Development of novel robotic platforms for mechanical stress induction, and their effects on plant morphology, elements, and metabolism.

This research evaluates the effect on herbal crops of mechanical stress induced by two specially developed robotic platforms. The changes in plant morphology, metabolite profiles, and element content are evaluated in a series of three empirical experiments, conducted in greenhouse and CNC growing bed conditions, for the case of basil plant growth. Results show significant changes in morphological features, including shortening of overall stem length by up to 40% and inter-node distances by up to 80%, for plants treated with a robotic mechanical stress-induction protocol, compared to control groups. Treated plants showed a significant increase in element absorption, by 20-250% compared to controls, and changes in the metabolite profiles suggested an improvement in plants' nutritional profiles. These results suggest that repetitive, robotic, mechanical stimuli could be potentially beneficial for plants' nutritional and taste properties, and could be performed with no human intervention (and therefore labor cost). The changes in morphological aspects of the plant could potentially replace practices involving chemical treatment of the plants, leading to more sustainable crop production.

De Novo Assembly and Comparative Transcriptome Analyses of Red and Green Morphs of Sweet Basil Grown in Full Sunlight.

Sweet basil (Ocimum basilicum), one of the most popular cultivated herbs worldwide, displays a number of varieties differing in several characteristics, such as the color of the leaves. The development of a reference transcriptome for sweet basil, and the analysis of differentially expressed genes in acyanic and cyanic cultivars exposed to natural sunlight irradiance, has interest from horticultural and biological point of views. There is still great uncertainty about the significance of anthocyanins in photoprotection, and how green and red morphs may perform when exposed to photo-inhibitory light, a condition plants face on daily and seasonal basis. We sequenced the leaf transcriptome of the green-leaved Tigullio (TIG) and the purple-leaved Red Rubin (RR) exposed to full sunlight over a four-week experimental period. We assembled and annotated 111,007 transcripts. A total of 5,468 and 5,969 potential SSRs were identified in TIG and RR, respectively, out of which 66 were polymorphic in silico. Comparative analysis of the two transcriptomes showed 2,372 differentially expressed genes (DEGs) clustered in 222 enriched Gene ontology terms. Green and red basil mostly differed for transcripts abundance of genes involved in secondary metabolism. While the biosynthesis of waxes was up-regulated in red basil, the biosynthesis of flavonols and carotenoids was up-regulated in green basil. Data from our study provides a comprehensive transcriptome survey, gene sequence resources and microsatellites that can be used for further investigations in sweet basil. The analysis of DEGs and their functional classification also offers new insights on the functional role of anthocyanins in photoprotection.

Effects of anesthesia with the essential oil of Ocimum gratissimum L. in parameters of fish stress / Efeitos da anestesia com o óleo essencial de Ocimum gratissimum L. em parâmetros de estresse de peixes

RESUMO: The effects of anesthesia with the essential oil of Ocimum gratissimum (EOO) in parameters of stress after handling were investigated in silver catfish (Rhamdia quelen). EOO was obtained from the aerial parts by hydrodistillation. Juveniles were anesthetized with 70 or 300 mg L-1 EOO and submitted to air exposure for 1 minute. The fishes were sampled immediately or transferred to anesthetic-free aquaria until sampling. In the first experiment, juveniles had their blood collected at 0, 1, 4, and 8 h after handling to assay plasma cortisol and blood glucose levels. The unanesthetized animals were restrained manually for blood collection. In the second experiment, water samples of the recovery aquaria were collected to evaluate net ion fluxes at 0 - 4 h and 4 - 8 h. Water and ethanol controls were also performed under the same conditions. The results showed that the cortisol levels did not differ among the treatments. Hyperglycemia was verified in fish exposed to 70 and 300 mg L-1 EOO at 1 h and 4 h after handling. After 8 h, cortisol and glucose concentrations were lower or similar than those from immediately after handling for all treatments. EOO anesthesia prevented Na+ efflux observed in the control groups in both flux periods. There were net Cl- and K+ effluxes at 0 - 4 h and influxes at 4 - 8 h after handling in most treatments, and these fluxes did not differ among the treatments. The results suggest that EOO did not impair stress recovery and did not act as an additional handling stressor in silver catfish.

RESUMO: Os efeitos da anestesia com o óleo essencial de Ocimum gratissimum (EOO) em parâmetros de estresse após manuseio foram investigados em jundiás (Rhamdia quelen). EOO foi obtido a partir das partes aéreas por hidrodestilação. Os juvenis foram anestesiados com 70 ou 300 mg L-1 de EOO e expostos ao ar por 1 minuto. Os peixes foram amostrados imediatamente ou transferidos para aquários sem anestésico até amostragem. No primeiro experimento, os juvenis tiveram seu sangue coletado em 0, 1, 4, e 8 h após manuseio para avaliar os níveis de cortisol e glicemia. Os animais não anestesiados foram contidos manualmente para coleta sanguínea. No segundo experimento, amostras de água foram coletadas do aquário de recuperação dos animais para avaliação do fluxo iônico entre 0 - 4 h e 4 - 8 h. Grupos controles em água e etanol também foram realizados sobre as mesmas condições. Os resultados demonstraram que os níveis de cortisol não diferiram entre os tratamentos. Hiperglicemia foi detectada em peixes expostos a 70 e 300 mg L-1 de EOO em 1 h e 4 h após o manuseio. Após 8 h, os teores de cortisol e glicose foram menores ou similares aqueles imediatamente após o manuseio para todos os tratamentos. A anestesia com EOO preveniu o efluxo de Na+ observado para os grupos controle em ambos os períodos avaliados. Ocorreram efluxos de Cl- and K+ entre 0 - 4 h e influxos entre 4 - 8 h após o manuseio para a maioria dos tratamentos, e estes eventos não diferiram entre os tratamentos. Os resultados sugerem que o EOO não prejudica a recuperação do animal frente ao evento estressor ou atua como estressor adicional ao manuseio em jundiás.

Linalool and methyl chavicol present basil (Ocimum sp. ) cultivated in Brazil / Linalol e metil-chavicol presentes em manjericão (Ocimum sp. ) cultivados no Brasil

In Brazil, Ocimum species are commonly known as aromatic and restorative herbs. The present research aimed to study the chemical composition of the essential oils of fresh and dry basil (Ocimum sp) leaves obtained by hydrodistillation and analyzed by GC-FID and GC-MS. The obtained yield was 0.70% for dry leaves and 0.26% for fresh leaves. The major compounds were: linalool (29.50-32.26%) and methyl chavicol (36.81-41.62%). Eucalyptol could also be detected (9.99-7.68%). The oil from dry leaves presented a more complex chemical composition. This study serves to contribute to the knowledge of medicinal plants occurring in Brazil.

No Brasil, as espécies de Ocimum são conhecidas como ervas aromáticas e restaurativas. Nesse trabalho foi estudado a composição química dos óleos essenciais das folhas frescas e secas de manjericão (Ocimum sp) obtido por hidrodestilação e analisados por CG-FID e CG-EM. Os teores encontrados foram de 0,70% para as folhas secas e 0,26% para as folhas frescas. Os componentes majoritários foram: Linalol (29,50-32,26%) e metil-chavicol (36,81-41,62%). Eucaliptol também foi detectado (9,99-7,68%). O óleo das folhas secas apresentou composição química mais complexa. Esse trabalho contribui para o conhecimento das plantas medicinais de ocorrência no Brasil.

Produção de mudas de manjericão (Ocimum basilicum L. ) em diferentes substratos e luminosidades / Sweet basil (Ocimum basilicum L. ) seedling production in different substrates and luminosities

Apesar de vários usos na cultura popular, poucos trabalhos vêm sendo desenvolvidos em relação ao cultivo do manjericão, sendo a maior parte dos estudos relacionada à identificação dos compostos químicos e à farmacologia. Este trabalho foi realizado com o objetivo de avaliar o efeito de diferentes luminosidades e substratos na emergência, crescimento inicial e qualidade de mudas de manjericão. Utilizaram-se três substratos (substrato comercial Plantmax®, mistura de terra + areia + cama de frango (1:1:1) e terra + areia + Plantmax® (1:1:1) e dois níveis de luminosidade (Pleno Sol e 50 por cento). O delineamento experimental foi de blocos casualizados em esquema fatorial 2 (Luz) x 3 (Substratos), com quatro repetições. Avaliou-se diariamente o percentual e o índice de velocidade de emergência, e aos 60 dias após a semeadura, o crescimento e a qualidade da muda. Os substratos e níveis de luz não alteraram a porcentagem de emergência das plântulas, entretanto a velocidade de emergência foi maior em Plantmax quando em pleno sol e não diferiu entre os substratos em 50 por cento de sombreamento. No substrato terra + areia + cama-de-frango e a pleno sol as mudas apresentaram maior crescimento e qualidade. Recomenda-se a semeadura direta do manjericão em terra + areia + cama de frango pois evita-se o transplante minimizando as perdas e a necessidade de mão de obra.

Although sweet basil has been frequently used in popular culture, few studies have been developed concerning its cultivation, and most of them are related to the identification of its chemical compounds and pharmacology. The aim of this study was to assess the effect of different luminosities and substrates on the emergence, initial growth and quality of sweet basil seedlings. Three substrates (Plantmax® commercial substrate, a mixture of soil + sand + chicken manure (1:1:1), and soil + sand + Plantmax® (1:1:1) were used, together with two light levels (Full sun and 50 percent). The experimental design was in randomized blocks, in 2 (Light) x 3 (Substrates) factorial arrangement with four replicates. The emergence percentage and velocity index were daily evaluated, and at 60 days after sowing seedling growth and quality were also evaluated. The substrates and light levels did not alter the percentage of seedling emergence; however, the emergence velocity was higher in Plantmax and full sun but did not differ among substrates under 50 percent shading. In the substrate soil + sand + chicken manure and full sun, seedlings had higher growth and quality. It is recommended thus that sweet basil be directly sown in soil + sand + chicken manure since it prevents transplanting, minimizing losses and the need of labor.

Hairy root cultures for secondary metabolites production.

Hairy roots (HRs) are differentiated cultures of transformed roots generated by the infection of wounded higher plants with Agrobacterium rhizogenes. This pathogen causes the HR disease leading to the neoplastic growth of roots that are characterized by high growth rate in hormone free media and genetic stability. HRs produce the same phytochemicals pattern of the corresponding wild type organ. High stability and productivity features allow the exploitation of HRs as valuable biotechnological tool for the production of plant secondary metabolites. In addition, several elicitation methods can be used to further enhance their accumulation in both small and large scale production. However, in the latter case, cultivation in bioreactors should be still optimized. HRs can be also utilised as biological farm for the production of recombinant proteins, hence holding additional potential for industrial use. HR technology has been strongly improved by increased knowledge of molecular mechanisms underlying their development. The present review summarizes updated aspects of the hairy root induction, genetics and metabolite production.

Plant cell cultures: bioreactors for industrial production.

The recent biotechnology boom has triggered increased interest in plant cell cultures, since a number of firms and academic institutions investigated intensively to rise the production of very promising bioactive compounds. In alternative to wild collection or plant cultivation, the production of useful and valuable secondary metabolites in large bioreactors is an attractive proposal; it should contribute significantly to future attempts to preserve global biodiversity and alleviate associated ecological problems. The advantages of such processes include the controlled production according to demand and a reduced man work requirement. Plant cells have been grown in different shape bioreactors, however, there are a variety of problems to be solved before this technology can be adopted on a wide scale for the production of useful plant secondary metabolites. There are different factors affecting the culture growth and secondary metabolite production in bioreactors: the gaseous atmosphere, oxygen supply and CO2 exchange, pH, minerals, carbohydrates, growth regulators, the liquid medium rheology and cell density. Moreover agitation systems and sterilization conditions may negatively influence the whole process. Many types ofbioreactors have been successfully used for cultivating transformed root cultures, depending on both different aeration system and nutrient supply. Several examples of medicinal and aromatic plant cultures were here summarized for the scale up cultivation in bioreactors.

Guard cell apoplastic photosynthate accumulation corresponds to a phloem-loading mechanism.

Apoplastic phloem loaders have an apoplastic step in the movement of the translocated sugar, prototypically sucrose, from the mesophyll to the companion cell-sieve tube element complex. In these plants, leaf apoplastic sucrose becomes concentrated in the guard cell wall to nominally 150 mM by transpiration during the photoperiod. This concentration of external sucrose is sufficient to diminish stomatal aperture size in an isolated system and to regulate expression of certain genes. In contrast to apoplastic phloem loaders and at the other extreme, strict symplastic phloem loaders lack an apoplastic step in phloem loading and mostly transport raffinose family oligosaccharides (RFOs), which are at low concentrations in the leaf apoplast. Here, the effects of the phloem-loading mechanism and associated phenomena on the immediate environment of guard cells are reported. As a first step, carbohydrate analyses of phloem exudates confirmed basil (Ocimum basilicum L. cv. Minimum) as a symplastic phloem-loading species. Then, aspects of stomatal physiology of basil were characterized to establish this plant as a symplastic phloem-loading model species for guard cell research. [(14)C]Mannitol fed via the cut petiole accumulated around guard cells, indicating a continuous leaf apoplast. The (RFO+sucrose+hexoses) concentrations in the leaf apoplast were low, <0.3 mM. Neither RFOs (<10 mM), sucrose, nor hexoses (all, P >0.2) were detectable in the guard cell wall. Thus, differences in phloem-loading mechanisms predict differences in the in planta regulatory environment of guard cells.