ABSTRACT. This study aimed to present the advancements in different breeding stages of super sweet corn (SS), from heterotic field corn populations to the single-cross of SS. Two parental field corn populations, four backcrossed SS populations, four SS intervarietal hybrids (SS-IH), eighteen SS single hybrids (SS-SCH) and two controls were evaluated in two environments over two crop years. The SS-IH and SS-SCH categories presented the highest ear yield, and SS-SCH presented the highest ear yield without husk (11.3 t ha-1). Although SS-SCH was the most productive category, it presented the lowest husk coverage quality. The ear yield and husk cover traits expressed the highest heterosis based on the midparents. The hybrid genotype categories (SS-SCH, SS-IH and controls) had the greatest ear length and diameter, as well as plant and ear height. It was possible to conclude that the techniques used to exploit heterosis are efficient in increasing SS yield but not husk coverage, since this trait requires productive parents. Single-crosses, such as LCSH-116 x LP8HS-129 and LCSH-116 x LP8HS-130, stood out as promising genotypes for registration since they recorded high husk coverage yield and quality.

The success of sugarcane (Saccharum spp.) breeding programs depends on the choice of productive parent lines that have a high industrial yield and are genetically divergent. This study assessed the genetic divergence and population structure of sugarcane accessions that are the parents of the RB05 Series of the Sugarcane Breeding Program of Brazil. The DNA of 82 accessions was evaluated using 36 simple sequence repeat markers. The Jaccard similarity coefficient and Unweighted Pair Group Method with Arithmetic Mean clustering method were used to generate a cluster that was divided into 17 distinct groups derived from probabilistic models. The similarity coefficient used in both cases showed that the degree of similarity varied from 0.4716 (RB971551 x RB965586) to 0.9526 (RB936001 x SP89-1115), with a mean of 0.8536. This result demonstrates a high similarity between the 82 accessions and confirms Wright’s F statistic (0.125), which indicates moderate genetic variability. The less-similar crosses suggest that breeders seek a higher number of crosses using cultivar RB965586, highlighting the RB971551 x RB965586 and RB965586 x RB855511 crosses. The results demonstrate that crosses such as RB936001 x SP89-1115 and RB945954 x RB896342 should be avoided because of their high genetic similarity.

Grapevine trunk diseases are among the most important limiting factors of worldwide viticulture. In this context, we aimed to verify the effect of chemical fungicides, biological agents and plant extracts on the control of Lasiodiplodia theobromae in pruning wounds and their physiological effects in cv. Syrah grapevines. Plant extracts (clove, cinnamon, garlic, rosemary and lemongrass), commercial fungicides (difeconazole, tebuconazole, mancozeb, sulfur, pyraclostrobin, fosetyl-Al, and azoxystrobin), chitosan, Trichoderma harzianum and Bacillus subtilis were used for the in vitro trials. The protection of pruning wounds in the potted vines was studied using fosetyl-Al, tebuconazole, Trichoderma harzianum, Bacillus subtilis, garlic extract and clove extract. The experiments were carried out through two vegetative cycles: 2015/2016 and 2016/2017. The length of wood discoloration, pathogen re-isolation percentage, fresh mass of the pruning material, peroxidase activity, fluorescence, chlorophyll index, phenological stages, shoot length and leaf area were evaluated. The treatments with clove, garlic extract, tebuconazole, pyraclostrobin, mancozeb, fosetyl-Al and B. subtilis reduced mycelial growth by more than 90%. In the grapevines, the use of T. harzianum decreased the re-isolation of L. theobromae, but no differences were verified for the other plant evaluations. We concluded that the use of T. harzianum would be a potential option for wound protection without altering the physiological aspects of cv. Syrah grapevines.

The elucidation of the resistance mechanism of weeds to herbicides is important for management practices. The objective of this work was to investigate the resistance mechanism of glyphosate-resistant C. sumatrensis biotypes by determining the expression levels of the constitutive gene epsps and two ABC transport protein-coding genes designated m7 and m11 with RT-qPCR. Two biotypes of C. sumatrensis were evaluated: one resistant and one susceptible to glyphosate. The treatments consisted of the absence or application of two doses of glyphosate (1,080 and 8,640 g a.e. ha-1). Plant leaves were collected at 1 and 4 days after herbicide application. No difference was observed in epsps gene expression between the studied biotypes. The expression of the m7 and m11 genes revealed that both genes had higher relative expression in the resistant biotype with the application of glyphosate at both doses. The overexpression of the m7 and m11 genes in the resistant biotype treated with glyphosate reveals that these genes play a role in herbicide resistance. These genes may be involved in the sequestration of glyphosate into the vacuole lumen in the resistant C. sumatrensis biotype studied.

The forage palm is one of the main forages of ruminants in semiarid regions. Measurements of leaf area are required in agronomic studies because they are one of the main parameters used to evaluate plant growth. The objective of this study was to validate and define the best models for estimating the area and weight of Giant Sweet clone (Nopalea cochenillifera) forage cladodes in a non-destructive way based on the linear dimensions of length, width and thickness. There were 432 randomly measured cladodes at 550 days after planting. The length, width and thickness of each cladode were measured using a digital calliper. The cladodes were weighed individually. The cladode area was calculated by the gravimetric method. The power regression model was the most efficient method to explain the cladode area as a function of the product of length by width, while the gamma model was the most efficient method to explain the weight of cladodes as a function of the product of length by width and thickness. The power model,  and gamma model, = 0.536T + 0.028LW, were used to determine the area and weight of Nopalea cochenillifera Giant Sweet clone cladodes, respectively, based on the values of linear dimensions measured independently of the order of the cladode.

Strawberry is an economically and socially important crop in several regions worldwide. Thus, studies that provide information on topics in strawberry growth are important and must be constantly updated. The aims of this study were to fit a logistic growth model to describe strawberry fruit production and to estimate the partial derivatives of the fitted model in order to estimate and interpret the critical points, in addition to using multivariate analyses. To do this, data on 16 treatments [combinations of two cultivars (Albion and Camarosa), two origins (national and imported), and four mixed organic substrates (70% crushed sugar cane residue + 30% organic compost, 70% crushed sugar cane residue + 30% commercial substrate, 70% burnt rice husk + 30% organic compost, and 70% burnt rice husk + 30% commercial substrate)] conducted in a randomized complete block design (RCBD) with four replicates were used. A logistic model was fitted to the accumulated fruit production stratified by treatment and replication. Partial derivatives related to the accumulated thermal sum were estimated in order to quantify the critical points of the model. Subsequently, a principal component analysis was performed. The results show that the use of growth models substantially increases the inferences that can be made about crop growth, and the multivariate analysis summarizes this information, simplifying its interpretation. Approaches such as those carried out in this study are still rarely used, but, compared to simpler models, they increase the amount of inferences that can be made and provide greater elucidation of the results.

In addition to the agronomic traits of interest, soybean cultivars destined for human consumption must have specific attributes that meet the demands of the consumer market. To meet this demand, this study aimed to select progenies with agronomic and commercial traits of interest from soybean populations obtained from crosses between different food and grain genotypes and to estimate the genetic parameters of these populations. The F3:4 and F4:5 progenies that originated from the two crosses were evaluated in the 2015/16 and 2016/17 agricultural years, respectively, using the pedigree method. The experimental design utilized augmented blocks, while statistical analyses were performed by using the REML/BLUP methodology. The evaluated traits were plant height at maturity (APM), insertion height of first pod (AIV), lodging (AC), agronomic value (VA), number of pods per plant (NV), number of days to maturity (NDM), number of branches (NR), number of nodes (NN), 100-seed weight (PCS), and grain yield per plant (PG). The best progenies were selected, and the following genetic parameters were estimated: genetic variance, phenotypic variance, heritability, and selective accuracy. The estimates of the genetic parameters indicate the presence of high genetic variance in these populations. Heritability was high for most of the traits, indicating good potential for the selection of superior genotypes.

Strawberries are berry-type fruits that are very popular and widely consumed all over the world. The sensorial, physical-chemical and nutritional characteristics of strawberries are parameters of quality that influence the choices of consumers. However, these characteristics may be influenced by intrinsic and extrinsic factors that alter the fruit quality. The concentrations of nutrients and other chemical compounds in strawberries may increase and/or decrease according to the cropping system, maturation stage, climatic conditions, and preservation and storage methods. Factors characteristic of the cultivar, such as the genetic profile, may also influence the composition of strawberries. In this context, the objective of this research was to evaluate the sensorial, physical-chemical and nutritional characteristics of different strawberry cultivars to identify the genotype(s) with the best characteristics for commercialization and human consumption. The day-neutral strawberry cultivar "Aromas" and short-day strawberry cultivars "Camarosa, Camino Real, Dover, Sweet Charlie, and Tudla" were cultivated in the Olericultura Sector of the State University of the Midwest (UNICENTRO), Paraná State, Brazil. The fruits were characterized in relation to their physical-chemical, nutritional and sensorial aspects. According to the sensorial profiles, the Camarosa, Camino Real, Dover, and Tudla genotypes showed greater acceptability among consumers. Camarosa, Sweet Charlie, and Tudla presented better physical-chemical characteristics for human consumption, while the cultivars Camarosa, Dover, and Tudla had the best nutritional contents. In general, it is concluded that the genotypes Camarosa and Tudla are the most favourable for human consumption, according to their sensorial, physical-chemical and nutritional characteristics.

The objective of this work was to evaluate the response of sunflower cultivars submitted to increasing levels of phosphate fertilization in two crops. The experimental design was a randomized complete block design with four replicates in subdivided plots, where five doses of simple superphosphate (0, 50, 100, 150, and 200 kg ha-1 P2O5) were allocated to the plots and three sunflower cultivars (Aguará 06, Altis 99, and Embrapa 122-V2000) were assigned to the subplots. The variables evaluated were the P content in the diagnostic leaf, number of achenes per capitulum, achene yield (kg ha-1), oil content (%) and oil yield. The phosphorus doses increased the components of production. The dose that provided the best sunflower performance varied for the different cultivars. Among the doses studied, fertilization with 100 kg ha-1 P2O5 in the 2016 agricultural crop and 150 kg ha-1 P2O5 in the 2017 agricultural crop provided the best conditions for sunflower cultivation. The cultivar Aguará 06 produced more achenes and oil than the other cultivars analyzed in the agricultural crops.

Tissue culture techniques have been employed for bromeliad mass propagation by means of the morphogenetic route of nodular cluster cultures (NCs). This study aimed to assess protein, carbohydrate and global DNA methylation (GDM) level dynamics during NCs induction from Vriesea reitzii seeds. Seeds were inoculated into Murashige and Skoog (MS) liquid medium supplemented with 4 µM α-naphthaleneacetic acid (NAA) to induce NCs and in culture medium without plant growth regulators to form normal seedlings. Samples collected at 0, 3, 7, 10, 14, and 21 days of culture were analyzed. All parameters assessed showed the same variation pattern. However, seeds inducing NCs showed significantly lower starch (6.0 mg g-1 FM), carbohydrate (10.7 mg g-1 FM) and GDM (11.0%) levels than seeds forming normal seedlings after 21 days in culture. On the other hand, the protein content (9.1 mg g-1 FM) was significantly higher during induction. NCs induction process through seeds is the result of gene reprogramming in the explant, which leads to morphological, biochemical and metabolic alterations. This involves dedifferentiation, high cell proliferation, high energy demand and protein synthesis, which is related to elevated metabolic activity.