The Amazon Basin is a center of diversity of Gossypium barbadense and the strategy for conservation of this genetic resource depends on the knowledge of the diversity maintained in Amazonas State. During two expeditions, in 2012 and 2014, plants were collected in ten municipalities in the state of Amazonas, in the central Brazilian Amazon region. The molecular diversity was estimated by SSR markers for 50 samples collected in 2012. The morphological diversity of 24 plants collected in 2014 was assessed ex situ and compared to that of 50 plants of the same and other cotton varieties from other Brazilian states. Most of plants evaluated in situ in Amazonas had purple petioles and veins (82%), associated to medicinal use, and kidney seeds (78%). The ex situ morphological analysies showed that G. barbadense plants from the Amazonas state: i) presented higher similarity to cotton plants from other northern Brazilian states, and ii) were grouped separately from those of other northern Brazilian states by descriptor analysis. Both the molecular (H=0.41) and morphological (H=0.38±0.02) diversity among the collected plants was considered intermediary. Our study indicates the distinctiveness of Amazon cottons, and contributes to demonstrate the discrimination power of multicategorical traits.KEYWORDS: conservation, genetic resources, cotton tree, phenotypic characterization Diversidade genética de Gossypium barbadense coletado na Amazônia central RESUMOA bacia Amazônica é um centro de diversidade de Gossypium barbadense e a estratégia de manutenção desse recurso genético depende do conhecimento da diversidade da espécie mantida no Estado do Amazonas. Em 2012 e 2014 plantas desta espécie foram coletadas em dez municípios na região centro-leste do Estado. A diversidade molecular por marcadores microssatélites foi mensurada para 50 amostras da coleta de 2012. A diversidade morfológica de 24 plantas coletadas em 2014 foi medida ex situ e comparada com a de 50 amostras desta e de outras variedades de algodão de outros estados do Brasil. A maioria das plantas do Amazonas apresentou folhas arroxeadas (82%), associadas a uso medicinal, e sementes unidas, do tipo rim-de-boi (78%). A análise morfológica ex situ mostrou que G. barbadense coletado no estado do Amazonas: i) tem maior similaridade com plantas da mesma espécie de outros estados da Região Norte do Brasil e ii) se agrupam entre si de forma diferenciada das plantas de outros estados. A diversidade molecular (H = 0,41) e morfológica (H = 0,38 ± 0,02) entre os acessos foi considerada intermediária. Nosso estudo indica o caráter distintivo dos algodões amazônicos, e contribui para demonstrar o poder de discriminação de variáveis multicategóricas.
A pressão de seleção promovida por fungicidas na agricultura estimula mecanismos de variabilidade dos patógenos a desenvolver populações insensíveis a moléculas químicas. Objetivo deste trabalho foi caracterizar a sensibilidade de isolados de C. gloeosporioides a fungicidas in vitro. Oito isolados de C. gloeosporioides (COLL) pertencentes a Coleção Micológica do IFGoiano câmpus Urutaí foram testados in vitro e sua sensibilidade testada para os seguintes fungicidas: i) tiofanato metílico, ii) trifloxistrobina + tebuconazol, iii) piraclostrobina + epoxiconazol, vi) azoxistrobina + ciproconazol, nas concentrações de 0.1, 1, 10, 100 ppm (além do controle). O experimento inteiramente casualizado, em fatorial representado por : fator isolado [8], fator dosagem [5] e fator tipo de fungicidas [4], com duas repetições. O isolado de Colletotrichum oriundo de soja foi o que teve estatisticamente o maior diâmetro de colônia em relação aos demais isolados analisados. A mistura de fungicida trifloxistrobina + tebuconazol foi a que estatisticamente apresentou maior porcentagem de inibição, diferindo estatisticamente dos demais fungicidas analisados. De acordo com o critério adotado a maioria dos isolados adequaram-se na classe dos isolados intermediários, sendo detectado dentre os oito isolados nenhuma população ou isolado com comportamento de insensibilidade ou resistência aos fungicidas utilizados para controle, já que a 100 ppm não houve crescimento micelial de nenhum isolado. As maiores amplitudes de EC50 foram observadas para os fungicidas Trifloxistrobina+tebuconazol e Piraclostrobina+epoxiconazol, demonstrando que entre os isolados testados para esses dois fungicidas existe maior diversidade da sensibilidade a essas moléculas. Através desse trabalho podemos verificar a variabilidade de sensibilidade que isolados Colletotrichum gloesporioides podem apresentar perante as diferentes moléculas utilizadas comercialmente para seu controle.
The Cerrado has a vast diversity of fruit plant species. Among them, the cagaita and mangabeira trees stand out because of their fruits nutritional potential. They propagate through seeds, a method that generates genetically distinct plants. Thus, it would be of interest to propagate these plants through vegetative propagation techniques aiming to select superior and identical genotypes from the mother plant. Therefore, the objective was to establish a methodology for maintenance, survival, and rooting induction of Eugenia dysenterica and Hancornia speciosa var. pubescens in nutrient solution with different sucrose concentrations added with 2.4-dichlorophenoxyacetic auxin (2.4-D). In the cagaita and mangabeira tree cuttings, five sucrose concentrations were evaluated: 0, 5, 10, 15, and 20% for the first; and 0, 10, 20, 30, and 40 % for the second species. In addition to these, the control was deionized water. To the sucrose solution was added 190 g L-1 NH4NO3, Ca3ClO, K2SO 4, and 3.00 mg L -1 of 2.4-D. We also performed a second test for cagaita tree, which was evaluated different doses of 2.4-D: 0, 0.5, 1.0, 1.5, and 2.0 mg L-1; and control (deionized water). In all experiments, the completely randomized design was used. We collected data on survival, contamination, cuttings with permanent leaves, base oxidation, callus formation, and root starts. In the first cagaita tree experiment, cuttings survival was higher than 80%. In the second trial, the use of 2.4-D did not favor the survival of the cuttings, nor did it promote the formation of root starts. For mangabeira was observed survival values of 100% in all treatments evaluated, and root starts were also found in its herbaceous cuttings.
Seed coat tear is frequently occurs in some soybean cultivars. The impact of seed coat tear on seed physiology and sanitation is uncertain. Our objective was to analyze the physiological and pathological effect of tear on soybean (Glycine max) seed coat. The cultivars NS-8338-IPRO (with high incidence of tear) and NS-6906-IPRO (with low incidence of tear) were used. A tetrazolium test was used to assess the physiological quality of the seed coat before and after storage. The sanitary quality was assessed through the "Blotter Test". For each storage period, we evaluated seeds with 0% coat tear, up to 10%, and above 10%. The experiment was performed in a completely randomized design using the methodologies proposed by RAS. The coat tear on soybean seed positively contributed to the moisture damage affecting the inner part of the seed. Incidences of Fusarium sp. and Aspergillus sp. were frequently observed in torn seeds and in seeds without tear (around 9-10%) but did not interfere with seed quality. The appearance of coat tear on soybean seed is increased by moisture damage and do not serve as a gateway for the fungi to cause damage during seed emergence.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.