Brazilian potato production is based on cultivars originating from the USA and Europe; however, these cultivars were developed under different environmental conditions than those found in Brazil. The aim of this study was to evaluate the adaptability and stability of 18 potato clones (MLG), developed by the Universidade Federal de Lavras, and four cultivars in six environments in the state of Minas Gerais, Brazil. The following traits were evaluated: marketable tuber yield (MTY), specific gravity (SG), and tuber appearance (TA). Clones, environments, and the genotype × environment interaction had significant effects on all traits. The 98.13, and 62.86 % of the sum of squares from the G+G×E for MTY, SG, and TA, respectively. Three MLG clones had higher adaptability and stability, as well as better performance, than the cultivars, making them good candidates for release as cultivars.

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Potato (Solanum tuberosum L.) is a cool weather crop and one of the most important vegetables in the world, which is cultivated in temperate, subtropical, and tropical climates. Nearly all cultivated areas in Brazil use cultivars from temperate countries, resulting in lower performances particularly due to higher temperatures. The aim of this study was to identify clones that yielded better than foreign cultivars, both under high and mild temperature conditions. The study assessed 57 clones from the potato breeding program of the Universidade Federal de Lavras (UFLA), Brazil, and five check cultivars (Agata, Asterix, Atlantic, Cupido, and Markies). We evaluated the agronomic performance using the total and marketable tuber yield, dry matter content (DM), season length, and external tuber quality, in four experiments designing in a random complete block, during the seasons 2014 and 2015. The genotypes' stability, as well as the discrimination between environments, was performed using the GGE-Biplot method. Twenty heat-tolerant clones responded favorably to mild temperatures. This breeding program has generated clones more productive and better looking than commercial cultivars, for the different market segments: two for the fresh market (GMR 17-40; GMR 12-10), four for frozen French fries (CBM 07-78; CTB 03-02; GMR 15-42; SR2 35-05) and seven for potato chips

Methodologies for imposing stress and reproducible results are a bottleneck for breeding programmes, and this is due to the lack of consensus between the existing methodologies. The aim of the present study was to propose and validate a new methodology for imposing water deficit in soybean that allows the identification of water deficit-tolerant genotypes, at different harvest times and phenological stages.The methodology was based on the construction of a water retention curve in the soil to determine the water stresses that indicate the field capacity and the permanent wilt point and, thus, define the water regime in the conditions of control and stress. Seven trials were carried out to validate the methodology. In trials 1, 2, 3, 4, 5 and 6, the water deficit was imposed in the reproductive phase and the components of production were evaluated. In addition to these variables, leaf water potential was evaluated in trial 6. In trial 7, the plants were subjected to water deficit in the vegetative phase and the morphological traits were evaluated. The efficiency of the methodology was confirmed by the distinction between the conditions of control and stress, affirmed by the statistical differences in most of the traits evaluated in the reproductive and vegetative phases.