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1.
Biosci. j. (Online) ; 36(3): 761-767, 01-05-2020. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-1146964

RESUMO

Boron (B) retranslocation may confer greater tolerance to B deficiency or toxicity, resulting in plants and fruits with better nutritional quality. Most plants do not demonstrate phloem mobility for B; however, some plants have natural mobility and others express it under stress conditions, such as nutritional stress. Therefore, we investigated the phloem mobility of B in cherry tomato plants with different nutritional status. The plants were cultivated in nutrient solution with adequate and insufficient doses of Potassium (K) and B. Furthermore, the plants received foliar fertilization with B in a mature leaf (F) in a localized form. The B content and amount in leaves near F were compared with leaves of the same age and position on control plants. The experiment was carried out in a protected environment and conducted in a randomized complete block design in a subdivided plot scheme with four replicates. Re-translocation of B between neighboring leaves was observed when the plant was without K deficiency and with B deficiency. In this nutritional status, leaves next to fertilized leaf with B (F) showed higher B amount when compared to leaves of the same position of control plants. Evidence suggests that retranslocation of B over relatively short distances (between leaves) can be influenced by the nutritional status the cherry tomato plants.


A retranslocação de Boro (B) pode conferir maior tolerância à deficiência ou toxidez de B, resultando em plantas e frutos com melhor qualidade nutricional. A maioria das plantas não demonstra mobilidade floemática para o B, contudo, algumas plantas possuem mobilidade natural e outras a expressam sob condições de estresse, como o estresse nutricional. Nesse sentido, foi investigada a mobilidade floemática do B em plantas de tomate cereja com diferentes status nutricionais. As plantas foram cultivadas em solução nutritiva com doses adequada e insuficiente de Potássio (K) e B. Adicionalmente, as plantas receberam, de forma localizada, fertilização foliar com B em uma folha madura (F). Os teores e os conteúdos de B nas folhas vizinhas a F foram comparados com folhas de mesma idade e posição de plantas controle. O experimento foi realizado em ambiente protegido e conduzido no delineamento de blocos casualizados em esquema de parcelas subdivididas com quatro repetições. Evidenciou-se retranslocação de B entre folhas vizinhas quando a planta estava sem deficiência de K e com deficiência de B. Neste status nutricional, as folhas vizinhas à folha aplicada (F) apresentaram maiores teores e conteúdos de B quando comparadas às folhas de mesma posição das plantas controle. As evidências sugerem que a retranslocação de B em distâncias relativamente curtas (entre folhas) pode ser influenciada pelo status nutricional de plantas de tomate cereja.


Assuntos
Potássio , Boro , Solanum lycopersicum , Floema
2.
Rev. Inst. Adolfo Lutz ; 79: e1791, 31 mar. 2020. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1489612

RESUMO

O açúcar de coco vem se tornando popular no Brasil e no mundo devido às alegações nutricionais de ser um adoçante natural e mais saudável em relação a outros açúcares. Sua produção ocorre de forma artesanal a partir da extração da seiva do floema da inflorescência da palmeira. Este trabalho teve por objetivo analisar microscopicamente a identidade e a presença de matérias estranhas em amostras de açúcar de coco, bem como verificar sua conformidade em relação às legislações sanitárias brasileiras. Foram analisadas 13 amostras comerciais de açúcar de coco da cidade de São Paulo quanto aos ensaios de pesquisa e identificação de elementos histológicos e pesquisa de matérias estranhas. A identificação de elementos histológicos vegetais revelou a presença de amidos morfologicamente semelhantes ao padrão de Triticum sp. (trigo), Manihot sp. (mandioca) e Oryza sativa (arroz), além de amidos alterados. Também foram encontrados elementos histológicos vegetais compatíveis com padrão de Saccharum officinarum (cana-de-açúcar) e de Cocos nucifera (coco). Todas as amostras analisadas continham matérias estranhas com predomínio de fragmentos de insetos em 100% delas. Os resultados do estudo indicam falhas nas Boas Práticas de produção do açúcar de coco e a necessidade da adequação deste produto em relação às normas vigentes.


Coconut sugar has become popular in Brazil and worldwide due to the nutritional claims of being a natural and healthier sweetener compared to other sugars. Its production takes places in an artisanal way from the extraction of phloem sap from the inflorescence of the palm. The aim of this work was to microscopically analyze the identity and the presence of foreign matter in samples of coconut sugar, as well as to verify its compliance with Brazilian health legislation. Thirteen commercial samples of coconut sugar from the city of São Paulo were analyzed for the research and identification of histological elements and foreign matter. The identification of vegetable histological elements revealed the presence of starches morphologically similar to the Triticum sp. (wheat), Manihot sp. (cassava) and Oryza sativa (rice) pattern, besides altered starches. Vegetable histological elements compatible with the Saccharum officinarum (sugar cane) and Cocos nucifera (coconut) pattern were also found. All samples analyzed contained foreign matter with predominance of insect fragments in 100% of the samples. The results of the study indicate flaws in the Good Practices for the production of coconut sugar and the need to adapt this product to current standards.


Assuntos
Alimentos de Coco , Análise de Alimentos , Açúcares/química , Cocos , Floema , Boas Práticas de Fabricação , Brasil , Fraude , Inocuidade dos Alimentos , Vigilância Sanitária
3.
Braz. arch. biol. technol ; 63: e20180670, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132160

RESUMO

Abstract Studies evaluating the influence of nutrients on plant anatomy are very important because nutritional deficiencies can alter the thickness and shape of certain tissues, compromising their functionality what can explain the reduction of productivity. The aim of this study was to characterize the anatomical changes in cherry tomato plants subjected to calcium (Ca) and magnesium (Mg) deficiencies. The experiment was conducted in nutrient solution and the plants subjected to three treatments: complete solution (Control), Ca restriction (1 mmol L-1 of Ca) and Mg omission (without Mg). The experimental design was completely randomized, with three repetitions. Sixty days after seedling transplanting leaves and stem were collected and submitted to anatomical evaluations. Ca or Mg deficiency promotes most evident anatomical changes in chlorophyllous and vascular tissues of the leaves, rather than in the stems. Leaves of 'Sindy' tomato plants with a concentration of 1.7 g kg-1 of Mg and visual symptoms of Mg deficiency present hyperplasia of both tissues, phloem and xylem. This deficiency also promotes increases in the thickness of mesophyll, spongy parenchyma and palisade parenchyma, and consequently of leaf thickness. The midrib of the leaves with a concentration of 10 g kg-1 of Ca, without visual symptoms of deficiency presented phloem hypertrophy and hyperplasia.


Assuntos
Cálcio/análise , Solanum lycopersicum/química , Caules de Planta/química , Folhas de Planta/química , Magnésio/análise , Floema/metabolismo , Xilema/metabolismo
4.
Acta sci., Biol. sci ; 41: e47548, 20190000. ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460874

RESUMO

Trigona spinipes Fabricius (Apidae: Meliponini), is a common stingless bee widely seen in urban and rural areas in Brazil, popularly known as irapuá, arapuá or bee-dog. Although these bees are considered pollinators of some cultivated plants, they are better known for the damage they cause in different crops. During experimental agroecological cultivation of Artemisia (Artemisia annuaLinn, Asteraceae), in Jaguariúna (SP, Brazil), stingless bees Trigona spinipes (Fabricius) were observed sucking phloem sap directly from the plant, a phenomenon not yet described in scientific literature. This study aimed to register and describe the phloem sap-sucking behavior performed by T. spinipesfor the first time, as well as to assess the potential impact of this behavior on A. annuacultivation. The behavior and the material collected by bees and the severity of attack were also analyzed. The aging and premature death of observed A. annuaspecimens occurred because of extensive lesions caused by T. spinipes, confirming the negative consequence of sap-sucking attacks of T. spinipesbees on the plants. Factors that could induce this unusual behavior were presented, pointing out the need for future studies on the development of strategies to protect plants, without causing damage to the T. spinipesbee populations, which are elements of Brazilian bee fauna and, therefore, protected by law.


Assuntos
Animais , Abelhas/química , Artemisia annua/citologia , Floema/química , Plantas Medicinais , Agricultura Orgânica
5.
China Journal of Chinese Materia Medica ; (24): 2862-2866, 2009.
Artigo em Chinês | WPRIM | ID: wpr-315348

RESUMO

<p><b>OBJECTIVE</b>To find the difference of the shapes and properties and the microscopic frameworks between wild and cultivated Radix Saposhnikovia.</p><p><b>METHOD</b>The shapes and properties, the characters of transverse section, the powder and disintegrated tissue of roots of medical materials were compared by microscopic measuring.</p><p><b>RESULT</b>Wild Radix Saposhnikovia had a long conical or cylindrical root, and fewer root branches. It showed a close annulus grain on top root, cortical section of root in light brown colour, many brown oil spots and possessed typical odor, While cultivated Radix Saposhnikovia had many root branches, and showed less annulus grain on top root, cortical section of root in light yellow brown colour, less brown oil spots and possessed light odor. The difference of microscopic histological structure was that wild Radix Saposhnikovia had phloem transverse section of root with many rotundity oil tube lining up 10-22 rings, xylem vessel with radiate rank, and indistinct annual ring. While cultivated Radix Saposhnikovia had phloem transverse section of root with oil tube lining up 10-11 rings and xylem vessel with distinct annual ring.</p><p><b>CONCLUSION</b>There exists several differences between wild and cultivated Radix Saposhnikovia in shapes and properties and differences of microscopic frameworks. The main characteristics are the differences of shapes and numbers of oil tube of phloem transverse section of root. The cultivated Radix Saposhnikovia of 1-4 years can be recognized by annual rings of xylem vessel.</p>


Assuntos
Apiaceae , Química , Biologia Celular , Microscopia , Floema , Química , Biologia Celular , Raízes de Plantas , Química , Biologia Celular , Xilema , Química , Biologia Celular
6.
Rev. biol. trop ; 53(1/2): 29-48, mar.-jun 2005. ilus, tab
Artigo em Inglês | LILACS | ID: lil-455484

RESUMO

Wood and bark anatomy and histochemistry of Acacia bilimekii Humb. & Bonpl., Acacia cochliacantha Mcbride., Conzatia multiflora (Rob) Stand. and Guazuma ulmifolia Lam.are described from stem samples collected in a tropical dry forest (Morelos,Mexico). Enzyme activities were tested in tangential, radial and transverse cuts of fresh material. Histochemistry and stem anatomy were studied on similar cuts previously softened in a solution of water-glicerol-PEG. Our results show that the anatomical patterns of bark and wood, as well as the histochemical patterns and specific gravity, are influenced by water accessibility and climate; these patterns could guarantee mechanical and anti-infection strategies to support extreme conditions. Enzyme cytochemistry reveals biochemical activities probably related to lipid utilization routes for the lignification processes and for synthesis of extractives; these results suggest that the formation and maturation of woody tissue is very active at the beginning of the rainy season. These species are widely used by the local population. Traditional uses include firewood, dead and live fences, fodder, construction, supporting stakes, handcrafts, farming tools, extraction of tanning products, and medicine. There is no relationship between use and abundance. Alternative uses are proposed according to a density index


Se estudió la anatomía e histoquímica del tallo secundario de Acacia bilimekii, Acacia cochliacantha, Conzatia multiflora y Guazuma ulmifolia. Las muestras de tallo se colectaron en una selva baja caducifolia del estado de Morelos, México. La actividad enzimática se estudió en cortes frescos de caras tangenciales, radiales y transversales. La anatomía e histoquímica se hizo en cortes similares de muestras previamente ablandadas con una mezcla de agua-glicerol-PEG. Los resultados muestran que el patrón anatómico de la corteza y madera, así como las características histoquímicas no enzimáticas están relacionados con el acceso al agua y el clima; estos patrones garantizan que las estrategias mecánicas de resistencia al deterioro les permitan sobrevivir a condiciones extremas. Los resultados de la histoquímica y la citoquímica enzimática sugieren que la lignificación y la síntesis de extractivos a partir de los lípidos de reserva se encuentra activa desde el principio de la estación de lluvias. Se sugieren usos potenciales para las especies estudiads de acuerdo con las densidades relativas


Assuntos
Fabaceae/anatomia & histologia , Casca de Planta/anatomia & histologia , Caules de Planta/anatomia & histologia , Malvaceae/anatomia & histologia , Árvores/anatomia & histologia , Madeira , Madeira/anatomia & histologia , Fabaceae/classificação , Fabaceae/enzimologia , Sensação Gravitacional , México , Floema/anatomia & histologia , Floema/enzimologia , Casca de Planta/enzimologia , Caules de Planta/enzimologia , Malvaceae/classificação , Malvaceae/enzimologia , Clima Tropical , Árvores/classificação , Árvores/enzimologia , Madeira/enzimologia
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