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Spatial variation is a recurrent issue in field trials and can cause obstacles in terms of genetic selection. Analyses that account for spatial variation within location can lead breeders to predict genetic values accurately across locations in multi-environment trials (METs). The present study aims to fit spatial models for analyzing soybean [Glycine max (L.) Merr.] seed composition traits using a two-stage analysis pipeline and to assess its efficiency relative to a single-stage analysis setting. Seed protein content (SPC), seed oil content (SOC), and seed storage protein content (SSP) data were collected from 283 soybean genotypes tested in four environments (C1, C2, V1, and V2). In Stage 1 of the two-stage analysis, a randomized complete block (RCB) design model as well as four two-dimensional first-order (AR1 ⊗ AR1) spatial models were fit in each dataset to determine the most suitable model for genetic prediction. Predicted genetic values were used as input data for Stage 2. The most used spatial model [5] in Stage 1 of this study had accommodated local and global residuals. The autocorrelation estimates depicted spatial trends, especially in terms of rows, while column autocorrelation coefficients were low for C1 and C2 because of the limited number of blocks and their short length. Broad-sense heritability, mean accuracy, and selection gains were greater for all traits in the two-stage analysis than in the single-stage analysis. The two-stage analysis leveraged the spatial model fitting in the Stage 1 and proved to be advantageous for soybean seed composition breeding.

The objective was to evaluate the adaptability and yield stability of different peach rootstock genotypes in subtropical climate in an experiment in Chapecó, Santa Catarina, Brazil. Twenty-one rootstocks under the scion cultivar 'BRS Libra' and one genotype from self-rooted nursery trees were evaluated. The 22 genotypes were evaluated as fruit set and fruit yield in the growing seasons 2014/15, 2015/16, 2016/17 and 2017/18. Adaptability and stability were measured by the GGE biplot method. In the four years of evaluation, plants from self-rooted nursery trees had higher fruit set, yield as well as greater stability. On the other hand, the instability of plants grown on rootstocks from species other than the scion cultivar was greater. It can be concluded that under the tested conditions, the self-rooted genotype of 'BRS Libra' is a potential alternative for peach growers.

Hancornia speciosa Gomes is one of the native fruit species most frequent in the Brazilian Savanna. Studies on the genetic variability of quantitative traits for this species are scarce and the identification of accessions with the best agronomic traits may support strategies for conservation and breeding programs. This study aimed to estimate the genetic diversity of accessions from the H. speciosa germplasm collection of the Universidade Federal de Goiás (Goiânia, Goiás state, Brazil) and rank them based on a selection index combining eleven agronomic traits. A total of 192 individual accessions from 57 progenies, from 29 natural populations, were evaluated. The data were subjected to multivariate analysis and the individuals and progenies evaluated using the FAI-BLUP selection index. The Tocher cluster analysis allowed grouping the progenies into ten divergent clusters and the individuals into 18 divergent clusters. The simultaneous selection of traits based on the FAI-BLUP index may be recommended while maintaining the potential variability in the population resulting from the recombination. The individual selection proved to be more effective than the selection based on progenies means, because it exploits the genetic variation among and within progenies.

RESUMO No Brasil, existem poucos estudos sobre a epidemiologia da brusone do trigo, consequentemente, pouca informação tem sido gerada sobre o progresso da doença. Este estudo avaliou o progresso temporal da brusone do trigo em quatro genótipos, submetidos ao controle químico e a diferentes quantidades de inóculo primário de Pyricularia textomediograminis-triticitextomedio no campo. Os genótipos BRS 264, VI 98053, CD 116 e CD 104 foram inoculados com cinco volumes da suspensão fúngica (concentração de 1,5 x 105 esporos mL-1), de modo a obter, respectivamente, cinco porcentagens (0, 5, 10, 20 e 30 %) de plantas inoculadas na unidade experimental. A intensidade da brusone foi quantificada pela incidência e pela severidade da brusone em espigas e em folhas bandeira. As avaliações foram realizadas aos 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50 dias após a inoculação (DAI). As equações de regressão foram significativas e ajustadas ao modelo logístico. A aplicação de fungicida (piraclostrobina + epoxiconazol) retardou a manifestação dos sintomas da brusone nos genótipos e, quando combinado com a cultivar moderadamente resistente (CD 116), teve melhor eficiência na redução da doença. As cultivares BRS 264 e CD 104 apresentam maior incidência e severidade em espigas no tempo. Em geral, os genótipos apresentam baixa severidade da brusone em folhas bandeira (<0,45 %) e com um baixo progresso temporal, nas diferentes quantidades de inóculo de P. textomediograminis-triticitextomedio. Na região de Viçosa-MG, nas condições de inóculo artificial estudadas, a cultivar CD 116 se confirma como moderadamente resistente à brusone e os genótipos BRS 264, VI 98053 e CD 104 como suscetíveis.