RESUMO Este trabalho consiste no levantamento florístico e estudo taxonômico da família Asteraceae, da Estação de Pesquisa, Treinamento e Educação Ambiental, Viçosa, Minas Gerais. Foram amostradas 61 espécies circunscritas a 39 gêneros e 10 tribos. As tribos mais ricas em número de espécies foram Eupatorieae, com 22 espécies, Heliantheae com 11 spp., Astereae, com 10 spp. e Vernonieae com 8 spp. Os gêneros com maior abundância em número de espécies foram Mikania Willd. com oito spp., Baccharis L., com sete spp., Vernonia Schreb. com seis spp e Chromaloena DC. com três spp. Os demais gêneros apresentaram uma ou duas espécies. São fornecidas nesse trabalho chaves analíticas, descrições, ilustrações, comentários taxonômicos e distribuição geográfica para cada espécie.

Plant breeding, associated with other areas, as well as the registration and protection of cultivars, have brought relevant contributions to turn soybean into one of the most important crops for the Brazilian agribusiness. Potential additional soybean descriptors for cultivar protection purposes such as the length of the hypocotyl and epicotyl have been reported in the literature. Thus, the objective of this work was to study the effect of soil volume, plant density per pot and crop and cultivar depth on the length of the hypocotyl and epicotyl and the height of soybean seedlings. The study conducted 4 experiments, in which the length of the hypocotyl and epicotyl and the height of soybean seedlings were evaluated at the V2 and V3 stages. Experimental units were submitted to pots with three volumes of soil (1, 2 or 3 dm3), three quantities of plants per pot (1, 2 or 3), three sowing depths (1, 2 or 3 cm) and four cultivars [TMG 4185, BRSMG 68 (Vencedora), BRS 7980, BRS 8381]. Results showed that soil volume, plant density and sowing depth had no effect on hypocotyl length evaluated at the V2 stage and that sowing depth had no effect on epicotyl length. However, soil volume, plant density, sowing depth and cultivar variations had an influence on plant height, and the soybean cultivars showed distinguishability for hypocotyl and epicotyl length at the V2 and V3 stages, being considered potential soybean descriptors.

The length of the hypocotyl has been highlighted as a potential descriptor of the soybean crop. However, there is no information available in the published literature about its behavior over several planting times. The present study aimed to identify soybean cultivars with stability and predictability of hypocotyl length behavior through neural networks and traditional adaptability and stability methodologies. We analyzed 16 soybean cultivars in 6 planting seasons under greenhouse conditions. In each season, a randomized block design with 4 replications was adopted. The experimental unit was composed of 3 plants. The plot mean was used in the analysis. Hypocotyl length data were analyzed by analysis of variance and Tukey’s test. Then analyses were carried out using the Traditional Method, Plaisted and Peterson, Wricke, Eberhart and Russell, and Artificial Neural Networks. A significant effect (p<0.01 by the F test) was identified for Cultivars versus Planting Season and Planting Seasons and Cultivars. Cultivars BRS810C, BRSMG760SRR, TMG1175RR, and BMX Tornado RR showed lower averages, high stability, and general adaptability regarding soybean hypocotyl length whereas the cultivar BG4272 presented higher mean, high stability, and general adaptability. Identification of soybean cultivars of predictable and stable behavior as to hypocotyl length contributes to Soybean Improvement as it further our knowledge on the potential descriptor and the possibility of increasing the number of descriptors.

ABSTRACT:Hybridization is an important improvement method used in the soybean culture. However, there is little information on the recommended relative moisture and air temperature degree for artificial pollination. Therefore, this study aimed to determine the efficiency of artificial hybridization between soybean parents according to different periods of the day. Artificial pollination of 14 hybrid combinations occurred in greenhouse in three periods of the day. The parents were: TMG 801, TMG 803, BRSGO 7560, BRS Valiosa RR, Agua-Marinha RR and NK 7059 RR. The studied variables were: relative moisture, air temperature, number of days to flowering, performed artificial pollination, pods without sepal, produced seeds, germinated seeds, hybrid plants and percentage of pods without sepals. Data were submitted to normality and homogeneity of variance test, analysis of variance, Tukey, Scheffé and χ2 tests, and correlation analysis. Six hundred and seventy-two artificial pollinations were performed. From which were obtained 436 pods without sepals and approximately 90% of produced seeds was hybrid. The results indicated that artificial pollinations performed in January, with parent used in this study, were more efficient in the period from 10:00 a.m. to 12:00 a.m., with mean relative moisture of 34.1% and mean temperature of 38.5 ºC and 2:00 a.m. to 4:00 p.m. with 30.7% and 41.6 ºC respectively for relative moisture and means of temperature.

Objetivou-se identificar diferença entre grupos de cultivares, estudar o efeito da profundidade de semeadura sobre o diâmetro do hipocótilo e o comportamento do diâmetro do hipocótilo ao longo do desenvolvimento das plantas de soja. Para isto analisou-se cultivares de soja em estádio inicial de desenvolvimento, em condições de casa de vegetação, quanto ao diâmetro do hipocótilo em dois sentidos: COTsentido dos cotilédones e OPCOTsentido oposto aos cotilédones. Os dados foram analisados por meio da análise de variância, teste de médias (Tukey ou Scott-Knott), regressão e correlação fenotípica e genotípica. E, estimados o coeficiente de variação e coeficiente de determinação genotípica. Verificou-se que as cultivares de soja se diferenciam quanto ao diâmetro do hipocótilo e identificou-se grande influência genética em detrimentos aos efeitos ambientais. Semeadura de 1 à 3 cm de profundidade não influenciou o diâmetro do hipocótilo, avaliados nos estádios V2 e V3, ao analisar plantas das cultivares TMG 4185, BRSMG 68 [Vencedora], BRS 7980 e BRS 8381. As cultivares 98Y30, TMG1174RR e TMG 4185 apresentaram comportamento semelhantes quanto ao diâmetro do hipocótilo no período de 0 à 48 dias após o estádio de desenvolvimento V1.