14 research outputs found
Heterogeneity of linalool chemotypes of Lippia alba (Mill.) N.E.Br., based on clonal half-sib progenies
Lippia alba (Mill.) N.E.Br. is an aromatic and medicinal shrub native to the American continent. Despite its potential as a source of essential oil for the pharmaceutical and cosmetics industries, few selection and genetic improvement studies have been carried out. The aim of this study was to provide genetic information on this species for breeding programs, showing its selection potential, by investigating clonal half-sib progenies. The following characteristics were evaluated per plant: leaf dry mass (LDM), total dry mass (TDM), leaf yield (LY), essential oil yield (EOY) and oil production (OP). Estimates were made for the several genetic parameters including absolute genetic gain at 30% selection intensity, correlations and relative contribution of additive and environmental effects to phenotypic correlation. Two experimental trials on 30 progenies were conducted: one in Campinas, state of São Paulo (SP), Brazil, with two harvests of the aerial part, and one in Monte Alegre do Sul, SP, Brazil, with only one harvest. The trials were conducted in a randomized block design consisting of subplots with three replications, each plot (progeny) consisting of 8 to 15 clonally-replicated plants with subplot harvesting. Variations were detected between progenies and harvests, as well as progeny/harvest interactions in the split plot experiment. High heritability and genetic gains were obtained at both sites for LDM, TDM and OP. The lowest variations among progenies were obtained for LY and EOY, highlighting selection problems. Negative additive genetic correlations were obtained for EOY × LDM, EOY × TDM, LY × TDM and LY × LDM. Selection for LDM resulted in increased oil production per plant (OP), even where there was a negative correlation between LDM × EOY
SEMINARS ON BIOCHEMISTRY: IS AN EFFECTIVE METHODOLOGY IN THE PROCESS LEARNING/TEACHING?
Introduction in Biochemistry is a discipline held by the Department of Biochemistry and Molecular Biology at UFC. It is offered to the students of the Sciences Centers. The majority of the classes employs as pedagogical tools,theoretical lectures and problem solving activities. To avoid that the learning process is restricted to memorizing, it was elaborated a learning project aiming a better comprehension of the explored content. The methodology included seminars given by the students on subjects analyzed on previous classes.These students were divided in two groups of ten members and each group was assigned to topics of carbohydrates metabolism with the approach on applied Biochemistry. After presentations, a survey was applied revealing that students approved this methodology. The reason given was a better perception of fundamental Biochemistry and its application to their professional field. The evaluation of this methodology was also done based on the grades and it was as follows: in the first evaluation before the seminars, the average score was 4.7 and after, in the second evaluation involving the seminars, the average increased to 7.18. The third and last evaluation without seminars, it was observed a reduction of the average score to 5.63. These results suggest that seminars on Biochemistry were an effective pedagogical methodology in the process of learning/teaching
