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Search Results: 1 - 10 of 22448 matches for " Francisco Guilhien;Cicero "
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X-Ray analysis to assess mechanical damage in sweet corn seeds
Gomes Junior, Francisco Guilhien;Cicero, Silvio Moure;
Revista Brasileira de Sementes , 2012, DOI: 10.1590/S0101-31222012000100010
Abstract: the x-ray test is a precise, fast and non-destructive method to detect mechanical damage in seeds. in the present study, the efficiency of x-ray analysis in identifying the extent of mechanical damage in sweet corn seeds and its relationship with germination and vigor was evaluated. hybrid 'swb 551' (sh2) seeds with round (r) and flat (f) shapes were classified as large (l), medium (m1, m2 and m3) and small (s), using sieves with round and oblong screens. after artificial exposure to different levels of damage (0, 1, 3, 5 and 7 impacts), seeds were x-rayed (15 kv, 5 min) and submitted to germination (25 °c/5 days) and cold (10 °c/7 days) tests. digital images of normal and abnormal seedlings and ungerminated seeds from germination and cold tests were jointly analyzed with the seed x-ray images. results showed that damage affecting the embryonic axis resulted in abnormal seedlings or dead seeds in the germination and cold tests. the x-ray analysis is efficient for identifying mechanical damage in sweet corn seeds, allowing damage severity to be associated with losses in germination and vigor.
Computerized imaging analysis of seedlings for assessment of physiological potential of wheat seeds Análise computadorizada de imagens de plantulas para avalia o do potencial fisiológico de sementes de trigo
Vanessa Neumann Silva,Francisco Guilhien Gomes Junior,Silvio Moure Cicero
Revista Brasileira de Sementes , 2012, DOI: 10.1590/s0101-31222012000400009
Abstract: Nowadays, image analysis is one of the most modern tools in evaluating physiological potential of seeds. This study aimed at verifying the efficiency of the seedling imaging analysis to assess physiological potential of wheat seeds. The seeds of wheat, cultivars IAC 370 and IAC 380, each of which represented by five different lots, were stored during four months under natural environmental conditions of temperature (T) and relative humidity (RH), in municipality of Piracicaba, Stated of S o Paulo, Brazil. For this, bimonthly assessments were performed to quantify moisture content and physiological potential of seeds by means of tests of: germination, first count, accelerated aging, electrical conductivity, seedling emergence, and computerized analysis of seedlings, using the Seed Vigor Imaging System (SVIS ). It has been concluded that the computerized analyses of seedling through growth indexes and vigor, using the SVIS , is efficient to assess physiological potential of wheat seeds. Análise de imagens para avalia o do potencial fisiológico de sementes é uma das ferramentas mais modernas existentes atualmente. O objetivo deste estudo foi verificar a eficiência do sistema de análise computadorizada de plantulas para avalia o do potencial fisiológico de sementes de trigo. Sementes de trigo, das cultivares IAC 370 e IAC 380, cada uma delas representadas por cinco lotes diferentes, foram armazenadas durante quatro meses nas condi es ambientais naturais de temperatura e umidade relativa do ar em Piracicaba, SP. Para isso, foram realizadas avalia es bimestrais para quantificar o teor de água e o potencial fisiológico das sementes, por meio dos testes de: germina o, primeira contagem de germina o, envelhecimento acelerado, condutividade elétrica, emergência de plantulas e análise computadorizada de plantulas, por meio do Seed Vigor Imaging System (SVIS ). Concluiu-se que a análise computadorizada de plantulas, por meio dos índices de crescimento e vigor é eficiente para a avalia o do potencial fisiológico de sementes de trigo.
Utiliza??o da análise computadorizada de plantulas na avalia??o do potencial fisiológico de sementes de amendoim tratadas com fungicida e inseticida
Marchi, José Luís de;Cicero, Silvio Moure;Gomes Junior, Francisco Guilhien;
Revista Brasileira de Sementes , 2011, DOI: 10.1590/S0101-31222011000400007
Abstract: peanut seeds are considered difficult to produce because they often show unsatisfactory levels of germination and vigor due to many factors, including problems associated with fungi and a high sensitivity to mechanical injuries. in addition to treating peanut seeds with a fungicide, treatment with insecticides to control soil insect pests in the early growth stages is recommended. besides using the routine tests for evaluating the physiological potential of peanut seeds, computer analysis of seedlings has great potential because it is accurate, quick and without any human interpretation errors. this study aimed to evaluate the physiological potential and sanitary quality of peanut seeds treated with a fungicide, an insecticide, and a combination of both, using computerized analysis of seedlings. seeds of the cultivar iac 886, untreated and treated with the fungicide maxim xl (fludioxonil + metalaxyl), the insecticide cruiser 350 fs (thiamethoxam) and with a mixture of both products, were stored for periods of 0, 15, 30, 45, 60, 90 and 180 days (20 °c, 50% air rh). after each storage period, seeds were evaluated for moisture content, germination, accelerated aging, seedling emergence in the field, electrical conductivity and seed pathology, as well as a computer analysis of the seedlings. it was concluded that computer analysis of peanut seedlings has an efficiency which is equivalent to tests on seeds for accelerated aging and seedling emergence in the field for identifying treatment differences in the absence or presence of a fungicide and a fungicide associated with an insecticide.
Avalia??o de danos mecanicos em sementes de feij?o por meio da análise de imagens
Mondo, Vitor Henrique Vaz;Gomes Junior, Francisco Guilhien;Pupim, Túlio Louren?o;Cicero, Silvio Moure;
Revista Brasileira de Sementes , 2009, DOI: 10.1590/S0101-31222009000200003
Abstract: bean seed (phaseolus vulgaris l.) quality is greatly affected by harvesting, drying, handling and storage activities during the seed production process. in these operations, seeds collide repeatedly against metal surfaces predisposing them to mechanical damage. in this context, this investigation studied the effect of the amount and different impact pressures on bean seed quality. seeds from one lot of the iac-carioca dry bean cultivar were thrown by means of an air jet at two different pressures (551.6 and 965.3 kpa) one, three and five times against a metal surface positioned at a distance of 30cm. a factorial squeme was used with two evaluation times (before and after storage), two pressures and three numbers of impacts. mechanical damage was evaluated by image analysis using x-rays of the seeds and digital photographs of the seedlings. seed physiological quality was evaluated by germination and vigor tests before and after four months storage. the results showed a direct relationship between the increase in the amount and pressures of impact and the decrease in seed physiological quality; the impact pressure provided more severe and immediate effects than the number of impacts. the image analysis technique allowed the understanding of the effect of the mechanical damage that appeared inside the seeds. in this way image analysis proved to be an interesting technique to study mechanical damage in bean seeds.
Análise de imagens na avalia??o de danos mecanicos em sementes de soja
Pinto, Taís Leite Ferreira;Mondo, Vitor Henrique Vaz;Gomes-Júnior, Francisco Guilhien;Cicero, Silvio Moure;
Pesquisa Agropecuária Tropical , 2012, DOI: 10.1590/S1983-40632012000300010
Abstract: mechanical damage is one of the most important factors in the soybean seeds quality decrease. this study aimed at evaluating the influence of impact pressure and seed moisture content, as well as the applicability of image analysis, on mechanical damages in soybean seeds. vencedora and monsoy 8001 cultivars seeds, with moisture content of 13% and 18%, were submitted to mechanical damages, with the aid of an impact simulator equipment (551.6 kpa and 965.3 kpa). subsequently, the seeds were dried at 32oc up to 12% of moisture content. immediately after the impacts and after five months of storage, the seeds were submitted to the tetrazolium and x-rays tests. the impact pressure and seed moisture content directly affected the mechanical damages severity, however, the impact location presented a higher influence than those factors. the image analysis method was very useful for evaluating mechanical damages in soybean seeds, enabling a detailed analysis of different factors effects.
Spatial variability of soil fertility and its relationship with seed physiological potential in a soybean production area
Mondo, Vitor Henrique Vaz;Gomes Junior, Francisco Guilhien;Pinto, Taís Leite Ferreira;Marchi, José Luis de;Motomiya, Anamari Viegas de Araújo;Molin, José Paulo;Cicero, Silvio Moure;
Revista Brasileira de Sementes , 2012, DOI: 10.1590/S0101-31222012000200002
Abstract: the correlation of soil fertility x seed physiological potential is very important in the area of seed technology but results published with that theme are contradictory. for this reason, this study to evaluate the correlations between soil chemical properties and physiological potential of soybean seeds. on georeferenced points, both soil and seeds were sampled for analysis of soil fertility and seed physiological potential. data were assessed by the following analyses: descriptive statistics; pearson's linear correlation; and geostatistics. the adjusted parameters of the semivariograms were used to produce maps of spatial distribution for each variable. organic matter content, mn and cu showed significant effects on seed germination. most variables studied presented moderate to high spatial dependence. germination and accelerated aging of seeds, and p, ca, mg, mn, cu and zn showed a better fit to spherical semivariogram: organic matter, ph and k had a better fit to gaussian model; and v% and fe showed a better fit to the linear model. the values for range of spatial dependence varied from 89.9 m for p until 651.4 m for fe. these values should be considered when new samples are collected for assessing soil fertility in this production area.
Incidência de patógenos e vigor de sementes de milho doce submetidas a danos mecanicos
Gomes Junior, Francisco Guilhien;Timóteo, Tathiana Silva;Kobori, Nilce Naomi;Pupim, Túlio Louren?o;Gagliardi, Bruna;Carvalho, Tereza Cristina de;Moraes, Maria Heloisa Duarte de;Menten, José Otávio Machado;Cicero, Silvio Moure;
Summa Phytopathologica , 2009, DOI: 10.1590/S0100-54052009000300003
Abstract: the objective of this study was to evaluate pathogen incidence and vigor in different size classes of sweet corn seeds, after mechanical damage. hybrid seeds 'swb551' dow agrosciences? were classified by sieves with different sizes and forms (rg, rm1, rm2 and rp, with circular sieves of 8.7, 7.9, 7.1 and 6.4 mm of diameter, respectively, and cg, cm and cp with oblong sieves with dimensions of 8.7 x 19.0, 7.9 x 19.0, 6.4 x 19.0 mm, respectively). seeds were submitted for impacts against a metallic plate in order to have different intensities of mechanical damage (0, 1, 3, 5 and 7 impacts) and stored at the temperature of 20oc and 50-60% of relative humidity. the experimental design was a completely randomized with four repetitions, performing a factorial 7 x 5 (7 sieves and 5 damages intensities), totalizing 35 treatments. seeds water content, mechanical damage (iodine dyeing), germination test, cold test and seed health test were evaluated. variations in the incidence of pathogens among seeds with different sizes and forms were evidenced. increasing mechanical damage did not favor increasing of pathogens incidence in seeds; however, it caused reduction on seed vigor.
Proteína e qualidade de sementes de feij?o (Phaseolus vulgaris L.) em fun??o da aduba??o nitrogenada em plantio direto
Gomes Junior, Francisco Guilhien;Sá, Marco Eustáquio De;
Revista Brasileira de Sementes , 2010, DOI: 10.1590/S0101-31222010000100004
Abstract: nitrogen limitation in the common bean (phaseolus vulgaris l. ) produces reduced productivity and seeds with low protein content and physiological quality. we assessed the effects of nitrogen fertilizer side dressing on the protein content and physiological quality of the seeds of p. vulgaris l. cultivars (cv.) ipr juriti and pérola grown in plots (soil type = dystrophic red latosol) using a no-tillage system under a thick mulch of millet residues at the experimental station of unesp - ilha solteira campus, located in selvíria, ms (k?ppen climate type = aw) during autumn (march/june) and winter (june/september) 2005. for each cultivar, a randomized block experimental design was used with four replicates and factorially arranged treatments equivalent to 0, 30, 60, 90 and 120 kg.ha-1 added nitrogen (as urea, containing 45% of n) applied as a side dressing during the v4-3 and v4-6 phenological stage corresponding to the 3rd and 6th completely opened trifoliolate leaf on the main stem. supplementation with up to 120 kg.ha-1 nitrogen promoted a greater increase in crude protein at v4-3 (unsupplemented = 17.6% and 16.3%; 120 kg.ha-1 n = 24.1% and 22.3% for cv. ipr juriti and pérola, respectively) than at v4-6 (unsupplemented = 19.2% and 18.3%; 120 kg.ha-1 n = 21.3% and 20.3% for cv. ipr juriti and pérola, respectively). about 90% of the crude protein from cv. ipr juriti was composed of soluble protein compared to 72% for the cv. pérola. albumins and globulins represented about 80% of the soluble protein and prolamins were lower at 0.6%. in conclusion, nitrogen fertilization up to 120 kg.ha-1 applied as a side dressing at the v4-3 phenological stage in no-tillage under a thick mulch of millet promoted a greater increase of crude protein in common bean seeds than at the v4-6 stage. the highest accumulation of soluble protein occurred at 90 kg.ha-1 applied nitrogen without having a significant influence on the physiological quality of the seeds.
Aduba??o nitrogenada no feijoeiro em sistema de semeadura direta e preparo convencional do solo
Gomes Junior, Francisco Guilhien;Sá, Marco Eustáquio de;Muraishi, Cid Tacaoca;
Acta Scientiarum. Agronomy , 2008, DOI: 10.4025/actasciagron.v30i5.5967
Abstract: nitrogen fertilizer is necessary for high yields in common bean crops and n responses under conditions of no-tillage and conventional systems are still basic needs. thus, the objective of this research was to evaluate the effect of n application and common bean yield in no-tillage and conventional systems. the experimental design was a randomized block in a factorial scheme (2x8 + 1) with four replications. the treatments were constituted by the combination of two n doses (40 and 80 kg ha-1) applied at side dressing at eight distinct stadia during vegetative development of the common bean (v4-3, v4-4, v4-5, v4-6, v4-7, v4-8, v4-9 e v4-10), in addition to a control plot without n in side dressing. the experiment was conducted over two years (2002 and 2003) in no-tillage on millet crop residues and conventional plow system. it was concluded that n fertilizer at the v4 stadium of common bean promotes similar seed yields in no-tillage and conventional systems. yield differences between no-tillage and conventional systems are inconsistent in the same agricultural area.
Assessment of physiological potential of cucumber seeds using the software Seedling Vigor Imaging System? (SVIS?)
Chiquito, Adrielle Aparecida;Gomes Junior, Francisco Guilhien;Marcos-Filho, Julio;
Revista Brasileira de Sementes , 2012, DOI: 10.1590/S0101-31222012000200010
Abstract: the software seed vigor imaging system (svis?), has been successfully used to evaluate seed physiological potential by automated analyses of scanned seedlings. in this research, the efficiency of this system was compared to other tests accepted for assessing cucumber (cucumis sativus l.) seed vigor of distinct seed lots of supremo and safira cultivars. seeds were subjected to germination, traditional and saturated salt accelerated aging, seedling emergence, seedling length and svis analyses (determination of vigor indices and seedling growth uniformity, lengths of primary root, hypocotyl and whole seedlings). it was also determined whether the definition of seedling growth/uniformity ratios affects the sensitivity of the svis?. results showed that analyses svis have provided consistent identification of seed lots performance, and have produced information comparable to those from recommended seed vigor tests, thus demonstrating a suitable sensitivity for a rapid and objective evaluation of physiological potential of cucumber seeds. analyses of four-days-old cucumber seedlings using the svis? are more accurate and growth/uniformity does not affect the precision of results.
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