Genetic variability and heterotic groups of Brazilian popcorn populations   总被引：1，自引：1，他引：0  

Glauco Vieira Miranda  Leandro Vagno de Souza  João Carlos Cardoso Galvão  Lauro José Moreira Guimarães  Aurélio Vaz de Melo  Izabel Cristina dos Santos 《Euphytica》2008,162(3):431-440

The development of successful advanced lines and cultivars in maize is dependent on parental selection and assignment to defined heterotic groups. So, the objectives of this study were to evaluate genetic variability and identify heterotic groups among Brazilian popcorn varieties. Thus, diallel crosses of advanced generations of the popcorn hybrids, IAC 112 and Zélia, and of three open-pollinated popcorn varieties, RS 20, Branco, and SAM were performed. Ten hybrid combinations, the five parents, and five check treatments were arranged in a block design with four replicates in two tropical-zone locations (CWb climate). Both additive and non-additive effects were important for grain yield, plant height, ear height, and husk cover. For popping expansion, only the additive effects were important. Hybrid combinations between the local variety (Branco) and F₂ populations (IAC 112 and Zelia) resulted in the third and fourth highest values for popping expansion. The best grain yields were obtained with hybrid combinations involving SAM. Cultivars Zélia, IAC 112, and RS 20 increased popping expansion, whereas cultivar Branco increased grain yield of hybrid combinations. The following conclusions may be drawn: Brazilian popcorn populations have reduced heterosis and genetic variability to popping expansion in relation commercial cultivars; there is genetic variability among Brazilian popcorn populations that allows the exploitation of additive and non-additive effects for grain yield; it is possible to increase grain yield by using local varieties; but it would be difficult to obtain commercial hybrids from local varieties because they have poor performance for popping expansion.  相似文献   

Production of transgenic adult plants from clementine mandarin by enhancing cell competence for transformation and regeneration   总被引：3，自引：0，他引：3  

Cervera M  Navarro A  Navarro L  Peña L 《Tree physiology》2008,28(1):55-66

Genetic transformation of mature trees is difficult because adult tissues are recalcitrant to Agrobacterium tumefaciens infection and transformation and because transgenic mature events are less competent for regeneration. We have shown that reinvigoration allows manipulation of the vegetative phase to increase the potential for transformation and regeneration without loss of competence for flowering and fruiting. To produce transgenic plants from clementine mandarin (Citrus clementina hort. ex Tanaka), we optimized the conditions of the source material both ex vitro and in vitro. Grafting of mature buds on juvenile rootstocks in the spring and preventing multiple bud sprouting by removing all but one bud permitted selection of vigorous first flushes for in vitro culture. Use of additional virulence genes from A. tumefaciens to increase transformation frequency and optimization of culture media and conditions to enhance explant cell competence for T-DNA integration and organogenesis resulted in efficient and reliable transgenic plant production. Transformed regenerants from explants, cultured in media without antibiotics, were identified by a screenable marker (either beta-glucuronidase or green fluorescent protein (GFP)), creating the possibility of generating transgenic clementine plants without antibiotic resistance marker genes. Stable integration of foreign genes was demonstrated by Southern blot analysis, and expression of these foreign genes was confirmed by detection of GFP fluorescence in leaves, floral organs and fruits of the transgenic plants.  相似文献   

Differentiation of Bean pod mottle virus isolates based upon host symptoms     

Leandro A. Mozzoni  Pengyin Chen  Rose C. Gergerich 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(1):133-140

Accessions from Glycine, Phaseolus, and Vigna genera were screened for their reactions to different subgroups of isolates of Bean pod mottle virus (BPMV) in order to establish a differential host system. Screening results indicated that the BPMV isolates differed in pathogenic aggressiveness but not in virulence. No major resistance genes were found in soybean (Glycine max) or G. soja since all screened accessions showed mosaic or necrotic symptoms to BPMV inoculation. However, these accessions expressed differences in severity of symptoms when challenged by various BPMV isolates. The inoculation of G. tomentella accessions did not result in mosaic symptoms, and some accessions did not support systemic infection of some of the isolates. Resistance, presented as a hypersensitive reaction, was observed in some of Phaseolus and Vigna genotypes, and resistant response or susceptibility was stable to all the isolates used in the screening. In conclusion, the selected G. soja genotypes PI 407019, PI 464889A, and PI 464928, and ‘Amsoy 71’ soybean may help to separate severe (reassortant) from mild isolates of BPMV based upon their phenotypic reactions.  相似文献   

Use of White Fat as a Replacement for Squid Liver Oil in Practical Diets for Surubim Pseudoplatystoma coruscans     

Ricardo C.  Martino Lulz C.  Trugo José Eurico  P. Cyrino Leandro  Portz 《Journal of the World Aquaculture Society》2003,34(2):192-202

The effect of dietary lipid on culture performance, fatty acid composition of carcass, and the liver polar lipid of surubim fingerlings Pseudoplatystoma coruscans was investigated. Five isonitrogenous (46.5% crude protein) and isolipidic (19% crude lipid) diets were formulated with squid liver oil (SLO) and white fat (pig lard-PL) as lipid sources. Diet 1 was supplemented with 12% SLO, diet 2 with 8% SLO and 4% PL, diet 3 with 6% SLO and 6% PL, diet 4 with 4% SLO and 8% PL, and diet 5 with 12% PL. Fish were fed to apparent satiation over a 64-d feeding trial. No statistically significant difference ( P >0.05) was observed in growth performance of fish. In contrast, fatty acid profile of fish carcass and liver polar lipid fraction was affected ( P 0.05) by dietary fatty acid composition. Palmitic (16:O) and the oleic (18:1n-9) acids were the major saturated and monoene fatty acids respectively found in fish carcass, independent of the lipid source in the diets. The total amount of saturated and monoene fatty acids was significantly higher ( P 0.05) in the carcass of the fish fed diets 4 and 5, than in the other fish. The concentration ( P 0.05) of eicosapentaenoic and docosahexaenoic acids and the n-3/n-6 ratio in fish carcass and in polar lipid fraction of liver increased in direct proportion to the level of squid liver oil in diet. Results of this experiment clearly demonstrated that both squid liver oil and pig lard have a positive nutritive value for surubim and that it is possible to increase the n-3 to n-6 ratio in favor of n-3, without loss in the growth performance, feeding fish with a diet containing a lipid source rich in this fatty acid.  相似文献   

Nutritional planning for Nellore heifers post-weaning to conception at 15 months of age: performance and nutritional,metabolic, and reproductive responses     

de Almeida  Daniel Mageste  Marcondes  Marcos Inácio  Rennó  Luciana Navajas  Pereira Silva  Luiz Henrique  Martins  Leandro Soares  Marquez  David Esteban Contreras  Castaño Villadiego  Faider Alberto  Velez Saldarriaga  Felipe  Franco  Julian David Castaño  Moreno  Deilen Paff Sotelo  de Moura  Felipe Henrique  Paulino  Mário Fonseca 《Tropical animal health and production》2019,51(1):79-87

Tropical Animal Health and Production - The objective of this study was to evaluate the effects of strategic supplementation in the dry period and dry/rainy transition period on the performance and...  相似文献   

Does supplementation of beef calves by creep feeding systems influence milk production and body condition of the dams?     

Sidnei Antônio Lopes  Mário Fonseca Paulino  Edenio Detmann  Ériton Egídio Lisboa Valente  Lívia Vieira de Barros  Luciana Navajas Rennó  Sebastião de Campos Valadares Filho  Leandro Soares Martins 《Tropical animal health and production》2016,48(6):1241-1246

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Nitrogen metabolism in lambs fed diets containing peach palm meal     

Alana Batista dos Santos  Mara Lúcia Albuquerque Pereira  Herymá Giovane de Oliveira Silva  Gleidson Giordano Pinto de Carvalho  Leandro Sampaio Oliveira Ribeiro  Taiala Cristina de Jesus Pereira  José Augusto Gomes Azevêdo  Larisse Borges Sousa  LeandroBorges Sousa  Paulo José Presídio Almeida 《Tropical animal health and production》2016,48(7):1491-1495

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Natural antimicrobials for control of Salmonella Enteritidis in feed and in vitro model of the chicken digestive process     

Geovane R. Oliveira  Willian K. Oliveira  Carla Andrade  Antonio Diego B. Melo  Fernando B. Luciano  Renata E. F. Macedo  Leandro B. Costa 《Journal of animal physiology and animal nutrition》2019,103(3):756-765

This study evaluated the antimicrobial effect of essential oils (EO) and organic acids (OA) against Salmonella Enteritidis in chicken feed and during an in vitro model that mimics the chicken digestive process. The minimal inhibitory concentration (MIC) of allyl isothiocyanate (AITC), carvacrol (CV), propionic acid (PROP) and caproic acid (CAP) were individually determined. Then, based on the MICs of each compound, combinations of EOs and/or OAs were tested to evaluate their synergic antimicrobial effect. The synergic effect of AITC and CAP was the most efficient against the bacterial strain tested. Commercial feed was inoculated with a 5‐strain cocktail of S. Enteritidis and treated with different doses of AITC + CAP to evaluate their effect on the growth/survival of the pathogen. In addition, the simulated digestion model was used to access the antimicrobial effect of AITC + CAP added to the feed towards S. Enteritidis and Lactobacillus plantarum. Synergistic effect was found between AITC (0.065 mM) and CAP (17.5 mM) against S. Enteritidis in chicken feed, where S. Enteritidis was reduced to undetectable levels (<1.00 log CFU/g). AITC (1.95 mM) + CAP (45 mM) also decreased (p < 0.05) the population of S. Enteritidis in the simulated digestion, while the growth of L. plantarum was not affected. Therefore, the addition of AITC + CAP in feed might be a potential natural antimicrobial able to prevent economic losses caused for Salmonella in chicken.  相似文献   

Prevalence of lameness and hoof lesions in all year-round grazing cattle in Brazil     

Tiago Facury Moreira  Rafael Romero Nicolino  Leandro Silva de Andrade  Elias Jorge Facury Filho  Antônio Ultimo de Carvalho 《Tropical animal health and production》2018,50(8):1829-1834

Lameness is a growing concern to the dairy industry worldwide. However, little is known about lameness and its causes in grazing cattle, especially in tropical climates. This study aimed to assess the prevalence of hoof lesions and lameness in dairy herds of all year-round grazing cattle under tropical condition, and to identify the main lesions associated with lameness. We visited 48 farms located in the Minas Gerais state, Brazil, equally divided into four groups based on daily milk production. All lactating cows in the visited farms were locomotion scored, and a representative sample was randomly chosen for hoof inspection. Among the 2267 lactating cows evaluated, 16% were scored as lame and 7% as severely lame. Nearly all cows presented at least one type of hoof lesion, of which heel horn erosion (90%), white line fissure (50%), and digital dermatitis (33%) were the most prevalent. Heel horn erosion was present in all farms and digital dermatitis was present in 96% of the farms. Sole ulcer was observed in a single animal. Additionally, digital dermatitis and white line fissure were correlated to a 2.5 times increase in the odds of a poor mobility score. Collectively, our results demonstrate that digital dermatitis and white line fissure are the main concern and the biggest cause of lameness in grazing cattle under tropical conditions.  相似文献   

Soybean grain is a suitable replacement with soybean meal in multiple supplements for Nellore heifers grazing tropical pastures     

Daniel Mageste de Almeida  Marcos Inácio Marcondes  Luciana Navajas Rennó  Leandro Soares Martins  Faider Alberto Castaño Villadiego  Mário Fonseca Paulino 《Tropical animal health and production》2018,50(8):1843-1849

The research aimed to evaluate the effect of replacing soybean meal with soybean grain on the nutritional parameters and productivity of heifers grazing on Urochloa decumbens in the rainy-dry transition period. Forty crossbred heifers with the initial age and weight of 18 months and 292?±?6.1 kg, respectively, were used. The experimental design was a completely randomized design, with five treatments and eight replications. The evaluated treatments were as follows: SM_0.5—supply of 0.5 kg/animal/day of soybean meal supplement; SG_0.5—supply of 0.5 kg/animal/day of soybean grain supplement; SM_1.0—supply of 1.0 kg/animal/day of soybean meal supplement; SG_1.0—supply of 1.0 kg/animal/day of soybean grain supplement; MM—only mineral mix ad libitum. The supplement was isoprotein with 350 g of crude protein/kg of dry matter. Supplementation improved the performance of the heifers and this fact can be verified by the higher average daily gain (ADG) and final BW (fBW) of the supplemented animals (P?<?0.10). The two supplemented treatments with 1 kg/day demonstrated similar performance (P?>?0.10), the same happens for the two treatments receiving 0.5 kg/day (P?>?0.10). However, animals receiving 1 kg/day of supplementation had an ADG and final BW higher than animals receiving 0.5 kg/day (P?<?0.10). Supplementation (P?<?0.10) affected the intake of dry matter (DM), organic matter, crude protein, ether extract, non-fiber carbohydrates, total digestible nutrients, and neutral detergent fiber corrected for ash and protein (apNDF). Supplementation improved DM digestibility and all constituents of the diet (P?<?0.10), except for apNDF (P?>?0.10). In summary, it is concluded that multiple supplementations improve the performance of grazing heifers in the rainy-dry transition period and the total replacement of soybean meal by soybean grain does not alter the performance of the animals.  相似文献