ABSTRACT Developing fast-cooking, mineral-biofortified common bean lines represents an important innovation for breeding programs. Thus, this study was conducted to determine whether elite Mesoamerican common bean lines differ for cooking time and mineral concentration and to select fast-cooking, mineral- biofortified lines. The experiments were carried out in two growing seasons, in which 16 common bean genotypes were evaluated. Cooking time was determined using a Mattson cooker, and the minerals were analyzed by acid digestion. The resulting data were subjected to individual analysis of variance, combined analysis of variance, clustering by the Scott-Knott test, and selection index (multiplicative). There was a significant genotype × environment interaction effect for cooking time and the concentrations of potassium, iron, zinc and copper. Only the phosphorus concentration showed no genetic variability between the common bean lines. The ranking of the best common bean lines differed for all traits examined in the different environments, according to the Scott-Knott test. The use of the multiplicative selection index allows selecting superior common bean lines for all traits, namely, DF 07-11, DF 08-21, DF 08-20 and DF 08-28. These lines exhibit a very short cooking time (up to 15 min), high potassium concentration (> 12.00 g kg-1 of dry matter) and the highest mean values of micromineral concentration, and will thus be selected by the breeding program.

ABSTRACT Powdery mildew is an important disease in tomato, which requires technologies for its control. Homeopathy is a science that has been improved as an alternative method in agriculture. Thus, this study aimed to evaluate the homeopathic medicine Ferrum sulphuricum in 6, 12, 24, 48, 72 and 96CH dynamizations on powdery mildew control. The experiment was conducted from May to June 2013 in a greenhouse, in split-split- plot design, and the results were compared with the controls 30% ethanol and distilled water. We evaluated the area under disease progress curve (AUDPC), relative chlorophyll index (SPAD), influence on plant growth by volume and mass of roots, and mass of fruits and shoots and even the pathogen sporulation on leaves. For the AUDPC, all the dynamizations reduced the disease. The Santa Clara genotype showed up to 41% less and Cedro 31% less disease compared with the control ethanol, in the upper third of the plant. For the SPAD index, there was an increase of up to 322% in the middle third of the plant treated with 24CH dynamization. For the growth variables, all the dynamizations increased up to 197% the volume and weight of roots for Cedro and Santa Clara. The 6, 12, 24, 72 and 96CH dynamizations reduced the pathogen sporulation on Santa Clara tomato leaves by up to 40%. The data indicate that the medicine Ferrum sulphuricum can control powdery mildew on tomato, increase the growth of plants and that there is a differential response according to the host genotype.

ABSTRACT Cordia oncocalyx Allemão Baill., widely known as “pau-branco”, is a native species from the Caatinga (Brazilian Savannah) and has socioeconomic and environmental potential; however, there are few silvicultural studies on this species. Therefore, this paper aimed to analyze and compare the biometric characteristics of diaspores and seeds through manual biometrics and by digital image processing, and to evaluate the in vitro and ex vitro germination of C. oncocalyx. In the biometrics evaluation, three hundred diaspores and three hundred seeds were used, applying manual and digital biometrics. Subsequently, ex vitro emergence was determined, testing mechanical scarification (in different regions of the diaspore) and chemical scarification (immersion in sulfuric acid for 90 min and 180 min). Finally, in vitro germination was tested with different compositions of Murashige & Skoog (M&S) culture medium and sucrose addition. Results showed that digital image processing is a viable and fast technique to obtain the biometric parameters of C. oncocalyx fruit and seeds. Chemical and mechanical treatments on diaspores have not influenced seed emergence (0.33%). The composition of the culture medium has influenced the germination percentage, and the maximum value of 96% % was obtained with 6 g/L of sucrose and 0.90 g/L of M&S medium. Thus, the seminiferous propagation of C. oncocalyx can be performed successfully when the seeds are germinated in vitro, and the digital image processing shows the solidity and applicability aiming to evaluate the quantitative parameters of seed and fruit of this species.

ABSTRACT The rich genetic diversity and wide adaptation of rice (Oryza sativa L.) to different environments provide fundamental resources for its conservation and improvement. The analysis of canonical correlations can be used to increase the efficiency of selecting superior genotypes, as several traits are evaluated simultaneously. Thus, this study aimed to compare morphoagronomic traits and estimate the magnitude of the association and interdependence between two groups of traits in genotypes of special types of rice. The experiment was carried out between November 2020 and April 2021 at the Department of Plant Science of the Federal Rural University of Rio de Janeiro (UFRRJ), Seropédica - RJ. The experimental design consisted of randomized blocks, with four replications. Seventeen genotypes were evaluated, five of them consisting of white rice and eleven special types of rice. Two groups of variables were used to determine the canonical correlations, with group I composed of four morphological traits and group II composed of four yield components. Significant differences (P<0.01) were observed between genotypes for the eight evaluated traits. The first, second, and third pairs showed significant canonical correlations at a 5% probability, demonstrating that these groups are not independent. The selection of superior genotypes for production can be based on choosing plants with higher flag leaf thickness, higher height, and lower flag leaf angle.

ABSTRACT The objective of this work was to verify the contribution of seed inoculation with the bacterium Azospirillum brasilense to promote growth on yield components in wheat crop. For this, experiments were carried out in different locations (Santa Maria and Cruz Alta, RS, Brazil), sowing times (June and July) and years of cultivation (2013 and 2014). A randomized block design with three replications was used. The treatments were composed by the combination of ten cultivars, three nitrogen managements and two types of inoculation (10 x 3 x 2). Inoculation was carried out with liquid inoculant in the seeds. The components of grain yield were evaluated. The average number of tillers per plant was influenced by seed inoculation (1.63 and 1.72) when uninoculated and inoculated, respectively. On the other hand, the hectoliter mass responded inversely, reducing to 75.7 kg hL-1. Inoculation with A. brasilense increased the grain mass (1%) and had no positive influence on the variables number of ears and spikelets per ear, grain yield and hectoliter weight.

ABSTRACT The use of resistant cultivars is one of the strategies for downy mildew management. The objective of this study was to evaluate the vertical and horizontal resistance of F5:6 progenies of carotenoidbiofortified lettuce to virulence phenotypes of Bremia lactucae 63/63/51/00, 63/31/19/00 and 63/63/19/00. The experimental design was completely randomized and subdivided into plots that were evaluated over time. In the plots, 12 genotypes of lettuce were used, and the subplots were monitored over time (7th to the 18th day after inoculation). For each virulence phenotypes of Bremia lactucae, a separate experiment was performed with three replicates. To select resistant genotypes, plants were inoculated with distilled water, sporangia removed from infected tissues and Tween 20. The genotypes were evaluated when sporulation appeared on cotyledonary leaves of the susceptible cultivar Solaris, verifying the proportion of necrotic and sporulated plants. There was a correlation between genotypes and times for all virulence phenotypes evaluated. Genotypes UFU-189#2, UFU-206#1, UFU-215#3 and UFU-215#14 showed vertical resistance to virulence phenotypes 63/63/51/00, 63/31/19/00, and 63/63/19/00 of B. lactucae. Horizontal resistance levels were observed in genotype UFU 206#1 for virulence phenotypes 63/63/51/00 and 63/31/19/00; in genotype UFU-66#7 for virulent phenotype 63/31/19/00; and in genotype UFU-215#10 for virulence phenotype 63/63/19/00.

ABSTRACT Lima bean is an important crop in Northeastern Brazil and a source of food and income for farmers in the region. However, there have been few genetic studies on this species, which limits the knowledge available for use in breeding programs. The objective of this study was to estimate the relationship between cycle and production traits using canonical correlation analysis and to identify traits that can be used for the indirect selection of lima bean. The experiment was conducted at the Department of Plant Science of the Universidade Federal do Piauí, Teresina, in a randomized block design with five replications, in which 11 agronomic traits from six lima bean populations in the F3 generation originating from biparental crosses were evaluated in 2019. The data were subjected to canonical correlation analysis using the virtual environment R. The results showed that only the first coefficient of the canonical pair was significant (r = 0.5531) by the quisquare test, suggesting that the studied groups were not independent, as the cycle traits showed coefficients of large magnitudes in the relationship between groups. The canonical correlation results suggested that there is a linear association between cycle and production traits in lima beans, in which days to flowering, days to maturation, pod length, seed width, and seed thickness contribute the most to the association between groups.

ABSTRACT Compaction modifies the structural arrangement and essential functions of soil pores. In this context, the objective of this study was to evaluate the impact of different compaction levels in an Argissolo Amarelo (Ultisol) on the physical-hydraulic attributes that indicate the functionality of soil pores. The experiment was conducted using 0.05 x 0.05 m soil cylinders with 4 compaction levels (CL): 61, 71, 82 and 92%, and at each CL, the pore-size distribution, intrinsic soil air permeability (Kair), pore continuity index N, soil water characteristic curve and cumulative pore-size frequency were quantified under a completely randomized design. The increase in CL did not impact the amount of micropores, but reduced the amount of macropores to values lower than the minimum required from the CL of 82%. The increase in CL caused reductions in N index, Kair and aeration porosity, but with different amplitude depending on the CL and the water tension in the soil. CL above 61% reduced the water content at the tension range between 0 and 6 kPa and, as a consequence, increased the percentage of aeration pores, besides promoting greater water retention within the range between 10 and 1500 kPa. The evaluation of the physical-hydraulic attributes of the Argissolo Amarelo (Ultisol) revealed that the increase in the compaction level altered soil structure, reduced and formed pores that were poorly continuous and less permeable to air flow and, despite the higher water retention at the higher tensions, promoted lower available moisture content.

ABSTRACT Loss of genetic variability in natural populations affects negatively the adaptive and evolutive process of plant species. In this context, the objective of this work was to evaluate the existing genetic variability between and within natural populations of P. platycephala, using biometric characters of fruits and seeds and physiological characters of seeds and seedlings, and, thus, assess the potential for selection of mother trees, indicate areas for seed collection and use, and generate support for conservation and pre-breeding of plant species. A completely randomized experimental design was used, with 45 treatments (progenies) and four replications of 25 seeds. The progenies were evaluated in laboratory, using seeds collected from 45 mother trees sampled in three natural populations. The following characters were evaluated: seed germination percentage, germination speed index, and mean germination time; shoot and main root lengths; and seedling shoot and root dry weights. The data were subjected to RELM/BLUP analysis for estimating genetic parameters and correlations and to analyses of genetic divergence (UPGMA). The populations present genetic differences to each other and a significant variation between progenies for all characters evaluated, and the variation was greater within the populations. The characters evaluated present high genetic control; therefore, they can be used in analysis of genetic variability of populations and progenies of P. platycephala, thus assisting in the identification of areas for seed collection, conservation programs, and pre-breeding of the species.

ABSTRACT As a fresh food, sweet potatoes are highlighted for their taste and appearance. In the industry, they are valued for their starch and sugar content. In both scenarios, much attention has been given to the composition of bioactive compounds. The application of abiotic stresses seems to induce an overproduction of these compounds in some vegetables. The objective was to examine the influence of harvest time on the synthesis and accumulation of bioactive compounds in varieties of minimally processed sweet potatoes with different flesh colors. Sweet potato cultivars (Beterraba, Jerimum, Mãe de Família Roxa, and BRS Cuia) were harvested at 120, 150, and 180 days after planting, then subjected to minimal processing and stored at 5 ºC for 10 days. The most recommended time for harvesting sweet potatoes in semi-arid conditions for minimal processing by the industry is between 150 and 180 days. This is the period when the sweet potatoes exhibit the best quality for fresh consumption, as detected in ‘Mãe de Família Roxa’ and ‘Jerimum’. ‘BRS Cuia’ harvested at 120 days showed the highest phenolic compound levels, the highest polyphenol oxidase and peroxidase enzyme activities, and the most intense browning symptoms. In addition to its starch content, it can be used as a raw material for the extraction of phenolic compounds of interest. ‘Beterraba’ showed low sugar values, rendering them unfavorable for fresh consumption or minimal processing. However, this cultivar also exhibited a high content of carotenoids, making them bio-factories for the food and pharmaceutical industries.