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ABSTRACT Water stress is one of the limiting factors for obtaining maximum yield in soybean, which makes the identification of tolerant genotypes an important approach in breeding programs. The objectives of this work were evaluate soybean genotypes in conditions of water deficit, determine traits that allow the identification of genotypes tolerant to water deficit, and suggest promising crosses. Sixteen soybean genotypes were submitted to two osmotic potentials (0.0 MPa and -0.2 MPa) induced by PEG 6000 and the traits of germination and growing were evaluated. Genetic dissimilarity analysis was performed. There was genetic variability among genotypes for all traits, and significant interaction for root length, shoot and total fresh matter and dry root matter. Based on root length, it was possible to discriminate genotypes tolerant to water deficit. The cultivars BRS 7270 IPRO, TMG 2158 IPRO, UFUS Tikuna and UFU_P32 showed higher root length and stood out for dry root, fresh shoot and total fresh matter under water stress conditions and are indicated as promising parents in crosses.

Carrots (Daucus carota L.), a globally significant vegetable, lack extensive research on heterotic groups and diallel analysis to generate hybrid combinations. Thus, the objective of this study was to assess combining abilities and identify optimal carrot parents for producing hybrids suitable for tropical climates with elevated metabolite levels. Twenty carrot hybrids, ten parent plants, and three commercial cultivars were evaluated during the summers of 2020/2021 and 2021/2022. Agronomic evaluations were carried out and chlorophyll and carotenoid levels were determined, followed by a diallel analysis using Griffing’s Method III and GGE biplot analysis. There were significant general combining ability (GCA) effects for various agronomic traits, suggesting additive genetic effects. Based on GCA, cultivars 5, 4, and 2 were the most promising parents. Specific combining ability (SCA) revealed that hybrids 1 × 2 and 3 × 5 stood out in environment 1, whereas hybrids 1 × 5 and 5 × 3 performed well in environment 2. The GGE biplot analysis showed that hybrids 1 × 2 and 3 × 2 displayed larger average root diameters, belonged to the group with the best bolting percentages, and exhibited stability across environments. Moreover, hybrids 2 × 4, 3 × 1, 4 × 1, and 4 × 2 exhibited higher metabolite levels. These findings suggest the feasibility of obtaining superior hybrids tailored for the tropical carrot market.

ABSTRACT Genetic parameters and correlations are useful tools in breeding programs, helping to make decisions about the most efficient method of selecting soybean progenies. The objective was to determine genetic parameters and correlations between characters in 52 soybean genotypes, from 4 populations and to select the superior progenies for early cycle and grain productivity. The experiment was carried out in a randomized block design consisting of 52 RCF3:4 progenies and three controls (UFUS7010, TMG801, BRSGO7560). Agronomic and yield traits were evaluated. For the number of days to flowering and maturity, plant height at maturity and number of nodes at maturity, a high heritability estimate and favorable conditions for selection were observed. The existence of correlations between the characters was verified with the predominance of genetic causes, which allows the success in the indirect selection. By the Mulamba and Mock method, the highest selection gain was obtained, however, for the genotype-ideotype distance index method, greater gains were obtained for production components, therefore, 15 early cycle and productive superior RCF3:4 progenies were selected with a cycle between 79.0 and 105.0 days and production of 302.5 to 463.0 g plot-¹.

Seed collections are an alternative for conserving plant genetic resources. The characterization of plant species contained in the collections has been carried out with the help of tables of botanical, morphological, and agronomic descriptors, which are mainly used without parameters referring to their effective contribution to variability, causing an increase in time and labor in the characterization of plants. This study aimed to evaluate the relative importance of the morphoagronomic traits in 85 low-growing tomato accessions from the collection of the Federal University of Goiás and estimate the descriptors that most help in the dissimilarity of the accessions and thus remove the redundant descriptors. The experimental design consisted of three complete randomized blocks, 85 plots (each plot corresponding to a different accession), and 12 plants per plot. The evaluations used adapted morphological descriptors described in the MAPA guidelines for distinguishability, homogeneity, and stability trials. 56.4% of the selected morphoagronomic descriptors are essential in the characterization study since they significantly contribute to the discrimination of genetic divergence between low-growing tomato accessions. Discarding 43.6% of the descriptors does not cause loss of information, reduces costs, and streamlines the management of the classification of the collection.

ABSTRACT The selection indexes aggregate information to multiple characters and, with this, they are able to carry out the selection of a set of variables simultaneously. The objective was to verify the genetic potential of agronomic traits and to select soybean F3:4 progenies based on different selection strategies. 123 progenies and the parents were sown in randomized blocks with two replications. The gains of direct selection by the indexes, the sum of “ranks” and the genotype-ideotype were lower for all characters when compared to the gains of direct and indirect selection. The rank sum index stood out for achieving the highest total gain with 37.11%. The index of the genotype-ideotype obtained a lower gain (-0.48%) for the character number of days for flowering compared to the sum index of “ranks” (-0.54%) and reached a negative gain for the attribute insertion height of the first pod with -1.82%. The genetic potential of the F3:4 population is high and allows different selection strategies to be applied to reach superior genotypes. The progenies UFU 72, UFU 116, UFU 86, UFU 45, UFU 117, UFU 56, UFU 5, UFU 106, UFU 6, UFU 4, UFU 73, UFU 101, UFU 96, UFU 90, UFU 123, UFU 116, UFU 88, UFU 65, UFU 70, UFU 3, UFU 69 and UFU 37 were selected by both selection indexes. The UFU 72, UFU 90, UFU 88 and UFU 69 progenies are agronomically superior both in direct and indirect selection, as in Mulamba and Mock (1978) sum of “ranks” selections and genotype-ideotype.

ABSTRACT: White Mold (WM) is a yield–limiting disease found in soybean. However, up to now no cultivars have been genetically resistant to this disease. Given this context, the present study aimed to develop superior soybean lines with resistance to WM, while maintaining other desirable agronomic traits. Two early maturing soybean cultivars (i.e., EMGOPA 316 and MG/BR 46–Conquista), moderately resistant to WM were used for biparental crosses from which the analyzed population was derived. Therefore, we assessed the resistance to WM in early generation testing of this population. Additionally, we determined the agronomic traits, genetic parameters and selection gains. From 348 F2 genotypes, 35 transgressive genotypes moderately resistant to WM were identified, amongst which 22 genotypes showed desirable agronomic traits for early cycle and grain yield. Moreover, 69 lines were selected as the most promising genotypes for each agronomic trait (i.e. based on the number of days to flowering and maturity, plant height at flowering and maturity, number of nodes on main stem at flowering and maturity, number of pods, grain yield, etc.). Among these selected lines, ten progenies emerged as the superior genotypes for grain yield and early cycle. All together, these results demonstrated that the cross between EMGOPA 316 × MG/BR 46 (Conquista) revealed promising progenies with moderate resistance to WM and/or desirable agronomic traits. Thus, these lines could be used as future resources for breeding efforts aimed at improving resistance to WM.

Soybean is one of the most valuable commercial crops because of its high protein, carbohydrate, and oil content. The land area cultivated with soybean in subtropical regions, such as Brazil, is continuously expanding, in some instances at the expense of carbon storing natural habitats. Strategies to decrease yield/seed losses and increase production efficiency are urgently required to meet global demand for soybean in a sustainable manner. Here, we evaluated the effectiveness of an Ascophyllum nodosum extract (ANE), SealicitTM, in increasing yields of different soybean varieties, in two geographical regions (Canada and Brazil). In addition, we investigated the potential of SealicitTM to reduce pod shattering at the trials in Brazil. Three different concentrations of SealicitTM were applied to pod shatter-susceptible (SS) UFUS 6901 and shatter-resistant (SR) UFUS 7415 varieties to assess their impact on pod firmness. SS variety demonstrated a significant decrease in pod shattering, which coincided with deregulation of GmPDH1.1 and GmSHAT1–5 expression, genes that determine pod dehiscence, and higher seed weight per pod. SealicitTM application to the SR variety did not significantly alter its inherent pod shatter resistance, but provided higher increases in seed yield at harvest. This yield increase maybe associated with to other yield components stimulated by the biostimulant. This work demonstrates that SealicitTM, which has previously been shown to improve pod firmness in Arabidopsis and selected commercial oilseed rape varieties through IND gene down-regulation, also has the potential to improve pod resistance and seed productivity in soybean, a member of the legume family sharing a similar strategy for seed dispersal.

Soybeans are a grain-producing species of high international demand and occupy a prominent position in the Brazilian economy. The success of this crop in Brazil is due to public and private investments in production technologies and to breeding programs. It is through the seed that the genetic advances reach the producer. In this context, the success of a cultivar and high productivity depend on the quality of the seed. In view of the above, the objectives of the study were to evaluate the physiological quality of soybean cultivar seeds at different harvesting times. The experiment was conducted in an experimental area located at Fazenda Capim Branco, belonging to the Federal University of Uberlândia, in the 2016/2017 harvest. Ten soybean cultivars were evaluated (CD 2737 RR, UFUS 7415, UFUS 7910, UFUS Milionária, UFUS 7801, NA 5909 RG, UFUS 8301, TMG 7062 IPRO, UFUS Xavante and UFUS 6901) at four harvest times (R7, R8, R8+15, R8+30), constituting a 10 x 4 factorial. The experiment was carried out in a randomized complete block design with four replicates. For the evaluation of the physiological quality, germination, electrical conductivity and fresh matter and dry matter of seedlings tests were performed. In all tests the physiological quality of the seeds decreased with the harvest delay. Emphasis was placed on the cultivar NA 5909 RG, which showed the best means to delay the harvest in 15 and 30 days.

The soybean presents great economic expression and high impact in the Brazilian agribusiness. The productive potential of a cultivar is expressed according to the genetic constitution and the environment. The sowing time exerts influence on the agronomic traits of the soybean, impacting the yield of grains. The objective of this study was to evaluate the influence of the sowing season on the productive potential and the agronomic traits of soybean. The work was conducted at the Capim Branco experimental farm, belonging to the Federal University of Uberlândia. Twelve cultivars (UFUS 6901, UFUS 7415, BRSMG 68, TMG 801, TMG 7062 IPRO, TMG 2158 IPRO, BRS 7270 IPRO, NA 5909 RR, NS 6909 RR, CD 2737 RR, P98Y30 RR e BRASMAX Desafio RR) and four sowing seasons (October 22, November 5, December 22, 2016 and January 5, 2017) were used. The experimental design was a randomized block design with four replicates. The evaluated characters were: number of days for flowering and maturity, plant height at maturity, insertion height for the first pod, number of nodes at maturity, total number of pods, number of tainted pods and productivity. The sowing carried out in October and November contributed to obtain a larger number of nodes and a greater height of plants at maturity, which are agronomic traits favorable to higher productivity. Sowing delay seriously affected soybean yield and in the Uberlândia MG region the ideal sowing time was October 22, before the beginning of November. In the late sowing in December and January, the cultivars that had their productions less affected were the conventional cultivars BRSMG 68 and TMG 801.

Source of important vitamins, fibers, and minerals, the tomato (Solanum lycopersicum L.) stands out in the world agricultural scenario for its economic and social relevance and versatility. The Brazilian market is dominated by multinationals companies, and this market segment obtains cultivars from other countries, with genetics accurate to climatic conditions and cultivation method very different from those used in Brazil. As a result, the local cultivation of tomatoes plants becomes dependent on market variations and has required a material that has limited production efficiency. This study aimed to estimate genetic parameters from agronomic traits and to select industrial tomato lines using the selection index. A randomized block experimental design with three replications was used. Eighty­five industrial tomato lines from the germplasm bank of the Vivati Plant Breeding Ltda were evaluated. Each plot had 12 plants. The two central plants of each plot were evaluated. The evaluations were carried out using adapted morphological descriptors described in the guidelines for carrying out the distinguishability, homogeneity, and stability (DHE) tests of the Ministry of Agriculture, Livestock, and Supply of Brazil (MAPA). The genotypic determination coefficient (H2) of the traits related to fruit pericarp thickness, fruit firmness, fruit yield, average cycle, average number of fruits per plant, and soluble solids was high. The base index and the classic index presented the largest gain from selection for the fruit yield trait. Rank summation index and genotype­ideotype distance index had the highest total selection gain values. The tomato lines PXT­601 and PXT­610 stood out as superior genotypes by the methods of direct selection and by selection indexes.

The effect known as depression by inbreeding refers to the reduction on the average value of quantitative traits, related to plant reproduction and physiology, due to the homozygosis of deleterious alleles. This study evaluated the inbreeding depression and the genetic variability of agricultural traits and of the resistance to phytopathogens in inbred families of two exotic maize populations. The experiments were done in the experimental area of the Universidade Federal de Goiás, Regional Jataí, in the second harvest 2015. Fifty and 40 FS1 of NAP5 and NAP7 populations, respectively, were evaluated interplanting one row with a mixture of base population at every ten plots to estimate depression by inbreeding of the traits evaluated. The experimental design was randomized blocks, with three replications. The following traits were evaluated: AP – plant height (cm), AE – ear height (cm), FM – male flowering (days), PQ – number of broken plants, AC – number of lodged plants, PG – kernel production (kg plot-1). The greatest estimates of depression by inbreeding in the agricultural traits were observed for kernel production, with values of 51.2 and 38.9% for the populations NAP5 and NAP7, respectively. Among the traits of resistance to phytopathogens, the greatest estimate was observed for the stunting complex, with values of -58.9% in NAP5 and -74.2% in NAP7. Both populations under study presented genetic potential to be used in breeding programs with recurrent selection and, after some selection cycles, lineages with good agricultural standard and resistance to phytopathogens can be obtained.

Soy is one of the main cultivated species in the world with great economic expression and high impact on Brazilian agribusiness. The productive potential is expressed due to the genetic constitution of the cultivar and the environment in which it is exposed. The market demands for bean production require the ideal handling of the culture in order to optimize the yield potential of the plant. In this context, the handling of the culture is essential to achieve success when cultivating soy. Plant population influences the agronomic characters and consequently in the grain yield. Thus, this factor needs particular studies for each cultivar. The objective in this study was evaluating the influence of the plant population on the productive potential and agronomic characters in soy, in Uberlandia, Minas Gerais. The experiment was performed in Capim Branco Farm, which belongs to the Federal University of Uberlandia. The study was composed by 15 treatments in a 3x5 factorial scheme, constituted by three cultivars (UFUS 7415, UFUS 7401 and UFUS 6901) and five plant populations (200, 240, 280, 320 and 360 thousand plants ha-1). It was adopted the experimental outlining of randomized complete blocks, with five repetitions. The evaluated characters were: number of days to flowering and maturity (NDF and NDM), plant height at flowering and maturity (APF and APM), number of nodes at flowering and maturity (NNF and NNM), insertion height for the first pod (APV), total number of pods (NVT), thousand grain weight (P1000G) and productivity (PROD). It was noted that plant population didn’t interfere in the soy cycle, number of nodes and thousand grain weight. The cultivars UFUS 6901, UFUS 7415 and UFUS 7401 presented better yields in populations of 240, 280 and 320 thousand plants ha-1 respectively.

In recent decades, the expansion of soybean production in Brazil has been observed. This advance was motivated by the search of environments with better cultivation conditions, as well as the development of genotypes with wide adaptation. The diversity of "environments" hinders the process of selection and recommendation of cultivars, since the productive potential of a cultivar is given as a function of the sum of the genotype effect, the environment and the interaction between the latter two (G x E). In the case of this G x E interaction, regional studies are necessary in order to detail the differential behavior of the cultivars. Thus, the objective of this work was to evaluate the genotype interaction by environments, adaptability and phenotypic stability for grain yield, of fifteen soybean cultivars, in four sowing seasons, in order to identify cultivars that combine high productive potential, predictability of behavior and adaptation to the edaphoclimatic conditions of Uberlândia-MG. The trials were conducted at the Experimental Farm Capim Branco, in Uberlândia-MG. Fifteen soybean cultivars were evaluated in four sowing seasons (October 23, 2016, November 19, 2016, December 10, 2016 and January 14, 2017), in relation to grain yield. The experimental design was of randomized complete blocks, with three replications, in each season. Data were submitted to individual and joint analyzes. The G x E interaction was decomposed by the method proposed by Cruz and Castoldi (1991). The differential behavior of the genotypes was detailed by the adaptability and phenotypic stability by the methods of Eberhart and Russell (1966), Lin and Binns (1988) modified by Carneiro (1998), AMMI and Centroid. By the analysis of joint variance, it was observed the existence of the cultivar interaction by sowing times (C x E), for the grain yield trait, at the 5 % probability level by the F test. The C x E was predominantly complex in nature. The cultivar CD 2737 RR presented satisfactory results for the four sowing seasons in Uberlândia-MG, with high grain yield and predictability of behavior, by the evaluated methods. The cultivar NS 6909 IPRO was classified into favorable environments by the methods of Eberhart and Russell (1966) and Lin and Binns (1988) modified by Carneiro (1998). Considering Lin and Binns (1988) modified by Carneiro (1998) and Centroid the cultivar that is also classified for this cultivation condition is UFUS 8301. By AMMI, UFUS 7415, CD 2737 RR and UFUS Milionária are considered stable and adaptable.

Soybean has great economic importance in the world accordingly, this legume has been exploited in breeding programs aiming to provide cultivars with extensive grain yield, tolerant to pests and diseases, and adapted to different soil and climatic conditions. Therefore, the objectives of this work were to evaluate genetic parameters and correlations between soybean traits to select lineages to increase yield and improve agronomic traits. Experiments were carried out on the Capim Branco farm, of the Federal University of Uberlândia, harvest in 2016/2017. Fifteen morph-agronomic traits were assessed on twenty-two genotypes in a randomized complete block design with three replicates. Agronomic traits related to cycle, height, number of nodes and total pods have shown coefficients of genotypic determination higher than 70%. In addition, coefficients of variation of the number of days to the flowering and number of days to maturity were equal to 3.79% and 4.87%, respectively, indicating high homogeneity of data and low random variation. Among evaluated traits, ten have presented the ratios between the coefficient of genetic variation (CVg) and coefficient of environmental variation (CVe) above one, demonstrating high success likelihood in the selection of these traits. Fifteen genotypes have presented grain yield above the national average of the 2016/2017 harvest, which was 2882 kg h-1. Significant phenotypic correlations between traits ranged from -0.49 to 0.89, however genotype correlation was higher than the phenotypic ones, indicating that genetic factors have contributed more than the environmental factors. Traits related to cycle, height, and the number of nodes in the main stem have presented measures of H² and CVg / CVe with extensive magnitudes, evidencing the possibility of selection lineages having superior traits in the Soybean Breeding Program of the Federal University of Uberlândia. To increasing grain yield, the traits Number of pods of three grains and the Total number of pods were identified as appropriated to indirect selection based on the phenotypic and genotypic correlations. The 2lP14, B2P1, B2P28, B1P33 and 2AP11 lineages stand out as superior genotypes to direct selection.

The expansion of cotton crop into irrigated and high lands of Brazilian Cerrado, despite the possibility of increasing fiber yield, led to the occurrence of diseases previously considered secondary, such as white mold [Sclerotinia sclerotiorum (Lib.) de Bary]. Host genetic resistance is of extreme importance in integrated strategies to manage this disease. Resistance of Brazilian cotton genotypes, challenged with different strains of S. sclerotiorum, under two incubation conditions for disease progress was evaluated. In addition, possible correlation between oxalic acid and straw test methods to rank the genotypes was evaluated. Artificial inoculation was done when cotton plants reached the V2 phenological stage with fungi isolated from naturally infected soybean (ScS) or cotton (ScC) commercial crops. Control plants were inoculated with culture medium. After inoculation, plants were kept for one week either in a growth chamber or in greenhouse and evaluated for disease symptoms and severity. The oxalic acid test consisted of stem submersion of rootless cotton plants in a 2-cm layer of 20 or 40 mM solutions for 20, 44 or 68 h. A wilting scale was used to distinguish genotype's sensibility to the acid. The data were submitted to individual, joint, and multivariate analysis, grouping cotton genotypes by the Scott-Knott's test (p < 0.05), the hierarchical UPGMA and the non-hierarchical Tocher methods. Difference in aggressiveness between strains was identified, in which ScC led to greater disease severity. This result suggests a possible physiological specialization of S. sclerotiorum to different hosts. It was observed that the growth chamber environment provided more adequate conditions for S. sclerotiorum infection, thus allowing better selection of resistant cotton genotypes. UPGMA and Tocher grouping methods further confirmed that the evaluated genotypes differ from each other in resistance to white mold. No correlation between oxalic acid and straw test methods was observed.

This paper aims to present the features of the new soybean cultivar UFUS Milionária, which was developed by the Soybean Improvement Program of the Federal University of Uberlândia (UFU) through crossing between IAC-100 and Cristalina RCH cultivars, using the Single Seed Descent (SSD) method. UFUS Milionária is resistant to many diseases caused by the fungus, bacteria, and virus. In addition, it also has been proved well-adapted to many Brazilian states, showing high yield even under water deficit conditions and Asian-rust infection; average yield was 4,451 kg ha-1 in 2015/16 growing season.

The genetic breeding of soybean aims to obtain productive genotypes, so it is necessary that the genetic components, environment and the interaction between them be understood. The G x E interaction is the differential behavior of the genotypes against environmental. The objective was to study the G x E interaction and analyze the adaptability and stability of soybean genotypes under natural rust infection without fungicide. The experiment was conducted in the Genetic Breeding Program of the Federal University of Uberlândia. Fourteen soybean genotypes were evaluated, with 10 lines developed by the UFU Program (UFUS1117: 01, 02, 03, 05, 06, 07, 08, 09, 10 and 11) and 4 cultivars: UFUS 7415, UFUS Riqueza, TMG 801 and BRSGO 7560 in four seasons: 2013/14, 2014/15, 2015/16 and 2016/17, in a randomized complete block design. The G x E interaction was complex and the H2 was 85.97% indicating superiority of genetic variation in relation to the environment. The average grain yield was 2284.13kg ha-1. The genotype UFUS 1117-01 was identified by Eberhart and Russel, Wricke, AMMI 2 and Centroid as being a highly productive stability genotype. The UFUS 1117-07 showed high stability by Eberhart and Russel, Wricke, Lin and Binns modified by Carneiro methods and wide adaptability by Eberhart and Russel and Centroid. The genotype UFUS 1117-09 was identified as being adaptable to unfavorable environments by the Lin and Binns modified by Carneiro and Centroid methods, and UFUS 1117-10 presented favorable environmental adaptability by the Centroid method and high stability by Eberhart and Russel.

In analysis of the genetic diversity on soybean can be used agronomic, morphological and molecular traits, which are subjected to multivariate biometrical analysis. There are different multivariate methodologies available such as Euclidean distance, Mahalanobis distance and different hierarchical methods. However, studies that may assist in the choice of such methods are lacking. The aim of this paper was to evaluate the clustering standards of soybean genotypes using Euclidean and Mahalanobis distances, following different hierarchical methods. The experiment was conducted in "Capim Branco" farm which belongs to the Federal University of Uberlândia and were used a complete randomized block design composed of 15 soybean genotypes (nine breeding lines and six cultivars) and four replications. The agronomic traits evaluated were: number of days to flowering and to maturity, height of the plant at flowering and at maturity, height of the insertion of the first pod, number of nodes on the main stalk in flowering and at maturity, number of grains per pod, total number of pods, severity of Asian rust, number of pustules and yield. The data were submitted to multivariate analysis in GENES program. The Mahalanobis distance or the Euclidean distance obtained by agronomic traits allows the determination of soybean genetic diversity. The use of the Euclidean distance in hierarchical methods allows a greater group differentiation. The UPGMA method and the nearest neighbor method shows a greater accuracy using the Mahalanobis distance and Euclidean distance.

Knowledge of genetic diversity is of great importance to the contribution of plant breeding, as it helps plant breeders to better selecting parents for establishment of segregating populations. This knowledge is especially important to crops that presents a narrow genetic base as soybean. The objective of this work was to assess agronomic performance and genetic diversity of lines and soybean cultivars, in order to find those ones with potential to be used as parents in breeding programs. Experiment was carried out during 2015/2016 season in the Federal University of Uberlândia farm known as Capim Branco. A randomized complete block designed was applied in order to assess twenty-three morpho-agronomic features on twenty-four soybean genotypes. Significant genetic variability for all agronomic traits was found. Genotypes UFU B7, UFU B14, UFU B16, Msoy 6101 and UFUS 7910 were set as early maturity soybean, with life cycle duration ranging from 107.3 to 111 days. Genotypes UFU B1, UFU B3, UFU B8 and UFU B16 presented productivity values higher than national average of 2.870 kg ha-1. Genotypes were clustered by UPGMA, Tocher and canonical variables methods. Both UPGMA and Tocher methods formed four groups. NDF was the major contributor to genetic diversity. Hybridizations between UFU B3, UFU B8, UFU B16 genotypes with UFU B1 genotype might be promising for establishment of segregating populations shown superior genetic variability. Under these circumstances, it was concluded that agronomic features assessed were useful on detection of parents with potential to UFU's soybean breeding program.

This work aimed to study agronomic traits of soybean genotypes by path analysis and correlation estimates. We have used a randomized complete block design to assess 35 soybean genotypes with three replications, which 31 lines were from the breeding program of the Federal University of Uberlândia, Brazil, plus four commercial cultivars. We have assessed features number of days to the blooming, plant height at blooming, number of days to maturity, plant height at maturity, first pod height, number of nodes on the main stem at maturity, number of pods with one, two and three seeds per plant, total number of pods per plant, number of seeds per pod and grain yield. The features plant height at maturity and number of nodes at maturity have presented significant correlations phenotypic and genotypic positive. 100-seed weight was positively correlated with grain yield shown high direct phenotypic and genotypic effects being, therefore, useful for indirect selection aiming the grain yield increase.

The use of different evaluation methods of adaptability and stability in a breeding program is essential to obtain more accurate results of the lines that have been studied. The purpose of this research is to study the adaptability and stability of 25 soybean lines derived from the soybean breeding program, and for that, it was used parametric and non-parametric analysis at the Federal University of Uberlandia. The experiment was set up in randomized complete block design with three replications in three sowing periods (November 2006, November 2007 and November 2008) and conducted in Campo Alegre de Goias, Brazil. Thirty soybean genotypes were evaluated, including 25 late-cycle lines and five cultivars (BRS/MG Garantia, UFUS Impacta, UFUS Xavante UFUS Milionária and M-Soy 8914) as controls). Grain productivity was determined for each block. The average yield was 3104.201 kg ha-1. Adaptability and stability were determined using Eberhart and Russel (1966), Lin and Binns (1988) modified by Carneiro (1998) and Centroide (ROCHA, 2005) methods. The UFUS 6 and UFUS 21 lines and the UFUS Impacta and UFUS Xavante cultivars stood out because they had the highest average grain yield, highest adaptability and stability regardless of evaluation method.

Breeding programs strive to obtain cultivars with superior traits. The association between these characters, such as those estimated by correlation coeficients, are important to the breeding selection process. In this study we analyzed phenotypic and genotypic correlations between yield and other agronomic traits in soybean progenies derived from various crosses to support breeding line selection in the the soybean breading program of the Federal University of Uberlandia (UFU). The experiment was carried out in the 2011/2012 growing season at the Capim Branco research station in Uberlandia, Minas Gerais, Brazil. Seventy-one soybean lines were evaluated using a randomized complete block design with three replications. In these plots plants were evaluated for the number of pods, grain yield per plant, number of days for flowering, plant height at flowering, number of days for maturity, plant height at maturity, height of the first pod insertion, number of grains per pod and grain yield per plant. The estimates for genotypic correlations were equal or greater than those for the phenotypic correlations for all the evaluated traits. This suggests a small effect of environmental factors on the trait expression. An exception of this behavior was the correlation between plant height at flowering and plant height at maturity. In this case, although the signs for the genotypic and phenotypic correlations were the same, the value for the last was greater than that for the former.. The late flowering and late-maturing plants were taller. Also, selecting plants for higher number of pods ultimately contributed for the selection of plants with higher grain yield. The selection of late-flowering and late-maturing plants have yielded taller plantsin the same way that the selection for a higher pod number could promote the selection and improvement of grains yield trait.

The purpose of this study was to analyze the genetic diversity among soybean genotypes inoculated with Heteroderaglycines race 3. The experiments were conducted in a greenhouse. In two performance tests of morphological characteristics andresistance to the pathogen, 27 soybean genotypes were assessed. The coefficient of genotypic determination was estimated by themethod of analysis of variance and the genetic diversity analyzed based on dendrograms and optimization method. The estimatedcoefficients of determination indicated a predominantly genetic origin of the genotypic differences in the traits. The genetic variabilitywas maintained in the superior genotypes, which can be used in breeding programs for resistance to soybean cyst nematode

A diferenciação de cultivares é realizada por margem mínima de descritores específicos de cada espécie. Atualmente, são usados cerca de 38 descritores entre os obrigatórios e os adicionais para diferenciar cultivares de soja. Entretanto, estes ainda são insuficientes, o que torna evidente a necessidade de ampliar a lista de descritores utilizados, os quais devem ser previamente identificados e avaliados. O presente trabalho teve como objetivos identificar e avaliar novas características para fins de diferenciação de cultivares de soja. A pesquisa foi realizada em casa de vegetação do Departamento de Fitotecnia (DFT), da Universidade Federal de Viçosa (UFV), e foram realizados quatro experimentos em quatro épocas diferentes (dois no verão e dois no inverno). Os tratamentos foram constituídos de 11 cultivares de soja. O delineamento experimental foi inteiramente aleatorizado com cinco repetições, em que cada unidade experimental foi constituída por um vaso com duas plantas. Foram avaliadas as características comprimento do hipocótilo (CH), comprimento do epicótilo (CE), comprimento do pecíolo da folha unifoliolada (CPFU), coeficiente da forma da base da folha unifoliolada (CFB), coeficiente da largura da base da folha unifoliolada (CLB), comprimento do pecíolo da primeira folha trifoliolada (CPFT) e comprimento da raque do folíolo terminal da primeira folha trifoliolada (CRFT). Para o estudo, foi realizada a análise discriminante de Anderson (1958) e as análises estatísticas foram realizadas utilizando o aplicativo computacional em Genética e Estatística, denominado Programa Genes. Para todas as características analisadas, foram observadas diferenças significativas nas quatro épocas de semeaduras. Pela análise discriminante, foi possível distinguir cultivares de soja. Conclui-se que as características são úteis como descritoras adicionais de cultivares de soja.Cultivar differentiation is carried out by the least margin of specific descriptors in each species. Nowadays, approximately 38 descriptors, including the obligatory and additional ones, are used to differentiate soybean cultivars. Since these descriptors are still not enough, it is necessary to increase the number of descriptors used, which should be previously identified and evaluated. The objectives of this study were to identify and evaluate new traits for the differentiation of soybean cultivars. The experiments were conducted in a greenhouse at the Plant Science Department of the Federal University of Viçosa at four different times (two during summer and two during winter). The treatments consisted of 11 soybean cultivars arranged in a complete randomized design with five replicates. Each experimental unit consisted of one pot with two plants. The following characteristics were evaluated: hypocotyl length (CH), epicotyl length (CE), petiole length of the unifoliate leaf (CPFU), base shape coefficient of the unifoliate leaf (CFB), base width coefficient of the unifoliate leaf (CLB), petiole length of the first trifoliate leaf (CPFT) and rachis length of terminal leaflet in the first trifoliate leaf (CRFT). Anderson's discriminant analysis was performed, and statistical analyses were carried out using the Genetics and Statistics software 'Programa Genes'. Significant differences were found for all characteristics in the four sowing times. Discriminant analysis allowed the differentiation of the soybean cultivars. It was concluded that the characteristics are useful as additional descriptors of soybean cultivars.

O objetivo desta pesquisa foi identificar genótipos de soja com adaptabilidade e estabilidade de comportamento para resistência ao oídio em condições de campo. O trabalho foi realizado no Campo Experimental Professor Diogo Alves de Mello, do Departamento de Fitotecnia, da Universidade Federal de Viçosa (UFV), em Viçosa, Minas Gerais. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições, disposto em parcelas subdivididas, com 15 genótipos (parcelas) e sete épocas de avaliação (subparcela). A avaliação da incidência e severidade do oídio nos genótipos foi realizada por meio da quantificação visual do nível de infecção (NI) provocado pelo oídio, sendo avaliados o nível de infecção da área foliar infectada pelo oídio (NIAFI) e o nível de infecção do folíolo mais infectado pelo oídio (NIFI). Foram realizadas a análise de variância e análise de adaptabilidade e estabilidade conforme EBERHART & RUSSELL (1966). Os resultados permitiram tirar as seguintes conclusões: os genótipos que apresentaram os melhores níveis de resistência, em geral, também foram os de melhor adaptabilidade e estabilidade, tanto para NIAFI quanto para NIFI, com destaque para: UFV 89-361826 T2, UFV 94-334268, UFV-16 e UFV-19, FT-10 RC5 (F3), FT-Abyara RC6 (F2), Doko RC, FT-Abyara RC5 (F4), enquanto que os mais suscetíveis foram os de pior previsibilidade (estabilidade) de comportamento, com destaque para UFV 94-5126, FT-104, UFV 94-3500, FT-Cristalina, FT-Estrela e BR-16.The objective of this research was to identify soybean genotypes with good adaptability and stability of behavior for resistance to powdery mildew in field conditions. The work was carried out at the Professor Diogo Alves de Mello Experimental Station, Agronomy Department of the Federal University of Viçosa (UFV), Viçosa, Minas Gerais. The experiment was arranged in a randomized block design, in split-plots, with 15 genotypes (plots) and seven evaluation times (subplots), with four repetitions. Evaluation of incidence and severity of powdery mildew in the genotypes were accomplished by visual quantification of fungus infection level (IL), assessing the level of infection of the leaf area infected (NIAFI) by the powdery mildew and the level of infection of the most infected leaflet (NIFI). Data were examined by analysis of variance and analysis of adaptability and stability according to EBERHART & RUSSELL (1966). The results allowed to get to the following conclusions: the genotypes that showed the highest resistance levels, were, in general, also the ones of higher adaptability and stability, both for NIAFI and NIFI, standing out UFV 89-361826 T2, UFV 94-334268, UFV-16 and UFV-19, FT-10 RC5 (F3), FT-Abyara RC6 (F2), Doko RC, FT-Abyara RC5 (F4), whereas the most susceptible genotypes were the ones of worse predictability, standing out UFV 94-5126, FT-104, UFV 94-3500, FT-Cristalina, FT-Estrela and BR-16.

This work aims to study the genetic variability of 22 biparental crosses of soybean through multivariate techniques. The experiment was carried out in a randomized complete block design with three replications, consisting of 110 genotypes from 22 biparental crosses and cultivars UFUS Riqueza, UFUS Impacta, UFUS Xavante UFUS Millionária and MSoy 8211 which were used as control. The characters evaluated were number of days until flowering and until maturity, plant height at flowering and at maturity, number of pods with one, two or three seeds, total number of pods, weight of plant and first pod yield. The population evaluated showed genetic variability for most traits. Plant height at maturity, pods with one seed and grain yield were the traits that contributed the most to genetic diversity among the soybean crosses studied. The three clustering methods used in this study were effective in representing the genetic distance in soybean. Hybridizations between lines derived from crosses CR13 and CR14 with cultivar UFUS Impact or hybridizations between lines derived from crosses CR5 and CR10 with lines derived from crosses CR21 and CR12 show promise for obtaining segregating soybean populations.

Estudos de adaptabilidade e estabilidade são de grande importância para os programas de melhoramento de plantas, tornando possível a identificação de cultivares com comportamento previsível frente às variações ambientais. O objetivo deste trabalho foi avaliar, com base na produtividade de grãos, a adaptabilidade e a estabilidade de genótipos de soja de ciclo tardio, cultivados em três anos consecutivos em Porto Alegre do Norte-MT. Os experimentos foram conduzidos na Fazenda Piraguassu, pertencente ao Grupo Itaquere, no município de Porto Alegre do Norte-MT. O delineamento experimental foi o de blocos completos casualizados com três repetições, envolvendo 25 linhagens e quatro cultivares de soja (BRS Garantia, UFUS Impacta, UFUS Xavante e MSOY 8914). Os métodos de Eberhart e Russel (1966) e Lin Binns modificado por Carneiro (1998) permitiram identificar as linhagens UFU-1 e UFU-14 adaptadas a ambiente favorável, alta estabilidade e elevadas médias de produtividade de grãos. Todas as metodologias propostas foram concordantes em destacar a UFU- 16, devido ao maior desempenho produtivo, à adaptação a ambiente favorável, entretanto com baixa estabilidade.

Na cultura da soja, o déficit hídrico é um dos fatores limitantes à obtenção da máxima produtividade. A identificação de genótipos com capacidade de tolerância à seca é fundamental para a solução desse problema. Objetivou-se, neste trabalho, analisar a qualidade fisiológica e as respostas bioquímicas de cultivares de soja (MG/BR 46 Conquista, UFUS Carajás, UFUS Impacta, UFUS Riqueza e UFUS Xavante) submetidas ao estresse hídrico com soluções de PEG 6000 em diferentes níveis de potencial osmótico (0; -0,1; -0,2; -0,3 e -0,4 MPa). Avaliou-se a qualidade fisiológica das cultivares por meio dos testes de comprimento de plântulas e biomassa fresca e seca de plântulas. As respostas bioquímicas foram avaliadas pela detecção do ácido indol-acético, pelo conteúdo de sacarose e pelo transporte de água nas plântulas. A cultivar UFUS Riqueza apresentou os melhores desempenhos nos testes de qualidade fisiológica, conteúdo de sacarose, absorção e velocidade de absorção de água em plântulas. A cultivar UFUS Xavante mostrou a maior concentração de AIA e o maior massa de plântulas no teste de transporte de água.

O conhecimento das relações existentes entre caracteres, tais como estimados pelas correlações, tem sido de grande relevância no melhoramento vegetal, pois fornece informações úteis ao melhorista no processo de seleção. Todavia, a quantificação e a interpretação da magnitude das correlações não implicam efeitos diretos e indiretos. Nesse contexto, a análise de trilha apresenta-se como uma alternativa viável. Os objetivos deste estudo foram avaliar as correlações fenotípicas e genotípicas entre caracteres agronômicos importantes no melhoramento genético da soja, realizar análise de trilha, tendo como caráter principal a produtividade de grãos e identificar critérios de seleção indireta para produtividade de grãos. Foram conduzidos dois experimentos em condições de casa de vegetação, semeados em fevereiro e em dezembro de 2007. Os tratamentos foram constituídos de 90 genótipos de soja incluindo linhagens e cultivares. Adotou-se o delineamento de blocos casualizados com três repetições. Cada unidade experimental foi constituída por três plantas cultivadas em substrato num vaso de 3dm3. Avaliaram-se os caracteres: número de dias para o florescimento e maturidade; altura da planta no florescimento e maturidade; número de nós na haste principal; altura da primeira vagem; número de vagens; produtividade de grãos; número médio de grãos por vagem; e o peso de 100 grãos. As correlações genotípicas tiveram, predominantemente, magnitude superior às correlações fenotípicas, sendo ambas de mesmo sinal nas duas épocas de semeadura. A partir das correlações fenotípicas, genotípicas e a análise de trilha identificaram-se o caráter número de vagens por planta, independentemente da época de semeadura, de maior efeito favorável sobre a produtividade de grãos.

The aim of this study was to evaluate the adaptability and stability of soybean genotypes grown in two soybean producing micro-regions (301 and 401), in the harvest seasons of 2006/2007 and 2007/2008. 16 soybean genotypes were studied (six soybean lines of the breeding program of Monsoy Ltda. and 10 cultivars). The experiments were conducted in a randomized complete block design, with three replications. Individual and group analyses were performed and the parameters of adaptability and stability were estimated by the methods proposed by Eberhart and Russel, Annicchiarico, Linn and Binn and Centroide. The results showed interaction of genotypes and environments showing different behavior of the genotypes according to environmental fluctuations. The methods of Annicchiarico, Linn and Binns modified by Carneiro and Centroid, were consistent with each other and allowed to identify among the genotypes, the highest stability and adaptability. The cultivars M-SOY 7908 RR, M-SOY 8199 RR and BRS Valiosa RR have general adaptability and stability. The Strains LG4 and LG5, and cultivar M-SOY 7908 RR showed high adaptability and stability in favorable environments and the control M-SOY 8199 RR for unfavorable environments and the strain CC4 showed high stability and adaptability in favorable environments. The cultivars MSoy 8199 RR and BRS Valiosa RR had adaptation to unfavorable and general environments, considering the four methods that were evaluated in this study.

Este trabalho teve como objetivo avaliar o comportamento médio, a interação genótipos x ambientes (GxA), a adaptabilidade e estabilidade de sete cultivares de soja em três épocas de semeadura em Uberlândia-MG. Os ensaios foram conduzidos na Fazenda Capim Branco, pertencente à Universidade Federal de Uberlândia. As semeaduras foram realizadas nos dias 29 de outubro (1ª época), 24 de novembro (2ª época) e 17 de dezembro (3ª época) de 2007. O delineamento experimental adotado foi o de blocos casualizados, sendo sete genótipos (UFUS Xavante, UFUS Riqueza, UFUS Guarani, UFUS Milionária, Msoy 8001, Msoy 8411 e Msoy 8914) com três repetições em cada uma das três épocas de semeadura. As médias foram comparadas pelo teste de Tukey a 5% de probabilidade. A análise de adaptabilidade e estabilidade fenotípica dos genótipos foi feita pelos métodos de Eberhart e Russell (1966), Lin e Binns (1988) modificado por Carneiro (1998) e centróide (NASCIMENTO et al., 2009). Para o caráter produtividade de grãos, a cultivar UFUS Xavante foi classificada como de adaptabilidade específica para ambiente favorável e de alta estabilidade. As demais cultivares foram classificadas como sendo de adaptabilidade geral. Para o teor de óleo, as cultivares Msoy 8914 e UFUS Xavante comportaram se como de alta estabilidade e foram classificadas como de adaptabilidade geral alta. Para o caráter teor de proteína, todas as cultivares se comportaram como de ampla adaptabilidade e baixa estabilidade.

ABSTRACT In Brazil, as the soybean crop expands the losses caused by nematodes as well as its incidence in producing areas have increased. Therefore, this work aimed to develop a non-genetically modified soybean which combines desirable traits as the root-knot nematode resistance, early-maturity, high seed yielding, and high oil and protein contents. Consequently, seeds (F2) derived from the double-crossing between (Guarani x Sambaiba) x (M Soy 6101 x Conquista) were bulked to grow the F3 generation. Following generations were advanced by the SSD method of breeding until F6. Thus, plants showing superior characteristics were planted separately to perform progeny tests and then advanced breeding lines were thoroughly tested and compared to standards in representative environments across several locations in the Midwestern region in Brazil. As a result, we developed an early-soybean with cycle-length of 107 days; usually cycles range from 90 to 160 days. It presents desirable traits as high yield (3677 kg ha-1), Brazilian national average ranged between 2.5 and 3 thousand kg ha-1; broad adaptability, with 19% of oil, and 38.4% of protein on the seeds. Oil and protein standard contents are 20% and 40%, respectively. In addition, it is root-knot nematode (Pratylenchus brachyurus) resistance, not differing statistically (RF = 1.70) from the expected value given by Crotalaria spectabilis (RF = 1.14). Accordingly, we recommend this new cultivar to producers that intend to grow a second crop of either corn or cotton in the summer, or for crop producing areas with high incidence of P. brachyurus.

ABSTRACT Evaluation of the genetic potential of parent plants is fundamental for obtaining superior populations with desirable agronomic characters. The aim of this work was to obtain estimates of the general and specific combining abilities of five soybean parents to identify the most promising parents and hybrid combinations for the development of superior genotypes for grain yield. In this study, two groups of soybean cultivars were selected: group I resistance (UFUS 7910 and BR/MG 46 Conquista) and group II (TMG 4182, TMG 4185 and BRSGO Chapadões). The parents were crossedin a 2 x 3 partial diallel scheme, and the experiment was analyzed according to Griffing’s (1956) parent and F1 model and adapted by Geraldi and Miranda Filho (1988). Six hybrid combinations and respective parents were arranged in randomized complete blocks with four repetitions. The following characters were evaluated: number of days for flowering and maturity, height of the plant in flowering and at maturity, number of nodes in flowering and at maturity, number of total pods and grain yield per plant. The BR/MG 46 Conquista, UFUS 7910 and BRSGO Chapadões parents contributed to obtaining productive segregant populations due to additivity for the total number of pods and grain yield per plant. The hybrid combinations BRSGO Chapadões x BR/MG 46 Conquista, BRSGO Chapadões x UFUS 7910 and TMG4182 x BR/MG 46 Conquista are promising for obtaining populations with high productive potential.