Sobre o lugar e a função do fantasma entre os anos de 1953 a 1964 do ensino de Lacan / Sur la place et la fonction du fantôme entre les années 1953 et 1964 dans l'enseignement de Lacan / About the place and function of the phantasm between the years of 1953 to 1964 of Lacan's teaching

O conceito de fantasma possui uma importância crucial para o enquadramento da experiência em psicanálise. Este artigo pretende situar o lugar e a função do fantasma neurótico na experiência analítica partindo da função da fala, tal como proposto por Lacan. Para tanto, selecionamos alguns textos e seminários de Lacan situados entre os anos de 1953 a 1964. Nossa hipótese de trabalho consiste na suposição de que, ao enquadrar uma realidade constituída inconscientemente enquanto resposta ao desejo do Outro, o fantasma serve para perpetuar ao neurótico um senso de ser idêntico a si mesmo à medida em que tende a promover um apagamento de contradições provenientes da posição que, como sujeito, ocupa em relação a este desejo. Ao ser concebida como irrupção de um objeto com valor de não-eu no enquadre fantasmático, a angústia produz um efeito reverso, constituindo, por conseguinte, tanto uma contraprova quanto um apoio na demonstração dessa hipótese.

Le concept de fantôme revêt une importance cruciale pour encadrer l'expérience en psychanalyse. Cet article veut situer la place et la fonction du fantasme névrotique dans l'expérience analytique à partir de la fonction de la parole, comme le propose Lacan. Pour cela, nous avons sélectionné quelques textes et séminaires de Lacan situés entre les années 1953 et 1964. Notre hypothèse de travail est qu'en encadrant une réalité inconsciemment constituée en réponse au désir de l'Autre, le fantôme sert à perpétuer chez le névrosé un sentiment d'être identique à lui-même dans la mesure où il tend à favoriser un effacement des contradictions nées de la position qu'il occupe, en tant que sujet, par rapport à ce désir. Conçue comme l'irruption d'un objet ayant valeur de non-moi dans le cadre fantasmatique, l'angoisse produit un effet inverse, constituant donc à la fois une contre-preuve et un support à la démonstration de cette hypothèse.

The concept of the phantasm holds a crucial importance for framing the experience in psychoanalysis. This article aims to situate the place and function of the neurotic phantasm in the analytical experience, starting from the function of speech as proposed by Lacan. To do so, we have selected some texts and seminars by Lacan between the years of 1953 to 1964. Our working hypothesis is that by framing an unconsciously constituted reality as a response to the Other's desire, the phantasm serves to perpetuate in the neurotic subject a sense of being identical to themselves as it tends to promote an erasure of contradictions arising from the subject's position in relation to this desire. When conceived as the irruption of an object with a non-ego value in the phantasmatic frame, anxiety produces a reverse effect, thereby constituting both a counterproof and a support in demonstrating this hypothesis.

Periradicular and Peri-Implant Lesions Associated with Apical Impact of Osseointegrated Implants in Tooth Roots: Clinical Case Reports

This clinical case report aims to describe the development of periradicular and perimplant cystic lesions resulted from the intimate contact of the apical region of osseointegrated implants of dental roots, and discuss the reasons fo r failure of the guided bone regeneration procedure associated with platelet rich fibrin and leukocytes, this process was used to the treatment of the first case. Case Reports. Three cases were reported, two cases described the close contact between the tooth roots and the osseointegrated implants and another with a distance of 1.08 mm. All cases realized a radiographic, and they had not periapical lesions before contact with the apical region of the osseointegrated implants on the roots of the teeth. In the case with the largest cystic extension, the procedure was: removal of the osseointegrated implant with apicectomy of the neighboring teeth, excisional biopsy of the lesion, and grafting using the technique of guided bone regeneration associated with L-PRF. All three cases, endodontic treatment was performed on the neighboring teeth within 2 years of survival of the osseointegrated implants in order to reverse the existing lesion. Results. The diagnostic hypothesis of the three cases was periradicular and peri-implant lesion, arising from a contact of the apical region of the osseointegrated implant with the adja cent tooth. The distance of 1.08 mm between the apices did not ensure normality of the periradicular and peri-implant tissues. The intimate contact caused lesions of different extents and root fractures. Conclusion. Premature contact of the osseointegrated implant with the root region of the neighboring tooth may lead to the development of periradicular and peri-implant lesions, suggesting that it is not possible to control this infectious process with endodontic treatment of the injured tooth.

Este reporte de caso clínico tuvo como objetivo describir el desarrollo de lesiones quísticas perirradiculares y periimplantarias resultantes del contacto íntimo de la región apical de implantes osteointegrados de raíces dentales, y además discutir las razones del fracaso del procedimiento de regeneración ósea guiada asociado a fibrina rica en plaquetas y leucocitos. Este proceso se utilizó para el tratamiento del primer caso. Se reportaron tres casos, en dos casos se describieron el estrecho contacto entre las raíces de los dientes y los implantes osteointegrados y en el otro se determinó una distancia de 1,08 mm. En los tres casos se realizó una radiografía y se determinó que no existían lesiones periapicales, antes del contacto con la región apical de los implantes osteointegrados, en las raíces de los dientes. En el caso de mayor extensión quística, el procedimiento fue: extracción del implante osteointegrado con apicectomía de los dientes vecinos, biopsia excisional de la lesión e injerto mediante la técnica de regeneración ósea guiada asociada a L-PRF. En los tres casos, el tratamiento de endodoncia se realizó en los dientes vecinos dentro de los 2 años de supervivencia de los implantes osteointegrados para revertir la lesión existente. La hipótesis diagnóstica de los tres casos fue lesión perirradicular y periimplantaria, originada por un contacto de la región apical del implante osteointegrado con el diente adyacente. La distancia de 1,08 mm entre los ápices no aseguraba la normalidad de los tejidos perirradiculares y periimplantarios. El contacto íntimo provocó lesiones de diferente extensión y fracturas radiculares. El contacto prematuro del implante osteointegrado con la región radicular del diente vecino puede conducir al desarrollo de lesiones perirradiculares y periimplantarias, lo que sugiere que no es posible controlar este proceso infeccioso con tratamiento endodóntico del diente lesionado.

Introgression of bacterial leaf blight (BLB) resistant gene, Xa7 into MARDI elite variety, MR219 by marker assisted backcrossing (MABC) approach / Introdução do gene resistente à ferragem da folha bacteriana (BLB), xa7 na variedade MARDI elite, MR219 por abordagem de backcrossing assistida por marcador (MABC)

Abstract Bacterial leaf blight (BLB) is one of the major rice diseases in Malaysia. This disease causes substantial yield loss as high as 70%. Development of rice varieties which inherited BLB resistant traits is a crucial approach to promote and sustain rice industry in Malaysia. Hence, this study aims were to enhance BLB disease resistant characters of high yielding commercial variety MR219 through backcross breeding approach with supporting tool of marker-assisted selection (MAS). Broad spectrum BLB resistance gene, Xa7 from donor parent IRBB7 were introgressed into the susceptible MR219 (recurrent parent) using two flanking markers ID7 and ID15. At BC3F4, we managed to generate 19 introgressed lines with homozygous Xa7 gene and showed resistant characteristics as donor parent when it was challenged with Xanthomonas oryzae pv. oryzae through artificial inoculation. Recurrent parent MR219 and control variety, MR263 were found to be severely infected by the disease. The improved lines exhibited similar morphological and yield performance characters as to the elite variety, MR219. Two lines, PB-2-107 and PB-2-34 were chosen to be potential lines because of their outstanding performances compared to parent, MR219. This study demonstrates a success story of MAS application in development of improved disease resistance lines of rice against BLB disease.

Resumo A mancha bacteriana das folhas (BLB) é uma das principais doenças do arroz na Malásia. Essa doença causa perdas substanciais de rendimento de até 70%. O desenvolvimento de variedades de arroz que herdaram características de resistência ao BLB é uma abordagem crucial para promover e sustentar a indústria do arroz na Malásia. Portanto, o objetivo deste estudo foi aumentar os caracteres BLB resistentes a doenças da variedade comercial MR219 de alto rendimento por meio de uma abordagem de cruzamento retrocruzamento com ferramenta de apoio de seleção assistida por marcador (MAS). O gene de resistência a BLB de amplo espectro, Xa7 do pai doador IRBB7, foi introgressado no MR219 suscetível (pai recorrente) usando dois marcadores flanqueadores ID7 e ID15. No BC3F4, conseguimos gerar 19 linhagens introgressadas com o gene Xa7 homozigoto e apresentamos características de resistência como genitor doador quando desafiado com Xanthomonas oryzae pv. oryzae por inoculação artificial. O pai recorrente MR219 e a variedade controle, MR263, estavam gravemente infectados pela doença. As linhas melhoradas exibiram características morfológicas e de desempenho de rendimento semelhantes às da variedade elite, MR219. Duas linhas, PB-2-107 e PB-2-34, foram escolhidas como linhas potenciais por causa de seus desempenhos excelentes em comparação com a mãe, MR219. Este estudo demonstra uma história de sucesso de aplicação de MAS no desenvolvimento de linhas de arroz melhoradas com resistência a doenças contra a doença BLB.

Ameliorative effects of Lactobacillus against Aflatoxin B1 / Efeitos benéficos do Lactobacillus contra a Aflatoxin B1

Abstract Lactobacilli are probiotics with Aflatoxin (AF) detoxification ability, found in fermented products, GIT of animals and environment. Purpose of this study was to investigate the ability of broiler isolates of Lactobacillus against Aflatoxin B1 (AFB1). For this purpose, 5 isolates of Lactobacillus from broiler gut were incubated with 100 ppb AFB1 in aqueous environment and effect of different parameters (cell fractions, time, temperature, pH) on detoxification was determined by HPLC. The ameliorative effect of Lactobacillus salivarius (LS) against AFB1 was studied in broiler. The results revealed that LS (CR. 4) showed the best results (in vitro) as compared to other isolates (L. salivarius (CR. 3, CR, 4), L. agilis (CE. 2.1, CE. 3.1) and L. crispatus (CE. 28). Cell debris of CR. 4 showed significantly higher detoxification (P<0.05). Maximum amount of AFB1 was detoxified at 30°C (97%), pH 4.0 (99%) and 6 h (99.97%). In vivo study showed that AFB1 decreased weight gain (1,269 ± 0.04 gm/ bird), feed consumed (2,161 ± 0.08 gm/ bird), serum total protein (2.42 ± 0.34 gm/ dl), serum albumin (0.5 ± 0.2 2 gm/dl) and antibody titer (4.2 ± 0.83). Liver function enzymes were found (alanine transaminase (ALT): 32 ± 10.7 U/L) and aspartate transaminase (AST): 314.8 ± 27 U/L) elevated in AFB1 fed broilers. Treatment with 1% LS not only decreased the toxic effects of AFB1 (group D) but also improved the overall health of broilers due to its probiotic effects (p<0.05) as compared to control negative (group A). The detoxification ability of LS was better than commercial binder (CB) (0.2% Protmyc). It was concluded that detoxification of AFB1 by Lactobacillus was strain, temperature, pH and time dependent. LS has detoxification ability against AFB1 in vivo.

Resumo Os lactobacilos são probióticos com capacidade de desintoxicação da Aflatoxina (AF), encontrados em produtos fermentados, TGI de animais e meio ambiente. O objetivo deste estudo foi investigar a capacidade de isolados de frango de corte de Lactobacillus contra a Aflatoxina B1 (AFB1). Para tanto, 5 isolados de Lactobacillus de intestino de frango foram incubados com 100 ppb AFB1 em meio aquoso, e o efeito de diferentes parâmetros (frações celulares, tempo, temperatura, pH) na desintoxicação foi determinado por CLAE. O efeito melhorador de Lactobacillus salivarius (LS) contra AFB1 foi estudado em frangos de corte. Os resultados revelaram que LS (CR. 4) apresentou os melhores resultados (in vitro) em comparação com outros isolados [L. salivarius (CR. 3, CR. 4), L. agilis (CE. 2.1, CE. 3.1) e L. crispatus (CE. 28)]. Detritos celulares de CR. 4 mostraram desintoxicação significativamente maior (P < 0.05). A quantidade máxima de AFB1 foi desintoxicada a 30 °C (97%), pH 4.0 (99%) e 6 h (99,97%). O estudo in vivo mostrou que AFB1 diminuiu o ganho de peso (1,269 ± 0.04 g / ave), alimento consumido (2,161 ± 0.08 g / ave), proteína total sérica (2.42 ± 0.34 g / dl), albumina sérica (0.5 ± 0.22 gm / dl) e título de anticorpo (4.2 ± 0.83). As enzimas da função hepática foram encontradas (alanina transaminase (ALT): 32 ± 10.7 U / L) e aspartato transaminase (AST): 314.8 ± 27 U / L) elevadas em AFB1 alimentados com frangos. O tratamento com 1% LS não só diminuiu os efeitos tóxicos de AFB1 (grupo D), mas também melhorou a saúde geral dos frangos devido aos seus efeitos probióticos (p < 0.05) em comparação com o controle negativo (grupo A). A capacidade de desintoxicação do LS foi melhor do que o aglutinante comercial (CB) (0.2% Protmyc). Concluiu-se que a desintoxicação de AFB1 por Lactobacillus foi dependente da cepa, temperatura, pH e tempo. LS tem capacidade de desintoxicação contra AFB1 in vivo.

Combining ability analysis in bitter gourd (Momordica charantia L. ) for potential quality improvement / Análise de capacidade de combinação em cabaça-amarga (Momordica charantia L. ) para melhoria potencial da qualidade

Abstract Combining ability analysis provides useful information for the selection of parents, also information regarding the nature and magnitude of involved gene actions. Crops improvement involves strategies for enhancing yield potentiality and quality components. Targeting the improvement of respective characters in bitter gourd, combining ability and genetic parameters for 19 characters were estimated from a 6×6 full diallel analysis technique. The results revealed that the variances due to general combining ability (GCA) and specific combining ability (SCA) were highly significant for most of the important characters. It indicated the importance of both additive and non-additive gene actions. GCA variances were higher in magnitude than SCA variances for all the characters studied indicating the predominance of the additive gene effects in their inheritance. The parent P2 (BG 009) appeared as the best general combiner for earliness; P1 (BG 006) for number of fruits, average single fruit weight and fruit yield; P4 (BG 027) for node number of first female flower and days to seed fruit maturity; P3 (BG 011) for fruit length and thickness of the fruit flesh; P5 (BG 033) for 100-seed weight; and P6 for number of nodes per main vine. The SCA effect as well as reciprocal effect was also significant for most of the important characters in different crosses.

Resumo A análise da capacidade de combinação fornece informações úteis para a seleção dos pais, também informações sobre a natureza e a magnitude das ações dos genes envolvidos. A melhoria das safras envolve estratégias para aumentar a potencialidade da produção e os componentes de qualidade. Visando ao aprimoramento dos respectivos caracteres em cabaça-amarga, capacidade de combinação e parâmetros genéticos para 19 caracteres, foram estimados a partir de uma técnica de análise dialélica completa 6 × 6. Os resultados revelaram que as variâncias, devido à capacidade geral de combinação (GCA) e capacidade específica de combinação (SCA), foram altamente significativas para a maioria dos caracteres importantes. Indicou a importância das ações gênicas aditivas e não aditivas. As variâncias GCA foram maiores em magnitude do que as variâncias SCA para todos os caracteres estudados, indicando a predominância dos efeitos do gene aditivo em sua herança. O pai P2 (BG 009) apareceu como o melhor combinador geral para o início; P1 (BG 006) para número de frutos, peso médio de um único fruto e produção de frutos; P4 (BG 027) para número de nó da primeira flor fêmea e dias para a maturidade do fruto da semente; P3 (BG 011) para comprimento do fruto e espessura da polpa do fruto; P5 (BG 033) para peso de 100 sementes; e P6 para o número de nós por videira principal. O efeito SCA, bem como o efeito recíproco, também foi significativo para a maioria dos personagens importantes em cruzamentos diferentes.

Exogenous application of salicylic acid induces salinity tolerance in eggplant seedlings / Aplicação exógena de ácido salicílico induz tolerância à salinidade em mudas de berinjela

Abstract Under salt stress conditions, plant growth is reduced due to osmotic, nutritional and oxidative imbalance. However, salicylic acid acts in the mitigation of this abiotic stress by promoting an increase in growth, photosynthesis, nitrogen metabolism, synthesis of osmoregulators and antioxidant enzymes. In this context, the objective was to evaluate the effect of salicylic acid doses on the growth and physiological changes of eggplant seedlings under salt stress. The experiment was conducted in a greenhouse, where the treatments were distributed in randomized blocks using a central composite matrix Box with five levels of electrical conductivity of irrigation water (CEw) (0.50; 1.08; 2.50; 3.92 and 4.50 dS m-1), associated with five doses of salicylic acid (SA) (0.00; 0.22; 0.75; 1.28 and 1.50 mM), with four repetitions and each plot composed of three plants. At 40 days after sowing, plant height, stem diameter, number of leaves, leaf area, electrolyte leakage, relative water content, and total dry mass were determined. ECw and SA application influenced the growth and physiological changes of eggplant seedlings. Increasing the ECw reduced growth in the absence of SA. Membrane damage with the use of SA remained stable up to 3.9 dS m-1 of ECw. The relative water content independent of the CEw increased with 1.0 mM of SA. The use of SA at the concentration of 1.0 mM mitigated the deleterious effect of salinity on seedling growth up to 2.50 dS m-1 of ECw.

Resumo Em condições de estresse salino, o crescimento das plantas é reduzido, em virtude, do desequilíbrio osmótico, nutricional e oxidativo. Contudo, o ácido salicílico atua na mitigação desse estresse abiótico por promover incremento no crescimento, fotossíntese, metabolismo do nitrogênio, síntese de osmorreguladores e enzimas antioxidantes. Nesse contexto, objetivou-se avaliar o efeito de doses de ácido salicílico sobre o crescimento e alterações fisiológicas de mudas de berinjela sob estresse salino. O experimento foi conduzido em casa de vegetação, onde os tratamentos foram distribuídos em blocos ao acaso utilizando uma matriz composta central Box com cinco níveis de condutividade elétrica da água de irrigação (CEa) (0,50; 1,08; 2,50; 3,92 e 4,50 dS m-1), associada a cinco doses de ácido salicílico (AS) (0,00; 0,22; 0,75; 1,28 e 1,50 mM), com quatro repetições e cada parcela composta por três plantas. Aos 40 dias após a semeadura, foram determinados a altura da planta, diâmetro do caule, número de folhas, área foliar, vazamento de eletrólito, teor relativo de água e massa seca total. A CEa e a aplicação de AS influenciaram no crescimento e nas alterações fisiológicas das mudas de berinjela. O aumento da CEa reduziu o crescimento na ausência de AS. O dano de membrana com o uso de AS manteve-se estável até 3,9 dS m-1 de CEa. O conteúdo relativo de água independentemente da CEa aumentou com 1 mM de SA. O uso de AS na concentração de 1 mM mitigou o efeito deletério da salinidade no crescimento das mudas até 2,50 dS m-1 de CEa.

Effects of Se nanoparticles supplementation on growth performance, hematological parameters and nutrient digestibility of Labeo rohita fingerling fed sunflower meal based diet / Efeitos da suplementação de nanopartículas de Se no desempenho de crescimento, parâmetros hematológicos e digestibilidade de nutrientes da dieta baseada em farinha de girassol alimentada com alevinos de Labeo rohita

Abstract The aim of the present study is to assess the effects of selenium nanoparticles on the growth, hematology and nutrients digestibility of Labeorohita fingerlings. Fingerlings were fed with seven isocaloric sunflower meal-based diet supplemented with different concentrations of nanoparticles naming T1 to T7 (0, 0.5, 1, 1.5, 2, 2.5, and 3 mg/kg), with 5% wet body weight while chromic oxide was used as an indigestible marker. After experimentation for 90 days T3 treated group (1mg/kg -1Se-nano level) showed the best result in hematological parameters (WBC's 7.97 ×103mm-3, RBC's 2.98 ×106 mm-3 and Platelet count 67), nutrient digestibility (crude protein: 74%, ether extract: 76%, gross energy: 70%) and growth performance (weight gain 13.24 g, weight gain% 198, feed conversion ratio 1.5, survival rate 100%) as compared to the other treatment groups. Specific growth rates were found significantly higher in T5 than in other groups. The present study indicated positive effect of 1 mg/kg Se-nanoparticles on growth advancement, hematological parameters, and nutrients digestibility of L. rohita fingerlings.

Resumo O objetivo do presente estudo é avaliar os efeitos das nanopartículas de selênio no crescimento, hematologia e digestibilidade dos nutrientes de alevinos de Labeo rohita. Os alevinos foram alimentados com sete dietas isocalóricas à base de farinha de girassol suplementada com diferentes concentrações de nanopartículas, nomeando T1 a T7 (0, 0,5, 1, 1,5, 2, 2,5 e 3 mg / kg), com 5% do peso corporal úmido enquanto o óxido crômico foi usado como um marcador indigesto. Após a experimentação por 90 dias, o grupo tratado com T3 (nível 1mg / kg -1Se-nano) mostrou o melhor resultado em parâmetros hematológicos (WBC's 7,97 × 103mm-3, RBC's 2,98 × 106mm-3 e contagem de plaquetas 67), digestibilidade dos nutrientes (proteína bruta: 74%, extrato de éter: 76%, energia bruta: 70%) e desempenho de crescimento (ganho de peso 13,24 g, ganho de peso % 198, taxa de conversão alimentar 1,5, taxa de sobrevivência 100%) em comparação com os outros grupos de tratamento. As taxas de crescimento específicas foram encontradas significativamente mais altas em T5 do que em outros grupos. O presente estudo indicou efeito positivo de 1 mg / kg de nanopartículas de Se no avanço do crescimento, parâmetros hematológicos e digestibilidade de nutrientes de alevinos de L. rohita.

Pre-germination treatments of melon seeds for the production of seedlings irrigated with biosaline water / Tratamentos pré-germinativos de sementes de melão para a produção de mudas irrigadas com água biossalina

Abstract Melon production in the Brazilian semi-arid region is subject to the use of marginal waters with high salinity. However, the use of regulators and bioactivators in seed treatment can mitigate the harmful effects of salts in irrigation water. In this context, the objective was to evaluate the effect of pre-germination treatments with plant regulators and bioactivator in melon seeds for the production of seedlings irrigated with biosaline water from fish farming effluent. For this, two trials with the Goldex and Grand Prix hybrids were carried out separately. A completely randomized design was used in a 4 × 3 factorial scheme (pre-germination treatments × water dilutions). In addition to the control, the seeds were treated with salicylic and gibberellic acids and thiamethoxam. The waters used for irrigation were local-supply water, fish farming effluent (biosaline water) and these diluted to 50%. Physiological and biochemical analyses were performed for fourteen days. Biosaline water (5.0 dS m-1) did not affect the emergence of Goldex melon seedlings, but compromised the establishment of the Grand Prix cultivar. Seed pre-treatments with salicylic and gibberellic acids attenuate the effects of water salinity and promote growth modulations, resulting in more vigorous melon seedlings.

Resumo A produção de meloeiro no semiárido brasileiro está sujeita a utilização de águas marginais com salinidade elevada. Entretanto, a utilização de reguladores e bioativadores no tratamento de sementes podem mitigar os efeitos nocivos dos sais na água de irrigação. Nesse sentido, objetivou-se avaliar o efeito de tratamentos pré-germinativos com fitorreguladores e bioativador em sementes de melão para a produção de mudas irrigadas com água biossalina de efluente de piscicultura. Para isso, dois ensaios com os híbridos Goldex e Grand Prix foram realizados separadamente. Utilizou-se delineamento inteiramente casualizado em esquema fatorial 4 × 3 (tratamentos pré-germinativos × diluições de água). Além do controle, as sementes foram tratadas com os ácidos salicílico e giberélico, e tiametoxam. As águas utilizadas para irrigação foram a de abastecimento local, efluente de piscicultura (água biossalina) e estas diluídas a 50%. Durante quatorze dias foram realizadas as análises fisiológicas e bioquímicas. A água biossalina (5,0 dS m-1) não afetou a emergência de plântulas de meloeiro Goldex, mas prejudicou o estabelecimento da cultivar Grand Prix. Os pré-tratamentos de sementes com os ácidos salicílico e giberélico atenuam os efeitos da salinidade da água e promovem modulações no crescimento, proporcionando mudas de meloeiro mais vigorosas.

Characterization of the Bipolaris maydis: symptoms and pathogenicity in popcorn genotypes (Zea mays L. ) / Caracterização de Bipolaris maydis: sintomas e patogenicidade em genótipos de milho-pipoca (Zea mays L. )

Southern corn leaf blight (SCLB) is one of the most important corn leaf diseases. Appropriate management strategies and the use of resistant cultivars allow disease control. Therefore, knowing the aspects related to the pathogen and the response of hosts makes it possible to design efficient strategies for selecting genotypes resistant to this disease. In this sense, the objective was to carry out the Bipolaris maydis isolate characterization, evaluating the pathogenicity in different popcorn lines and the symptoms generated in the host after inoculation. The isolate characterization consisted of the macromorphological evaluation of the colonies and the micromorphological evaluation of the conidia in the PDA medium. An experiment was carried out in a greenhouse to evaluate the pathogenicity of the isolate, using 20 inbred lines of popcorn in a randomized block design with four replicates. Inoculation was carried out by spraying leaves, with a suspension containing 1.0 x 104 conidia.ml-1 of the CF/UENF 501 isolate of B. maydis. An incidence assessment and three assessments of disease symptom severity were performed, with seven days intervals between evaluations. The morphological characterization data of the isolate were analyzed using descriptive statistics, and for disease severity, the linear regression model was applied the first-degree model. The variance analysis was performed for the linear and angular coefficients obtained for each treatment. When a difference was found, the Scott-Knott clustering algorithm at 5% significance was applied. The isolate had gray-green colonies, a cottony appearance, and an irregular shape. The lines L353, L354, and L624 show more resistance at the beginning and throughout the evaluations. The high virulence of the CF/UENF 501 isolate made it possible to differentiate the lines in terms of disease intensity and the pattern of symptoms presented.

Mancha-de-Bipolaris é uma das mais importantes doenças foliares do milho. Estratégias de manejo adequadas e o uso de cultivar resistente permitem o controle da doença, mas para tanto, conhecer os aspectos associados ao patógeno e a resposta do hospedeiro é necessário para traçar estratégias eficientes para seleção de genótipos resistentes a essa doença. Neste sentido, objetivou-se realizar a caracterização do isolado de Bipolaris maydis avaliando a patogenicidade em diferentes linhagens de milho-pipoca e os sintomas gerados no hospedeiro a partir da inoculação. A caracterização do isolado consistiu na avaliação macromorfológica das colônias e micromofológica dos conídios em meio nutritivo BDA. Para avaliação da patogenicidade do isolado foi conduzido um experimento em casa de vegetação utilizando 20 linhagens endogâmicas de milho-pipoca, com delineamento em blocos casualizados, com quatro repetições. A inoculação foi realizada por meio de pulverização em folhas, com uma suspensão contendo 1,0 x 104 conídios.ml-1 do isolado CF/UENF 501 de B. maydis. Foi realizada uma avaliação de incidência e três avaliações de severidade dos sintomas da doença, com o intervalo de sete dias para cada avaliação. Os dados da caracterização morfológica do isolado foram analisados por meio da estatística descritiva e para severidade da doença foi aplicado o modelo de regressão linear de primeiro grau. Realizou-se a análise de variância para o coeficiente linear e angular obtido para cada tratamento e quando constatada diferença aplicou-se o agrupamento de médias de Scott-knott a 5% de significância. O isolado apresentou colônias com coloração cinza esverdeado, aspecto algodonoso e forma irregular. As linhagens L353 e L354 e L624 estão entre as linhagens que apresentaram maior resistência no inicio e ao longo das avaliações. A elevada virulência do isolado CF/UENF 501 possibilitou diferenciar as linhagens quanto a intensidade da doença, bem como o padrão dos sintomas apresentados.

Effect of microparticles derived from bone marrow mesenchymal stem cells on cardiomyocyte hypertrophy and its mechanism / 中国生物制品学杂志

@#Objective To investigate the effect of microparticles(MPs)derived from bone marrow mesenchymal stem cells(BMSCs) on myocardial hypertrophy and its mechanism.Methods The osteogenic differentiation and adipogenic differentiation of mesenchymal stem cells(MSCs) were induced. After isolation and purification,the morphological characteristics were observed by transmission electron microscope,and the MPs surface antigen was identified by flow cytometry. Myocardial hypertrophy model was induced by using isoprenaline(ISO)in rats,which were measured for the cardiac structure and function by echocardiography,and then detected for various indexes of the heart and isolated left ventricle. Single ventricular myocytes of rats were acutely isolated and divided into control group(Control group),cardiomyocyte hypertrophy group(ISO group),MPs group(MPs group),and MPs supernatant group(Supernatant group). The mRNA expressions of atrial natriuretic peptide(ANP)and B-type natriuretic peptide(BNP)were detected by qRTPCR. The expression levels of calmodulin-dependent protein kinaseⅡ（CaMKⅡ）and phosphorylated calmodulin-dependent protein kinaseⅡ（p-CaMKⅡ）were detected by ELISA. The L-type calcium current(LCa-L)in single ventricular myocyte of various groups was recorded by whole-cell patch clamp.Results The bone nodules of MSCs osteogenic differentiation turned red after alizarin red staining,and lipid droplets of adipogenic differentiation turned red after oil red O staining;Under transmission electron microscope,MPs membrane had a complete structure,a clear outline and a diameter of about200 nm;The positive rates of CD29 and CD90 on the surface of MPs were(98. 24 ± 0. 82)% and(97. 69 ± 1. 83)%,respectively. Compared with Control group,the left ventricular end diastolic dimension(LVEDD)reduced signifi-cantly(t =5. 065,P < 0. 05),while the interventricular septum end-diastolic dimension(IVSd),left ventricular posterior wall dimension(LVPWd),heart weight to body weight ratio(HW/BW),and heart weight to tibial length ratio(HW/Tibia)significantly increased in ISO group(t = 4. 013,2. 368,4. 392,5. 043 and 6. 120,respectively,each P < 0. 05),indicating that the hypertrophic model was successfully established. The expression levels of ANP and BNP mRNA in hypertrophic cardiomyocytes of rats in ISO group were significantly higher than those in Control group(t = 25. 120 and18. 261,respectively,each P < 0. 01);While the expression levels of ANP and BNP mRNA in MPs group significantly reduced after incubation with 48 μg/mL MPs for 48 h compared with ISO group(t = 12. 110 and 3. 526,respectively,each P < 0. 05);The expression levels of CaMK Ⅱand p-CaMKⅡ in ISO group were significantly higher than those in Control group(t = 3. 278 and 4. 181,respectively,each P < 0. 05),while the expression of p-CaMK Ⅱ in MPs group decreased significantly(t = 5. 420,P < 0. 05);The calcium current density in ISO group was significantly higher than that in Control group(t = 15. 261,P < 0. 01),while that in MPs group was significantly lower than that in ISO group(t =6. 216,P < 0. 05).Conclusion MSC-MPs can significantly inhibit ISO-induced cardiomyocyte hypertrophy in rats,which is related to its down-regulation of cardiomyocyte CaMKⅡ and inhibition of L-type calcium channel.

Construction and self-activation detection of yeast two-hybrid bait plasmid of human programmed cell death ligand 1 immunoglobulin variable region domain gene / 中国生物制品学杂志

@#Objective To construct a yeast two-hybrid recombinant bait plasmid of human programmed cell death ligand 1(PD-L1)immunoglobulin variable region(IgV)domain gene,detect its expression in yeast and detect the cytotoxicity and self-activation of PD-L1 IgV protein as well as the interaction between PD-L1 IgV and human thioredoxin(hTrx).Methods Human PD-L1 was analyzed by bioinformatics method,and primers were designed to amplify PD-L1 IgV domain based on the coding region of PD-L1 gene registered in NCBI GenBank database. PCR amplification was carried out with pENTERPD-L1 plasmid as template,and then cloned into yeast two-hybrid bait vector pGBKT7. The recombinant bait plasmid and pGBKT7 empty vector were transformed into Y2HGold yeast cells respectively,and the PD-L1 IgV gene and its expression were detected by PCR and Western blot;Meanwhile,the protein toxicity and self-activation of PD-L1 IgV were detected,and the interaction between PD-L1 IgV and hTrx was detected by drip plate method.Results The bioinformatics analysis results of PD-L1 were consistent with related reports. The recombinant bait plasmid pGBKT7-PD-L1 IgV was correctly constructed,and Y2HGold positive clone was obtained,in which PD-L1 IgV was stably expressed. The empty vector pGBKT7 and recombinant bait plasmid pGBKT7-PD-L1 IgV grew well on SD/-Trp and SD/-Trp/X-α-Gal plates with the same colony size and number and white colony,but they did not grow on SD/-Trp/X-α-Gal/AbA plates,which indicated that PD-L1 IgV protein had no toxicity and no self-activation effect on yeast. The results of drip plates test showed that all experimental groups grew well on SD/-Trp/-Leu plate,while only positive control group grew on SD/-Trp/-Leu/X-α-Gal/AbA plate and showed blue color,which indicated that bait protein PD-L1 IgV and hTrx did not self-activate,and there was no interaction between them.Conclusion Recombinant human PD-L1 IgV bait plasmid was successfully constructed. PD-L1 IgV protein showed no toxicity and self-activation effect on yeast cells,and there was no interaction between PD-L1 IgV and hTrx. Subsequently,hTrx can be used to construct a peptide aptamer library,from which peptide aptamers that specifically bind to PD-L1 IgV can be screened.

A new pyrazine from Hypecoum erectum L / 药学学报

Four pyrazines were isolated from the n-butanol fraction of Hypecoum erectum L. by using various chromatographic methods, including MCI gel, ODS, silica gel and semi-preparative HPLC. The structures of the isolated compounds were identified as hyperectpyrazin A (1), 1′S-(6-methylpyrazin-2-yl)-ethane-1′,2′-diol (2), 2-hydroxymethyl-6-methylpyrazin (3) and pyrazine-2-carboxylic acid (4) by spectroscopy methods (1D NMR, 2D NMR, UV, IR, MS, etc.). The absolute configuration of compound 2 was determined by using the Mo2(OAc)4 induced CD analysis for the first time. Compound 1 was a new compound, compounds 2-4 were isolated from H. erectum for the first time. Compounds 1-4 were evaluated for their inhibition against acetylcholinesterase and nitric oxide generation induced by lipopolysaccharide-RAW264.7 macrophage cells. At a concentration of 50 μmol·L-1, compounds 2 and 4 displayed inhibitory effects on acetylcholinesterase with the inhibition rates of 44.40% and 43.99%, respectively.

Preparation and in vitro evaluation of polylactic acid nanoparticles containing arginine and glucose oxidase / 药学学报

Hydrogen peroxide (H2O2) and nitric oxide (NO) has a short half-life, low bioavailability, poor tumor targeting and systemic adverse reactions in the physiological environment. In this study, phacoemulsification and nano-precipitation were used to synthesize didecyl dimethyl ammonium bromide (DDAB)/polylactic acid nanoparticles (PLA), then L-arginine (L-Arg) and glucose oxidase (GOx)-loaded nanoparticles (GADP) were prepared, and the in vitro antitumor activity was investigated．The particle size, potential, embedding rate and the ability to produce H2O2/NO of the nanoparticles were investigated. Meanwhile, in vitro cell cytotoxicity against human hepatoma cells (HepG2) was evaluated．The results showed that the prepared L-Arg-DDAB/PLA (ADP) nanoparticles were spherical particles. And the particle size and zeta potential were (225.7 ± 6.33) nm and (+23.5 ± 0.12) mV, respectively. The adsorption rate of GOx was 87.23% ± 0.02%. The drug loading of L-Arg was 15.6% ± 0.22%. The pH value of glucose solution and the amount of H2O2 showed that GADP had good catalytic activity. In vitro cytotoxicity experiments showed that blank nanoparticles were nontoxic, while the drug-loaded nanoparticles presented enhanced antitumor effect on HepG2 cells. And can inhibit tumor cell migration. The low dose nano-scale NO delivery system GADP can effectively inhibit the migration of tumor cells and kill tumor cells, thus producing therapeutic benefits.

Prevention and treatment of lipoic acid-niacin on blue-light-induced retinal damage in rats / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the preventive effect and optimal drug dose of lipoic acid-niacin(N2L)against blue light-induced retinal damage in SD rats, and to explore its possible protective mechanism.METHODS: A total of 36 specific pathogen free-grade male SD rats of 150-200 g were selected and randomly divided into normal control group, blue light injury group, N2L low-dose group(1.0 mg/kg), N2L medium-dose group(2.5 mg/kg), N2L high-dose group(5.0 mg/kg), and physiological saline group, with 6 rats in each group. The normal control group was reared in a 12 h dark and light cycle, and the rest of the groups received 9 h of daily light exposure, 3 h of blue light irradiation with a wavelength of 455 nm and an intensity of 3000±50 lx, and 12 h of darkness to establish the injury model, and were exposed to light exposure for 14 d. For 14 consecutive durations, a 1 mL dose of the corresponding drug was injected intraperitoneally. The rats were reared for another 5 d with a regular 12 h light-dark cycle and were examined by electroretinography. Specimens were prepared by over anesthesia, HE staining, and the thickness of the outer nuclear layer was observed under a optical microscope; superoxide dismutases(SOD)activity was detected by CheKineTM SOD Activity Assay Kit; and the retinal Caspase-3, quinone oxidoreductase 1(NQO1), glutathione S transferase(GST), Bcl-2, and Bax protein expression in rat retina were detected by Western blot.RESULTS: The amplitude of b-wave in dark-vision ERG 3.0 and 10.0(cd·s)/m2 stimulated light, b-wave in bright-vision ERG 3.0(cd·s)/m2 stimulated light, and the amplitude of the 2nd wave peak of oscillatory potential were significantly lower in blue light injury group than that in the normal control group(all P&#x0026;#x003C;0.01), while the amplitude was significantly higher in the N2L medium-dose group than in the blue light injury group(all P&#x0026;#x003C;0.05), and was not statistically different from that of the normal control group; the thickness of the retina in the blue light injury group was decreased in the ONL compared with that of the normal control group(P&#x0026;#x003C;0.001), while in the N2L medium dose group, it was thicker than that of the blue light injury group(P&#x0026;#x003C;0.001), and there was no statistically significant difference from the normal control group; SOD activity was significantly higher in the N2L medium-dose group than in the remaining 5 groups(P&#x0026;#x003C;0.05); the expression of Caspase-3, Bax, and NQO1 in the blue light injury group was higher than that of the normal control group(all P&#x0026;#x003C;0.01), and expression of Bax and Caspase-3 was significantly lower in the N2L medium-dose group compared with the blue light injury group(all P&#x0026;#x003C;0.001), whereas GST, NQO1 and Bcl-2 were significantly increased(all P&#x0026;#x003C;0.01).CONCLUSION:A concentration of 2.5 mg/kg N2L can effectively antagonize the damaging effect of blue light on the retina of SD rats, and it is expected to be a preventive and curative drug for it.

Anti-SARS-CoV-2 activity of small molecule inhibitors of cathepsin L / 药学学报

The coronavirus disease 2019 (COVID-19) is an acute infectious disease caused by the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which has led to serious worldwide economic burden. Due to the continuous emergence of variants, vaccines and monoclonal antibodies are only partial effective against infections caused by distinct strains of SARS-CoV-2. Therefore, it is still of great importance to call for the development of broad-spectrum and effective small molecule drugs to combat both current and future outbreaks triggered by SARS-CoV-2. Cathepsin L (CatL) cleaves the spike glycoprotein (S) of SARS-CoV-2, playing an indispensable role in enhancing virus entry into host cells. Therefore CatL is one of the ideal targets for the development of pan-coronavirus inhibitor-based drugs. In this study, a CatL enzyme inhibitor screening model was established based on fluorescein labeled substrate. Two CatL inhibitors IMB 6290 and IMB 8014 with low cytotoxicity were obtained through high-throughput screening, the half inhibition concentrations (IC50) of which were 11.53 ± 0.68 and 1.56 ± 1.10 μmol·L-1, respectively. SDS-PAGE and cell-cell fusion experiments confirmed that the compounds inhibited the hydrolysis of S protein by CatL in a concentration-dependent manner. Surface plasmon resonance (SPR) detection showed that both compounds exhibited moderate binding affinity with CatL. Molecular docking revealed the binding mode between the compound and the CatL active pocket. The pseudovirus experiment further confirmed the inhibitory effects of IMB 8014 on the S protein mediated entry process. In vitro pharmacokinetic evaluation indicated that the compounds had relatively good drug-likeness properties. Our research suggested that these two compounds have the potential to be further developed as antiviral drugs for COVID-19 treatment.

Enhancement of tropane alkaloids biosynthesis in Atropa belladonna hariy root by overexpression of HnCYP82M3 and DsTRI genes / 药学学报

Tropane alkaloids (TAs) are a class of anticholinergic drugs widely used in clinical practice and mainly extracted from plant, among which Atopa belladonna is the main commercial drug source. It is of great industrial value to obtain TAs in large quantities by plant metabolic engineering. In TAs pathway, cytochrome oxidase CYP82M3 catalyze the synthesis of tropinone and then tropinone reductase I (TRI) compete with TRII for tropinone to form tropine leading to the TAs synthesis (drainage). In this study, based on the "increasing flow and drainage" metabolic engineering strategy, two genes, namely HnCYP82M3 and DsTRI from Hyoscyamus niger and Datura stramonium, respectively, were overexpressed in the hair roots of A. belladonna, with a view to promote the TAs accumulation. The HnCYP82M3 gene was cloned from the root of H. niger, and it encoded amino acid with 91.7% sequence identity with AbCYP82M3 from A. belladonna. Overexpression of HnCYP82M3 alone did not affect the content of TAs in hair roots of A. belladonna, indicating that CYP82M3 was not a key enzyme in TAs biosynthesis. Simultaneous overexpression of HnCYP82M3 and DsTRI greatly promoted the accumulation of the three TAs, and the contents of hyoscyamine, anisodamine and scopolamine were 4.97 times, 2.83 times and 2.19 times that of the control, respectively, and the increase amplitude was greater than that of single overexpression of DsTRI. This study showed that the "increasing flow and drainage" strategy of enzyme genes co-expression at branch points was a promising metabolic engineering method to effectively improve the biosynthesis of TAs in A. belladonna, and laid a theoretical and technical foundation for the large-scale industrial acquisition of TAs.

Blumea balsamifera （L.） DC Oil Alleviates LPS-Induced Inflammatory Response in Macrophages by Affecting Arachidonic Acid Metabolism Via NF-κB Nonclassical Pathway / 中山大学学报(医学科学版)

ObjectiveTo study the anti-inflammatory effects of Blumea balsamifera （L.） DC oil （BBO） based on nuclear factor kappa-B （NF-κB） nonclassical and arachidonic acid （AA） pathway. MethodsEffects of BBO on the production of slow reacting substance of anaphylaxis （SRS-A） were detected by the ileal smooth muscle method. The contents of prostaglandin E2 （PGE2） and leukotriene B4 （LTB4） in lipopolysaccharides （LPS） -induced macrophages were detected by ELISA kit. The expression of COX-2， 5-LOX， FLAP and RelB were detected by qRT-PCR. Western blot was performed to detect the effects of BBO on the level of NF-κB nonclassical pathway proteins TNF receptor associated factor 3 （TRAF3）， TNF receptor associated factor 2 （TRAF2）， NF-κB-inducing kinase （NIK）， p100 and RelB. ResultsThe contractile tension of guinea pig ileum was reduced （P<0.001）， and the SRS-A production inhibition rate reached 65.34% at 1mg·mL-1 BBO concentration. Compared with LPS group， BBO reduced the concentrations of PGE2 （P<0.05） and LTB4 （P<0.05）， and decreased the expressions of COX-2 （P<0.05）， 5-LOX （P<0.05） and FLAP （P<0.05） in AA pathway at concentrations of 40-80 μg·mL-1. Moreover， 40-80 μg·mL-1 BBO decreased the concentrations of TRAF3 （P<0.05）， TRAF2 （P<0.05）， and NIK （P<0.05）， and further inhibited the phosphorylation of p100 （P<0.05）， as well as the level of the transcription factor RelB in genes （P<0.05） and proteins （P<0.05） in nonclassical NF-κB pathway， whereas BBO did not cause such changes. ConclusionBBO may potentially exert its anti-inflammatory effects by suppressing the regulatory proteins TRAF3 and TRAF2 and the transcription factor RelB in NF-κB nonclassical pathway. The inhibitory action extending to the induction kinase function of NIK， further hindering the phosphorylation of p100 and its binding with the transcription factor RelB. Consequently， downstream elements in the AA pathway， including the pivotal rate-limiting enzymes COX-2， 5-LOX and FLAP， were altered. This modulation influences the levels of inflammatory mediators such as PGE2 and LTB4.

Clinical significance of determining the level of biliary calprotectin in patients with cholangiocarcinoma or choledocholithiasis / 临床肝胆病杂志

ObjectiveTo investigate the difference in the level of biliary calprotectin between patients with cholangiocarcinoma and those with choledocholithiasis. MethodsClinical data and bile samples were collected from 34 patients with cholangiocarcinoma and 78 patients with choledocholithiasis who were diagnosed and treated with endoscopic retrograde cholangiopancreatography in The First Affiliated Hospital of Anhui Medical University from May 2021 to September 2022. Fluorescence lateral flow immunoassay was used to measure the levels of calprotectin， hemoglobin， and lactoferrin in bile. The Mann-Whitney U test was used for comparison of continuous data between two groups， and the chi-square test was used for comparison of categorical data between two groups； the Spearman correlation test was used for correlation analysis； the DeLong test was used for comparison of the area under the ROC curve （AUC）. ResultsCompared with the choledocholithiasis group， the cholangiocarcinoma group had significant increases in the levels of calprotectin ［4 795.50 （2 286.79‍ ‍—‍ ‍20 179.73） ng/mL vs 411.16 （67.03‍ ‍—‍ ‍1 991.88） ng/mL， Z=5.572， P<0.001］ and fluoride ［115.70 （109.10‍ — ‍125.50） mmol/L vs 106.60 （98.60‍ ‍—‍ ‍114.40） mmol/L， Z=2.702， P=0.007］. The patients with cholangiocarcinoma were further divided into high cholangiocarcinoma group and low cholangiocarcinoma group， and there was no significant difference between the two groups in the level of calprotectin ［3 867.71 （2 235.66‍ — ‍26 407.40） ng/mL vs 4 795.50 （2 361.15‍ — ‍13 070.53） ng/mL， Z=0.129， P>0.05］. Biliary calprotectin level was correlated with white blood cell count， hemoglobin concentration， and lactoferrin concentration in bile （r=0.316， 0.353， and 0.464， all P<0.05）. The ROC curve analysis showed that biliary calprotectin （with a sensitivity of 79.4% and a specificity of 75.6%）， blood CA19-9 （with a sensitivity of 82.4% and a specificity of 78.2%）， and their combination （with a sensitivity of 88.2% and a specificity of 73.1%） had good sensitivity and specificity in the diagnosis of cholangiocarcinoma. ConclusionThere is an increase in the level of biliary calprotectin in patients with cholangiocarcinoma， and therefore， it might become a biomarker for the diagnosis of cholangiocarcinoma.

Cancer immunotherapy with enveloped self-amplifying mRNA CARG-2020 that modulates IL-12, IL-17 and PD-L1 pathways to prevent tumor recurrence

Targeting multiple immune mechanisms may overcome therapy resistance and further improve cancer immunotherapy for humans. Here, we describe the application of virus-like vesicles (VLV) for delivery of three immunomodulators alone and in combination, as a promising approach for cancer immunotherapy. VLV vectors were designed to deliver single chain interleukin (IL)-12, short-hairpin RNA (shRNA) targeting programmed death ligand 1 (PD-L1), and a dominant-negative form of IL-17 receptor A (dn-IL17RA) as a single payload or as a combination payload. Intralesional delivery of the VLV vector expressing IL-12 alone, as well as the trivalent vector (designated CARG-2020) eradicated large established tumors. However, only CARG-2020 prevented tumor recurrence and provided long-term survival benefit to the tumor-bearing mice, indicating a benefit of the combined immunomodulation. The abscopal effects of CARG-2020 on the non-injected contralateral tumors, as well as protection from the tumor cell re-challenge, suggest immune-mediated mechanism of protection and establishment of immunological memory. Mechanistically, CARG-2020 potently activates Th1 immune mechanisms and inhibits expression of genes related to T cell exhaustion and cancer-promoting inflammation. The ability of CARG-2020 to prevent tumor recurrence and to provide survival benefit makes it a promising candidate for its development for human cancer immunotherapy.

Introgression of bacterial leaf blight (BLB) resistant gene, Xa7 into MARDI elite variety, MR219 by marker assisted backcrossing (MABC) approach

Abstract Bacterial leaf blight (BLB) is one of the major rice diseases in Malaysia. This disease causes substantial yield loss as high as 70%. Development of rice varieties which inherited BLB resistant traits is a crucial approach to promote and sustain rice industry in Malaysia. Hence, this study aims were to enhance BLB disease resistant characters of high yielding commercial variety MR219 through backcross breeding approach with supporting tool of marker-assisted selection (MAS). Broad spectrum BLB resistance gene, Xa7 from donor parent IRBB7 were introgressed into the susceptible MR219 (recurrent parent) using two flanking markers ID7 and ID15. At BC3F4, we managed to generate 19 introgressed lines with homozygous Xa7 gene and showed resistant characteristics as donor parent when it was challenged with Xanthomonas oryzae pv. oryzae through artificial inoculation. Recurrent parent MR219 and control variety, MR263 were found to be severely infected by the disease. The improved lines exhibited similar morphological and yield performance characters as to the elite variety, MR219. Two lines, PB-2-107 and PB-2-34 were chosen to be potential lines because of their outstanding performances compared to parent, MR219. This study demonstrates a success story of MAS application in development of improved disease resistance lines of rice against BLB disease.

Resumo A mancha bacteriana das folhas (BLB) é uma das principais doenças do arroz na Malásia. Essa doença causa perdas substanciais de rendimento de até 70%. O desenvolvimento de variedades de arroz que herdaram características de resistência ao BLB é uma abordagem crucial para promover e sustentar a indústria do arroz na Malásia. Portanto, o objetivo deste estudo foi aumentar os caracteres BLB resistentes a doenças da variedade comercial MR219 de alto rendimento por meio de uma abordagem de cruzamento retrocruzamento com ferramenta de apoio de seleção assistida por marcador (MAS). O gene de resistência a BLB de amplo espectro, Xa7 do pai doador IRBB7, foi introgressado no MR219 suscetível (pai recorrente) usando dois marcadores flanqueadores ID7 e ID15. No BC3F4, conseguimos gerar 19 linhagens introgressadas com o gene Xa7 homozigoto e apresentamos características de resistência como genitor doador quando desafiado com Xanthomonas oryzae pv. oryzae por inoculação artificial. O pai recorrente MR219 e a variedade controle, MR263, estavam gravemente infectados pela doença. As linhas melhoradas exibiram características morfológicas e de desempenho de rendimento semelhantes às da variedade elite, MR219. Duas linhas, PB-2-107 e PB-2-34, foram escolhidas como linhas potenciais por causa de seus desempenhos excelentes em comparação com a mãe, MR219. Este estudo demonstra uma história de sucesso de aplicação de MAS no desenvolvimento de linhas de arroz melhoradas com resistência a doenças contra a doença BLB.