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Abstract Diatomaceous earth is an organic naturally occurring material rich in silicon. This silicon source can be used in organic agriculture, it also has a great potential of use in the acclimatization of crops. However, there are no reports of the effects of diatomaceous earth supplementation on the micropropagation of sweet potato. Thus, the objective of this study was to evaluate the effects of different concentrations of diatomaceous earth applied in vitro on the growth, physiology and anatomy of sweet potato cv. ‘Brazlândia Branca’ after acclimatization. Four concentrations of diatomaceous earth. After 30 days of in vitro growth, the plants were transferred to a greenhouse for acclimatization. After 45 days, leaf number, shoot and root length, fresh and dry shoot and root mass, gas exchange, chlorophyll content, root and leaf anatomy. The experimental design was completely randomized. The supplementation of diatomaceous earth in the in vitro cultivation had beneficial effects, increasing the accumulation of mass, improving the photosynthetic apparatus and promoting favorable anatomical characteristics during the acclimatization of the sweet potato plants. In addition, the use of diatomaceous earth achieved adequate seedling development, with higher seedling quality and resistance to biotic and abiotic effects than attained with control treatment.

A qualidade luminosa é um fator importante para a adequação da produção de plantas através da cultura de tecidos vegetais, pois interfere diretamente nos processos de morfogênese e na capacidade fotossintéticas dos explantes. O objetivo deste estudo foi analisar o impacto de luzes monocromática do tipo diodo emissor de luz (light-emitting diode - LED) no desenvolvimento in vitro de Cattleya walkeriana G. e os efeitos na fase aclimatização. As plantas foram desenvolvidas in vitro sob as cores de luzes do tipo LED verde, azul, amarelo, vermelho, 2 vermelhos : 1 azul, e branco. Para cultivo in vitro foi utilizado o meio Knudson acrescido de 20 mg L-1 de sacarose, 5,5 mg L-1 de ágar, 2% de carvão ativado, 100 mL de água de coco, e pH 6,0. Para o cultivo ex vitro as plantas foram aclimatizadas em bandejas de isopor contendo esfagno como substrato. De maneira geral, os comprimentos luminosos fornecidos apresentaram impactos nas análises de crescimento in vitro e na de aclimatização. Houve influência na espessura da cutícula das plantas in vitro. Os teores de clorofilas e carotenoides não foram significativos. Podemos concluir, que comprimentos luminosos formados pelos LEDs 2 vermelhos : 1 azul, vermelho e amarelo podem ser indicados para melhor desempenho na produção de C. walkeriana. Os LEDs 2 vermelhos : 1 azul, e o LED vermelho propiciam desenvolvimento in vitro superior ao demais com ganhos na fase de aclimatização para espécie. O LED amarelo propiciou um possível processo de rustificação in vitro o que garantiu o maior sucesso das mudas no período de aclimatização.

ABSTRACT: Effective protocols for in vitro rooting for woody fruit trees are still a challenge for in vitro seedling production, especially when there is a need to insert new cultivars or rootstocks. These protocols are essential to accelerate studies in plant breeding programs and for seedling distribution. This study evaluated the use of 6-Benzylaminopurine (IBA) in in vitro rooting of Pyruscomunnis rootstocks, clones ‘OHxF87’ and Pyrodwarf. Explant exposure times (0, 24, 48, 72, and 96 hours) to 20 mg L-1 IBA were tested for in vitro rooting. The exposure to IBA resulted in rooting rates above 80%, surpassing some results reported in the literature. The 24-hour treatment provided 81,81% survival, leading to an average growth of five roots with 19 mm length, for ‘OHxF87’ rootstock. The same exposure time resulted in the highest survival rate (75%) and the highest mean root number, seven roots per plant with 10 mm length, for ‘PDW’ rootstock. Root formation did not occur in the absence of synthetic auxin. Therefore, it can be concluded that a 24-hour exposure at 20 mg L-1 IBA was sufficient to promote in vitro rooting in ‘OHxF87’ and Pyrodwarf rootstocks’.

A floração in vitro é uma técnica utilizada no melhoramento genético que acelerar gerações e favorecer a fixação mais rápida de novos caracteres de interesse agronômico e do mercado. O estudo visou estabelecer um protocolo para a floração in vitro de Den- drobium nobile, através dos efeitos combinados de temperatura e do regulador de crescimento thidiazuron (TDZ). Os experimentos foram realizados em incubadora tipo BOD a 18, 21, 24 °C e, em sala de crescimento a 26 °C. As concentrações de TDZ testadas foram de 0,0, 0,5, 1,0 e 2,0 mg L-1. A maior porcentagem de brotos floridos de 13,70% ocorreu na concentração de 2 mg L-1 de TDZ cultivados em temperatura de 18 °C. O florescimento in vitro de D. nobile foi promovido em plantas cultivadas em ½ MS suplementadas com 30 g L-1 de sacarose, 5,5 g L-1 de ágar, 100 mL L-1 de água de coco, pH 6,0 e 2,0 mg L-1 de TDZ em tempera- tura controlada de 18 °C e fotoperíodo de 16 h. O protocolo de indução de florescimento in vitro da espécie D. nobile poderá ser utilizado ou aprimorado para estudos futuros.

IntroductionThe bad management of organic waste negatively affects environmental quality and composting has been a viable recycling alternative. Microorganisms are responsible for waste degradation during the composting process and, consequently, for transforming this waste into natural fertilizer. This work aimed to analyze and identify the biodiversity of yeasts and filamentous fungi throughout a composting process based on organic residues under different treatments (commercial inoculum, non-commercial inoculum, and control treatment) and to investigate the enzymatic activity of these microorganisms.MethodsMicroorganisms were isolated and identified from samples at 0, 5, 10, 20, 40, 60, and 120 days. Filamentous fungi were identified according to their macroscopic and microscopic characteristics, and yeasts were identified by sequencing the 18S rDNA region. All identified strains were evaluated for ligninolytic, cellulolytic, hemicellulolytic, amylolytic, pectinolytic, proteolytic, lipolytic, and ammonification. During the composting phases, the filamentous fungi were higher than the yeast population.Results and discussionAt the beginning of the process, a higher species diversity was observed, and the population of yeasts and filamentous fungi was, on average, 6.50 log CFU g−1. The microbial communities were similar throughout the process in the two inoculated treatments, which showed more significant microbial activity, diversity, and efficiency in the transformation of organic matter, and consequently, advantages in terms of the final product quality compared to the control treatment. The yeasts Pichia kudriavzevii, Pichia farinosa, Issatchenkia orientalis, and the filamentous fungi of the genus Aspergillus spp. proved to have high biotechnological value and could be used as starter cultures to accelerate the composting process.

Abstract To produce pitaya (Hylocereus spp.), it is essential that pollination occur, either artificially or by pollinating agents. This study evaluated the viability of self-pollination, cross-pollination, and natural pollination, as well as pollen viability, stigma receptivity and ideal pollination window in pitaya flowers (Hylocereus spp.). An experiment was conducted with a randomized block design consisting of four treatments: T1: manual self-pollination; T2: nocturnal open pollination; T3: diurnal open pollination; and T4: manual cross-pollination - red-fleshed pitaya [ Hylocereus polyrhizus] pollen placed on white-fleshed pitaya [ Hylocereus undatus] stigma. The experiment had four replicates, with two plants per replicate (two flowers per plant), totaling 16 flowers per treatment. The analyzed variables were fruit weight, length, diameter, titratable acidity, pH, soluble solids, and SS/TA ratio; the germination percentage of pollen grains; and the receptivity of stigmas. Artificial pollination (self- and cross-pollination) of white-fleshed pitaya (Hylocereus undatus) is viable, resulting in larger fruits than natural pollination, with cross-pollination being the most recommended. Throughout the floral opening period, the pitaya flower (Hylocereus spp.) has receptive stigma capable of receiving pollen. The flowers exhibit the highest pollen germination rate at 7 p.m, which is the ideal pollination window for pitaya.

Currently, southern Minas Gerais (MG) state is an important producer of different olive tree (Olea europaea L.) cultivars because, in this region, the plants can differentiate the buds to produce flowers and fruit. To stimulate the rooting of cuttings, the synthetic hormone indole-3-butyric acid (IBA) at a concentration of 3 g L−1 is used commercially. However, few studies have investigated arbuscular mycorrhizal fungi (AMF), isolated or combined with rhizobacteria, as a biotechnological tool to produce hormones that function in the rooting of olive tree cuttings. The aim of this study was to evaluate the capacity of different AMF species (Rhizophagus clarus, Gigaspora rosea, or Acaulospora scrobiculata), combined or not with IBA or rhizobacteria, to promote the rooting of three olive tree cuttings (Arbequina, Grappolo 541, and Maria da Fé) with potential for cultivation in this region. For this, three experiments were conducted at the Experimental Farm of EPAMIG in Maria da Fé (MG), and the rooting potential of the olive tree cuttings inoculated with I) AMF, II) AMF combined with increasing doses of IBA, and III) AMF combined with three isolates of rhizobacteria was evaluated. The inoculation of olive tree cuttings of cultivars Arbequina, Grappolo 541, and Maria da Fé with Rhizophagus clarus, Gigaspora rosea, or Acaulospora scrobiculata combined or not with IBA or rhizobacteria did not significantly promote rooting. Alternative forms of rooting olive tree cuttings are still a challenge, and further studies for standardizing methodologies and experimental conditions are required.

Organic wastes are considered the most significant components of urban solid waste, negatively affecting the environment. It is essential to use renewable resources to minimize environmental risks. Composting is one of the most sustainable methods for managing organic waste and involves transforming organic matter into a stable and nutrient-enriched biofertilizer, through the succession of microbial populations into a stabilized product. This work aimed to evaluate the efficiency of the new type of composter and the microbial and physiochemical dynamics during composting aiming to accelerate the degradation of organic waste and produce high-quality compost. Two inoculants were evaluated: (1) efficient microorganisms (EM); (2) commercial inoculum (CI), which were compared to a control treatment, without inoculation. Composting was performed by mixing organic waste from gardening with residues from the University's Restaurant (C/N ratio 30:1). The composting process was carried out in a 1 m3 composter with controlled temperature and aeration. The thermophilic phase for all treatments was reached on the second day. Mature compost was obtained after an average of 120 days, and composting in all treatments showed an increase in the availability of P and micronutrients. The new composter helped to accelerate the decomposition of residues, through the maintenance of adequate oxygen content and temperature control inside the cells, providing high metabolic activity of microorganisms, contributing to an increase in physicochemical characteristics, also reducing the composting time in both treatments. During composting, the bacteria and actinobacteria populations were higher than yeasts and filamentous fungi. The inoculated treatments presented advantages showing more significant mineralization of P-available and micronutrients such as Mn and Zn in terms of the quality of the final product in comparison to the control treatment. Finally, the new composter and the addition of inoculants contributed significantly to the efficiency of the process of composting organic waste.

The objective of this work was to carry out the in vitro establishment of Echynochloa polystachya aiming at obtaining a micropropagation protocol for works involving the selection of superior genotypes and the cultivation of the species. E. polystachya stems were collected in the municipality of Manaus-AM. Explants were inoculated in test tubes containing Murashige and Skoog (MS) medium. Thirty days after in vitro establishment, the rate of sprouting and contamination were evaluated. Experiments were also carried out to assess the effects of sucrose and 6-benzylaminopurine (BAP) concentrations on the tillering rate of explants. It was found that during the successive subcultures there was a decrease in internodes and the consequent loss of vigor. There were responses in the multiplication rate at concentrations starting from 45 g L-1 sucrose. In addition, BAP and sucrose interfered the development and in vitro multiplication. Sucrose in conjunction with BAP was harmful and shortened internodes. The physiological state of the explants for the species under study was intrinsically linked to the concentrations of sucrose used for the culture medium and the concentrations of BAP. However, the sucrose and BAP concentrations suggested for in vitro cultivation of E. Polystachya must be adjusted during successive subcultures. Absence of contamination in the in vitro establishment occurred at concentrations 15, 30 and 60 g L-1 sucrose. The combination of 1.5 mg L-1 BAP and 30 g L-1 sucrose promoted greater induction of sprouts. In addition, the in vitro rooting of E. polystachya was 45%.

Many important crops have cultivars with different ploidy and provide a diverse choice of materials for breeding programs. Therefore, it is essential to accurately assess the ploidy of all breeding materials. Increased DNA content is known to have various effects on external and internal morphology, an effect known as the “nucleotypic effect”. Thus, anatomical assessment can be used as a tool for determining ploidy in plants, making the chromosome counting technique or flow cytometry unnecessary. This study aimed to evaluate the leaf anatomical characteristics of banana cultivars and understand the relationship between these features and ploidy levels. Thirteen accessions were evaluated, including diploid, triploid, and tetraploid genotypes, and cultivars, resulting from in vitro propagation after 90 days of acclimatization. Five fully expanded young leaves were collected from each cultivar, fixed in FAA70 (formaldehyde–acetic acid–ethanol) and preserved in 70% alcohol. Transverse and paradermal sections of the abaxial and adaxial regions were taken, and variables such as size and stomatal density, leaf thickness in the midrib and fourth vascular bundle region, and thickness of the epidermis, hypodermis, and parenchyma were measured. Results for leaf thickness, stomatal size, and density proved to be appropriate parameters for characterizing banana ploidy levels.

Dynamic laser speckle (DLS) analysis is a very sensitive technique to measure biological activity within samples. In agriculture, the technique is applied to monitor seed germination, but external light, water content, and pigments affect the measurements. DLS systems use visible light sources, typically red lasers, which may exacerbate their influences. The main objective of this work is to assess whether infrared (IR) lasers improve the robustness of DLS measurements in seed germination applications. We develop a system where DLS analysis can be performed simultaneously on visible and IR light. Using the system, we quantify how the DLS signal is affected by pigments and scattering. The results show that the use of IR light reduces the variability of the measurements acquired. DLS systems based on IR light appear to be less sensitive to pigments, and the greater penetration of IR light into samples, which is due to reduced scattering, may contribute to the signal collected being correlated to relevant biological processes within the inner tissue. Additionally, water activity provides less influence on the DLS signal when an IR laser is used. These findings support the wider use of IR lasers in DLS-based instruments for applications in biological samples.

Phosphorus (P) is one of the essential macronutrients for plant growth, being a highly required resource to improve the productive performance of several crops, especially in highly weathered soils. However, a large part of the nutrients applied in the form of fertilizers becomes “inert” in the medium term and cannot be assimilated by plants. Rationalizing the use of phosphorus is a matter of extreme importance for environmental sustainability and socioeconomic development. Therefore, alternatives to the management of this nutrient are needed, and the use of P-solubilizing microorganisms is an option to optimize its use by crops, allowing the exploration of less available fractions of the nutrient in soils and reducing the demand for phosphate fertilizers. The objective of this study is to discuss the importance of phosphorus and how microorganisms can intermediate its sustainable use in agriculture. In this review study, we present several studies about the role of microorganisms as phosphorus mobilizers in the soil. We describe the importance of the nutrient for the plants and the main problems related to the unsustainable exploitation of its natural reserves and the use of chemical fertilizers. Mainly we highlight how microorganisms constitute a fundamental resource for the release of the inert portion of the nutrient, where we describe several mechanisms of solubilization and mineralization. We also discussed the benefits that the inoculation of P-solubilizing microorganisms provides to crops as well as practices of using them as bioinoculants. The use of microorganisms as inoculants is a viable resource for the future of sustainable agriculture, mainly because its application can significantly reduce the application of P and, consequently, reduce the exploitation of phosphorus and its reserves. In addition, new research must be conducted for the development of new technologies, prospecting new biological products, and improvement of management practices that allow for higher efficiency in the use of phosphorus in agriculture.

Abstract The objective of this work was to investigate the effect of plant growth regulators (PGR) on the induction of calli from cotyledons of Enterolobium contortisiliquum grown in vitro, as well as to evaluate the inhibitory activity of trypsin in these calli. Cotyledons of E. contortisiliquum were cultivated in culture medium supplemented with dichlorophenoxyacetic acid (2,4-D), picloram (PIC), kinetin (KIN), and 6-benzylaminopurine (BAP). Callus mass, inhibitory activity of trypsin, morphogenetic and cytochemical observations, and biological activity were measured after 60 days. The Pareto diagram showed that only 0.5 mg L-1 PIC influenced the increase of fresh mass, whereas 0.5 mg L-1 BAP influenced dry mass. The principal component analysis plot showed the formation of two clear clusters. The inhibitory activity of trypsin is achieved at a higher intensity in the treatment with 0.5 mg L-1 2,4-D + 2.0 mg L-1 PIC + 0.5 mg L-1 KIN + 2.0 mg L-1 BAP. The combination of PGR at different rates causes an intense callus formation. Low concentrations of PGR result in a higher fresh mass, dry mass, and biological activity. The use of PGR is efficient in obtaining E. contortisiliquum calli with a satisfactory inhibitory activity of trypsin.

Abstract The objective of this work was to evaluate the viability of the micrografting of yellow dragon fruit (Selenicereus megalanthus) on different rootstocks, based on DNA content and anatomical analyses. The used rootstocks were: yellow dragon fruit, white dragon fruit (Hylocereus undatus), Saborosa (Selenicereus setaceus) dragon fruit, and the Cebra and Orejona red dragon fruit (Hylocereus polyrhizus) varieties. The experimental design was completely randomized with five treatments and four replicates of five plants. After 30 days of cultivation, the following traits were evaluated: length and diameter of the micrografts and microrootstocks; and root length, percentage of setting, and fresh mass of the micrografts. Flow cytometry analyzes were performed before and after micrografting to verify genetic stability and the occurrence of endoreduplication. In addition, histological sections were made in the micrografting region to verify the connections of vessels and tissues between the graft and the rootstock. Endoreduplication was observed in all treatments. The amount of DNA in the yellow dragon fruit micrograft increased on the red Orejona variety. The presence of vessel connections was verified between the micrografts and microrootstocks. The yellow dragon fruit was also more vigorous when grafted on Orejona. Based on DNA content and anatomical analyses, in vitro yellow dragon fruit micrografting is feasible in all used rootstocks.

Based on the concepts of circular economy and bioeconomy, the reuse of agrifood residues through vermicomposting can help solve serious environmental problems such as soil contamination and degradation, erosion and climate change. In this sense, the objective was to identify, quantify and analyze the physical, chemical, hormonal, amino acid content and microbial biodiversity of three formulations of vermicompost, with and without inoculation of microorganisms from native forest and commercial formulation, aiming at the production of an organic fertilizer rich in microorganisms for use in sustainable production systems. As a result, the vermicompost formulations presented values higher than the minimum requirements stipulated by Brazilian legislation for the registration of class A composite organic fertilizer. There is a significant difference between the vermicomposts, in the parameters related to the content of phosphorus, auxin, tryptophan and organic matter, as well as the relation between humic and fulvic acids. Bacillus sp. and Trichoderma sp. were also influenced by the type of vermicompost formulation. In addition, inoculation with microorganisms from native forest promoted an increase in biodiversity, in which the presence of Actinomyces sp. and Azotobacter chrooccocum contribute to the reduction in the levels of heavy metals in the compost. It is concluded that vermicomposting is a potential tool in the reuse of agri-food residues, with expressive microbial diversity that can influence plant growth, suppression of pathogens, minimize or reduce the effects of biotic and abiotic stresses on plant production, in addition to contributing to maintenance of soil biodiversity, integral fertility and resilience to climate change.

Strawberry (Fragaria x ananassa, Duch.) is an important crop worldwide. However, since it is a highly demanding crop in terms of the chemical conditions of the substrate, a large part of strawberry production implies the application of large amounts of fertilizers in the production fields. This practice can cause environmental problems, in addition to increases in the fruit’s production costs. In this context, applying plant growth-promoting bacteria in production fields can be an essential strategy, especially thanks to their ability to stimulate plant growth via different mechanisms. Therefore, this study aimed to test in vitro and in vivo the potential of bacteria isolated from strawberry leaves and roots to directly promote plant growth. The isolates were tested in vitro for their ability to produce auxins, solubilize phosphate and fix nitrogen. Isolates selected in vitro were tested on strawberry plants to promote plant growth and increase the accumulation of nitrogen and phosphorus in the leaves. The tested isolates showed an effect on plant growth according to biometric parameters. Among the tested isolates, more expressive results for the studied variables were observed with the inoculation of the isolate MET12M2, belonging to the species Brevibacillus fluminis. In general, bacterial inoculation induced strain-dependent effects on strawberry growth. In vitro and in vivo assays showed the potential use of the B. fluminis MET12M2 isolate as a growth promoter for strawberries.

Growth-promoting bacteria are already used in sustainable agricultural systems in Brazil. The market is dominated by inoculants and biological pesticides, which do not reach the full potential of this tool in the agricultural sector. This study aimed to evaluate four bacterial strains for the presence of growth promotion mechanisms, as well as the reduction of Asian rust severity in soybean plants and its effects on three antioxidant enzymes during pathogenesis. The plants were treated using the bacterial cells and/or their biosurfactants before inoculation of the pathogen (IOP). Severity was measured based on a diagrammatic scale at 14, 18 and 21 days after IOP, and the activities of the enzymes SOD, CAT, and APX were evaluated 21 days after IOP. Treatments containing only bacterial cells were not efficient in reducing the severity, with losses of leaf area reaching 15%, while the addition of biosurfactants led to a result that is similar to the biofungicide, based on Bacillus subtilis (Serenade®). The presence of direct growth promotion mechanisms can be observed in all isolates, as well as the role of bacterial metabolites, especially lipopeptides, in the biological control of diseases and the modulation of the plant’s immune response.

Breeding programs for improvement of sacha-inchi, Plukenetia volubilis L., generally aim to select individuals with greater seed yield since there is a strong correlation between seed yield and oil production. However, the manual removal of seed husks for evaluating this trait is laborious and costly, thereby discouraging breeding efforts. Accordingly, the objective of the present study was to estimate gains from indirect selection of seed production in sacha-inchi progenies, focusing on maximizing efficiency in improvement programs. Genetic parameters along with direct and indirect selection gains were estimated for seed yield traits in 12 open-pollinated progenies. Strong genetic correlations were observed between total number of fruits (TNF), total weight of fruits (TWF), and total weight of seeds (TWS) per plant (r > 0.96). Notably, all three traits demonstrated high heritability (h2 > 0.81). Therefore, plants with high TNF and TWF (Cuzco, Dos de Mayo, Shanao, Aucaloma, and AM-7) can be used to indirectly select the genetic traits of higher seed yields (GS% = 23%). Genetic gain for dry seed production with a selection index of 42% was estimated at 23%, which corresponds to 118 kg·ha−1. Future sacha-inchi improvement programs can select progenies with high TNF and TWF to facilitate the selection of progenies with high TWS.

Agriculture is a fundamental activity for human development. However, its sustainable practice is required to ensure the perpetuity of future resources. In this way, bacteria can benefit crops by making available nutrients and metabolites, mainly contributing to reducing the demand for chemical fertilizers. This study aimed to evaluate the biofertilizing capacity of Azospirillum brasilense, Bacillus megaterium, and Brevibacillus fluminis and their effects on improving the physiological and morphoanatomical properties of strawberry seedlings. In vitro tests were performed to evince their potential to supply nutrients (P and K) and produce siderophores and indole-acetic acid. In an inoculation experiment, these strains were inoculated in isolation and mixed in pairs and triples. This experiment was carried out in a greenhouse in a completely randomized design (CRD). The inoculated treatments were fertilized with 30% N and P demands; the uninoculated control received 30% and 100% of these demands. Leaf gas exchange, total chlorophylls, and crown diameter were evaluated during cultivation. After 138 days, leaf number, nutrient content, root length, root and shoot fresh and dry weight, and total seedlings were evaluated. The bacteria tested positive in all in vitro evaluations except for siderophore production. The strawberry responded positively to inoculation. The inoculation, either in isolation or in a mixture, improved stomatal conductance, leaf transpiration, internal CO2 concentration, leaf N and Mg contents, crown diameter, leaf area, and root elongation. We can conclude that the intermediation of microorganisms improves nutrient use efficiency and reduces the strawberry’s fertilizer demand by up to 70%, leading to plant development and yields comparable to complete fertilization.

This study aimed to investigate the presence of beneficial microorganisms in the micropropagation of Pyrus communis rootstocks through the isolation, identification, and selection of auxin-producing bacteria. The selected microorganisms were also inoculated in vitro to evaluate their effect on the plant rooting process and their behavior during the acclimatization phase. The results showed the presence of endophytic microorganisms in plant tissue cultures of the ‘OH×F87′ and ‘PDW’ selections. A low diversity was observed in the population of microorganisms isolated from the in vitro culture of the ‘OH×F87’and ‘PDW’ selections, with a predominance of the genera Acinetobacter, Bacillus, and Buttiauxella. The selection of promoting microorganisms was performed based on the auxin production test, in which 30.36% of the microorganisms tested positive. In the in vitro inoculation, it was possible to observe the promotion of growth and emission of roots in the pear rootstocks, from the inoculation with bacteria identified as capable of producing auxin. This process can be used to replace the inclusion of synthetic auxin in the productive chain of woody fruit trees propagated by vegetative means, such as pears. None of the bacterial isolates was notably more promising, but the general similarity of treatments containing the A. septicus and A. ursingii strains, with the synthetic auxin treatment, suggests the possibility of its use on a large scale allowing the adoption of the cheaper method. of rooting. This work opens the door for further research using new, more promising microbial isolates, and also for lower-cost microorganism cultivation techniques, such as low-cost media obtained from agro-industrial residues.

Devido a expansão da olivicultura no Brasil e ao elevado número de variedades existentes, estudos visando a caracterização de cultivares são fundamentais. Este trabalho teve por objetivo caracterizar a morfologia interna, quantificar anatomicamente os tecidos foliares e estimar o conteúdo de DNA de seis cultivares de oliveiras do Banco de Germoplasma da Epamig Sul de Minas. Para o estudo anatômico folhas totalmente expandidas de oliveiras foram cortadas em secções transversais e avaliadas em relação a espessura da epiderme da face adaxial e abaxial, espessura do parênquima paliçádico e lacunoso, espessura do mesofilo e nervura central. Foram registradas 128 fotomicrografias, sendo 64 do limbo foliar e 64 da nervura central, divididas em 4 repetições. Para a determinação do conteúdo de DNA, aproximadamente 70 mg de tecido foliar juntamente com Glycine Max (padrão de referência interno) foram triturados em placa de Petri contendo 1 mL de tampão Marie. A suspensão de núcleos foi filtrada através de malha de 50 μm, sendo corados com adição de 15 μL com iodeto de propídeo para cada amostra. Para cada tratamento, três amostras de 10 mil núcleos foram analisadas em citômetro Facscalibur (Becton Dickinson). O conteúdo de DNA das cultivares de oliveiras variaram de 2,54 a 2,89 pg. A estrutura básica das cultivares de oliveiras é a mesma, porém, há distinção nas espessuras dos tecidos foliares, na nervura central e no mesofilo.

One of the factors that can compromise the strawberry culture is the use of seedlings without phytosanitary quality. The aim of this study was to evaluate the use of three biological products in the production of strawberry cultivars. For this, six cultivars ('Camino Real', 'Festival', 'Oso Grande', 'Albion', 'San Andreas' and 'Camarosa') were selected to receive the following treatments: T1) Onix (2.4 mL) + Qualit (0.6 mL) (Bacillus methylotrophicus + Trichoderma asperellum); T2) Rhizos (2.4 mL) + Qualit (0.6 mL) (Bacillus subtilis + Trichoderma asperellum) and T3) Control. After the production cycle, the total production (g kg-1), estimated average production (kg ha-1) and number of fruits in each plot were evaluated. 'Festival' and 'Oso Grande' were the most productive cultivars and their greatest yields were observed in the presence of Bacillus compared to control. Plants grown in the presence of B. methylotrophicus and B. subtilis showed a higher number of fruits. The use of these biological products is important for strawberry cultivation.

Rose essential oil is rich in compounds widely used by the pharmaceutical and cosmetic industry, due to the biological activities it presents. However, obtaining oil is costly, as the yield per plant is low, which requires several techniques that aim to increase its production. The application of growth-promoting bacteria has been studied for this purpose. Thus, the objective of this work was to select efficient bacteria for production and evaluate their influence on the phytotechnical characteristics and composition of the essential oils of roses. Seven species of bacteria were evaluated for the potential to promote growth in vitro, being tested for nitrogen fixation, phosphate solubilization, protease production and auxin production. From bacteria tested, four were selected and inoculated on rose plants of cultivar Black Prince to evaluate the influence on phytotechnical variables of flower and stem and the oil production. The evaluation of the production of roses was performed through the characteristics of the flowers (size, weight, and diameter of the stem) and floral bud. The essential oils from the inoculated flowers were extracted and evaluated in terms of content, yield, and chemical composition. The application of B. acidiceler, B. subtilis and B. pumilus resulted in flowers with a diameter up to 29% larger. The floral stem was increased by up to 24.5% when B. acidiceler and B. pumilus were used. Meanwhile, the stem diameter was around 41% greater in the presence of B. acidiceler, B. subtilis and in the control. Bacillus pumilus also increased the weight of fresh petals (104%) and essential oil yield (26%), changing the chemical composition of the extracted essential oil. Thus, it is concluded that B. acidiceler, B. pumilus, and B. subtilis improved the phytotechnical characteristics of roses. Among bacteria, B. pumilus increased the essential oil content as well as positively changed the chemical composition of the extracted essential oil.

Although the demand for organic fertilizers in agriculture is growing, it remains incipient in some production sectors, such as medicinal plant production, which does not possess specific technology for its development. Solid residues are highly contaminant to water sources, soil, populations and biodiversity but can potentially be used to produce organic composts and vermicompost, such production not only enables nutrient recycling but also acts on soil conditioning, increasing soil organic matter and improving its physical, chemical and biological characteristics, as well as strengthening organic production with an emphasis on medicinal plant production. In this context, recommendations for and applications of organic fertilizers available in the market were reviewed; in addition, the imminent socioeconomic demand for organic compost and vermicompost production was contextualized based on residues from coffee and sugarcane production and cattle farming for application to the medicinal plant production chain. It is concluded that although these sectors produce a considerable amount of residues, they are not being reused in formulation of organic composts and vermicompost, and commercial organic fertilizers recommended for medicinal plant production were not found. Thus, the formulation of vermicomposting and composting from the reuse of agricultural residues, are potential social, economic technologies and tools to be valued and disseminated to traditional and family farmers.

In vitro culture systems based on liquid culture media are considered to be more effective than semisolid culture medium systems. Liquid culture media systems provide better nutrient availability for plant tissues, easier culture handling, and the potential for scaling up and automation. However, in vitro liquid culture requires more careful handling due to the potential for contamination and the possibility of negative effects, such as hyperhydricity or vitrification, that hinder the growth and development of the plant material. Temporary immersion bioreactors have emerged as a workable alternative for capturing the benefits of liquid media, though semisolid systems are still traditional. Many studies have shown that silicon (Si) is a beneficial plant nutrient. Silicon might have a positive effect in both semisolid and liquid in vitro systems. The objective of this study was to evaluate the effect of silicon on the micropropagation and acclimatization of banana plants cultivated in vitro by comparing liquid temporary immersion bioreactor technology and semisolid traditional culture systems. Different silicon concentrations (0 and 1 mL L-1) and culture systems (liquid temporary immersion bioreactor and semisolid traditional culture) were evaluated over a 36-day period. The growth characteristics plant size, fresh and dry weight, and number and length of leaves and roots were evaluated. After the 36-day in vitro growth period, plants were transferred to a greenhouse for acclimatization and were evaluated after 30 days for the same growth characteristics used in the in vitro studies. The temporary immersion bioreactor system resulted in greater growth of banana plants compared to the traditional semisolid system. Temporary immersion bioreactors also showed a positive interaction with Si and resulted in higher values for all growth characteristics in the acclimatization phase.

Morphological and agronomical describers are traditionally used in plant characterization. However, the usage of these describers have some limitations such as susceptibility to abiotic and biotic stress and environmental factors. Furthermore, the describers are not stable over time and many can only be evaluated during the adult phase of the plants, which requires time and physical space. Molecular markers offer numerous advantages compared to the conventional alternatives based on phenotype: they are stable and detectable in all vegetable tissues, and are independent of the environment and development phase. One of the main advantages of the use of molecular markers is the time reduction in the identification of genetic diversity among the studied subjects, as the genotypes may even be described for the seed or seedling phase. Many countries have already adopted molecular markers to identify olive cultivars more accurately. The aim of this study was to evaluate the genetic identity of eight olive accessions supposedly belonging to cultivar Arbequina by using microsatellite (SSR) and Sequence Characterized Amplified Region (SCAR) markers. One accession corresponding to the cultivar was also incorporated into the analysis as a reference genotype. The molecular marker data were analyzed on the software GENALEX6. The markers generated an accumulated PI and PE of 1.26 x 10-6 and 0.949, respectively. The results supported the hypothesis that all accessions belong to the cultivar Arbequina, and the markers can therefore be applied to other varieties of olive species.

The biotechnological interest in genus Physalis has increased in the last decades, however, there are still few micropropagation studies of this genus. The objective of this study was to evaluate P. angulata photoautotrophic and photomixotrophic micropropagation with gas exchange under seven light spectra and five concentrations of sucrose. Lighting were yellow, blue, white, red, green, red + blue LEDs and natural light filtered by mesh. Sucrose concentrations were 0, 7.5, 15, 22.5 and 30 g.L-1. Phytotechnical, anatomical features and photopigment contents were evaluated through stem and root segment length, leaf number, leaf area, chlorophyll a and b contents, carotenoids, adaxial epidermis, palisadic and spongy parenchyma and abaxial epidermis. The data were compared by Scott-Knott's mean test and principal components analysis using the R software. Comparing the variables within lighting types, it was observed that only the screen treatment, screen-filtered natural illumination, obtained assessment in all variables. Comparing the levels of sucrose, it was observed that the treatment 15 g.L-1 sucrose obtained the highest number of averages with maximum evaluation. It was concluded that the natural light filtered by screen with 50% of shading allowed the photoautotrophic micropropagation of P. angulata. Better development results were observed in photomixotrophic micropropagation with 15 g.L-1 of sucrose.

Physalis alkekengi is an ornamental plant that can also be used as a medicinal plant due to its anti-inflammatory, bactericidal, antitumor and fungicidal properties. Polyploidization can be an important tool in the genetic improvement of this species. The objective this work was to obtain tetraploids in vitro and to evaluate the phytotechnical traits of P. alkekengi. For this, nodal segments of P. alkekengi var. Franchettii were inoculated into petri dishes containing 100 ml of MS medium supplemented with colchicine at concentrations 0; 0.04; 0.08; 0.12; and 0.16% and kept in the dark for 24 and 48h. After the respective treatment periods with colchicine the segments were inoculated into test tubes. The tetraploids were identified by flow cytometry and classical cytogenetics. In vitro seedlings were measured: root length, nodal segment length, leaflet number and total leaf area. In the acclimatization phase, the area of ​​the second leaf and total leaf, petiole radius, stem length, fruit weight with calyx, without calyx, fruit diameter, number of seeds and brix of the pulp were evaluated. Chlorophyll a, chlorophyll b, total chlorophyll, total carotenoid, total chlorophyll / total carotenoid ratio and chlorophyll a / b ratio were also estimated. The treatment that most produced tetraploid seedlings was with 0.08% colchicine per 24h. No significant difference was observed in 7 (seven) variables, these being all variables of photopigments, stem diameter (steam) and brix. In general, diploid (2x) plants were better in 9 (nine) while tetraploid seedlings were better in 6 (six) of the phytotechnical variables. It was concluded that the MS medium supplemented with 0.08% colchicine for 24 h allowed P. alkekengi tetraploides to be obtained with better phytotechnical qualities.

Abstract: The objective of this work was to evaluate the effects of temperature and osmotic agents on the in vitro conservation of Cape gooseberry (Physalis peruviana). Temperatures at 18 and 25°C, as well as the osmotic agents sucrose, mannitol, and sorbitol were tested. A short-term in vitro conservation of Cape gooseberry can be achieved at 18°C, using 30 g L-1 sucrose.

Abstract: The objective of this work was to evaluate the effect of silicon fertilization on gas exchange, leaf anatomy, and ultrastructural characteristics of passion fruit (Passiflora edulis). The treatments comprised four concentrations of silicon (0, 0.28, 0.55, and 0.83 g per pot) at 1% silicic acid solution (SiO2.XH2O). This solution was applied around the stems of the plants. The first application was made 15 days after seedlings were transplanted. In total, three applications were made at 15-day intervals. The pots that constituted the control treatment received water in the same amount. After the final application, the plants were subjected to analyses of gas exchange, anatomical changes, and ultrastructural characteristics. The use of silicon promotes anatomical changes in passion fruit seedlings, such as increased adaxial epidermis thickness, reduced palisade parenchyma, and increased polar diameter/equatorial diameter ratio, which is related to stomata functionality. The concentrations of 0.55 and 0.83 g silicon per pot provide higher rates of photosynthesis, of transpiration, and stomatal conductance. The concentration of 0.83 g silicon per pot results in the greatest deposition of silicon in the abaxial epidermis of leaf surface.

Abstract: The objective of this work was to evaluate the effect of silicon and agar concentrations on cockscomb (Celosia cristata) (Amaranthaceae) development in vitro. Phytotechnical, anatomical, and ultrastructural analyses were carried out in a completely randomized design, in a 4x3 factorial arrangment, with four silicic acid concentrations (0.0, 0.5, 1.0, and 1.5 g L-1) and three agar concentrations (5.5, 8.0, and 10.5 g L-1), totaling 12 treatments with seven replicates. Celosia cristata explants were inoculated in vitro in a Murashige & Skoog (MS) culture medium, with 30 g L-1 sucrose. The analyses were conducted 30 days after inoculation. Phytotechnical traits improve with agar concentration of 8.0 g L-1, and the association of this concentration with 1.0 g L-1 silicon also contributes to the improvement of anatomical attributes, especially of leaf blade width and thickness of the palisade and spongy parenchyma, which contributes to the development of C. cristata. None of the evaluated combinations of agar and silicon contributes to Si deposition on the foliar epidermis of this ornamental species.

Abstract: The objective of this work was to evaluate the effects of the solidifying agents agar and phytagel and of activated charcoal on the in vitro cultivation of two maná cubiu (Solanum sessiliflorum) varieties: Thaís and Santa Luzia. The phytotechnical characteristics analyzed included number of leaves, number of roots, shoot and root length, and fresh matter of shoot and root. Regardless of the variety, phytagel was superior to agar as a culture medium. A greater number of leaves and longer shoots were observed in the Santa Luzia variety, in the absence of charcoal. The Thaís variety showed longer shoots and roots in the presence of charcoal.

Garlic is a health promoter that has important bioactive compounds. The bioactive extraction is an important step in the analysis of constituents present in plant preparations. The purpose of this study is to optimize the extraction with the best proportion of solvents to obtain total phenolic compounds (TPC) and thiosulfinates (TS) from dried garlic powder, and evaluate the antioxidant activities of the optimized extracts. A statistical mixture simplex axial design was used to evaluate the effect of solvents (water, ethanol, and acetone), as well as mixtures of these solvents, after two ultrasound extraction cycles of 15 min. Results showed that solvent mixtures with a high portion of water and pure water were efficient for TPC and TS recovery through this extraction procedure. According to the regression model computed, the most significant solvent mixtures to obtain high TPC and TS recovery from dried garlic powder are, respectively, the binary mixture with 75% water and 25% acetone and pure water. These optimized extracts presented oxygen radical absorbance capacity. Pure water was better for total antioxidant capacity, and the binary mixture of water–acetone (75:25) was better for DPPH scavenging activity. These optimized extracts can be used for industrial and research applications.

The objective was to evaluate morphological and physiological differences in anthurium plants in vitro, with the use of silicon added to the culture medium. Nodal segments were inoculated in Pierik with different sodium silicate concentrations (0.0, 0.5, 1.0 or 2.0 mg L-1). After 100 days in a growth room, phytotechnical characteristics were evaluated, physiological concentrations of silicon, photosynthetic pigments and microanalysis X-ray. A higher yield of chlorophyll a and b, was observed in plants supplemented with 2.0 mg L-1 of sodium silicate. Anthurium plants showed better growth development with an increase in the number of leaves, dry weight and length of the aereal part in plants supplemented with 0.5 and 2.0 mg L-1 sodium silicate. It was also observed an increase in the number of roots of plants supplemented with 1.0 mg L-1 of sodium silicate. The use of sodium silicate in culture medium improves the quality of plantlets with an increased absorption of nutrients in the plant Anthurium.

O objetivo do presente trabalho foi avaliar o crescimento de bananeiras micropropagadas cv. BRS FHIA-18 em condições de casa de vegetação com uso de Basacote® e substratos. Para a instalação do experimento, foram utilizadas bananeiras micropropagadas cv. BRS FHIA-18. Os tratamentos foram constituídos de concentrações de Basacote® (0; 3; 6 e 9 kg m-3 de substrato) e substratos: Plantmax® HT, Plantmax® HT + casca de arroz carbonizada (CAC) e terra de subsolo + CAC. Após 90 dias do transplantio, foram avaliados altura de planta (cm), comprimento do sistema radicular (cm), número de raízes e relação entre massa seca (g) da parte aérea e raízes. O substrato Plantmax® HT acrescido de 3 kg m-3 de Basacote® é o mais indicado visando o melhor crescimento de bananeiras cv. BRS FHIA-18 na fase de aclimatização.

The barueiro (Dipteryx alata Vog.) is a native fruit species of the Cerrado ecoregion that has multiple uses. It is a wild species, and its cultivation is difficult. Furthermore, it is threatened with extinction. Plant tissue culture is a major tool for the conservation of germplasm, as well as a means of propagating high-quality seedlings on a large scale. However, this technique has not been used with barueiro, although it might provide valuable contributions to the process of barueiro domestication. The most popular method of cultivation is the use of the Murashige and Skoog medium (MS), which is considered one of the most nutritionally complete media. Woody plant medium (WPM) is indicated for the propagation of woody species, but there are no reports of its use for barueiro cultivation. Woody plants tend to have problems with rust in vitro during the establishment phase. Activated charcoal acts as an adjuvant for the adsorption of phenolic compounds, mitigating its effects in the medium. Thus, the objective of this study was to test four activated charcoal doses (0, 2, 4 and 6 g L-1) and three culture media: MS, WPM, and AA (over water agar) in the in vitro establishment of barueiro. The experimental design was a completely randomised (DIC), 4 × 3 factorial design with three replications. At 60 days after inoculation, the explants were evaluated for dry matter, fresh weight, stem diameter, shoot length, number of leaves, longest root length, germination rate, and chlorophyll contents. The MS medium supplemented with 3,0 g L-1 activated charcoal appeared to be the best for in vitro establishment of barueiro.

The study aims to compare the efficiency of previously used liquid media for coffee, evaluating NAA concentrations in liquid medium and proline in semi-solid medium in the regeneration of somatic embryos and asses concentrations of BA and IAA in the maturation of embryos in temporary immersion bioreactors. For the regeneration of globular embryos from embryogenic aggregates and calli, we tested five concentrations (0.00, 0.25, 0.50, 1.00 and 2.00 mg L-1) of NAA in liquid medium and five concentrations (0.0, 0.5, 1.0, 2.0 and 4.0 g L-1) of proline in semisolid medium. The multiplication of embryogenic aggregates was highest in culture medium MM, reaching a density 7.5 times greater than that of the initial density. NAA promoted a linear increase in embryo regeneration. The medium containing 2.0 mg L-1 BA and 0.0 mg L-1 IAA yielded the highest percentage of large cotyledonary embryos

ABSTRACT Genipapo is a species with an intermediate seed storage behavior, and its germination is slow and asynchronous; therefore the tissue culture is an alternative strategy for the propagation in large-scale. This study aimed to evaluate three genipapo accessions at different micropropagation stages (adventitious shoot induction, in vitro rooting and acclimatization). Genipapo nodal segments from the Sabinópolis (AS), Cruz das Almas (CZA) and Núcleo Bandeirante (NB) accessions were used and inoculated in culture media with 0 and 1.0 mg L-1 6-benzylaminopurine (BAP). Different indole-3-butyric acid (IBA) concentrations were tested for in vitro rooting. Subsequently, the effect of two substrates on the seedling development of three genipapo accessions was assessed. The molecular characterization of accessions was performed using 15 inter-simple sequence repeat (ISSR) primers, and genotype clustering was performed based on genetic dissimilarity using the Unweighted Pair-Group Method with Arithmetic Mean (UPGMA). Culture media supplementation with 1.0 mg L-1 BAP favors the development of adventitious shoots and promotes a higher callogenesis percentage, leaf number and feasibility at 90 days of in vitro culture. The immersion of the basal portion of shoots for 20 seconds in all IBA solutions induces the rhizogenesis in the genipapo accessions at 90 days of in vitro culture. The substrates consisting of washed sand + dried coconut shell powder, at a 1:1 ratio by volume, and Topstrato HT(r) may be recommended for genipapo acclimatization. The NB accession is genetically different from the CZA and AS populations and shows superiority for most of the variables analyzed.

RESUMO A determinação do nível de ploidia é muito importante, principalmente em programas de melhoramento genético que envolvem poliploides, a fim de possibilitar a escolha adequada dos materiais vegetais com os quais se deseja trabalhar. A relação entre o conteúdo de DNA de acessos de bananeira e sua ploidia ainda permanece controversa na literatura; assim, o presente trabalho teve como objetivo avaliar o conteúdo de DNA de acessos de bananeira com diferentes níveis de ploidia. Foram avaliados sete acessos tetraploides, quatro triploides e quatro diploides. A determinação do conteúdo foi realizada pela técnica de citometria de fluxo. Foram trituradas entre 50-60 mg de folhas frescas, juntamente com o padrão interno (Pisum sativum) no tampão LB01, e, posteriormente, as amostras foram filtradas em gaze e filtro de 50 µm. Adicionaram-se 5 µL de RNase e 25 µL de iodeto de propídeo. Para cada amostra, foram analisados 10 mil núcleos, com três repetições. Os resultados obtidos para o conteúdo de DNA permitiram estimar o tamanho dos genomas A e B, sendo o primeiro cerca de 14% maior que o segundo. Os resultados apresentaram clara relação entre o conteúdo de DNA e o nível de ploidia dos materiais. O contéudo de DNA apresentou aumento médio de 30% nas cultivares diploides em relação às cultivares triploides avaliadas e de 25% nas cultivares triploides em relação às cultivares tetraploides. Apesar da diferença nos tamanhos dos genomas A e B, contribuições distintas desses dois genomas não foram diretamente relacionadas com alterações no conteúdo do DNA de cultivares tetraploides.

Abstract The use of silicon in Billbergia zebrina cultivation in vitro is an alternative for optimizing micropropagation of this important ornamental plant species. The objective of the present study was to evaluate the growth and anatomical and physiological alterations in Billbergia zebrina (Herbert) Lindley plants as a function of different sources and concentrations of silicon during in vitro cultivation and acclimatization. The experimental design was completely randomized, with a double factorial arrangement and an additional control treatment (2 x 3 + 1). The first factor was relative to calcium silicate and sodium silicate added to the Murashige & Skoog culture medium; the second factor was related to its concentrations, 0.5, 1.0, and 2.0 mg L-1. After 100 days, their growth, anatomical characteristics, level of silicon and chlorophyll content were evaluated. Growth characteristics were assessed after 60 days of acclimatization period. Plants absorbed more sodium silicate than calcium silicate. This source also stressed the plants impairing their growth, but the highest silicon absorption at 1 mg L-1 attenuated the stressful conditions. The supplementation of the culture medium with calcium silicate led to improved growth, anatomical, and physiological characteristics, which benefited the development of more resistant seedlings with better performance during acclimatization.

Abstract The jelly palm plant [Butia capitata (Martius) Beccari] is a native palm of the Cerrado biome used for many purposes in northern Minas Gerais State, Brazil. Dormancy is common in palm seeds, resulting in slow and uneven germination that may take years to complete. Modification in the growth pattern, anatomical parameters, physiological and biochemical characteristics of the plant can be verified due to changes in the light spectrum transmitted through colored shade nets used. Therefore, the objective of this study is to evaluate the effect of colored shade nets on the leaf and root anatomy of the jelly palm plant. The experiment was performed in a completely randomized design, with five treatments, ten replicates and eight plants per replicate, totaling 400 plants. Four colored photo-converter nets with 50% shading and different radiation proportions were employed: white (985 μmol.m-2.s-1), red (327 μmol.m-2.s-1), black (433 μmol.m-2.s-1) and silver (405 μmol.m-2.s-1). The plants cultivated under direct sunlight (1000 μmol.m-2.s-1) were considered as the control group. Leaf and root anatomical analysis was performed on 10 plants per treatment. It is possible to conclude that the colored shade nets caused changes in leaf and root anatomy of the jelly palm plant (Butia capitata).

Banana cultivation is an agricultural activity practiced in different regions and constantly subjected to abiotic stresses that limit its productivity. To treat the effect of these stresses research can be undertake by simulating them in vitro since it limit the effect of the external factor in the experiment. Therefore, the objective of this study was to simulate the compaction in banana plant cultivated in vitro using Phytagel. To realize the experiment, we used MS culture medium with two distinct consistency added in the testing tubes. In the bottom part was added 10 mL of culture medium with consistency of jellification: 1.8, 2.8, 3.8, 4.8 and 5.8 g L-1 of Phytagel. Over this culture medium was added 5mL of half MS with consistency standard 1.8 g L-1 of Phytagel. Posteriorly, the planting materials from cultivar Grand Naine, BRS Vitória and BRS Princesa were inoculated in the growth medium. After 30 days of culture the plant materials were submitted for agronomic and physiological evaluation. The result showed non-significant difference among the compaction factors on physiological parameters however variety Grand Naine presents better performance in this character. Besides variety Grand Naine increased the rate of photosynthesis under compaction. This behaviour probably occurred due to overcoming the effect of stress by the variety. Therefore, it can be concluded that the cultivar Grand Naine is superior to cultivars BRS Vitória and BRS Princesa since it produces superior performance on rate of photosynthesis, stomatal conductance, and transpiration under simulated compaction conditions that favor the accumulation of plant biomass.

Butia capitata (Mart.) Becc., commonly known as jelly palm, is a palm tree native to the Cerrado biome. It is considered an endangered species owing to intensive extractive exploitation of its fruits, with slow and uneven seminiferous propagation as an aggravating factor. Thereby, there are some bottlenecks related to jelly palm seedling production that needs to be optimized. Light quality and intensity is very important to seedling production, as it controls the metabolism of plants and consequently their growth and development. Thus, the aim of this work is to evaluate the effect of shade nets on the growth and physiological aspects of jelly palm seedlings. The experimental design was completely randomized, with five treatments, ten replicates and eight plants per replicate, totaling 400 plants. Experimental treatments consisted of the use of shade nets with 50% shading and different radiation intensity: white (985 µmol m-2 s-1), red (327 µmol m-2 s-1), black (433 µmol m-2 s-1), and silver (405 µmol m-2 s-1). Full sun (1000 µmol m-2 s-1) was used as the control treatment. Growth and physiological analyses of the plants were performed after six months of treatment. We concluded that the red shade net increases growth and biomass of Butia capitata plants. However, the use of shade nets had no effect on the tested physiological characteristics of this species. The red shade net is the most suitable for the production of Butia capitata seedlings in the southern region conditions of Minas Gerais State.

Uvaia (Eugenia pyriformis) is a fruit tree of the Myrtaceae family. It has recalcitrant seeds of limited longevity, making seed propagation difficult. Micropropagation is an alternative method to obtain a large quantity of progeny plants in a short period of time, by using any part of the plant as explant. The high concentration of phenols associated with the chemical composition of the Myrtaceae, and the presence of microorganisms in the plant material or culture media, can make in vitro propagation difficult and/or impossible. The objective was to evaluate various concentrations of antioxidants affecting the control of microbial contamination and phenol oxidation in vitro in uvaia. A completely randomized design was used, with a 3 (antioxidants PVP, l-cysteine, and ascorbic acid) × 3 (antioxidant concentrations 100, 200, and 300 mg L-1) × 2 (activated charcoal at 0 and 2 g L-1) factorial arrangement + 2 additional variables (absence of antioxidants and activated charcoal; absence of antioxidants with 2 g L-1 activated charcoal), with three repetitions comprising four plants each. The percentage of bacterial and fungal contaminations, along with the number of oxidized explants, was evaluated after 7, 14 and 21 days of in vitro cultivation. It was concluded that, where bacterial and fungal contaminations were concerned, in vitro cultivation of uvaia can be performed without the use of antioxidants. PVP or ascorbic acid must, however be used in the process, at a concentration of 300 mg L-1, along with 2 g L-1 of activated charcoal. This helps to minimize phenol oxidation.

O cultivo de amoras está amplamente difundido em zonas temperadas, porém, algumas cultivares são de baixa necessidade em frio e podem ser exploradas em locais com temperaturas mais elevadas. Assim, objetivou-se, com o presente trabalho, avaliar a produção de amoras-pretas e amora-vermelha na região de Lavras-MG (clima Cwb). O delineamento experimental foi em blocos ao acaso, com quatro blocos e onze tratamentos (cultivares de amoreiras-pretas 'Arapaho', 'Xavante', 'Ébano', 'Comanche', 'Caingangue', 'Choctaw', 'Tupy', 'Guarani', 'Brazos', 'Cherokee' e a amoreira-vermelha, espécie nativa do Brasil). Em cada parcela, foram coletados dados fenológicos e produtivos no ciclo de produção 2010/11 e 2011/12, além da caracterização físico-química dos frutos. As cultivares de amoreira-preta apresentaram ciclo produtivo entre 66 e 133 dias, com colheitas se iniciando em setembro e se estendendo até janeiro; e a amoreira-vermelha com ciclo produtivo de 283 dias. 'Brazos' apresentou a maior produtividade estimada. As cultivares Brazos e Guarani possibilitaram a produção de frutos de maior massa, enquanto que 'Caingangue', 'Tupy' e 'Choctaw' apresentaram bom equilíbrio entre os sólidos solúveis e acidez. A amoreira-vermelha apresentou elevada produção de frutos (527g por planta no 1o ciclo e 344g por planta no 2o ciclo) e demonstrou-se uma excelente opção para o processamento

This study aimed to induce callus formation in Jatropha curcas L. and to evaluate the ultrastructure and cytochemical behavior of the calli. Calluses were induced with 2,4-D, picloram-PIC, kinetin (Kin) and BAP: (1) control; (2) 4.52 µM 2,4-D; (3) 9.04 µM 2,4-D; (4) 4.14 µM PIC; (5) 8.28 µM PIC; (6) 4.52 µM 2,4-D + 2.32 µM KIN; (7) 9.04 µM 2,4-D + 4.64 µM KIN; (8) 4.14 µM PIC + 2.32 µM KIN; (9) 8.28 µM PIC + 4.64 µM KIN; (10) 4.52 µM 2,4-D + 2.22 µM BAP; (11) 9.04 µM 2,4-D + 4.44 µM BAP; (12) 4.14 µM PIC + 2.22 µM BAP and (13) 8.28 µM PIC + 4.44 µM BAP. It was evaluated the percent coverage of the explants by callus (% CEC) and performed scanning electron microscopy (SEM) and acetocarmine/Evans blue double staining to analyze the embryogenic potential of the calli. As shown by scanning electron microscopy and acetocarmine/Evans blue staining, we found that J. curcas callus formation was optimal with 4.52 µM of 2,4-D.

Este trabalho teve como objetivo avaliar o efeito da alteração da qualidade espectral da luz, utilizando malhas de transmissão de luz diferenciada, sobre características da anatomia foliar em plantas de tamarindo (Tamarindus indica L.), visando à obtenção de plantas mais propícias ao plantio. Mudas de tamarindo foram cultivadas sob malhas de 50% de sombreamento nas cores branca, azul, vermelha e preta em delineamento inteiramente casualizado. Após 90 dias de cultivo sob as malhas, as folhas foram avaliadas quanto à anatomia e micromorfologia. Plantas submetidas ao cultivo sob malha branca apresentaram maior altura das células da epiderme na face abaxial e maior espessura do parênquima paliçádico e da nervura central. Melhores resultados para epiderme na face adaxial e limbo foliar foram observados sob malhas branca e azul. Maiores densidades estomáticas foram obtidas sob malhas azul e vermelha. As folhas de Tamarindus indica apresentam plasticidade anatômica em resposta às modificações no espectro da radiação. Em face desses resultados, as malhas branca e azul podem ser recomendadas para obtenção de plantas mais propícias ao plantio.

Artificial chromosome duplication of diploid genotypes of Lolium multiflorum (2n=2x=14) is worthy to breeding, and aims to increase the expression of traits with agronomic interest. The purpose of this study was to obtain polyploid plants of L. multiflorum from local diploid populations in order to exploit adaptation and future verification of the effects of polyploidy in agronomic traits. Seedlings were immersed in different colchicine solutions for an exposure time of 3h and 24h. Ploidy determination was made by the DNA content and certified by chromosomes counts. The plants confirmed as tetraploids were placed in a greenhouse, and, at flowering, pollen viability was evaluated, and seeds were harvested to assess the stability of the progenies. The percentage of polyploids obtained was 20%. Pollen viability of the tetraploids generated ranged from 58% to 69%. The tetraploid plants obtained in the experiment generated 164 progenies, of which 109 presented DNA content compatible with the tetraploid level, showing stability of chromosome duplication in the filial generation.

Research suggests that the development of micropropagated banana plants can be improved by altering nutrient concentrations in the culture medium. The aim of this study was to evaluate the in vitro development of banana plants exposed to varying concentrations of calcium and magnesium sulfate. The shoot tips of banana cv. Prata-Anã were inoculated in flasks (volume, 250 cm3) containing 50 mL of MS culture medium. The culture medium contained varying concentrations of CaCl2 (0, 220, 440, 880 mg L-1) and MgSO4 (0, 185, 370, 740 mg L-1. A completely randomized experimental design was employed, based on a 4 × 4 factorial scheme (four levels of CaCl2 concentration, and four of MgSO4). The MS culture medium containing 880 mg L-1 of CaCl2 but no MgSO4 showed the highest increment in the number of leaves (6.0). The highest number of roots was observed in the absence of CaCl2 and MgSO4 in the medium. Additionally, the shoot length was longer (5.05 cm) when the MS medium was supplemented with 185 mg L-1 of MgSO4. The optimum in vitro development of banana cv. Prata-Anã was obtained when the MS medium was supplemented with 880 mg L-1 of CaCl2 and 370 mg L-1 of MgSO4.

ABSTRACT: Salt stress is one of several major abiotic stresses that affect plant growth and development, and there are many evidences that silicon can ameliorate the injuries caused by high salinity. This study presents the results of an assay concerning: (1) the effect of in vitro NaCl-induced salt stress in cape gooseberry plants and (2) the possible mitigating effect of silicon in saline conditions. For that, nodal segments were inoculated in Murashige and Skoog (MS) medium under salinity (0.5 and 1.0% NaCl) with different silicic acid concentrations (0, 0.5 and 1.0g L-1). Phytotechnical characteristics, photosynthetic pigments content, and leaf anatomy were evaluated after 30 days. Shoot length, root length, number of leaves and buds, fresh and dry weight, pigment content, stomatal density and leaf blade thickness were drastically reduced by increased salt level. The supply of silicon (1.0g L-1) has successfully mitigated the effect of salinity at 0.5% NaCl for chlorophyll, carotenoids, stomatal density and leaf blade thickness. When salt stress was about 1.0%, Si was not effective anymore. In conclusion, we affirmed that, in in vitro conditions, salt stress is harmful for cape gooseberry plants and the addition of silicon showed effective in mitigating the saline effects of some features.