversely related to the pathogen concentration, and the suppressiveness of one pathogen was correlated with the suppressiveness of other pathogens. Under no-tillage systems in which rotation with soybeans was adopted, Stenocarpella spp. were detected at lower concentrations than in areas that adopted notillage systems with maize monocultures. While in tillage systems, the maize?maize monocropping increases the inoculum level of Stenocarpella spp. Crop rotation is a factor related to the observed reduction in the pathogen concentration and increases in the broad-spectrum antagonistic microbial communities. These communities guide the suppressiveness of soil-borne diseases in maize fields cultivated under tropical conditions. Made available in DSpace on 2022-06-09T11:19:36Z (GMT). No. of bitstreams: 1 Detection-and-factors-that-induce-Stenocarpella.pdf: 2412534 bytes, checksum: 04c5c7a355f927f6f1bfc594fdd86e8f (MD5) Previous issue date: 2022

Endophytic fungi are capable of infecting plants without inducing the development of any observable symptoms. Certain fungal species can also coexist as latent pathogens in their specific hosts. Several species of Fusarium have been reported to form an association with grasses as endophytes or latent pathogens, some of which are also mycotoxin producers. In this study, we aimed to address whether forage grasses could act as potential reservoirs of species that are pathogenic to maize (Zea mays). To this end, we performed morphological and phylogenetic analyses of the elongation factor 1-α (EF-1α) and the second largest subunit of RNA polymerase II (RPB2) genes and characterized three fungal strains isolated from Panicum maximum (cv. Mombaça) as a new phylogenetic species, Fusarium gigantea, within the Fusarium fujikuroi species complex. Moreover, the results of the pathogenicity test such as the toothpick inoculation assay, revealed that these species caused the stalk rot disease in maize when maintained under greenhouse conditions. This finding highlights P. maximum as a potential reservoir of this pathogen and its role as a threat to maize cultivation. Made available in DSpace on 2021-09-26T02:02:26Z (GMT). No. of bitstreams: 1 Panicum-maximum.pdf: 996965 bytes, checksum: 8c1720f8ade5e2b087f525210423a4db (MD5) Previous issue date: 2021

Delineating species and epidemic lineages in fungal plant pathogens is critical to our understanding of disease emergence and the structure of fungal biodiversity, and also informs international regulatory decisions.Pyricularia oryzae (syn. Magnaporthe oryzae)is a multi-host pathogen that infects multiple grasses and cereals, is responsible for the most damaging rice disease (rice blast), and of growing concern due to the recent introduction of wheat blast to Bangladesh from South America. However, the genetic structure and evolutionary history ofM. oryzae, including the possible existence of cryptic phylogenetic species, remain poorly defined. Here, we use whole-genome sequence information for76 M. oryzaeisolates sampled from 12 grass and cereal genera to infer the population structure ofM. oryzae, and to reassess the species status of wheat-infecting populations of the fungus. Species recognition based on genealogical concordance, using published data or extracting previously-used loci from genome assemblies, failed to confirm a prior assignment of wheat blast isolates to a new species (Pyricularia graminis tritici). Inference of population subdivisions revealed multiple divergent lineages withinM. oryzae, each preferentially associated with one host genus, suggesting incipient speciation following host shift or host range expansion. Analyses of gene flow, taking into account the possibility of incomplete lineage sorting, revealed that genetic exchanges have contributed to the makeup of multiple lineages withinM. oryzae. These findings provide greater understanding of the eco-evolutionary factors that underlie the diversification ofM. oryzaeand highlight the practicality of genomic data for epidemiological surveillance in this important multi-host pathogen.ImportanceInfection of novel hosts is a major route for disease emergence by pathogenic micro-organisms. Understanding the evolutionary history of multi-host pathogens is therefore important to better predict the likely spread and emergence of new diseases.Magnaporthe oryzaeis a multi-host fungus that causes serious cereal diseases, including the devastating rice blast disease, and wheat blast, a cause of growing concern due to its recent spread from South America to Asia. Using whole genome analysis of 76 fungal strains from different hosts, we have documented the divergence ofM. oryzaeinto numerous lineages, each infecting a limited number of host species. Our analyses provide evidence that inter-lineage gene flow has contributed to the genetic makeup of multipleM. oryzaelineages within the same species. Plant health surveillance is therefore warranted to safeguard against disease emergence in regions where multiple lineages of the fungus are in contact with one another.

The severity of plant diseases, traditionally the proportion of the plant tissue exhibiting symptoms, is a key quantitative variable to know for many diseases and is prone to error. Good quality disease severity data should be accurate (close to the true value). Earliest quantification of disease severity was by visual estimates. Sensor-based image analysis including visible spectrum and hyperspectral and multispectral sensors are established technologies that promise to substitute, or complement visual ratings. Indeed, these technologies have measured disease severity accurately under controlled conditions but are yet to demonstrate their full potential for accurate measurement under field conditions. Sensor technology is advancing rapidly, and artificial intelligence may help overcome issues for automating severity measurement under hyper-variable field conditions. The adoption of appropriate scales, training, instruction and aids (standard area diagrams) has contributed to improved accuracy of visual estimates. The apogee of accuracy for visual estimation is likely being approached, and any remaining increases in accuracy are likely to be small. Due to automation and rapidity, sensor-based measurement offers potential advantages compared with visual estimates, but the latter will remain important for years to come. Mobile, automated sensor-based systems will become increasingly common in controlled conditions and, eventually, in the field for measuring plant disease severity for the purpose of research and decision making. Made available in DSpace on 2020-05-12T04:39:44Z (GMT). No. of bitstreams: 1 AP-Phytopathology-Research-2020.pdf: 3687278 bytes, checksum: 1cc4d05c8d98608d3ce2e7d1d2e1b252 (MD5) Previous issue date: 2020 Article 9.

Made available in DSpace on 2020-11-09T09:11:43Z (GMT). No. of bitstreams: 1 Como-manejar.pdf: 6718462 bytes, checksum: 7caf147cc0c6ab1526ba67b84a54accc (MD5) Previous issue date: 2020 Edição especial.

Objetivou-se com este trabalho avaliar a eficiência de sistemas de suporte à tomada de decisão para manejo de requeima e septoriose em tomateiro para mesa e estabelecer Valores de Severidade Diários (VSDs) específicos para cada doença na região de estudo. Made available in DSpace on 2020-08-21T04:12:49Z (GMT). No. of bitstreams: 1 Tese-Mylla4.pdf: 6163799 bytes, checksum: 3042b165360d29d187469da3e370a821 (MD5) Previous issue date: 2020 Tese (Doutorado em Agronomia, área de concentração Produção Vegetal). - Universidade Federal de Goiás, Goiania, 2020. Orientadora: Abadia dos Reis Nascimento; Coorientador: Valdir Lourenço Junior, Embrapa Hortaliças.

BRS 372 and BRS 416 are cotton cultivars with high lint yield and genetic resistance to the main cotton diseases in Brazil, particularly to Ramularia Leaf Spot. They have stable yields, good fiber quality and can contribute to a sustainable cotton disease management in tropical environments. Made available in DSpace on 2020-05-29T04:40:07Z (GMT). No. of bitstreams: 1 BRS372BRS416CottonCultivars2020.pdf: 283939 bytes, checksum: e98366acd1e896a23e9328ba5f8b4d73 (MD5) Previous issue date: 2020 Cultivar release.

O Brasil se destaca por ser o maior produtor mundial de maracujá, com crescimento recente da cultura no Nordeste do Rio Grande do Sul e Sul de Santa Catarina. O Endurecimento dos Frutos do Maracujazeiro (EFM), causado pelo Cowpea aphid- borne mosaic virus (CABMV), é considerada mundialmente a principal doença de etiologia viral e sua identificação em 2016 nestas regiões causou enormes prejuízos aos produtores desta fruta. A principal via de transmissão do CABMV é a inoculação por afídeos vetores através de picadas de prova. Este estudo teve como objetivo identificar as principais espécies de afídeos que ocorrem em pomares de maracujazeiro nos municípios de Santa Rosa do Sul/SC e Torres/RS, através do monitoramento com armadilhas de água do tipo Moericke (amarela) e do tipo Irwin (verde), identificando quais são possíveis transmissoras do CABMV, além de estimar a flutuação na sua abundância, relacionando com dados climáticos da região. Neste trabalho foi verificado também o efeito do uso de óleo vegetal na eficiência de aquisição e transmissão do CABMV por Aphis gossypii em maracujazeiro. O gênero Aphis e a espécie A. gossypii foram os afídeos predominantes nos pomares de maracujazeiro monitorados. A ocorrência de temperaturas médias mensais abaixo de 20°C foram favoráveis a maior dispersão de pulgões alados na região monitorada, e seus picos populacionais ocorreram no final de inverno e início da primavera (agosto a outubro). Foi constatada pela primeira vez a presença do CABMV na espécie Pentalonia nigronervosa. Doses de até 1,0%, de óleo vegetal e mineral não causaram sintomas de fitotoxidez em mudas de maracujá em casa de vegetação. A espécie A. gossypii teve eficiência de 80% na transmissão do CABMV em maracujazeiro em ensaio experimental. A utilização do óleo vegetal causou redução na aquisição e na transmissão do CABMV por A. gossypii em mudas de maracujazeiro em casa de vegetação. A espécie A. gossypii teve eficiência de 80% na transmissão do CABMV em maracujazeiro em ensaio experimental. A utilização do óleo vegetal causou redução na aquisição e na transmissão do CABMV por A. gossypii em mudas de maracujazeiro em casa de vegetação. A utilização de óleos pode se tornar mais uma ferramenta no controle da transmissão do CABMV. Conhecer a flutuação populacional dos afídeos na região poderá auxiliar na adoção de medidas de prevenção e controle do EFM de forma mais precisa. Brazil is the world's largest producer of passion fruit, with recent growth of the crop in the northeast of Rio Grande do Sul and south of Santa Catarina state. The Passionfruit Woodiness Disease (PWD) caused by the Cowpea aphid-borne mosaic virus (CABMV), is considered worldwide the main disease of viral etiology, and its detection in 2016 in these regions has caused a lot of damage to the producers of this fruit. The most important method of transmission of CABMV is inoculation by aphid vectors through trial stings. This study objective to identify the main aphid species occurring in passion fruit orchards in the municipalities of Santa Rosa Sul/SC and Torres/RS, by monitoring with traps water type Moericke (yellow) and the type Irwin (green). The species captured were identified vectors of CABMV, in addition to estimating the population fluctuation of these insects, relating with climatic data from the region. In this work, the effect of using vegetable oil on the efficiency of acquisition and transmission of CABMV by Aphis gossypii in passion fruit was also verified. The Aphis genus and the species A.gossypii were the predominant aphids in the monitored passion fruit orchards. The average monthly temperatures below 20° C favored a greater dispersion of winged aphids in the monitored region, and determination of peaks occurred in late winter and early spring (August to October). CABMV was detected for the first time in the species Pentalonia nigronervosa. Doses of up to 1,0% of vegetable and mineral oil didn ́t cause symptoms of phytotoxicity in passion fruit seedlings in a greenhouse. The species A. gossypii had an efficiency of 80% in the transmission of CABMV in passion fruit in the experiment. The use of vegetable oil caused a reduction in the acquisition and transmission of CABMV by A. gossypii in passion fruit seedlings in a greenhouse. The use of oils may be an alternative of controlling the transmission of CABMV. The knowledge of the population fluctuation of aphids in the region may assist in the adoption of PWD prevention and control measures more precisely.

A ocorrência da mancha preta do amendoim está diretamente relacionada com os elementos climáticos. Desta maneira, a elaboração de mapas de distribuição geográfica e temporal contribui informações sobre o comportamento de patossistemas frente às mudanças climáticas. Assim, o objetivo deste trabalho foi avaliar a evolução da favorabilidade climática à ocorrência da mancha preta para as principais regiões produtoras de amendoim da Argentina e do Brasil em função das mudanças climáticas. Na elaboração dos mapas foram consideradas as principais áreas produtoras de amendoim da Argentina e do Brasil e os meses de janeiro a março. Para a elaboração dos mapas foi empregada a metodologia de análise integrada das projeções climáticas e do problema fitossanitário com suporte do geoprocessamento. Foram considerados o clima normal (1961-1990) e o clima futuro (201-2040, 2041-270 e 2071-2100). Diferentes regras foram adotadas para cada a Argentina e o Brasil, pois elas incorporam as particularidades da doença nas áreas produtoras de cada país, como efeito da interação das características próprias do patógeno virulento, hospedeiro suscetível e ambiente. Os cenários climáticos futuros apontam o aumento da favorabilidade para a ocorrência da mancha preta do amendoim para a Argentina e para o Brasil. Made available in DSpace on 2020-11-11T11:23:37Z (GMT). No. of bitstreams: 1 Evolucao-da-mancha-preta-do-amendoim-nas-principais-regioes-2020.pdf: 1387315 bytes, checksum: 1732127f2cf730d076502b10d472a57c (MD5) Previous issue date: 2020

Este trabalho foi iniciado com o objetivo de determinar o agente etiológico e a caracterização da doença que entre os produtores é conhecida como ?Fogo Mexicano?. Made available in DSpace on 2021-02-12T13:18:28Z (GMT). No. of bitstreams: 1 Vivian-Dissertacao-Fitopatologia-UnB-PDF.pdf: 2053056 bytes, checksum: 79b8148138a95a67087f9575aaf0e6b2 (MD5) Previous issue date: 2020 Dissertação (Mestre em Fitopatologia). Universidade de Brasília, Brasília, DF. Orientado por Alice Kazuko Inoue-Nagata, Embrapa Hortaliças.

Rice blast (Magnaporthe oryzae) limits rice (Oryza sativa) grain yields worldwide. The objective of this investigation was to morphologically, biochemically, and molecularly characterize six bacterial isolates, BRM 32109, BRM 32110, BRM 32111, BRM 32112, BRM 32113, and BRM 32114, and to determine their potential as antagonists to M. oryzae. Morphological characterization was based on colony formation and color, Gram staining, and fluorescent pigment production. Biochemical studies were based on cellulase, chitinase, phosphatase, indoleacetic acid, and siderophore production, as well as biofilm formation. The molecular identification used specific primers for PCR amplification of the 16S rRNA region, followed by sequencing. The antagonism studies involved three experiments, which had randomized designs. Two of them were conducted in laboratory conditions, pairing bacterial colonies and M. oryzae, using bacterial filtrates, and the third was conducted in greenhouse conditions. BRM 32111 and BRM 32112 were identified as Pseudomonas sp., BRM 32113 as Burkholderia sp., BRM 32114 as Serratia sp., and BRM 32110 and BRM 32109 as Bacillus spp. BRM 32112, BRM 32111, and BRM 32113 inhibited the colony of M. oryzae by 68%, 65%, and 48%, respectively. The bacterial suspensions of the BRM 32111, BRM 32112, and BRM 3212 filtrates suppressed leaf blast by 81.0, 79.2, and 66.3%, respectively. BRM 32111 and BRM 32112 were determined to be antagonists of M. oryzae and were found to solubilize phosphate, produce siderophores and cellulose, form biofilms, and suppress leaf blast. These isolates should be further investigated as potential biological control agents for leaf blast control. Made available in DSpace on 2020-11-07T09:15:38Z (GMT). No. of bitstreams: 1 rcaatinga-2020.pdf: 747526 bytes, checksum: bd0d8c5b49b96b0545bd0195853d2d08 (MD5) Previous issue date: 2020

O objetivo deste trabalho foi utilizar a técnica de substituição de copa para tentar reduzir o tempo de avaliação em campo e selecionar clones promissores de cupuaçuzeiro. Árvores de 15 anos de idade no campo tiveram suas copas substituídas e 16 tratamentos (clones) foram utilizados em um delineamento de blocos casualizados com 18 repetições e uma planta por parcela. O experimento durou 10 anos e foram avaliados o número médio de frutos, produção de frutos, sementes e polpa (kg/planta) e os sintomas da doença "vassoura-de-bruxa". Os dados obtidos foram submetidos ao teste de normalidade e, posteriormente, à ANOVA. Os resultados destacaram os clones 32, 42, 44, 46, 47, 61, 62, 63 e 64, reunindo, entre eles, indivíduos com características como produtividade, tolerância à vassoura-de-bruxa e características interessantes de frutos. Os desempenhos demonstram que a técnica foi eficaz na avaliação de genótipos de cupuaçuzeiro, uma vez que os clones revelaram seu potencial, desde os primeiros anos de estabelecimento em campo. Isso permitiu reduzir em pelo menos 30% o tempo necessário para avaliar o genótipo do cupuaçuzeiro. Dos nove clones apresentados, cinco clones (32, 42, 46, 61 e 64) já devem estar disponíveis aos produtores para substituir o dossel de árvores improdutivas. Made available in DSpace on 2020-08-08T11:10:34Z (GMT). No. of bitstreams: 1 0100-2945-rbf-42-4-e-597.pdf: 2092686 bytes, checksum: e1c65db3a7d61864a9946e7e8ad9534b (MD5) Previous issue date: 2020

Made available in DSpace on 2020-04-24T00:44:10Z (GMT). No. of bitstreams: 1 Cultivarabr..pdf: 1366188 bytes, checksum: 33590932bac007119f0f09e9bfbfb188 (MD5) Previous issue date: 2020 Titulo alternativo (revista impressa): Cana: novo cenário.

In Mali, the economy is mainly based on agriculture. Rice contributes about 5% of the GDP and constitutes a strategic sector with enormous potential. Despite its strategic importance, rice cultivation faces multiple biotic constraints among which rice yellow mottle virus disease is the most important one with an incidence varying from 60 to 100%. To reduce yield loses due to this disease, we determined the mode of action of two rice yellow Mottle virus (RYMV) pathotypes previously isolated in rice fields in Mali, and identified by Reverse transcription polymerase chain reaction (RT-PCR). Both types significantly decrease rice height with a more pronounced effect with the type A, which showed more aggressivity even on the SK20-28 genotype recognized as RYMV disease-tolerant variety. Root dry weight, grain production and tiller number were the most affected by the disease. Except for tiller number, the virus type A was always more virulent than the type B. Significant positive correlation was found between disease severity and % reduction in tiller number, percentage reduction in plant height, and grain production. The data presented root inhibition as a mode of action of the two RYMV pathotypes isolated in Mali. This information should be used in order to improve the management strategies for these pathogens on field rice in Mali. Made available in DSpace on 2020-08-27T04:10:26Z (GMT). No. of bitstreams: 1 CNPAF-2020-ajar.pdf: 542909 bytes, checksum: d699de979c76bd44c2608e020e6e4517 (MD5) Previous issue date: 2020 Article number: 71BD88564593.

The banana tree is one of the most cultivated fruit globally; however, some diseases significantly affect its production, such as Fusarium wilt. The most appropriate measure for controlling this disease in areas with inoculum pressure is the use of resistant cultivars. Therefore, this study aimed to generate banana somaclones of the cultivar ?Prata-Anã? resistant to Fusarium wilt by inducing somaclonal variation. ?Prata-Anã? stem apexes were established in vitro in MS culture medium and, on a monthly basis, subcultivated in AIA and adenine sulfate supplemented MS medium with added plant regulators: 6-benzylaminopurine (BAP, 4 ml L-1), Thidiazuron (TDZ, 1 ml L-1), and Paclobutrazol (PBZ, 10 ml L-1). The treatments were: T0: no regulator, T1: BAP, T2: TDZ, T3: PBZ, T4: BAP + TDZ, T5: BAP + PBZ, T6: TDZ + PBZ, and T7: BAP + TDZ + PBZ. After the twelfth subculture, the regenerated plants were planted in boxes containing sterile soil infected with Fusarium oxysporum f. sp. cubense, and evaluated after 90 days for resistance to the pathogen. Somaclonal variants T2-1 and T2-2, generated in Treatment 2, with TDZ, were selected as resistant. This result is promising for the launch of a new Fusarium race 1-resistant banana variety. Made available in DSpace on 2020-12-16T09:02:44Z (GMT). No. of bitstreams: 1 Selection-of-somaclonal-variants-of-the-cultivar-Prata-Ana-1.pdf: 1015035 bytes, checksum: 18994b517b9d7c4fc56492933ccd149c (MD5) Previous issue date: 2020

Resumo: A avaliação de genótipos de feijão guandu como antagônico, resistente ou tolerante ao nematoide das galhas (Meloidogyne enterolobii), pode elevar o potencial multiuso dessa leguminosa e verificar a reação de genótipos a esse fitopatógeno, considerado um dos mais agressivos do gênero, se faz necessário devido à sua ampla disseminação e escassez de controle no território nacional. Assim este trabalho teve por objetivo avaliar a reação de seis genótipos de feijão guandu (Cajanus cajan) ao patógeno M. enterolobii. A avaliação final das plantas ocorreu 80 dias após a inoculação dos fitopatógenos, na qual foram mensuradas variáveis de desenvolvimento das plantas: altura da planta, número de hastes, peso da matéria fresca da raiz e peso da matéria seca. Assim como também variáveis de desenvolvimento do nematoide M. enterolobii: número de galhas, índice de massas de ovos, fator de reprodução e redução do fator de reprodução. A hospedabilidade dos genótipos de feijão guandu foi avaliada por meio de cinco critérios classificatórios de distintos ajuizamentos. Para a produção de forragem, três genótipos foram moderadamente resistentes a M. enterolobii, FGSob/14-09, FGg59-95/14-37 e FG CAM/14-49. No entanto, os genótipos de feijão guandu não se enquadraram como plantas antagonistas, apresentando suscetibilidade ao fitopatógeno. [ Reaction of genotypes of pigeon pea (Cajanus cajan (L.) Millspaugh) to the root-knot nematode (Meloidogyne enterolobii). Abstract: The eEvaluation of genotypes of pigeon pea genotypes as antagonistic, resistant or tolerant to the root-knot nematodes (Meloidogyne enterolobii), may increase the multipurpose potential of this legume, and verifying the reaction of genotypes reaction to this phytopathogen, considered one of the most aggressive pathogens of the genus, isf necessary due to its wide dissemination and scarcity of control in the national territory. Thus, the objective aim of this studywork was to evaluate the reaction of six genotypes of pigeon pea (Cajanus cajan) to the pathogen M. enterolobii. The final evaluation of the plants occurred 80 days after the inoculation of plant phytopathogens, and the following in which plant development variables were measured: plant height, stem number of stems, weight of root fresh root matter weight and weight of dry matter weight. As well as dDevelopmental variables of the nematode M. enterolobii were also evaluated: gall number of galls, egg mass index, reproduction factor and reproduction factor reduction. The host suitability genotypes of pigeon pea genotypes wasere evaluated based ony means of five classification criteria from different trials. For fodder the production of fodder, three genotypes were moderately resistant to M. enterolobii, FG Sob/14-09, FGg59-95/14-37 and FGCAM/14-49. However, the genotypes of pigeon pea did not fit as antagonistic plants, presenting susceptibility to the phytopathogen. Made available in DSpace on 2019-01-24T00:30:31Z (GMT). No. of bitstreams: 1 CNPC2018Reacao.pdf: 256806 bytes, checksum: b2a69f4ba52d8af53ba28127eccb4afd (MD5) Previous issue date: 2019-01-23