Search

The correlation estimation and its partition into cause and effect is seen as a valuable tool in obtaining gains from selection in plant breeding. This allows the anticipation of choosing the best genotypes. Thus, the objective of this study was to consider indirect selection for simultaneous improvement of root and aboveground traits in segregating common bean populations. The experiment was carried out in the 2021/22 season, considering six common bean genotypes, two parents and four segregating generations (F2, F3, F4 and F5), under a lattice design. Root system traits were measured by two phenotyping methods, called Shovelomics and WinRHIZO. The aerial part traits evaluated were chlorophyll content, plant height, stem diameter, first pod height insertion and yield components (number of pods, number of grains and weight of grains per plant). Correlation analysis and cause and effect analysis (path analysis) were performed. Significant correlation estimates (t) were found between root and aerial traits, with emphasis on chlorophyll B content with left horizontal length (t = -0.22) and chlorophyll A content with total root length (t = 0.24). The unfolding of these estimates by path analysis indicated that the chlorophyll A content has a correlation and a high direct effect on the total length of roots and that the total chlorophyll content indirectly influences the left and right horizontal root lengths. This fact makes it possible to obtain gains with the selection of improved common bean plants for root system based on the direct and indirect evaluation of chlorophyll contents, easily measured in the aerial part of the plants. This allows the optimization of time and resources in breeding programs, aiming at obtaining agronomically superior plants. [ABSTRACT FROM AUTHOR]

Routine evaluations of cooking time trait in common bean (Phaseolus vulgaris L.) can be performed in different ways resulting in different variables. At the same time, the univariate statistical analysis does not consider the interdependencies between the variables, and may omit important information regarding the genotypes. With this, the objective of this work was to present an alternative proposal for analysis of the cooking time in common bean, allowing the discrimination between genotypes. The experiment used for this approach was conducted under field conditions in the 2017/18 agricultural season in Lages, Santa Catarina, Brazil. The treatments consisted of twelve genotypes, (four parents, structured in two crossings BAF50 x BAF07 and BAF09 x IPR 88 Uirapuru, with their generations F2, F3, F8 and F9). The design used was randomized blocks, with two blocks and two observations in each experimental unit. After the harvest, the response variable cooking time of the grains was measured with a Mattson cooker, considering the cooking time of the 13 initial stems. In the multivariate analysis, the variables cooking time of the second (TCH2), twelfth (TCH12) and thirteenth stem (TCH13) were used based on their significance by the stepwise variable selection method. Multivariate analysis of variance showed differences between genotypes (P<0.05). From the dissimilarity matrix with the Mahalanobis distances and the clustering dendrogram, it was possible to verify the distances of the genotypes derived from crosses BAF50 x BAF07 and BAF09 x IPR 88 Uirapuru. With that, the multivariate analysis enabled the genotypes, additionally the crossing BAF50 x BAF07 showed higher estimates of dissimilarity in the progenies. [ABSTRACT FROM AUTHOR]

The quality of the seed directly impacts the agronomic characteristics and the final yield of the soybean crop. Therefore, the objective of the study was to evaluate different phytotechnical parameters and the final productivity for different soybean cultivars obtained in a certified way and saved by the rural producer. The study was carried out in the Experimental Area of the University of Cruz Alta. During the 2017/2018 harvest, the plant breeding parameters were evaluated: plant height, stem diameter, number of branches, number of pods, lodging and final yield for cultivars NA5909RG, NS5959IPRO, NS5445IPRO and NS6909IPRO under different ways of obtaining, being these, "saved seeds" and "certified seeds". The phytotechnical parameters evaluated were influenced by the way of obtaining the seed for cultivars NS5445IPRO and NS6909IPRO. Among the evaluated cultivars, it was found that the yield of NS5445IPRO and NS6909IPRO were higher in plants from certified seeds. [ABSTRACT FROM AUTHOR]