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Quinoa is a model halophyte plant, with seeds rich in proteins, fatty acids and lacking prolamines. There are two types of quinoa cultivars: highland and coastal. Coastal cultivars are used in breeding programs for warm-season quinoa production. Different biotechnological tools are useful for breeding and understanding the mechanisms involved in abiotic stress tolerance. However, micropropagation protocols have been developed only for highland cultivars. The aim of this research was to develop a micropropagation protocol for coastal cultivars. The initial explants were apical segments from two coastal cultivars (Cahuil and Villa). The regeneration rate in regeneration quinoa media 3 (QM-3: MS supplemented with 1 mg l−1 KIN and 1 mg l−1 BA) was acceptable (93 ± 5% for Cahuil and 79 ± 8% for Villa), but the number of regenerated shoots was low (2.14 ± 0.93 and 1.43 ± 0.73 respectively). We included a shoot multiplication stage using regeneration quinoa medium 1 (QM-1: MS supplemented with 2 mg l−1 BA), obtaining 7.96 ± 2.92 shoots per explant for Cahuil and 4.10 ± 3.00 for Villa. Also, we obtained a higher number of acclimatized quinoa using ex vitro shoot rooting (73 ± 8% for Cahuil and 77 ± 8% for Villa) than in vitro shoot rooting (in quinoa rooting media 3 RQM-3, MS supplemented with 2 mg l−1 IBA: 87 ± 6% for Cahuil and 83 ± 7% for Villa) and subsequent acclimatization (83 ± 7% and 80 ± 7% respectively). Furthermore, ex vitro rooting combines rooting and acclimatization in one step and requires less time. This is the first coastal cultivar micropropagation protocol reported and the starting point for development of other biotechnological tools. A micropropagation protocol has been developed for coastal cultivars of Chenopodium quinoa. Coastal cultivars are vital to increase the cultivation area of quinoa.

Bromus auleticus (Trin.) is a grass native to the southern cone with important agronomical potential as fodder. Different breeding programs have been initiated with this grass, but plant tissue culture techniques could not be used because B. auleticus is recalcitrant. The aim of the present study was to develop a micropropagation protocol in the genus Bromus and to investigate if the association between B. auleticus and Epichloë endophytes affected in vitro culture and growth of micropropagated plantlets. In different micropropagation stages, better results were obtained with endophyte-infected (E+) seeds compared to endophyte-free (E−) seeds. The E+ seeds presented higher percentages of in vitro germination (82 ± 5 vs. 57 ± 6%), callus induction (72 ± 6 vs. 37 ± 6%), and plant regeneration from callus (89 ± 5 vs. 13 ± 5%). We also compared the biomass of shoot complexes and regenerated plantlets. After 4 weeks of culture, shoot complexes obtained from E+ seeds reached greater weight than the ones regenerated from E− seeds (173 ± 24 vs. 74 ± 9 mg). More than the 80% of the regenerated shoot complexes were rooted ex vitro and acclimated, regardless of their origin (E+ or E−). Finally, after 4 weeks of acclimatization, the plantlets regenerated from E+ seeds reached a greater weight than the ones from E− seeds, (461 ± 64 vs. 172 ± 25 mg). These results indicate that the use of endophyte-infected (E+) seeds enhances significantly B. auleticus micropropagation and promotes growth of the regenerated plantlets. Fil: Regalado González, Jose Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Berdion Gabarain, Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Vignale, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Novas, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Pitta Alvarez, Sandra Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Iannone, Leopoldo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina

The argan (Argania spinosa L.) tree is indigenous to southwestern Morocco. Successful introduction of this species in Argentina depends on the degree of climate similarity in the natural area compared to new areas with agroclimatic suitability. Based on international bibliography, the authors outlined an agroclimatic zoning model for this tree in Argentina. To determine agroclimatic suitability, the average climatic data of all the meteorological stations (1981-2010) were analyzed. Climatological characteristics of its region of origin were considered to evaluate the requirements and biometeorological conditions. The maps were obtained using a series of previously interpolated bioclimatic variables. The agroclimatic indices, which determine different classes of suitability, were integrated in a Geographic Information System (GIS) to create thermal and moisture regions. The resulting maps were superimposed to determine the agroclimatic zoning. Eight classes of agroclimatic suitability under dry-subhumid, semiarid, and arid climatic conditions were delineated. There are no optimal zones for the argan tree in Argentina. This work can be updated by further incorporation of complementary information. Argan tree is a promising dryland crop for farmers in semiarid and arid climates of Argentina. This model may be applied in any part of the world, using the agroclimatic limits presented in this paper. Fil: Falasca, Silvia Liliana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Clima y Agua; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Pitta Alvarez, Sandra Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Ulberich, Ana Cristina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Humanas. Centro de Investigaciones Ecogeográficas y Ambientales; Argentina

Italian ryegrass (Lolium multiflorum) is an annual grass considered as one of the most important temperate forage grasses in the world. However, it is recalcitrant to plant tissue culture techniques hindering its genetic manipulation. Epichloë occultans is an endophytic fungus associated with L. multiflorum. This symbiosis causes improvements in physiological and ecological traits of the host plants. The objective of this work was to study the effect of E. occultans on L. multiflorum micropropagation. We compared the response of endophyte-infected (E+) and endophyte-free (E−) seeds in different micropropagation stages. The E+ seeds were more successful than E− seeds in in vitro germination (83 ± 5 vs. 63 ± 6%), callus induction (78 ± 5 vs. 57 ± 6%), callus proliferation (average diameter of 21.5 ± 1.3 mm in two subcultures vs 17.3 ± 0.8 mm in three subcultures) and plant regeneration from callus (83 ± 7 vs. 30 ± 8%). These results indicate that E. occultans enhances significantly L. multiflorum micropropagation. The use of endophyte-infected (E+) seeds can be a solution to make this grass more amenable to different biotechnological tools, such as the genetic transformation. Fil: Regalado González, Jose Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Vignale, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Novas, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Pitta Alvarez, Sandra Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Iannone, Leopoldo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina

The growing biodiesel production requires the use of new technologies and alternative feedstocks to maintain the growing demand of this biofuel. The macaw (Acrocomia aculeata) is a palm native to Argentina whose fruits present high oil content. Due to its tolerance to prolonged drought, it is a promising crop for biodiesel and biokerosene production. The aim of this work was to design an agroclimatic zoning model to define the potential growing areas from macaw in Argentina. To define the agroclimatic suitability to produce oil, it was necessary to identify the requirements, limits, and biometeorological tolerance for this palm. In order to define the agroclimatic fitness of this crop in Argentina, the meteorological data corresponding to the period 1981–2010 were employed. The agroclimatic indices were integrated in a Geographic Information System. The maps were superimposed and the overlapping regions delineated the agroclimatic zoning. The agroclimatic zonation classified zones with homogeneous characteristics responding to bioclimatic requirements of this species, resulting in optimal, very suitable, suitable, and nonsuitable areas for macaw cultivation. The authors designed an agroclimatic zoning model based on bibliography. This model can be used in any part of the world, employing the same agroclimatic indices presented in this work.

Cattle breeding is an important economical activity in Argentina, highly dependent on grass production. In the last decades, grasslands zones were reduced and confined to less productive lands due to the advance of agronomical cultures. Therefore, it is important to develop new strategies to improve forage production. New eco-friendly trends in plant growth promotion include the use of microbial endophytes, but the in vitro studies of plant-bioinoculant interactions is limited by the scarce current technological development. In this work, we use a micropropagation protocol for Lolium multiflorum, developed in a previous work, to study the effect of bacterization with actinobacterial endophytes, isolated from Argentine native grasses, on the growth of L. multiflorum in vitro plantlets. To achieve this objective, L. multiflorum plantlets were inoculated with three Micromonospora strains (SB3, TW2.1 and TW2.2). The results obtained showed that the effect of actinobacterial inoculation depends on the Micromonospora strain used. The inoculation with SB3 promoted plant growth, increasing plant biomass, root length and the rate of plantlets ready to be acclimatized after 4 weeks of in vitro culture. Strain TW2.1 did not show, statistically, differences compared to control treatments, while TW2.2 inhibited plant growth, decreasing plant biomass, root length and the rate of plants ready to acclimatize. Our results showed that Micromonospora strain SB3 could be a good candidate to use in breeding programs for L. multiflorum and other grasses to increase their yield. Fil: Della Mónica, Ivana Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Novas, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Iannone, Leopoldo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Querejeta, Giselle Andrea. Universidad Nacional de General Sarmiento. Instituto de Ciencias. Área de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Scervino, Jose Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Pitta Alvarez, Sandra Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental. Laboratorio de Cultivo Experimental de Microalgas; Argentina Fil: Regalado González, Jose Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental. Laboratorio de Cultivo Experimental de Microalgas; Argentina

Panicum virgatum (swich-grass) is cultivated in some countries to obtain biomass used in the production of heat, fiber, electricity and second generation ethanol. Currently, in Argentina, this species is used for forage and as an ornamental. The aim of this work was to design an agroclimatic zoning model for swich-grass in Argentina, both for upland and lowland ecotypes, based on its bioclimatic requirements and employing a Geography Information System. The variables taken into consideration were: average temperature during growing period and reproductive period, frost free days and rainfall during growing season. This work demonstrated that an ample region of the country is agro-climatically suitable for the implantation of switch-grass in rainfed conditions or with complementary irrigation. The agroclimatic zoning for the upland ecotype shows that suitability reaches latitudes of up to 46ºS, while the lowland ecotype can be grown up to 40ºS. Thornthwaite's Moisture Index equal to zero was overlapped to the Argentinean agroclimatic zoning for upland and lowland types, to obtain the potential growing areas under dry-subhumid, semiarid to arid climates. The areas where switch-grass should be effectively tested are those categorized as optimal, very suitable, suitable, and very suitable/suitable with irrigation, located to the West of TMI equal to zero, which include dry-subhumid (0

Salsola kali is considered extremely valuable as an energy crop worldwide because it adapts easily to environments with strong abiotic stresses (hydric, saline and alkaline) and produces large amounts of biomass in drylands. This species is categorized as an important weed in Argentina. The aim of this work was to design an agro-ecological zoning model for tumbleweed in Argentina, employing a Geography Information System. Based on the bioclimatic requirements for the species and the climatic data for Argentina (1981–2010 period), an agro-climatic suitability map was drawn. This map was superimposed on the saline and alkaline soil maps delineated by the Food and Agriculture Organization for dry climates, generating the agro-ecological zoning on a scale of 1 : 500 000. This zoning revealed very suitable and suitable cultivation areas on halomorphic soils. The potential growing areas extend from N of the Salta province (approximately 22° S) to the Santa Cruz province (50° S). The use of tumbleweed on halomorphic soils under semi-arid to arid conditions, for the dual purpose of forage use and source of lignocellulosic material for bioenergy, could improve agricultural productivity in these lands. Furthermore, it could also contribute to their environmental sustainability, since the species can be used to reclaim saline soils over the years. Based on international bibliography, the authors outlined an agro-ecological zoning model. This model may be applied to any part of the world, using the agro-ecological limits presented here. Fil: Falasca, Silvia Liliana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Clima y Agua; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Pitta Alvarez, Sandra Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina Fil: Ulberich, Ana Cristina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Humanas. Centro de Investigaciones Ecogeográficas y Ambientales; Argentina

Berberis buxifolia Lam., known as “Calafate”, is a plant native to Argentina that exhibits antimicrobial activity. This biological activity is attributed to the isoquinoline alkaloid berberine. The aim of this research was to test the antimicrobial properties of different extracts of this species, taking berberine as the reference molecule, and to examine if the expression of bacterial multidrug resistance (MDR) efflux pumps could be responsible for possible resistance mechanisms. To this end, a wild-type and a mutant strain of Staphylococcus aureus with a defective MDR efflux pump were used and the minimum inhibitory concentrations of the extracts were determined. The studies were carried out with infusions of in vivo shoots and “Calafate” commercial tea, as well as with the media derived from shoot cultures incubated with different plant growth regulators (thidiazuron, picloram, and jasmonic acid). As far as antimicrobial activity is concerned, all the extracts tested were significantly more effective than berberine standard. “Calafate” commercial tea and shoot tea had inhibitory concentrations similar to the one observed for ampicillin standard. The media from the shoot cultures, however, were significantly more effective than all the others, particularly the one derived from jasmonic acid, suggesting the presence of compounds that could be acting synergistically with berberine. There were no differences in antimicrobial activity against the wild-type and the mutant S. aureus; no definite conclusions could be drawn concerning the relationship between MDR pumps and possible pathogen resistance to extracts of B. buxifolia.

One of the major causes of crop stress is soil or water salinity. Thus, selection of the best species for cultivation in semiarid and arid climates is fundamental.Salvadora persica is an evergreen perennial halophyte that can grow under extreme conditions, from very dry environments to highly saline soils.Based on international bibliography, the authors outlined an agro-ecological zoning model to determine the potential cultivation zones for S. persica in Argentina. This model may be applied to any part of the world, using the agro-ecological limits presented in this work. All the maps were developed by the implementation of a geographic information system (GIS) that can be updated by the further incorporation of complementary information, with the consequent improvement of the original database.The overlap of the agroclimatic suitability map on the drylands´ saline soils and the drylands´ alkaline soils maps, determined the agro-ecological zoning. Since some areas in the agro-ecological zoning can overlap with land that is already assigned for other uses, protected areas, current land use/cover of the different zones, and urban areas maps were incorporated into the GIS and subtracted by a mask. This resulted in the delimitation of ?potential cultivation zoning?, thus avoiding possible conflicts surrounding the use of land and making the agro-ecological zonation more efficient.There is a broad agro-ecological zone for cultivation of S. persica that extends from Northern Argentina to approximately 41° South latitude, under dry-subhumid to semiarid climates. Lands classified with different degrees of suitability in the potential cultivation zoning could be used for production of this species for energy purposes on lands that are either unsuitable for food production or currently assigned for other purposes.This paper represents pioneering work since there are no previous studies concerning the introduction of S. persica in Argentina. Fil: Falasca, Silvia Liliana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Clima y Agua; Argentina Fil: Miranda del Fresno, Ma. Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Humanas. Centro de Investigaciones Ecogeográficas y Ambientales; Argentina Fil: Pitta Alvarez, Sandra Irene. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Argentina de la Empresa. Facultad de Ingeniería y Ciencias Exactas. Instituto de Tecnología; Argentina

Fil: Pitta Alvarez, Sandra Irene. Universidad de Buenos Aires. Facultad de Farmacia y Bioquimica. Departamento de Microbiologia, Inmunologia y Biotecnologia. Catedra de Microbiologia Industrial y Biotecnologia; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas; Argentina

The effects of chitosan, acetic acid and citric acid on production and release of hyoscyamine and scopolamine in hairy root cultures of Brugmansia candida were studied. Chitosan and acetic acid were tested at different concentrations and also at different media pH values. At pH 5.5, and at certain concentrations, acetic acid and chitosan increased the content of root scopolamine and hyoscyamine, and promoted the release of both alkaloids. Lowering the pH to 3.5 and 4.5 reduced the accumulation of both alkaloids in the roots, but at a pH of 4.5, their release increased significantly. Acetic and citric acid stimulated the release of scopolamine and hyoscyamine.

Brugmansia candida, an indigenous South American plant, produces the tropane alkaloids scopolamine and hyoscyamine, which are widely employed in medicine as anticholinergic agents. In this research, hairy roots of Brugmansia candida, obtained through infection with Agrobacterium rhizogenes LBA 9402, were employed to produce these tropane alkaloids in vitro. The effects of different concentrations of GA7 on kinetics of growth and alkaloid accumulation on two different hairy root clones of B. candida were analyzed, and the influence of GA7 on the number of new branches and rates of elongation was also studied. On clone 7A, GA7 at concentrations of 10−4, 10−1, and 1 mg/l increased the exponential growth rate. Levels of 10−1 and 10−4 mg/l GA7 elevated the scopolamine/hyoscyamine (S/H) ratios in the early phases of growth, but the sum of scopolamine plus hyoscyamine per flask (S + H) decreased during that period. When 1 mg/l GA7 was used, the highest S/H ratios were observed in late exponential/early stationary phases, but the highest S + H totals were obtained in mid-exponential phase. GA7 at levels of 10−1 and, especially, 1 mg/l exerted a positive effect on formation, emergence, and rate of elongation of lateral roots (clone 7A). On clone 7B, levels of 10−1 and 1 mg/l GA7 did not alter significantly the exponential growth rate. GA7 in concentrations of 10−1 mg/l induced increases in both S/H ratio and S + H totals in late phases of growth.

Brugmansia candida hairy roots, obtained by infection withAgrobacterium rhizogenes LBA 9402, exhibit, after subculturing in liquid media, a tendency towards dedifferentiation. It has been found that the following strategies can be applied to inhibit this dedifferentiation and preserve normal root morphology: (a) lowering both the mineral and sucrose concentration in the media employed so as to diminish osmotic stress (a condition to which these roots appear to be particularly susceptible); (b) employing antiauxins in appropriate concentrations; and (c) maintaining the hairy roots on solid media prior to use in production processes in liquid media. The first strategy suggested does not favor alkaloid productivity, but in this case a two-step method could be attempted: biomass with normal root morphology could be obtained in a first stage using low sucrose concentrations, and in a second stage, sucrose could be increased in order to achieve higher productivity. In all the clones ofB. candida obtained, alkaloid production was biased towards scopolamine.

Hairy roots of Brugmansia candida that grew without agitation were obtained. Kinetics of growth and production of the tropane alkaloids scopolamine and hyoscyamine, with and without agitation, were studied. The exponential growth rate was higher in the roots that were exposed to shaking (0.13 d(-1)) than in the nonagitated ones (0.09 d(-1)). The specific production and the levels per flask of both alkaloids were enhanced without shaking. The use of these roots in large-scale productions could be economically advantageous. It remains to be seen if the data obtained in shake flasks can be extrapolated to large-scale bioreactors.

In vitro cultures of Berberis buxifolia were established using thidiazuron (4.5, 23 and 45 mM) or picloram (4 and 40 mM) as plant growth regulators for sustaining growth. For producing berberine, a two-stage culture was performed. In the first step, thidiazuron or picloram were used for biomass production followed by the production stage where benzylaminopurine (4.4 mM) was added as a plant growth regulator. Berberine yields (102 mg g(-1) DW) and in vitro shoot cultures (200 mg g(-1) DW) were significantly lower than those of whole plants in the field (416 mg g(-1) DW). The highest productivity (0.18 mg 1(-1) day(-1)) was attained using picloram (either 4 on 40 mM) in the first stage for producing biomass.

Scopolamine and hyoscyamine are tropane alkaloids employed in medicine as antispasmodics, preoperative medication and for the treatment of motion sickness. Since their chemical synthesis is difficult and expensive, these compounds are still extracted from plants that belong to several species of the Solanaceae. In this research, a biotechnological system for the production of both alkaloids was employed. Hairy roots of Brugmansia candida (syn. Datura candida), obtained through transformation with the soil pathogen Agrobacterium rhizogenes, were cultured in vitro. In an attempt to increase the productivity of the cultures, they were exposed to biotic elicitors (hemicellulase and homogenized B. candida roots) and stress agents (CuSO4). It was observed that hemicellulase had a positive effect on scopolamine (2-fold increase) and, especially, hyoscyamine accumulation (4-fold increase) in the roots. The homogenized roots also had a positive effect on alkaloid accumulation in the roots throughout the experiment (approximately 2.5-fold). The main effects of CuSO4 were seen in the release of alkaloids to the medium, particularly at 24 and 48 (6 to 10-fold increase). © 1998 John Wiley & Sons, Ltd.

Hairy roots of Brugmansia candida produce the tropane alkaloids scopolamine and hyoscyamine. In an attempt to divert the carbon flux from competing pathways and thus enhance productivity, the polyamine biosynthesis inhibitors cyclohexylamine (CHA) and methylglyoxal-bis-guanylhydrazone (MGBG) and the phenylalanine-ammonia-lyase inhibitor cinnamic acid were used. CHA decreased the specific productivity of both alkaloids but increased significantly the release of scopolamine (approx 500%) when it was added in the mid-exponential phase. However, when CHA was added for only 48 h during the exponential phase, the specific productivity of both alkaloids increased (approx 200%), favoring scopolamine. Treatment with MGBG was detrimental to growth but promoted release into the medium of both alkaloids. However, when it was added for 48 h during the exponential phase, MGBG increased the specific productivity (approx 200%) and release (250- 1800%) of both alkaloids. Cinnamic acid alone also favored release but not specific productivity. When a combination of CHA or MGBG with cinnamic acid was used, the results obtained were approximately the same as with each polyamine biosynthesis inhibitor alone, although to a lesser extent. Regarding root morphology, CHA inhibited growth of primary roots and ramification. However, it had a positive effect on elongation of lateral roots.

The polyamine, cadaverine, was detected in transformed root cultures of Brugmansia candida (syn. Datura candida), a Solanaceae which produces the tropane alkaloids scopolamine and hyoscyamine. To the best of our knowledge, this is the first time that the existence of this uncommon polyamine has been detected in a Datura species. Cadaverine, however, could not be found in the whole plant. The occurrence of cadaverine in hairy roots could be a consequence of either the transformation or a response to stress. Also, cadaverine could be participating in other secondary pathways rather than to the tropane alkaloids. The common polyamines, putrescine, spermidine and spermine were also observed.