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Germination and in vitro regeneration of S. punicea and S. virgata calluses were studied to produce an efficient protocol for subsequent use as phytoremediator species and provide information to increase contamination tolerance. Mechanical and chemical scarification, as pre-germination treatments, increased germination in both species. In vitro regeneration is possible, using epicotyl sections as explant, which have caulogenic capacity. However, S. virgata had a better response at the rooting stage. This provides new information to advance in genetic transformation studies to increase contamination tolerance for these species to be used in phytoremediation or revegetation plans.

The objective of the study was to evaluate the biometry of fruits and seeds of S. punicea in order to determine the point of collection for production of seedlings of the species. The fruits of S. punicea were collected from plants in situ in Barra do Ribeiro, RS. In the laboratory, they were separated by staining in: stage 1, 2 and 3. Fruits and seeds were measured with digital caliper (mm), counting the number of seeds and locules. At each stage water content, seed dry matter and germination test were evaluated. For this last one, four replications of 25 seeds were placed in germination chamber during 16 days, photoperiod of 12 hours and temperature of 25oC. The variables analyzed were germination, germination speed index, average germination time, percentage of normal and abnormal seedlings, and hard seeds. It was observed that in stage 2 the seeds have larger dimensions, a higher percentage of germination and formation of normal seedlings, and a higher rate of germination speed. It is concluded that fruits must be harvested at stage 2 of maturation, as seeds have the highest rates of germination and normal seedlings, as well as the lowest rates of insect damage.

Knowledge on alien species is needed nowadays to protect natural habitats and prevent ecological damage. The presence of new alien plant species in Italy is increasing every day. Calabria, its southernmost region, is not yet well known with regard to this aspect. Thanks to fieldwork, sampling, and observing many exotic plants in Calabria, here, we report new data on 34 alien taxa. In particular, we found three new taxa for Europe (Cascabela thevetia, Ipomoea setosa subsp. pavonii, and Tecoma stans), three new for Italy (Brugmansia aurea, Narcissus &lsquo, Cotinga&rsquo, and Narcissus &lsquo, Erlicheer&rsquo, ), one new one for the Italian Peninsula (Luffa aegyptiaca), and 21 new taxa for Calabria (Allium cepa, Asparagus setaceus, Bassia scoparia, Beta vulgaris subsp. vulgaris, Bidens formosa, Casuarina equisetifolia, Cedrus atlantica, Chlorophytum comosum, Cucurbita maxima subsp. maxima, Dolichandra unguis-cati, Fagopyrum esculentum, Freesia alba, Juglans regia, Kalancho&euml, delago&euml, nsis, Passiflora caerulea, Portulaca grandiflora, Prunus armeniaca, Prunus dulcis, Solanum tuberosum, Tradescantia sillamontana, and Washingtonia filifera). Furthermore, we provide the first geolocalized record of Araujia sericifera, the confirmation of Oxalis stricta, and propose a change of status for four taxa (Cenchrus setaceus, Salpichroa origanifolia, Sesbania punicea, and Nothoscordum gracile) for Calabria. The updated knowledge on the presence of new alien species in Calabria, in Italy and in Europe could allow for the prevention of other new entries and to eliminate this potential ecological threat to natural habitats.

The exotic shrub red sesbania is an increasingly problematic weed in riparian and wetland ecosystems of California. Current control methods focus on manual removal, followed by herbicide application. Although this method effectively removes mature stands, the control is temporary because the presence of a large seed bank results in rapid germination and growth of new seedlings. We measured the density of seed banks beneath stands of varying densities and evaluated the potential of tarping and inundation for control of red sesbania seed banks. As expected, the abundance of viable red sesbania seeds in the soil was significantly greater beneath high-density stands than it was beneath low-density stands. Results for inundation and tarping experiments were mixed. Sustained inundation significantly decreased survivorship of germinated seeds compared with the control, as well as causing a statistically significant reduction in germination. Seven months after tarping, during the fall/winter growing season, there was no significant effect on red sesbania seedling abundance, stump resprout abundance, or height. Germination in the laboratory was significantly reduced by extended exposure to temperatures of 60 C, although lower temperatures did not reduce germination. Red sesbania appears to be resilient to tarping as a control method, at least in the settings studied.

La vegetación ribereña desempeña un rol importante en el control de fuentes no puntuales de contaminación y contribuye a la consiguiente mejora de la calidad del agua de ríos y arroyos. El río Matanza-Riachuelo ha sido clasificado como uno de los más contaminados del mundo, registrándose concentraciones elevadas de metales y otros contaminantes en la columna de agua y en los sedimentos de sus riberas. El objetivo de este trabajo consistió en realizar una caracterización física, química y florística y poner a prueba una intervención para la rehabilitación ecológica en un área piloto de la ribera del río Matanza-Riachuelo. Se determinaron cromo, cadmio, níquel, zinc, cobre y plomo en muestras de sedimentos ribereños y en muestras de las herbáceas Sagittaria montevidensis y Tradescantia fluminensis. Los suelos presentaron muy alto grado de contaminación, fundamentalmente debido a los elevados valores de cromo, cobre y zinc. Ambas herbáceas toleraron la variación del nivel del agua y acumularon metales, principalmente en sus estructuras subterráneas. Estas características indicaron que S. montevidensis y T. fluminensis podían ser utilizadas en intervenciones para la rehabilitación de riberas. La rehabilitación consistió en la plantación directa de 45 ejemplares de árboles y arbustos nativos con tolerancia al estrés ambiental (Erythrina crista-galli, Senna corymbosa, Solanum granulosum-leprosum, Allophylus edulis, Syagrus romanzoffiana, Salix humboldtiana, Lantana camara, Cestrum parqui y Sesbania punicea); en la línea de costa se instalaron 66 biorrollos para la implantación de las helófitas nativas: Hydrocotyle bonariensis, Tripogandra diuretica, T. fluminensis, Schoenoplectus californicus, S. montevidensis y Echinodorus grandiflorus. El monitoreo posterior demostró que los árboles y arbustos toleraron tanto los niveles de contaminación de los suelos como el prolongado periodo de inundación. La implantación de macrófitas S. californicus, S. montevidensis y E. grandiflorus mediante la técnica de biorrollos fue una alternativa eficaz pero los helófitos rastreros: H. bonariensis, T. fluminensis y T. diuretica resultaron afectados fundamentalmente por el depósito de basura flotante., Riparian vegetation plays an important role in the control of non-point sources of pollution and the improvement of the water quality of rivers and streams. The Matanza-Riachuelo River has been classified as one of the most polluted in the world, according to high levels of metals and other pollutants in the water column and in the sediments of its banks. The objective of this work was to carry out a physical, chemical and floristic characterization and to test an intervention for ecological rehabilitation in a riparian pilot area of the Matanza-Riachuelo River. Chromium, cadmium, nickel, zinc, copper and lead were determined in sediment and samples of the herbaceous: Sagittaria montevidensis and Tradescantia fluminensis. Both herbaceous plants tolerate the variation of water level and accumulate metals, mainly in their underground structures. These characteristics indicate that S. montevidensis and T. fluminensis could be used in the rehabilitation of banks. The rehabilitation consisted in the direct planting of 45 specimens of native trees and shrubs tolerant to environmental stress (Erythrina crista-galli, Senna corymbosa, Solanum granulosum-leprosum, Allophylus edulis, Syagrus romanzoffiana, Salix humboldtiana, Lantana camara, Cestrum parqui y Sesbania punicea), in the coastal line were installed 66 prevegetated rolls for the implantation of the native helophytes: Hydrocotyle bonariensis, Tripogandra diuretica, T. fluminensis, Schoenoplectus californicus, S. montevidensis y Echinodorus grandiflorus. The subsequent monitoring showed that the trees and shrubs tolerated both the levels of soil contamination and the prolonged period of flooding. The implantation of macrophytes (S. californicus, S. montevidensis y E. grandiflorus) by the technique of prevegetated rolls proved to be a good alternative, but the helophytes: H. bonariensis, T. fluminensis y T. diuretica were affected mainly by depositing floating debris., Instituto de Limnología "Dr. Raúl A. Ringuelet"

Red mud (RM) residue and the toxicity thereof have become a serious threat worldwide as it contaminates the environment. The identification of potential plant species for the remediation of RM deposits may help to abate contamination toward achieving environmental conservation. Biodiversity assessment of naturally growing plant species on RM deposits provides a scenario of species adaptation and succession. Potential plant species can be identified on the basis of their phytosociological characteristics, including importance value index (IVI), frequency, and dominance. Species of economic importance may be selected for this developing niche. In this chapter, RM problems and its phytoremediation with potential plant species toward a quality environment around RM deposits are discussed. Species differ in their ability to remediate metal toxicity by accumulating different magnitudes of toxic metals in their biomass. Sonchus asper, Sesbania punicea, Launaea asplenifolia, Saccharum bengalense, and Populus tremuloides were identified as potential plant species for use on RM deposits for remediation. Among these, S. bengalense is an ecologically and socioeconomically important tall grass that supports the colonization and development of other species during ecological succession on RM deposits.

Angelonia integerrima Spreng. (Plantaginaceae), Campomanesia aurea O. Berg (Myrtaceae) e Sesbania punicea (Cav.) Benth (Fabaceae) são espécies nativas do Rio Grande do Sul, que devido a características como o porte, arquitetura, coloração e aroma das flores, são classificadas como plantas ornamentais de uso potencial. O presente trabalho teve como objetivo caracterizar citogeneticamente diferentes populações de A. integerrima, C. aurea e S. punicea quanto ao número cromossômico, índice meiótico, viabilidade e germinação dos grãos de pólen e conteúdo nuclear (2C) de DNA. Para tanto, foram realizadas coletas do material a campo em diferentes localidades de seis municípios do Rio Grande do Sul - Brasil. O número cromossômico foi determinado pelo método de Feulgen, enquanto o índice meiótico e a estimativa da viabilidade polínica foram obtidos pelo método de esmagamento de anteras com diferentes corantes. A germinação in vitro dos grãos de pólen foi avaliada em diferentes meios de cultura (M1, M2 e M3) e temperaturas (20 e 30 ºC). Por fim, estimou-se o conteúdo de DNA nuclear utilizando-se citometria de fluxo a partir de tecidos foliares e de sementes. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste LSD. Quando os mesmos não apresentaram normalidade, foram analisados por Kruskal-Wallis e teste de Dunn. Angelonia integerrima apresenta número cromossômico somático de 2n = 20, índice meiótico e viabilidade polínica superiores a 90 %. Campomanesia aurea teve seu número cromossômico somático determinado pela primeira vez, sendo este de 2n = 22, apresenta índice meiótico médio de 93,6 %, número médio de anteras por flor de 144,2 e viabilidade polínica com variação de 83,4 a 98,9 %. Sesbania punicea apresenta número cromossômico somático de 2n = 12 e gamético n = 6 cromossomos, índice meiótico e viabilidade polínica com média de 98,8 %. Angelonia integerrima, Campomanesia aurea e Sesbania punicea diferem quanto ao requerimento de micronutrientes para a germinação in vitro dos grãos de pólen, sendo a temperatura de 30 ºC a mais adequada para as três espécies. Com relação ao conteúdo de DNA nuclear (2C), estimou-se o valor de 1,43 pg para A. integerrima, 0,97 pg para C. aurea e 1,55 pg para S. punicea. Os resultados encontrados para as populações analisadas das três espécies indicam que as mesmas apresentam estabilidade quanto ao número cromossômico, regularidade durante o processo de microsporogênese, alta viabilidade polínica e germinação satisfatória dos grãos de pólen. Angelonia integerrima Spreng. (Plantaginaceae), Campomanesia aurea O. Berg (Myrtaceae) and Sesbania punicea (Cav.) Benth (Fabaceae) are native species of Rio Grande do Sul, due to characteristics such as size, architecture, coloration and flower scent, are classified as ornamental plants of potential use. The present work aimed to characterize cytogenetically different populations of A. integerrima, C. aurea and S. punicea regarding chromosome number, meiotic index, viability and pollen grain germination and nuclear content (2C) of DNA. Thus, field material was collected at different locations in six municipalities of Rio Grande do Sul - Brazil. The chromosome number was determined by the Feulgen stain method, while the meiotic index and the estimate of pollen viability were obtained by squashing anthers with different stains. In vitro germination of pollen grains was evaluated in different culture media (M1, M2 and M3) and temperatures (20 and 30 ºC). Finally, nuclear DNA content was estimated using flow cytometry from leaf and seed tissues. Data were subjected to analysis of variance and means compared by LSD test. When they did not show normality, they were analyzed by Kruskal-Wallis and Dunn's test. Angelonia integerrima has a somatic chromosome number of 2n = 20, meiotic index and pollen viability greater than 90 %. Campomanesia aurea has its somatic chromosomal number determined for the first time, this being 2n = 22, has a medium meiotic index of 93.6 %, average number of anthers per flower of 144.2 and pollen viability ranging from 83.4 to 98.9 %. Sesbania punicea has a somatic chromosome number of 2n = 12 and gametic n = 6 chromosomes, meiotic index and pollen viability with an average of 98.8 %. Angelonia integerrima, Campomanesia aurea and Sesbania punicea differ in the requirement of micronutrients for in vitro germination of pollen grains, being the temperature of 30 ºC the most appropriate for the three species. Regarding the content of nuclear DNA (2C), it was estimated 1.43 pg for A. integerrima, 0.97 pg for C. aurea and 1.55 pg for S. punicea. The results found for the populations analyzed of the three species indicate that they present stability regarding chromosome number, regularity during the microsporogenesis process, high pollen viability and satisfactory pollen grain germination.

The aim of this work was to verify the in vitro germination of pollen grains of Angelonia integerrima L., Campomanesia aurea O. Berg and Sesbania punicea (Cav.) Benth in different culture medium and temperatures. For this purpose, flower buds from which pollen was collected and sprayed on plates containing the three evaluated culture medium: M1 - agar and sucrose; M2 - agar, sucrose and H3BO3; M3 - agar, sucrose, H3BO3, Ca(NO3), MgSO4 and KNO3; and two incubation temperatures (20 °C and 30 °C). Data was subjected to analysis of variance after its transformation to square root and means were compared by Fisher’s test (LSD). For the three species, the temperature of 30 ºC provided the highest percentage of pollen grain germination. For A. integerrima, M1 and M3 promoted the highest germination percentages (40.7 % and 56.5 %, respectively). On the other hand, for C. aurea, M2 provided the highest germination average (43.7 %). At last for S. punicea, M3 was the one that provided the highest average (31.62 %). It was concluded that the evaluated species differ in micronutrient requirements for in vitro germination of pollen grains. The temperature of 30 °C was suitable for all three species.

Sesbania punicea (Cav.) Benth. has been recommended for the recovery of degraded areas. This study aimed at verifying the effect of salinity in the germination of S. punicea seeds in different hydric and luminosity conditions and assessing the influence of salinity and flooding on the growth and concentration of photosynthetic pigments. After the morphometric measurements of the fruits and seeds, we performed germination tests in different salt concentrations (0,5, 10 and 15gL-1 NaCl), keeping the seeds in a humid substrate (normoxy) or submerged (flooding), in the presence or absence of luminosity. There was a decrease in the percentage of germination and germination speed index (GSI) of seeds that were kept submerged in the dark. The average germination time (AGT) decreased up to the concentration of 10gL-1NaCl when the seeds were submitted to submersion in the presence of light. The growth and the production of leaves of seedlings exposed to flooding decreased as the salt concentration increased. The concentrations of photosynthetic pigments of seedlings of S. punicea did not differ among the treatments. Therefore, the colonization and occupation of new degraded areas by S. punicea may be limited by the presence of salts concentrations in the soil.

This paper contributes to the relatively sparse literature on the effects of insect herbivory on the population dynamics of plants and is probably unique in that it reports the long-term effects of combinations of three insect herbivore species on the population densities of a moderately long-lived tree species. The tree is Sesbania punicea, a leguminous perennial from South America that has been the target of a biological control programme in South Africa for almost 20 years. Sixteen infestations of the weed have been monitored for periods of up to 10 years to determine changes in the density of the mature, reproductive plants under the influence of different combinations of three biological control agents (i.e. with one, two or three of the agent species present in the weed infestation). The three biological control agents, all weevil species, include Trichapion lativentre, which primarily destroys the flower-buds, Rhyssomatus marginatus, which destroys the developing seeds, and Neodiplogrammus quadrivittatus, whose larvae bore into the trunk and stems of the plants. While T. lativentre occurs throughout the range of the weed in South Africa, the other two species are less mobile, more recent introductions and are largely confined to the vicinity of selected release sites. There has been a significant decline in the density of mature S. punicea in areas where two or more of the agents are established. The decline of the weed has been most evident where N. quadrivittatus is active and particularly so where both of the other two weevil species are also present.

Belonging to the family Fabaceae, Sesbania punicia and S. virgata are characterized by their ecological potential in the recovery of degraded areas. The present study aimed to describe the physical, morphobiometric characteristics of seeds, the germination phases and the initial development of S. punicia and S. virgata seedlings, as well as the germination behavior of seeds at different temperatures and substrates. For the physical characterization of seeds, the weight of one thousand seeds, number of seeds per kilogram, dry biomass of one thousand seeds and the moisture content were determined. To evaluate the effect of substrate and temperature on germination, the experiment was conducted in a completely randomized design, using a 3 x 3 factorial scheme, three substrates (sand, vermiculite and blotting paper) and three temperatures (20, 25 and 30 °C). The following factors were evaluated: germination percentage, germination speed index, mean germination time and synchronization index. S. punicea presented 13,243 seeds and S. virgata presented 14,414 seeds per kilogram, with moisture content of 14.5 and 7.9 %, respectively. Both species present similar morphobiometry and seedling development. For S. punicea, the blotting paper substrate and the temperature of 25 °C were most efficient for germination. For S. virgata, all treatments were effective for germination.

Los eventos de El Niño en Piura, Perú, se presentan con una frecuencia entre 8 y 15 años, como han sido los tres últimos fenómenos considerados como muy fuertes, 1983, 1998, 2016. Estos fenómenos traen consigo presencia de lluvias que ocasionan daños significativos en la infraestructura de la región, muchos son los parámetros para evaluar los daños ocasionados, sin embargo la historia de nuestro País nos demuestra que los antepasados aprovecharon de la mejor manera la presencia de las lluvias. Los estudios de investigación actuales demuestran la gran importancia que tiene la presencia de estas lluvias, ambas teorías la ancestral y la moderna coinciden con la apuesta de la naturaleza por demostrarnos la teoría de GAIA, especialmente en la conservación de la biodiversidad existente en los bosques secos de nuestra región. La agricultura de nuestra zona se ve muy afectada por la presencia del fenómeno del niño, este tipo de agricultura tiene una cedula de cultivos que son para el auto consumo y la creciente siembra de especies que las demanda el mercado de exportación con clientes que cada vez son más exigentes en cultivos producidos con tecnología orgánica.Los paquetes tecnológicos con los que contamos en la región siempre han estado orientados a un tipo de producción solamente con insumos químicos esto por diferentes motivos, uno de ellos es que no se dispone de variables prácticas que sean incluidas en este paquete tecnológico. Durante la presencia del último fenómeno del niño costero se organizó tareas de incursión al bosque seco con el objetivo de observar que nos brinda el bosque seco para mejorar el paquete tecnológico de la cedula de cultivos actuales. Como experiencia del autor se tenía que en el año 1984, observó la presencia de una especie de leguminosa con alto grado de nodulación en sus raíces, Hoy 2017, se ha determinado la presencia de áreas significativas de leguminosa conocida como Sesbania sesban, que nos podría facilitar el recojo de semilla para ser introducida como variable en el paquete tecnológico actual. La Sesbania sesban es una especie reconocida en el ámbito internacional como una excelente fuente de abono verde y el uso complementario a través de energía calorífica, forraje para el ganado y alimentación (flores) en los seres humanos.

Naturally growing Sesbania species with tolerance to unfavourable habitats are widely distributed in non-cultivated seasonally wetland areas in Uruguay. We investigated the relative abundance, diversity and symbiotic efficiency of Sesbania punicea and S. virgata rhizobia in three ecologically different undisturbed and water-logged sites in Uruguay. Numbers of native-soil rhizobia infective on S. punicea or S. virgata were low, with higher numbers associated with the presence of S. virgata. Plants of S. virgata inoculated with soil suspension showed aerial and nodule biomass greater than that obtained with S. punicea. The rhizobia nodulating Sesbania species in water-logged lands in different regions of Uruguay were diverse differing in growth rates, acid production, growth at 39°C and in LB medium, host range and symbiotic efficiency. Seventeen representative strains clustered into four groups on the basis of phenotypic characteristics, ARDRA and DNA fingerprinting (GTG5-PCR). Partial sequence of 16S rRNA from eight of these strains classified them into at least two genera with four species: Azorhizobium doebereinerae, Rhizobium sp. related to R. etli and two different Rhizobium sp.-Agrobacterium. Our results confirm the presence of the specie Azorhizobium doebereinerae as microsymbionts of S. virgata in South America. No strain of Rhizobium etli has previously been reported as a microsymbiont of Sesbania, though R. etli like organisms have also been recovered from Dalea purpurea and Desmanthus illinoensis. Significant increases in dry matter production were obtained with S. virgata plants inoculated with selected rhizobial strains under growth chamber conditions.

Sesbania punicea (Cav.) Benth. ��� Algajola: marais rud��ralis�� le long de la RN197 pr��s de la ville, esp��ce localement dominante, surtout en bordure des fourr��s d��� Arundo donax L., 4.9.201 2, Tison, J.-M. s.n. (Hb. priv��); Galeria: le long du CD81 un peu au nord du pont aux Cinq Arches, quelques jeunes exemplaires parmi les cistes, issus par semis d���une rang��e d���individus plant��s devant un camping, 24.8.201 2, Tison, J.-M. s.n. (Hb. priv��); 1,2 km au nord-est de Galeria, en arri��re du cordon littoral de galets, en rive droite du diverticule aboutissant dans le cours terminal du Fango, sur une basse terrasse alluviale inondable, �� substrat argilo-limoneux, une trentaine de pieds, certains de 2,5 m de haut et la plupart en fleurs, 30.6.201 1, Paradis, G. & C. Piazza observations et photos. L���esp��ce n�����tait signal��e jusqu���ici que par 2 observations d���un jeune individu chacune (LAMBINON, Candollea 46: 175- 226, 1991; ibid., Candollea 51: 515-557), la seconde d��j�� �� Galeria sans pr��cisions, mais probablement �� un autre endroit car l���auteur ne mentionnait aucune plantation. Des trois stations cit��es ici, celle du Pont des Cinq Arcades (��Arches��) souffre de la s��cheresse et n���est pas dynamique, mais se trouve f��cheusement proche du lit d���un affluent du Fango; celle d���Algajola, cern��e par la ville, est probablement vou��e �� la destruction, mais constitue un bel exemple de ce que pourrait donner cette esp��ce hygrophile envahissante dans les marais littoraux de l�����le. Les exemplaires florif��res de la deuxi��me station ne mesurent que 0,7 �� 2,5 m sous le climat de la Corse, et non 1-4 m comme indiqu�� par JEANMONOD & GAMISANS (Fl. Corsica (ed. 2): 455, 2013), ce qui ne les emp��che pas de se multiplier et de former des buissons denses. La troisi��me station, proche de la mer, para��t ��tre la station la plus riche en individus et devra ��tre surveill��e attentivement., Published as part of Jeanmonod, Daniel, 2015, Notes �� la flore de Corse, XXV, pp. 109-140 in Candollea 70 (1) on page 131, DOI: 10.15553/c2015v701a10, http://zenodo.org/record/5720895

Summary Sesbania punicea (Cav.) Benth. (Fabales: Fabaceae) plants in a field border surrounding a cotton field were sampled for Chinavia hilaris (Say) (Hemiptera: Pentatomidae) to determine if this leguminous shrub served as a host for this stink bug. Chinavia hilaris adults and nymphs fed on fruit of this plant, and nymphs developed on the plant. This is the first record of S. punicea as a host for this stink bug.

The leguminous Acacia caven, Erythrina crista-galli, Enterolobium contortisiliquum, Prosopis affinis and P. nigra nodulated with rhizobial strains isolated from other legume trees; therefore they were considered to be promiscuous (poorly specific) for nodulation. Sesbania punicea and Parapiptadenia rigida did not nodulate with the different strains, indicating a significant specificity for nodulation. A. caven was promiscuous for nodulation and nodulated with both fast- and slow-growing strains of rhizobia and our data suggest that the most efficient strains would be fast-growing rhizobia. A. caven was specific for effectivity since the amount of N2 which was fixed markedly depended on the strain. The relative efficiency (RE) of 6 out of the 11 strains used was higher than 0.80, suggesting they had an active uptake hydrogenase. Ac5, a strain isolated from A. caven, exhibited the highest N2-fixing ability and highest NE (nodule efficiency) when inoculated on its host and also had the highest RE. Shoot dry weight and acetylene reducing activity (ARA) were significantly correlated with the amount of N2 fixed (determined by the total nitrogen difference method), indicating that any of these methods could be used for screening the strains according to their ability to fix N2. The relative efficiency was not correlated with any of these parameters.

Neodiplogrammus quadrivittatus (Oliver) and Trichapion lativentre (Beguin-Billecocq) are 2 South American weevils successfully used for the biological control of Sesbania punicea (Cavanille) Benth. in South Africa. The potential of these insects as control agents for the weeds Sesbania exaltata (Raf.) Rydb. and S. drummondii (Rydb.) Cory in the United States was studied in Argentina. Estimation of adult consumption, the food preference of adult insects on 5 species of Sesbania (3 native hosts and the 2 weeds mentioned above), the capacity of the insects to complete their life cycle on the weeds, and the weed infestation by wild populations in the laboratory garden were studied. The consumption of N. quadrivitattus on both north American weeds did not differ from that on native hosts. Similar consumption was observed for T. lativentre feeding on S. drummondii. S. exaltata showed the lowest consumption. The feeding preference of N. quadrivittatus was similar to that of its natural host plants. In the case of T. lativentre, results on only S. drummondii were comparable to that of its natural hosts. Both insects were able to complete their life cycles on the weeds. In the garden, there was a marked preference by the weevils for S. drummondii. S. exaltata was not attacked by T. lativentre and no test was carried out with N. quadrivittatus. We concluded that both insects are good biocontrol candidates for S. drummondii, whereas only N. quadrivittatus is a promising control agent for S. exaltata.

Sesbanimide and extracts made from ground powders of whole Sesbania punicea and S. bispinosa seeds and isolated embryos and testae of S. punicea inhibited the germination of vegetable, grass and weed seeds. This inhibition was more noticeable on seedling growth than on germination. The inhibitory effect was not transitory but was manifested even after transplanting the seedlings. In all cases, the roots were more sensitive than the shoots and their growth was severely retarded. The inhibitory effect was also detected if the test seeds were soaked in extracts prior to sowing. Embryo and testa extracts of S. punicea gave an inhibitory response. The former was the most inhibitory. This inhibition may partly explain why S. punicea forms dense, uniform stands when invading natural vegetation. There appears to be a strong allelopathic effect expressed by the seed extracts. This warrants further investigation.

In South Africa, a bud-feeding apionid weevil, Trichapion lativentre (Beguin Billecocq), is one of three introduced insect herbivores that are responsible for the successful biological control of Sesbania punicea (Cav.) Benth., a leguminous weed of South American origin. With few exceptions, the annual seed crop of S. punicea has declined by more than 98% since T. lativentre became established on the weed during the late 1970s. However, there are several localized infestations of S. punicea in the Olifants river valley where T. lativentre has been much less successful than elsewhere in the country, and where pod and seed production by S. punicea is still prolific. In this valley, S. punicea often occurs in close proximity to citrus orchards, many of which are sprayed with organophosphate insecticides in spring and early summer (August–October). In the vicinity of sprayed citrus orchards, populations of T. lativentre remained low during the early summer (the main period of bud-burst for S. punicea ) and weevil numbers only increased later, when insecticide treatments in the orchards had almost ceased. As a result, the incidence of damaged flower-buds was lowest, and pod production was highest, on S. punicea plants in the vicinity of sprayed citrus orchards. The negative effects of the insecticides, as measured by higher levels of pod production on the weed, decreased exponentially with increasing distance up to 300 m from the nearest sprayed orchard.

Red sesbania is an invasive South American shrub that has rapidly expanded its range along California waterways, emphasizing the need to prioritize eradication sites at a regional scale. To accomplish this, we updated baseline location data in summer 2010 using field surveys throughout the state. We collected relevant GPS attribute data for GIS analysis and eradication prioritization modeling. The regional survey identified upstream and downstream extents for each watershed, as well as outliers in urban areas. We employed the Weed Heuristics: Invasive Population Prioritization for Eradication Tool (WHIPPET) to prioritize red sesbania sites for eradication, and revised the WHIPPET model to consider directional propagule flow of a riparian species. WHIPPET prioritized small populations isolated from larger infestations, as well as outliers in residential areas. When we compared five experts’ assessments of a stratified sample of the red sesbania populations to WHIPPET’s prioritization results, there was a positive, but nonsignificant, correlation. The combination of WHIPPET and independent expert opinion suggests that small, isolated populations and upstream source populations should be the primary targets for eradication. Particular attention should be paid to these small populations in watersheds where red sesbania is a new introduction. The use of this model in conjunction with evaluation by the land manager may help prevent the establishment of new seed sources and protect uninfested riparian corridors and their adjacent watersheds.

Sesbanimides are cytotoxic compounds, originally isolated in 1983 from seeds of the leguminous plants Sesbania drummondii and Sesbania punicea. In this paper we describe the bacterial production of sesbanimides by two "marine Agrobacterium"; strain PH-103 which produces Sesbanimide-A and strain PH-A034C which produces Sesbanimide-C. The isolation and taxonomy of the producing microorganisms, fermentation and isolation of sesbanimides are reported.

A seed-feeding curculionid, Rhyssomatus marginatus Fåhraeus, was introduced into South Africa for biological control of a perennial leguminous weed, Sesbania punicea, from South America. R. marginatus has become established even though its larval food source, seeds in ripening pods, is severely depleted by another biological control agent, an apionid, Trichapion lativentre (Beguin Billecocq), which destroys nearly all the flower-buds produced by the plants and reduces seed-set by 98% on average. In spite of this indirect competition, R. marginatus destroys up to 88% of the remaining seeds that develop on S. punicea, regardless of host plant location. Detrimental intraspecific interactions between larvae of R. marginatus are minimized, and the utilization of a depleted food source is optimized, through meticulous selection of oviposition sites by the female weevils. Although numerically inferior, R. marginatus is an important supplementary agent to T. lativentre and together the two species of weevils have almost arrested the reproductive potential of S. punicea.

Sesbania punicea (Cav.) Benth., a South American leguminous shrub or small tree, has recently become a weed, principally of river banks and of wetlands, throughout South Africa. Three weevil species have been introduced for its biological control: a florivorous apionid, Trichapion lativentre (Beguin-Billecocq), that was inadvertently introduced in the 1970s, and two curculionids that were first released in 1984, a seed-feeder, Rhyssomatus marginatus Fahraeus, and a stem borer, Neodipiogrammus quadrivittatus (Olivier). The reproductive potential of S. punicea has been markedly reduced throughout South Africa by T. lativentre and, to a lesser extent, by R. marginatus. In the vicinity of release sites, many large S. punicea plants have been killed by N. quadrivittatus and the density of at least one infestation has been reduced to acceptable levels within 4 years. A critical assessment of this biocontrol programme is presented.

Sesbania punicea (Cav.) Benth. is a perennial legume that has become a weed of major importance in South Africa. Until recently, S. punicea was colonized by only one insect herbivore of any consequence, an introduced apionid weevil species, Trichapion lativentre (Beguin-Billecocq). The vegetative growth and reproductive capacity of S. punicea was shown to be significantly lower on plants at sites colonized by T. lativentre than on plants at sites without the weevils. However, these initial comparisons did not account for the extraneous effects of intersite differences, and additional analyses have been undertaken to determine the actual effects of the weevils on the weed. Regression models showed that between 77 and 83% of the variance in vegetative growth (leaflets, rachides, and stems) of S. punicea was explained by the presence of weevils, by their history of colonization, and to a lesser extent, by the density of the weevils, expressed as cumulative weevil-days. Kruskal-Wallis tests showed that the weevils also almost completely nullified the reproductive capacity of the plants by destroying nearly all of the flower buds. The results confirm that the suppression of plant growth was attributable, almost entirely, to weevil herbivory and that, in moderate to dense infestations of the weed, T. lativentre is equally effective as a biological control agent, regardless of site characteristics such as the spacing, height, or size of the trees.

A model that simulates the population dynamics of a weed, Sesbania punicea (Cav.) Benth., is described and used to examine the consequences of introducing three biological control agents. The simulated establishment of two weevil species, that primarily destroy the flower-buds and seeds respectively, indicates that satisfactory control of S. punicea is only achievable with high levels of seed reduction (99%). On its own, a stem-boring weevil causes marked fluctuations in the density of the weed before bringing it under control. A combination of all three weevil species is most effective, but ideally the stem-borer should be released some 5 years after the other two species. The role of the simulation model in evaluating actual populations of the biocontrol agents is discussed. An evaluation programme for the florivorous and seed-feeding weevils is based on predictions of how the age structure of the weed population responds to different levels of reduced seed-set. A single census of age structure conducted 4–5 years after release of the weevils will show whether S. punicea is being brought under control. These surveys preclude the need for repeated density counts of the weed before and after release of the weevils, thus facilitating an early assessment of their effectiveness and resolving the matter of whether or not additional control measures are required.

A tandem mass spectrometric procedure was developed to detect sesbanimide A and its isomers in plant materials. Analysis of seed extracts from 10 Sesbania species using this procedure readily detected sesbanimides in Drummond rattlebush, rattlebush, and bagpod ses- bania. The toxic sesbanimides were not detected in hemp sesbania or in other species with no known history of animal toxicity. Nomenclature: Sesbanimide A, 4-(5'- hydroxy - 6'-(2" - hydroxy - 3"-methyl-4" -methylene- tetrahydrofuran - 2" - yl) - 1',3' - dioxan-4' - yl)- piperidine - 2,6 - dione; Drummond rattlebush, Sesbania drummondii (Rydb.) Cory #3 SEBDR; rattlebush, Sesbania punicea (Cav.) Benth. # SEBPU; bagpod sesbania, Sesbania vesicaria (Jacq.) Ell. # SEBVI; hemp sesbania, Sesbania exaltata (Raf.) Rydb. ex A. W. Hill # SEBEX. Additional index words. Fabaceae, poisonous weed, mass spectrometry, glutarimide derivative, Sesbania drummon- dii, Sesbania vesicaria, Sesbania punicea, Sesbania exaltata, SEBDR, SEBEX, SEBPU, SEBVI.

El objetivo de esta investigación fue el estudio del crecimiento y nodulación de tres especies de Sesbania nativas de zonas inundadas en Venezuela. Las especies S. punicea (Sp) y S. sericea (Ss) fueron recolectadas en el estado Miranda y S. exasperata (Se) en el estado Aragua. Todos los individuos de cada especie recolectados en cada zona geográfica estaban nodulados en las raíces sumergidas, con los nódulos cubiertos por un aerénquima blanco. Todos los aislamientos de rizobios nativos eran de crecimiento rápido y no toleraron concentraciones de NaCl mayores al 1%. Los aislamientos de Sp acidificaron el medio de crecimiento, mientras que los de Se y Ss mostraron mayor variabilidad en la modificación del pH del medio. La mayoría de los aislamientos presentaron una alta eficiencia simbiótica en sus hospederos originales, y sólo los de Sp formaron nódulos efectivos en Vigna unguiculata. Las semillas de las tres especies germinaron después de escarificadas con ácido sulfúrico concentrado por 1h. Todas las plántulas crecidas en condiciones controladas de inundación usando soluciones nutritivas estériles sin nitrógeno alcanzaron una altura máxima de 12 cm y murieron al cabo de dos meses a pesar de estar efectivamente noduladas con sus respectivos aislamientos. En los ensayos de campo realizados en parcelas inundadas en el estado Portuguesa durante la época de lluvia, las plantas sobrepasaron el metro de altura con una eficiente nodulación. En la época de sequía, sin embargo, las plantas mostraron un menor desarrollo que se atribuyó a la reducción en el nivel del agua en las parcelas. The aim of this work was to study the growth and nodulation of three Sesbania species native of seasonally flooded areas in Venezuela. The species S. punicea (Sp) and S. sericea (Ss) were collected in the Miranda State, while S. exasperata (Se) in the Aragua State. All individuals were nodulated with nodules located in submerged roots, which were like embedded in a white aerenchyma. Rhizobial isolation from nodules yielded seven isolates from Sp, seven from Ss, and ten from Se. The bulk of isolates were fast growers and did not tolerate NaCl concentrations above 1%. All isolates from Sp were acid producers, while a greater variability was observed within isolates from Ss and Se. All isolates shown a high symbiotic efficiency in their original hosts, but only those from Sp formed effective nodules in Vigna unguiculata. Seed germination of Sesbania occurred exclusively after chemical scarification with concentrated sulfuric acid for 1 h. However, seedlings did not survive in controlled-sterile conditions in spite of the effective nodulation with their corresponding isolates. In the other hand, an optimal growth and prolific nodulation was observed in plants growing in flooded fields during the rainy season, although growth was hampered during the dry season, probably due to a marked decreases in the level of the water

El objetivo de este trabajo fue inducir la morfogénesis in vitro en cotiledones inmaduros de leguminosas forestales nativas de la República Argentina: Erythrina crista-galli L. (seibo), Acacia caven (Mol.) Mol. (espinillo), Parkinsonia aculeata L. (cina-cina), Gleditsia amorphoides (Griseb.) Taub. (espina de corona) y Sesbania punicea (Cav.) Benth. (acacia mansa). Las legumbres verdes fueron recolectadas de árboles que crecen naturalmente en los alrededores de la ciudad de La Plata (34º 55' S; 57º 57' W; 15 m snm), Provincia de Buenos Aires. Los frutos fueron desinfectados en superficie, se extrajeron las semillas inmaduras y se separaron los cotiledones del eje embrionario. Los cotiledones fueron cultivados en el medio basal Murashige-Skoog (MS), con sus macro y micronutrientes a la mitad de su concentración, suplementado con 3% de sacarosa, 0,65% de agar, 0,165 g/l de NO3NH41 ppm de 2,4-D (ácido 2,4- diclorofenoxi acético) y 0,1 ppm de Kin (cinetina). Los cultivos fueron incubados a 25 +/- 2 ºC y 16 horas de luz con una irradiancia de 60 mmol m-2 s-1. Se obtuvieron embriones somáticos en Acacia caven, regeneración de brotes y raíces adventicias en Parkinsonia aculeata, callos y raíces en Gleditsia amorphoides y callos en Erythrina crista-galli y Sesbania punicea. Los resultados sugieren que algunas leguminosas nativas de la República Argentina pueden ser propagadas mediante técnicas de cultivo de tejidos., The aim of this work was to induce the in vitro morphogenesis from inmature cotyledons of leguminous native trees from Argentina: Erythrina crista-galli L. (seibo), Acacia caven (Mol.) Mol. (espinillo), Parkinsonia aculeata L. (cina-cina), Gleditsia amorphoides (Griseb.) Taub. (espina de corona) and Sesbania punicea (Cav.) Benth. (acacia mansa). Inmature fruit were recollected from trees growing in La Plata (34º 55'S; 57º 57'W; 15 m asl), Buenos Aires. Fruit were surface sterilized and inmature seeds were removed, cotyledons were separated from the embriogenic axis. Cotyledons were stablished in Murashige-Skoog (MS) basal medium at half strength macro and micronutrients, supplemented with 3% sucrose, 0.65% agar, 0.165 g/lNH4NO3 and growth regulators (1 ppm 2,4-D (2,4-Dichlorophenoxyacetic Acid) and 0.1 ppm Kin (Kinetin)). The cultures were incubated at 25 +/- 2ºC and 16 hours of light in irradiance of 60 µmol m-2 s-1. Somatic embriogenesis was observed in Acacia caven, adventitious shoot and roots regeneration in Parkinsonia aculeata, differentiating callus and roots were induced in Gleditsia amorphoides, while in Erythrina crista-galli and Sesbania punicea only calluses were formed. Results suggest that some leguminous native from Argentine could be propagated by tissue culture techniques., Facultad de Ciencias Agrarias y Forestales

Sesbanimides are cytotoxic compounds, originally isolated in 1983 from seeds of the leguminous plants Sesbania drummondii and Sesbania punicea. In this paper we describe the bacterial production of sesbanimides by two "marine Agrobacterium"; strain PH-103 which produces Sesbanimide-A and strain PH-A034C which produces Sesbanimide-C. The isolation and taxonomy of the producing microorganisms, fermentation and isolation of sesbanimides are reported.

The establishment in South Africa of a florivorous, apionid weevil, Trichapion lativentre, on Sesbania punicea, a leguminous weed of South American origin, has reduced seed production of the plants by >98%. Surveys of the age structure and density of plants in infestations of S. punicea throughout South Africa have shown that the rate of recruitment of seedlings has drastically declined within a few years in many areas, due to the weevils. However, there has unexpectedly not been a corresponding decline in the density of mature plants in extant infestations of S. punicea. In spite of this, T. lativentre has curtailed the rate of spread of the weed into uninvaded habitats and has impeded reinvasion into areas cleared of infestations by mechanical means or by another complimentary biocontrol agent.

A technique is described for separating plant cells used for morphological studies. The plant material is placed in a concentrated solution of olive oil castile soap for 1-2 days or more. The material is then thoroughly washed and placed between two glass slides. The upper glass slide is lifted from the lower one, then gently pressed down several times. Through this procedure Malpighian cells of the seed coat of Sesbania punicea, mesophyll cells of Euphorbia peplus and of Trifolium pratense and cortical cells of the aerial roots of Monstera deliciosa have been separated. Various shapes of the Malpighian cells of the Sesbania punicea seed coat can be observed along with intermediates.

Neither of the two Sesbania species investigated bears physiologically dormant seeds. Germination depends on the seed coat becoming impermeable to water. If imbibition occurs Sesbania bispinosa will germinate at any temperature from 10 to 40 °C. Sesbania punicea on the other hand will germinate readily at temperatures from 10 to 35 °C but not at 40 °C. Both mechanical and acid scarification treatments, which render the seed coat permeable to water, resulted in germination once seeds of either species were brought into contact with moisture. Light and high oxygen concentrations had no effect on germination. During germination orange pigments were released into the incubation medium by both species. In field experiments it became apparent that seeds of S. punicea lost their impermeability quicker than did those of S. bispinosa. Seeds of S. bispinosa only emerged from a burial depth of 2 cm but not from a depth of 7 cm or more, while those of S. punicea emerged from all the depths tested up to 12 cm but not from a depth of 18 cm.

Summary The seed coat structure of Sesbania bispinosa and Sesbania punicea were investigated. Both species have seed coat structures which are typical of legume seeds. Differences do however, exist in their cuticle ornamentation, macrosclereid, and hour-glass cell layers. The macrosclereid cells of S. bispinosa are packed much tighter than those of S. punicea . This compaction may explain why the seed coats of S. bispinosa are less permeable than those of S. punicea . The integrity of the macrosclereid layer is apparently vital to seed coat impermeability. This is shown by the fact that in «rust» coloured seeds of both species, where the macrosclereid layer is interrupted by triangular cavities, the seeds were always permeable.