Rosa Lia Barbieri

Resistência das plantas a moléstias fúngicas

Plant resistance to fungic diseases is due to their genetic constitution and environmental factors. In breeding programs, one of the main objectives is to obtain high grainyield potenlial plants with resistance to the prevalent diseases. Knowledge of genetic basis of resistance is importam to increase selection efficiency and due to the wide variability of fungi there is the necessity of using different strategies to reduce the probability of pathogen estabtishment in crops.

Origin, Domestication, and Dispersing of Pear (Pyrus spp.)

The pear (Pyrus communis L.) is a typical fruit of temperate regions, having its origin and domestication at two different points, China and Asia Minor until the Middle East. It is the fifth most widely produced fruit in the world, being produced mainly in China, Europe, and the United States. Pear belongs to rosaceous family, being a close “cousin” of the apple, but with some particularities that make this fruit special with a delicate flavor. Thus, it deserves a special attention and a meticulous review of all the history involved, and the recent research devoted to it, because of the economic and cultural importance of this fruit in a range of countries and cultures. Therefore, the purpose of this literature review is to approach the history of the origin, domestication, and dispersal of pears, as well as reporting their botany, their current scenario in the world, and their breeding and conservation.

Medicinal plants: knowledge transmission in families of ecological farmers in souther Rio Grande do Sul

O objetivo deste estudo foi investigar o processo de transmissao do conhecimento relacionado as plantas medicinais entre as geracoes familiares, no contexto de agricultores de base ecologica da regiao sul do Rio Grande do Sul. Trata-se de um estudo qualitativo realizado com oito familias de agricultores, totalizando 19 entrevistados, residentes nos municipios de Pelotas, Morro Redondo, Cangucu e Arroio do Padre, entre janeiro e maio de 2009. A analise dos dados foi realizada atraves do metodo hermeneutico-dialetico. A familia foi referida como a principal fonte na transmissao do conhecimento em relacao as plantas medicinais. A maioria dos sujeitos informou primeiro realizar o tratamento com as plantas medicinais para em seguida buscar o servico formal de saude. A construcao do conhecimento relacionado as plantas medicinais pelas familias e predominantemente oral, realizada atraves do convivio diario entre seus membros e compartilhada com os demais membros da comunidade na qual estao inseridos.The aim of this study was to investigate the process of knowledge transmission related to medicinal plants among family generations in the context of ecological farmers in Southern Rio Grande do Sul. This qualitative study was conducted with eight farming families, comprising 19 respondents living in the municipalities of Pelotas, Morro Redondo, Canguçu and Arroio do Padre. The interviews took place from January to May 2009. Data analysis was performed using the hermeneutic-dialectic method. The family was referred to as the main source in the transmission of knowledge about medicinal plants. Most subjects reported first completing treatment with medicinal plants, to then seek formal health service. The construction of knowledge related to medicinal plants by the families is predominantly oral, and takes place by the daily contact between its members and is shared with other members of the community to which they belong.

Caracteres relacionados com a resistência ao acamamento em trigo comum

Grain yield is affected by plant lodging, and this is a serious problem mainly for tall wheat cultivars. A field trial was conducted during 1999 growing season to investigate the variability for some morphological traits associated to lodging resistance in 14 wheat genotypes. It was found variability for all traits evaluated. Values of lodging resistance coefficient, plant height, length of peduncle and culm index were highly correlated with lodging resistance. These traits can be recommended for lodging resistance indirect selection. Among genotypes evaluated, line TB 951 showed the best performance for all traits related to lodging resistance. So, that line can be indicated as an excellent lodging resistance source in bread wheat.

Variabilidade genética para compostos antioxidantes em variedades crioulas de pimentas ( Capsicum baccatum )

Peppers have compounds that are beneficial to health, such as vitamins, flavonoids, carotenoids and other secondary metabolites with antioxidant properties. This study aimed to evaluate the genetic variability for antioxidant activity and concentration of antioxidant compounds in landraces of Capsicum baccatum grown in Brazil, besides estimating the correlation between the evaluated parameters. The antioxidant activity and concentration of total phenolics, total anthocyanins and carotenoids were evaluated in 24 landraces of C. baccatum from Capsicum Gene Bank of Embrapa Temperate Agriculture. The results showed genetic variability for all variables. The analysis of carotenoids showed the highest number of groups by Scott-Knott test, with seven established groups. Accessions P62, P85 and P108, with a high concentration of phenolic compounds, P13, P15 and P61, with high antioxidant activity, P68, with higher content of anthocyanins, and P179, with high production of carotenoids, are good sources of natural antioxidants compounds. Correlations between the antioxidant compounds ranged from low to moderate. No relationship between shape, color and pungency of fruits and the content of antioxidant compounds evaluated was found in landraces of pepper.

Avaliação do óleo essencial de Aloysia sellowii (Briquet) moldenke (Verbenaceae) do Sul do Brasil

This work was performed with the aim of evaluating the chemical variability among samples of Aloysia sellowii (Verbenaceae) collected in different geographical regions as well as the application of supercritical CO2 for obtaining essential oil. Thus, samples were collected in different localities and oils were isolated by hydrodistillation and supercritical CO2. Results showed existence of two chimiotypes in the species (cineole and sabinene). The supercritical CO2 extraction process was appropriate for extraction of A. sellowii essential oil at 40 oC, 110 bar, 2 mL/min of flow and 10 min of extraction time.

Utilização do inseticida Methomyl na seleção de genótipos de aveia resistentes à helmintosporiose

Spot Blotch is a plant disease which causes yield losses in oat and other cereals. Selection for resistant genotypes using Helminthosporium sativum toxic filtrates is an efficient technique, which reduces the pathogen variability and the influence of the environment over the genotype expression. The filtrates extraction is time consuming and a difficult process, and the possibility of using a synthetic product to simulate its action of inhibiting the cell electron transport chain would be useful. The Methomyl insecticide is an efficient product to simulate the effects of the fungus that causes spot blotch in corn. The objective of this study was to check its efficiency in oat. Oat roots and callus growth were evaluated in the insecticide presence. Growth values that were less inhibited by the insecticide were used to correlate with spot blotch resistance. The results indicate that Methomyl reduces the growth of oat root and calli and may be used to differentiate genotypes more and less resistant to Spot Blotch. Therefore, UFRGS 14, which was the most affected genotype in the presence of the fungus toxic filtrates, had also the most reduced root and calli growth in the presence of Methomyl.

Genetics of resistance to the fungus Helminthosporium sativum in wheat: use of culture filtrates in tissue culture

Six wheat genotypes and their F1 and F2 generations were exposed to the action of Helminthosporium sativum culture filtrates to examine the genetics of hexaploid wheat resistance. The objective was to improve the efficiency of breeding programs by identifying the action and number of genes involved in the resistance. The varied response of the tested genotypes to the culture filtrates allowed division of the genotypes into four groups: resistant, moderately resistant, moderately susceptible and susceptible. This variability was detected in the progeny, suggesting that the parents have distinct genetic constitutions. Additive gene action predominated and genetic gain was shown to be possible through selection. The genetic control of the resistance trait seems to be complex because of the presence of gene interaction and the difficulty of eliminating the environmental effects. The inheritance seems to be oligogenic

Effect of in vitro digestion on functional properties of Psidium cattleianum Sabine (araçá), Butia odorata (Barb. Rodr.) Noblick (butiá) and Eugenia uniflora L. (pitanga) fruit extracts

Brazilian native fruits are reported to be promising sources of bioactive compounds; however their bioactivity depends on their stability along the digestive process. This study evaluated the α-glucosidase inhibition, antioxidant activity and total phenolic content (TPC) stability of araçá, butiá and pitanga fruit extracts using an in vitro digestion model. Additionally, the individual phenolic compound recovery of the most stable and active extract was evaluated by HPLC-DAD-ESI-MS/MS. Overall, the antioxidant activity of all extracts decreased along the process. Araçá fruit extracts, at the end of digestion, showed α-glucosidase inhibition values similar to their non-digested extracts and the highest TPC recovery (28%). Recovery of individual phenolic compounds of red araçá fruit extract revealed a negative impact on the stability of ellagitannins. Araçá fruit extract seems to provide phenolic compounds with α-glucosidase inhibitory properties after the gastrointestinal digestion, indicating their potential to be used in the control of type II diabetes.

Vase life of roses, gerberas and chrysanthemums commercialized in Pelotas-RS

Cut flowers are one of the most important floricultural products and one of the features that define its quality is vase life. Thus, longer vase life will be achieved when production sites are closer to the consumer market. Based on the above, this experiment compared vase life of rose, gerbera and chrysanthemums supplied by Pelotas’s local growers and by Sao Paulo’s wholesalers. For each treatment (origin), 20 stems of each species were evaluated. Randomized block design were used with five repetitions of four stems per block and vase life assessment performed every three days during 15 days. Vase life was higher for roses and gerberas produced in Pelotas, average of 9 and 7 days, respectively. No significant difference was observed to chrysanthemum vase life, average were 12 days for both flower origins. The results indicate that the distance between the production sites and the consumer market influences the quality and vase life of roses and gerberas marketed in Pelotas