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One of the main obstacles for food production in many developing countries, as in Brazil, is the damage caused by root-knot nematodes, mainly those belonging to the genus Meloidogyne. This study aimed to assess the resistance levels of 44 sweet potato genotypes to M. javanica, M. incognita race 1 and M. enterolobii. These researches were carried out in 2014, under greenhouse conditions in Brasília-DF, Brazil. A completely randomized design with six replicates of one plant/plot/treatment was used. We determined the gall index (GI) and egg mass index (EMI) in the root system of each plant, the number of eggs and juveniles per gram of root with galls and the nematode reproduction factor. M. javanica was less aggressive and reproduced in only 9.09% of the evaluated genotypes; M. incognita race 1 was intermediate (47.73%); whereas M. enterolobii was more aggressive, with a population increase in 79.55% of the genotypes. The genotypes CNPH 1200, CNPH 1219, CNPH 1292, CNPH 1392, CNPH 60 and ‘Coquinho’ were the most resistant to the three species and can be used in breeding programs for multiple resistance to root-knot nematodes. RESUMO Um dos principais obstáculos para a produção de alimentos em muitos países em desenvolvimento, como no Brasil, é o dano causado por fitonematoides, principalmente os formadores de galhas, pertencentes ao gênero Meloidogyne. O trabalho teve como objetivo avaliar o nível de resistência de 44 genótipos de batata-doce a M. javanica, M. incognita raça 1 e M. enterolobii. O experimento foi realizado em 2014, em casa de vegetação, em Brasília-DF. Utilizou-se o delineamento inteiramente casualizado, com seis repetições, constituindo-se de uma planta por tratamento. Foi determinado o índice de galhas (GI) e de massas de ovos (EMI) no sistema radicular de cada planta, quantificado o número de ovos e juvenis por grama de raiz e parte da raiz tuberosa com galhas e efetuado o cálculo do fator de reprodução dos nematoides. Verificou-se que M. javanica foi menos agressivo e se reproduziu em apenas 9,09% dos genótipos avaliados. M. incognita raça 1 foi intermediário, com 47,73%; enquanto que M. enterolobii foi mais agressivo, com aumento populacional em 79,55% dos genótipos. Os genótipos CNPH 1200, CNPH 1219, CNPH 1292, CNPH 1392, CNPH 60 e ‘Coquinho’ foram os mais resistentes às três espécies avaliadas, podendo ser utilizados no melhoramento visando à resistência múltipla aos nematoides-das-galhas.

Carotenoids were extracted from pressed palm fiber using supercritical CO2 and microencapsulated by spray-drying with gum Arabic. Twenty-eight tests were made. Emulsions were characterized with respect to droplet size and viscosity. The effects of solid content and spray-drying conditions on moisture, hygroscopicity, microencapsulation efficiency, and powder lipid oxidation were investigated. Particles produced at optimized process (35% of solids, feed flow of 26%, temperature of 166 °C, and atomization air flow of 40 mm) were evaluated for major carotenoids identification and fatty acid profile. Higher solid content led to higher encapsulation efficiency and lower lipid oxidation, which was related to the higher emulsion viscosity and lower droplet size. Increasing atomization air flow and temperature resulted in higher lipid oxidation. Moisture increased and higroscopicity decreased when higher feed flow and lower temperature were used. Microparticles presented high content of monounsaturated fatty acids, α-, β-, and (9Z)-β-carotene and reflected the composition of un-encapsulated oil.

American oil palm [Elaeis oleifera (Kunth) Cortes] is known to present a much slower palm oil deterioration rate than African oil palm (E. guineensis Jacq.). In the present study, fatty acid composition, total carotenoids, oil content, and free fatty acid content were characterized for five accessions (Careiro, Anori, Manicoré, Coari, and Autazes) belonging to an American oil palm collection maintained as field gene bank by Embrapa. This germplasm collection was originally collected in different areas in the Brazilian Amazon forest. These accessions were subjected to different storage times (1, 7, and 14 d) before processing to evaluate the quality of the oil produced. Oil content of the dried pulp was found to range between 31.36 and 50.34%. Gas chromatographic analysis revealed that oleic acid is the predominant monounsaturated fatty acid in all five accessions. After 14 d of fruit storage, these accessions were found to maintain low acidity (free fatty acid content), between 1.33 and 2.66%. Total carotenoid content was presented in high concentrations in all five accessions (>1500 mg kg−1). The estimation of genetic parameters showed, in general, high heritability values (>80%), and the estimated genetic gains were generally very high. Coari and Careiro presented the highest oil yields, whereas Manicoré and Coari presented the lowest acidity. These two characteristics are the most important ones when selecting the best parental donor to develop superior interspecific hybrids. Made available in DSpace on 2021-04-19T17:34:13Z (GMT). No. of bitstreams: 1 cs-58-5-19821.pdf: 2157614 bytes, checksum: de927d97b43fc2ae06723da962ec95ac (MD5) Previous issue date: 2018