Psidium cattleyanum, commonly known as araçá, is a fruit tree valued for its nutritional benefits and is increasingly consumed fresh and processed. However, the genetic variability within its populations makes selecting and propagating individuals with desirable traits challenging. This study aimed to optimize the in vitro shoot regeneration from axillary buds of Irapuã and Ya-cy cultivars using a complete MS culture medium and half-strength MS basal salts (MS/2), supplemented with 6-benzylaminopurine (BAP). Apical shoots from in vitro germinated plantlets were placed on MS or MS/2 medium, supplemented with 2.2, 4.4, or 8.8 µM BAP, and a control without BAP. For the Irapuã cultivar, the highest shoot regeneration rate was achieved on MS/2 medium with 2.2 µM BAP during the third subculture, resulting in 100% of the explants producing shoots. In contrast, the Ya-cy cultivar showed the best results on MS/2 medium with 4.4 µM BAP, yielding up to 78.3% shoot formation in the first subculture. Both cultivars were rooted on MS/2 culture medium without plant growth regulators, with cv. Irapuã achieving up to 100% rooting and cv. Ya-cy 41.2%. A micropropagation protocol was successfully developed for the Irapuã and Ya-cy cultivars.

Actinocephalus polyanthus (bong.) Sano (Eriocaulaceae) is an everlasting endemic endemic to Brazil with great potential for use in landscaping and as a cut flower on the national and international markets. In order to ensure that its use as an ornamental plant does not jeopardise populations of the species in areas of natural occurrence, as well as to avoid predatory extraction, the development of protocols for its propagation is extremely important. However, no protocol for the in vitro propagation of Actinocephalus polyanthus has been reported in the literature. The aim of this study was to establish a protocol for the germination, seedling development and acclimatization of A. polyanthus. The use of Wood plant medium culture medium at concentrations of 75 and 100% proved to be the most effective for germinating the seeds, but it was not the best medium for growing the seedlings, given that for the growth phase the medium was MS at the highest concentrations, also 75 and 100% salt concentrations, for acclimatization the use of a shading screen proved to be the most effective and the use of washed sand or carolina soil were the best substrates.

ABSTRACT The objective of this work was to monitor coffee plants (Coffea arabica L.) after pruning through multispectral images obtained with an unmanned aerial vehicle (UAV) containing a Mapir Survey 3 camera and estimate agronomic parameters based on simple regression parametric models. Growth evaluation was performed in 228 sampling points related to the coffee plants. The parameters analyzed were plant height, crown diameter, plagiotropic branch length, and the number of plagiotropic branches after the pruning point. The creation of mosaics was performed through the software Agisoft PhotoScan Professional 1.4.5, and radiometric calibration through Mapir Camera Control, georeferenced by QGIS and normalized by ENVI. Based on the models generated, data analysis permitted estimating coffee plants’ agronomic parameters after decote-type pruning (cutting off the orthotropic branch at 1.5 m and 2.0 m above ground) with high accuracy. Height was measured in April’s flight with the near-infrared band (Precision = 91.87%), crown diameter and plagiotropic branches length in April’s flight with the infrared band (Precision = 89.36% and 82.22%, respectively), number of nodes in February’s flight with the near-infrared band (Precision = 79.48%), and the number of plagiotropic branches after the pruning point in June’s flight with the near-infrared band (Precision = 69.57%).

ABSTRACT Maize landraces diversity is important for many smallholder and indigenous populations. Gene flow constitutes a threat to the genetic conservation of several locally adapted maize landraces and, risk management depends on monitoring transgenic occurrence in non-GM maize. This study evaluated the occurrence of exogenous proteins from GM-maize in maize landraces and teosinte cultivated in the Alto Jequitinhonha region, State of Minas Gerais. Gene flow from GM maize to non-transgenic varieties was evaluated in eight maize groups and one teosinte variety. A transgenic maize variety was used as a positive control. Proteins Cry1F and Cry2Ab2 were monitored using the Protein Detection Assay kit (Envirologix QuickStix® kit protocols for detecting Cry1F and Cry2Ab2 proteins). Transgenic proteins were not detected in the leaves of landraces and teosinte cultivated in the Alto Jequitinhonha region.

ABSTRACT The use of corn hybrids adapted to the soil and climate conditions of the cultivation region under adequate optimum plant density is a determining factor for the maximization of grain yield. In this sense, the objective was to evaluate the productivity of corn hybrids under two sowing densities during the 2020/21 crop season in the medium-high Uruguay region of the state of Rio Grande do Sul. The corn hybrids AS1555 PRO3, B2401 PWU, B2418 VYHR, B2612 PWU, BG7061 YHR, DKB235 PRO3, NS45 VIP3, NS73 VIP3, NS80 VIP3, P2501, P3016 VYHR, P3565 PWU and 30F53 VYHR were submitted to densities of 66,667 and 88,889 plants ha-1, in a randomized block design with ten replications. Corn hybrids showed superior grain yield when subjected to the density of 88,889 plants ha-1 in the medium-high Uruguay region of Rio Grande do Sul, surpassing in most cases the state and national average yield of harvest 2020/21. Most of the corn hybrids used present potential for cultivation at higher sowing density than their respective recommendations. Considering the superior productivity of hybrids NS80 VIP3, B2401 PWU and NS73 VIP3, their cultivation under conditions similar to those of the study is recommended.

This study aimed to establish production curves of cuttings for Coffea canephora coffee plants in response to nitrogen doses. A clonal garden of the botanical variety Robusta was used to evaluate the effects of seven nitrogen doses divided into four applications. The subplots corresponded to two evaluation periods: January and June 2019. The following traits were evaluated: number of stems, number of viable cuttings, number of cuttings per stem, cutting fresh and dry mass, and cutting macronutrient contents. The results showed that C. canephora produced a higher amount of vegetative mass and propagules during the period from September to January compared to the period from January to June. Nutrient concentrations in the tissues varied with the period of the year due to soil nutrient availability and the amount of accumulated dry mass. Increasing nitrogen doses resulted in higher vegetative and propagules mass associated to higher nitrogen and potassium concentrations in the cuttings; but had no effect on phosphorus, calcium, magnesium, and sulfur contents. Nutrient contents in the cuttings followed the order K>N>Ca>P>Mg>S regardless of the applied nitrogen dose.

ABSTRACT Climate change has made food security vulnerable. Therefore, it is important to have discussions on the subject and take actions that minimize the environmental impacts on family farming, that will be directly or indirectly affected by climatic events. With this in mind, this study aimed to identify climate changes in the state of Piauí based on climate projections and to verify their possible impacts on the suitability of growing food crops, such as beans, corn, cassava, and cashew. The climate scenarios analyzed were 2011–2040, 2041–2070, and 2071–2100. The observed data on current climate came from the National Institute of Meteorology (INMET), and future climate projections came from the Brazilian Portal of Climate Projections of the National Institute for Space Research (INPE). Based on the climatic data obtained (current and future), the climatological water balance was calculated, using the method proposed by Thorntwaite, with consecutive characterization of the suitability for crops. All maps were generated in QGIS. According to the results, crops that may suffer from water deficit are beans and cashews. The latter, in the RCP 8.5 scenario (2071–2100) shows unsuitability for cultivation throughout the state. The population with the highest rate of social vulnerability is the one that will be most damaged by the events caused by climate change.

The objective of this work was to characterize reference bacteria strains, belonging to the genus Bacillus and species of correlated genera, by simplified morphological and biochemical methods. The morphological characterization is based on the aspects of the colonies, as well as cytomorphology of the species, by optical and scanning microscopy. For biochemical characterization, the sensitivity test to antimicrobials by disk-diffusion is performed. Moreover, the strains were characterized by extracting intracellular proteins. Characteristics such as shape, color, and consistency of the colonies, in addition to the type of spore and production of protein crystals were determinants for the morphological characterization of these species. The antibiogram revealed high resistance to β-lactam group antibiotics, in species of Bacillus cereus s.l group. In Bacillus subtilis s.l. group there was high susceptibility to antibiograms, mainly for species of B. subtilis. The protein profile provided specific protein patterns for some species, mainly bands of 130 e 65 kDa for B. thuringiensis, 140 e 130 kDa for Lysinibacillus sphaericus, and 115 kDa for Brevibacillus laterosporus. Our results showed that the morphological and biochemical characterizations, provided a simple identification, with easy interpretation, and low cost.

Species of the Amaranthus genus are very versatile and have potential for the application in the development of commercial products. The near infrared spectroscopy (NIR) is an efficient tool that can help in the quality control of products, quickly and non-destructive to the sample. The goal of this study was to carry out the distinction of seed and oils of different Amaranthus species using the near infrared spectroscopy. Three species were used: A. viridis L., A. hybridus L. e Amaranthus sp. (commercial). The spectra acquired from the sample using the near infrared spectroscopy were submitted to the partial least squares discriminant analysis (PLS-DA) and to the principal component analysis (PCA). Through PCA, it was possible to differentiate the Amaranthus species both for seeds and oils. Through PLS-DA, it was possible to predict the classes of the species with high degree of correct classification, with 96.67% of correct classifications for seeds and 98.89% for oil. Thus, with the use of the near infrared spectroscopy associated with the multivariate statistical analysis, it is possible to classify the different Amaranthus species, especially when using the oil.