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The control of the impact of diseases on plants can be carried out via breeding, through the development of cultivars less susceptible to pathogens. Therefore, this study aimed to assess the severity of fungal diseases in upland rice strains from the Cultivation and Use Value test, belonging to the Upland Rice Breeding Program” of Federal University of Lavras (UFLA), in partnership with “EMBRAPA Rice and Beans” and the “Minas Gerais Agricultural Research Company” (EPAMIG). The experiment was installed in the municipalities of Lambari and Lavras, both in Minas Gerais, Brasil, in the 2015/2016 and 2016/2017 seasons, in a randomized block design with three replications. Were evaluated 14 lines, 11 lines of the program and 3 commercial witnesses, regarding the intensity of diseases (leaf and neck blast, brown spot, grain spot and scalding). There was a significant difference between lineages for all traits, except brown spot, indicating the presence of genetic variability for the characters in question. The study of the interaction was performed, decomposing the statistically significant ones in simple and complex interactions. The experiment presented a coefficient of variation from 29% to 56% and accuracy from 56% to 95.5%, indicating that the estimates were obtained with good to medium experimental precision. It is essential to evaluate diseases in breeding programs in order to select cultivars that are increasingly resistant, as these affect not only productivity, but the quality and final yield of grains. The genotypes CMG 2119 (5), CMG 2162 (1), CMG 1896 (13) and CMG 2168 (2) were shown to be more tolerant to all diseases simultaneously, being, therefore, the most suitable for the launch, considering the character disease resistance. The Upland Rice Breeding Program of UFLA has lines with variability for resistance, strains with potential for release.

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.

Insects of the genus Sitophilus are among the most destructive pests in rice storage, and the best strategy to control it is to use resistant genotypes. In this study, 26 upland rice elite lines were evaluated for Sitophilus weevil reaction on grain weight. The seeds were placed in plastic recipients stored in a room with temperature and lightning simulating a warehouse environment. The number of living weevils and the grain weight were obtained in two evaluations, one 35 days after storage, and the other 35 days after infestation. The lines differed statistically for number of living weevils and for grain weight in both evaluations. The correlations between these two characters were - 0.99 and - 0.47 for the first and the second evaluation (P < 0.05), respectively. The lines BRS Pepita, AB 112089 and AB 112090 were the most susceptible. Seventeen of the twenty-six elite lines were resistant in both evaluations and could be successfully used in upland rice breeding programs.

The aim of the present study was to determine the dose of Nitrogen and plant spacing of BRSMG Caravera, a modern rice cultivar, in order to maximize grain yield and increase rice production in the state of Minas Gerais, Brazil. The following characteristics were evaluated: grain yield (GY), percentage of filled grains (% F), 100 grains weight (100 GW) and plant height (H). It was used a 4 × 4 factorial design, with four row spacings (20, 30, 40 and 50 cm) and four nitrogen rates (0, 40, 80 and 120 kg ha-1) totaling 16 treatments. The phenotypes were analyzed through the Scott-Knott mean test together with an analysis for significant interactions to identify the spacing and the N rates associated with the best trait averages. Differences in plant spacing were associated with significant differences in GY, % F and H, whereas different N rates were associated with significant differences of GY and H. When considering the interaction between plant spacing and N rates, significant differences could be identified for all traits, indicating that these factors should be considered together. The highest grain yield was achieved with spacing of 20 cm and N rate of 120 kg ha-1. The use of modern cultivars, the adequate spacing and N dose can significantly increase grain yield and competitiveness of upland rice cultivation, in the state of Minas Gerais, Brazil.