A alternativa adotada nos programas de melhoramento genético para diminuir o efeito da interação genótipo x ambiente (G x A), é através da avaliação das linhagens em uma rede de experimentos, sendo esses, conduzidos em vários anos e ambientes representativos das regiões edafoclimáticas de cultivo. Diante disso, o objetivo desse trabalho foi avaliar a adaptabilidade e estabilidade produtiva de genótipos de arroz de terras altas no estado de Minas Gerais, utilizando a ferramenta gráfica para análise de dados, o GGE biplot. Foram utilizados dados de produtividade de grãos, provenientes da avaliação de vinte linhagens de arroz do ensaio de Valor de Cultivo e Uso do programa de melhoramento de arroz de terras altas da Universidade Federal de Lavras em parceria com a Embrapa e Epamig. Os ensaios foram conduzidos em delineamento de blocos completos, com três repetições nas safras de 2013/2014, 2014/2015 e 2015/2016. Os experimentos foram conduzidos em um total de nove locais divididos dentro das três safras nas cidades de Lambari, Lavras e Patos de Minas, todas localizadas no estado de Minas Gerais. Concluiu-se com este trabalho que as linhagens foram em quase sua totalidade mais adaptadas e estáveis que as cultivares comerciais. Os genótipos 10 e 13 foram superiores à média geral para produtividade e apresentaram alta estabilidade, sendo candidatos futuros para lançamento como novas cultivares.

This study aimed to verify the efficiency of multilines in reducing blast progress and their potential benefits to phenotypic stability in rice. The experiments were conducted in the 2016/17 and 2017/18 agricultural years. A randomized block design was performed with three replications, evaluating 12 lines and a multiline, which consisted of five lines from the Cultivation and Use Value (CUV) test. The multiline presented an estimated grain yield above the average of experiments of around seven bags ha-1 and superior performance in early flowering, justifying the high phenotypic stability for these characters. In this case, the line selection for composing the multiline was favorable and efficient, highlighted by a higher agronomic performance than most lines of the CUV test. The multiline is an adequate strategy to provide higher phenotypic stability and reduce blast progress in the field.

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To assist in upland rice breeding programs, estimated genetic and phenotypic parameters are extremely important in the selection of superior lines. Thus, the objective of this study was estimate the genetic and phenotypic parameters of upland rice lines of the breeding program of UFLA in partnership with Embrapa Arroz e Feijão and Epamig. The experiment was installed in an experimental area of the Department of Agriculture at UFLA. It was evaluated 36 upland rice lines of the preliminary trial of the 2014/15 season, in randomized blocks, with three replications and plots consisted of five rows and each row has four meters. For this, it was evaluated the characters: plant height (cm), yield (kg•ha −1 ), 100-grain weight, days until flowering, percentage of filled grains and rice blast severity. The variance analysis and genetic parameters were estimated using the software SAS. To evaluate the experimental precision was estimated the accuracy, which varied between 63% and 98%, showing experimental precision, moderate to high. The lines differed significantly for all characters, meaning there is genetic variability among genotypes evaluated. With intensity of selection of 10% of lines, it was obtained a genetic gain of 325.29 kg•ha −1 in the character productivity, a plant height (cm) reduction in 5.50 cm, and days until flowering, with a reduction of 9.23 days, with selection of earlier plants. The estimated values for heritability ranged from 38% -96%. Estimates confirm the possible success with the selection of the upland rice lines for these characters.

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