RAPD optimization for genetic studies with Citrulus lanatus and Sesamum indicum genotypes

The Random Amplified Polymorphic DNA (RAPD) technique is powerful for DNA polymorphism determinations and is widely used in research involving different organisms, but it is known that RAPD can be affected by many factors that may result in false positive bands and non-reproducible assays. In this study, we analyzed the effect of several factors such as DNA template, primer and Taq DNA polymerase concentrations to optimize and standardize the RAPD technique for further genetic studies with Citrulus lanattus and Sesamum indicum L. The best combination of DNA, Taq DNA polymerase enzyme and primer concentrations in RAPD amplification procedures for sesame and watermelon genotypes was established.

Preliminary selection of acerola genotypes in Brazil

Introduction. Breeding studies for acerola (Malpighia glabra) improvement aim at obtaining plants that produce fruits with uniform chemical and physical attributes, including high levels of vitamin C, which can provision the market with fresh fruit and frozen pulp. High variability in fruit quality is observed in Brazilian acerola crops, especially those propagated by seeds. In this context, the objective of our research was to evaluate the physical and chemical characteristics of Brazilian acerola genotype fruits. Materials and methods. Sixteen acerola genotypes were studied in Jaboticabal, São Paulo State, Brazil. A completely randomized design with sixteen treatments and six replications was adopted. Each treatment was represented by one genotype. Several parameters related to fruit quality, such as width, length, weight, pulp percentage, soluble solids (SS), titratable acidity (TA), [SS / TA] ratio and vitamin C content, were evaluated in fruits of the acerola genotypes. The results were submitted to variance analyses, the Tukey test and cluster analysis. Results and discussion. There was a statistical difference between the acerola genotypes studied. Three of them stood out as natural sources of vitamin C. In spite of fruit size, two acerola genotypes were found to have potential for fresh fruit production. In a general form, genotypes that presented a high [SS / TA] ratio had low vitamin C content. Conclusion. The acerola genotypes studied in Jaboticabal presented high variability, forming eleven groups in relation to fruit quality parameters. © 2007 Cirad/EDP Sciences All rights reserved.

Determination of crude protein, crude fiber and crude fat in twenty-five genotypes of kale (B. oleracea var. acephala)

The aim of the study was to determine the percentage of crude protein, crude fiber and crude fat (ether extract) of 25 genotypes of kale from the Germplasm Bank of Instituto Agronômico de Campinas and of one genotype grown in the region of Jaboticabal-SP. The plants were cultivated in the field, and the leaves after collection were pre-dried in a convection oven at 65°C for 72 h. Afterward, the leaves were analyzed for crude protein, crude fiber and crude fat (ether-soluble materials). Significant differences were detected among the different genotypes for all the characteristics examined. Of the genotypes studied, six showed more than 30% crude protein: HS-20 (32.56%), Comum (31.70%), Couve de Arthur Nogueira 2 (31.16%), Pires 2 de Campinas (30.63%), Manteiga I-916 (30.36%), and Manteiga de Ribeirao Pires I-2446 (30.03%). In relation to crude fiber, the highest percentage was seen in the genotype Manteiga de Mococa (10.92%), differing significantly from the other genotypes studied. With regard to crude fat, the highest percentage was found in the genotype HS-20 (3.72%), and Pires 1 de Campinas (3.34%). Of the genotypes tested, HS-20 stood out among the others, showing both the highest percentage of protein and fat.

Performance of different genotypes of vegetable soybeans in Jaboticabal-SP

The study was conducted in the field, in the experimental area of the Section of Crop Production and Aromatic Medicinal Plants, belonging to the Faculty of Agricultural and Veterinary Sciences, Jaboticabal Campus-SP. The aim of the study was to assess the performance of seven genotypes of vegetable soybeans in Jaboticabal-SP. The experiment was carried out in a complete randomized block design with seven treatments (genotypes) and four replications. The genotypes examined were: CNPSOI, JLM003, JLM010, JLM018, JLM019, JLM024 and BRS216. The seeds were obtained from EMBRAPA-Soja and EMBRAPA- Hortaliças, and planted in Styrofoam trays with 128 cells containing Plantmax Hortaliças® as substrate. Transplanting occurred 10 d after seeding when the seedlings showed 2 or 3 definitive leaves and about 12 cm in height, demonstrating that the soil had been properly prepared according to the recommendations for this crop. Pests and diseases were adequately controlled in the event of their occurrence in the experimental area and in accordance with technical recommendations for the chemical products utilized. Collections were carried out based on the maturation of the pods, according to the scale of Fehr and Caviness (1977) adapted by Costa and Marchezan (1982), when the pods reached the reproductive stage R6. The parameters determined were mean precocity, height of the first pod, mean number of pods per plant, mean number of seeds per pod, fresh weight of 100 seeds and total yield of immature grains. Based on the results obtained, the genotypes JLM003 and JLM010 were found to be most indicated for growing vegetable soybeans, because of their capacity to produce immature grains of 1090 and 848 g·m-2, respectively, and fresh weights for 100 seeds of 62.20 and 68.19 g, respectively.

Competition policies in emerging economies: lessons and challenges from Central America and Mexico

Incluye Bibliografía

Models of privatization and development of competition in telecommunications in Central America and Mexico

Incluye Bibliografía

Competition and regulation in the banking system of Central America and Mexico: a comparative study

Incluye Bibliografía

Advantages and limitations of Costa Rica's experience in competition policy. A benchmark for the rest of the countries in the Central American region

Incluye Bibliografía

Banking competition in Mexico

Incluye Bibliografía

Cooperation on competition policy in Latin American and Caribbean bilateral trade agreements

Incluye Bibliografía

Legal and economic interfaces between antidumping and competition policy

Includes bibliography

Multilateral rules on competition policy: an overview of the debate

Includes bibliography

Policy competition for foreign direct investment in the Caribbean Basin: Costa Rica, the Dominican Republic and Jamaica

Includes bibliography

The effectiveness of technical assistance, socio-economic development and the absorptive capacity of competition authorities

Includes bibliography

Best practices in defence of competition in Argentina and Brazil: useful aspects for Central America

Includes bibliography