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Logistic curves were fitted to sigmoidal growth data obtained from tobacco (Nicotiana rustica L.) callus grown on media prepared with 0.1, 0.03, 0.01, and 0.003 m sucrose. Analysis of the growth curves indicated that final yields and specific growth rates were influenced by the initial sucrose concentration. Growth yields from the four treatments were similar (0.61 +/- 0.04 gram dry tissue per gram sucrose supplied). Initial specific growth rates exhibited a Michaelis-Menten dependency on initial sucrose concentration such that the V(max) = 0.18 g g(-1) day(-1) and Km = 0.0037 m sucrose.

A 19S particle was purified from tobacco (Nicotiana rustica) leaf cells. Its density was determined as 1296 g/cm3 in Cs2SO4-DMSO gradients, indicating the presence of RNA and protein. Polyacrylamide gel electrophoresis (PAGE) revealed eight distinct proteins in the range of 20–30 kD and RNA in the range of 70–80 nucleotides. Electron microscopic examination showed the same raspberry-shaped structure with a central depression as described for prosomes. We conclude that tobacco 19S particles represent small cytoplasmic complexes, possessing biochemical and structural characteristics similar to the hitherto known prosomes of animal cells.

The addition of exogenous nicotinic acid, nicotinamide or nicotine was studied with reference to their effects on growth and alkaloid production by hairy root cultures of Nicotiana rustica. Nicotinic acid and nicotinamide were toxic (50% phytostatic dose being 2.4 and 9 mM respectively) while nicotine was not toxic below 10 mM. Nicotinic acid (up to 5 mM) was found to be phytostatic rather than phytotoxic. Roots exposed to increasing nicotinic acid or nicotinamide levels had altered alkaloid accumulation patterns relative to the controls. The principal effects were to increase the intracellular and extracellular levels of anatabine and nicotine, with a markedly greater proportion of anatabine being produced. The use of nicotinic acid as a selection agent for the recovery of higher alkaloid-producing lines is identified and discussed.

Agrobacterium tumefaciens harboring pTiA6 incite unorganized tumors on Nicotiana rustica, sunflowers, carrots, and tomatoes, whereas isogenic strains of agrobacteria harboring pTiAg63 form "rooty" tumors on N. rustica and are essentially avirulent on sunflowers, carrots, and tomatoes. In this report we show that the different host range characteristics of these two plasmids were due, in part, to differences in the T-DNA oncogene complements of the plasmids. Specifically, we constructed derivatives of pTiAg63 that contained pTiA6 oncogenes 4, 6a, and 6b inserted into the TB-DNA region and found that agrobacteria harboring these plasmids could incite unorganized tumors on N. rustica, tomatoes, carrots, and the inbred sunflower line HA202R. Undefined host factors, however, also appeared to be involved in determining A. tumefaciens host range since three inbred sunflower lines, HA303B, HA89B, and HA290B, were susceptible to tumor formation by agrobacteria harboring pTiA6 but not by strains harboring pTiAg63 or the modified pTiAg63 plasmids.

One hundred and twelve Agrobacterium tumefaciens mutants with a deleted octopine Ti plasmid were isolated. They originated from four insertion mutants, each of which carried the transposon Tn904 at a different position in the Ti plasmid. The deletion mutants were selected on the basis of loss of the capacity encoded by the Ti plasmid to degrade octopine. They were tested for the expression of other Ti-plasmid coded functions: tumor induction, presence of lysopine dehydrogenase activity in the tumor, and exclusion of phage Ap-1. For 21 mutants affected in at least one of these functions, the map position of the deletions was determined. It was found that deletions at two separated loci give rise to an Occ− phenotype. Genes for Ap-1 exclusion were mapped on a small region just outside and to the right of the TL + TR region. Most of the TR region, present as TR-DNA in a limited number of crown gall tissues only, was shown to be unnecessary for tumor formation, since it could be deleted without affecting virulence (tested on various plant species) of the mutants. However, if the TR region together with a small part of the adjacent TL region, which is always present as TL-DNA in normal crown gall tissues, was deleted the mutants became weakly virulent on Kalanchoe and Nicotiana rustica and avirulent on tomato. We hypothesize that in this case a region necessary for T-DNA integration has been deleted. The same region was found to be essential for lysopine dehydrogenase activity in the tumors.

Tobacco streak virus (TSV) was isolated from a plant of sunflower (Helianthus annuus) showing severe necrosis and chlorosis in the leaves. The virus was identified as TSV by serology and, to some extent, by host range. The type of symptoms varied with the host plant in which the virus had been propagated in successive transfers. Test plants inoculated with the virus propagated inNicotiana rustica produced symptoms which very much differed from those brought about by the virus from eitherN. clevelandii orChenopodium amaranticolor.

In the sexual interspecific cross, Nicotiana rustica L.xN. tabacum L., N. rustica can serve as the female but not as the male parent. By fusion of protoplasts, the barrier to fertilization was overcome and somatic hybrids containing N. tabacum cytoplasm were produced as shown by isoelectric focusing of the Fraction-1 protein (F-1-protein). All somatic hybrids displayed polypeptides of the large subunit of F-1 protein (which is coded by the chloroplast genome) characteristic of only one or the other parental species. Two hybrids had large subunits of the N. tabacum type and two hybrids had those of the N. rustica type. Three hybrids contained three smallsubunit polypeptides (coded by the nuclear genome), one being characteristic of N. rustica, one characteristic of N. tabacum, and one with an isoelectric point common to both species. A fourth hybrid contained only two small-subunit polypeptides of the N. tabacum type but in a F-1 protein macromolecule whose large subunits were of the N. rustica type. One somatic hybrid was self-fertile and its F2 progeny contained large- and small-subunit polypeptides indistinguishable in their isoelectric points from those in the parent F1 hybrid. All somatic hybrids showed an aneuploid chromosome number and morphological characteristics intermediate between those of N. rustica and N. tabacum.

Somatic hybrid plants, produced between Nicotiana rustica and N. tabacum by heterokaryon isolation and culture and also by mutant complementation, were examined regarding their ability to set seed. From a total of seventeen independent somatic hybrids, three were found to be partially self-fertile while the others did not set seed. Differences regarding the methods of hybrid selection, parental varieties and chloroplast composition of hybrids did not appear to be significant regarding the ability of plants to set seed. Much variation in fertility was observed in subsequent generations and by recurrent selection of the most fertile, over two generations, it was possible to increase the level of self-fertility in some of the progeny. One R2 derivative possessed approximately a tenfold higher level of self-fertility than it's somatic hybrid parent. The presence of genetic markers from both parents were observed in all progeny indicating their hybrid nature.

THE phenotypes of some inbred lines of Linum usitatissimum (flax) and Nicotiana rustica can be altered environmentally by fertiliser treatments, and the fertiliser-induced phenotypes show stable inheritance independent of the inducing conditions1–3. In flax, the stably inherited large (L) and small (S) phenotypes can be induced from the plastic (Pl) genotype Stormont Cirrus by one generation of growth with high nitrogen or phosphorus fertiliser treatments respectively. The induced phenotypes of L and S, differing for example in plant weight and degree of branching, behave in most respects as distinct genotypes and have been termed genotrophs.

When Nicotiana glutinosa leaves, immediately after inoculation with tobacco mosaic virus (TMV) were floated on 0.1–20 mg/l of kinetin (K), kinetin riboside (KR), N 6 -benzyladenine (BAD), N 6 -benzylaminopurine (BAP), or N 6 -isopentenyladenosine (IPA), lesion formation was inhibited but virus production was stimulated. In Phaseolus vulgaris L. var. Pinto (another local-lesion host), however, K, KR, and IPA severely, and BAP or BAD to a lesser extent, inhibited lesion formation and virus production. In addition, BAD caused a substantial increase in lesion size whereas IPA and BAP reduced the lesion size. When TMV-inoculated leaves of Nicotiana tabacum L. var. Wisconsin 38 and of Nicotiana rustica (two systemic hosts) were treated with the cytokinins, virus production was stimulated with all cytokinins except KR, which inhibited virus production in N. rustica . No consistent effect of cytokinins on chlorophyll retention in healthy or virus-infected leaves from the plants was noted. These results show that the effect of cytokinins on viruses appears to be very specific and may depend on particular host, virus system, cytokinin and its concentration, and other factors.

Results from inoculation of two vector-specialized forms of potato yellow dwarf virus (PYDV) on cell monolayers derived from their vectors and related nonvectors indicate that the effect of pH on inoculation is mediated through the virus, not through the host. The optimum pH for sanguinolenta yellow dwarf virus (SYDV) inoculation on cell monolayers is near 5.9; the optimum pH for inoculation of constricta yellow dwarf virus (CYDV) on cell monolayers is near 5.3. Forty-five minutes is sufficient for inoculation of PYDV on leafhopper cell monolayers. A pH of 7.0 is better than 6.5 or 7.5 for inoculating leaves of Nicotiana rustica with SYDV. Use of histidine-MgCl2 (His-MgCl2) solution for inoculation of SYDV on N. rustica gave better results than did phosphate buffer at the same pH. In His-MgCl2 buffer SYDV is most stable near pH 6.4 at 0° and pH 6.5 at 30°; CYDV is most stable near pH 6.9 at 0° and pH 5.9 at 30°. Near the optimal pH for inoculation of cell monolayers with SYDV at 30°, namely pH 5.9, the half-life of the virus in the His-MgCl2 solution is 21.4 min. The corresponding half-life for CYDV near its optimal pH for inoculation, namely 5.3, is 7.7 min. Both SYDV and CYDV reached peak concentrations in N. rustica about 10 days after the appearance of the first systemic symptom. After reaching such a peak about 30% of the infectious SYDV was lost by day 12, but thereafter the concentration remained almost constant up to day 24. Similarly, about 70% of peak CYDV infectivity was lost by day 12, and more than 80% by day 14 and day 16. Purified sterile infectious inocula were obtained by harvesting infected N. rustica plant tissue at the time of peak virus concentration. SYDV can be stored at −80° for as long as 3 years without appreciable loss of infectivity. CYDV, similarly prepared and stored, seriously deteriorated in infectivity between 6 and 12 months after storage.

Three isolates of aster yellows virus, collected in California, were differentiated on the basis of symptoms on common plantain, Plantago major L., Nicotiana rustica L. var. humilis, aster,1 and periwinkle and were designated as the Severe, Dwarf, and Tulelake strains. Leafhopper transmission tests conducted on 20 species of plants indicated only minor host range differences between the three strains. Cross protection experiments on plantain and N. rustica provided evidence that plants infected with either Dwarf or Severe strains were protected from infection by Tulelake strain. Protection was reciprocal between the Dwarf and Severe strains. In contrast, in plantain plants infected with Tulelake strain and challenged by the Dwarf or Severe strain the original strain was replaced and symptoms of the challenging strain developed. The most unexpected results were obtained when N. rustica plants infected with Tulelake strain were challenged with either Dwarf or Severe strain. This antagonistic interaction resulted in mutual suppression of both the Tulelake and challenging strain in each combination and the development of symptomless plants. Leafhoppers acquired virus from 14 of 23 such plants. The Tulelake strain was recovered from 7 plants, and both the Tulelake strain and the challenging strain were acquired from the seven other plants.

During the early period of the twentieth century, it was generally thought that alkaloids were byproducts of a number of irreversible and physiologically useless reactions associated with nitrogen metabolism (1-3). This idea was gradually discarded as an increasing number of experiments showed that alkaloids are metabolically active. Indirect evidence for the decomposition of ricinine (II, fig 1) in the living plant was obtained by several investigators in nonisotopic experiments. Weevers (4) showed that the ricinine content decreased with increasing age of castor plants grown on nitrogen-depleted soil. Bogdashevskaya (5) showed that the content of ricinine was reduced in leaves which were shaded from the light, while the upper unshaded leaves of such plants produced supernormal levels of ricinine. Waller and Nakazawa (6) reported that ricinine was rapidly utilized by castor cotyledons in the dlark; however, the amount of ricinine did not decrease when nicotinic acid was present in the medium. A preliminary report (7) has been made on the degradation of ricinine in a cell-free system of young castor plants. Tso and Jeffrey (8) were the first to use isotopic tracers to demonstrate that alkaloids are metabolically active. They fed nitrogen-15 labeled nicotine (III, fig 1), nornicotine and anabasine (IV, fig 1) to tobacco plants ancd found that a major portion of the alkaloids supplied was broken down. Griffith et al. (9) indicated that nicotinic acid (I) was a metabolite of nicotine. Griffith and Griffith (10) showed that transmethylation of methionine to nicotine and catabolism of the ring structures of nicotine occurs almost exclusively in root tissue of Nicotiana rustica. It is well known that nicotinic acid (I, fig 1) can serve as a precursor of each of these alkaloids [fig 1; see Leete (11) for a recent review]". The experiments described herein were performed to determine if ricinine could be degraded by the castor plant and to observe the turnover of ricinine in different organs.

WHEN meristem tips of the orchid, Cymbidium, are cultured, they do not give rise to one plant, but usually produce a mass of protocorms, each capable of developing into a plant1. Growth of meristems in shake culture increases the rate of multiplication of the protocorms2,3.

Electron microscopy of tissues of Nicotiana rustica and Trifolium incarnatum infected with potato yellow dwarf virus indicated that the virus particles were bacilliform with average dimensions of 380 mμ by 75 mμ. A striking association of virus particles with the nuclei of infected cells was apparent from sections which showed numerous virus particles at the nuclear periphery and in what appeared to be intranuclear virus inclusions. Careful examination of these apparent inclusions revealed the presence of the nuclear envelope surrounding them in addition to cytoplasmic organelles within them. Such profiles were interpreted as having arisen when the sections passed through invaginations of the cytoplasm into the nucleus. In all the sections showing virus particles associated with the nucleus, large numbers of virus particles were found to be present in expanded areas between the two lamellae of the nuclear envelope. This location is suggested as a possible site of virus assembly. Several micrographs of particles found in this location suggested incorporation of the inner lamella of the nuclear envelope into the viral envelope. The viral envelope was seen to be composed of three lamellae, approximately 35 A in thickness and spaced about 50 A apart. The individual lamellae had the appearance of being constructed of laterally united subunits, about 35 A in diameter. Various micrographs indicated a possible helical arrangement of certain components present in the virus core. The significance of these findings in elucidating relationships between potato yellow dwarf virus and some other plant and animal viruses is discussed.

Radioactive nicotine was synthesized by Nicotiana rustica L. which was fed sodium acetate-1-C(14), sodium acetate-2-C(14), sodium pyruvate-1-C(14), or sodium pyruvate-3-C(14). Acetate-2-C(14) and pyruvate-3-C(14) were converted to nicotine with the least dilution of radioisotope, whereas pyruvate-1-C(14) was incorporated with a relatively large dilution. When acetate-1-C(14) was administered to the plants the nicotine contained C(14) only in the pyrrolidine ring. After acetate-2-C(14) was fed, C(14) was located in both the pyrrolidine and pyridine rings.

A study was made of the effect of gibberellic acid on the growth of tobacco plants and the accumulation of nicotine. While gibberellic acid increased the rate of growth and the total chlorophyll content, a decrease in nicotine content was observed.

Nicotiana rustica, spec. nov. 2. Nicotiana foliis ovatis. Hort. cliff. 56. Hort. ups. 45. Roy. lugdb. 423. Nicotiana minor. Bauh. pin. 170. Pachyphylla. Reneal. spec. 40. Habitat in America , nunc in Europa. ���, Published as part of Linnaeus, Carolus, 1753, Species plantarum: exhibentes plantas rite cognitas, ad genera relatas, cum differentiis specificis, nominibus trivialibus, synonymis selectis, locis natalibus, secundum systema sexuale digestas, Stockholm :Laurentius Salvius on page 180, DOI: 10.5281/zenodo.3931989

Partly dehydrated tobacco leaf tissue (Nicotiana rustica), stripped of the lower epidermis, was used to study the effect of kinetin on the rate of rehydration. Depending on the rate of rehydration in untreated tissue, kinetin either increased or decreased rehydration rates. The response to kinetin was very rapid and could be discerned in less than 2 minutes. On extensive dehydration, the tissue lost the capacity to respond to kinetin. Salinity stress, which decreases the endogenous level of cytokinins in the plant, conditions the leaf to stimulation of rehydration by kinetin.It is suggested that cytokinins may play a role in controlling water permeability of the leaf tissue.

In order to investigate whether Myzus persicae (Sulz.) takes up tobacco mosaic virus, droplets emerging from stylets cut while aphids were feeding, were tested for the virus by (1) inoculation of Nicotiana rustica and N. tabacum var. White Burley, (2) examination under the electron microscope, and (3) a microserological method. All gave negative results. Consequently the authors are of the opinion that M. persicae does not imbibe tobacco mosaic virus from tobacco.

International audience; Mature (flowering) tobacco (Nicotiana tabacum cv. PBD6, Nicotiana rustica cv. Brasilia) and maize (Zea mays cv. INRA 260) plants were grown in an acid sandy-clay soil, enriched to 5.4 mg Cd kg–1 dry weight soil with cadmium nitrate. The plants were grown in containers in the open air. No visible symptoms of Cd toxicity developed on plant shoots over the 2-month growing period. Dry-matter yields showed that while the Nicotiana spp. were unaffected by the Cd application the yield of Z. mays decreased by 21%. Cd accumulation and distribution in leaves, stems and roots were examined. In the control treatment (0.44 mg Cd kg–1 dry weight soil), plant Cd levels ranged from 0.4 to 6.8 mg kg–1 dry weight depending on plant species and plant parts. Soil Cd enrichment invariably increased the Cd concentrations in plant parts, which varied from 10.1 to 164 mg kg–1 dry weight. The maximum Cd concentrations occurred in the leaves of N. tabacum. In N. rustica 75% of the total Cd taken up by the plant was transported to the leaves, and 81% for N. tabacum irrespective of the Cd level in the soil. In contrast, the Cd concentrations in maize roots were almost five times higher than those in the leaves. More than 50% of the total Cd taken up by maize was retained in the roots at both soil Cd levels. The Cd level in N. tabacum leaves was 1.5 and 2 times higher at the low and high Cd soil level, respectively, than that in N. rustica leaves, but no significant difference was found in root Cd concentrations between the two Nicotiana spp. Cd bioavailability was calculated as the ratio of the Cd level in the control plants to that in the soil or as the ratio of the additional Cd taken up from cadmium nitrate to the amount of Cd applied. The results showed that the plant species used can be ranked in a decreasing order as follows: N. tabacum > N. rustica > Z. mays.

Tobacco (Nicotiana rustica) plants were stressed by addition of polyethylene glycol solution (-20 bar) to the growth medium. The proline contents and concentrations in total protoplasts, vacuoles, and extravacuolar fractions of these plants have been determined and compared with protoplasts and cell fractions of well-watered plants. As compared to the control, the stress treatment of intact plants results in a 7-fold increase of the proline content in the extravacuolar fraction while the vacuolar content was enriched only 2.6-fold. In protoplasts of control plants, a proline concentration ratio (extravacuole to vacuole) of 1 was measured. In protoplasts of stressed plants, this ratio was nearly 3. Thus, water stress seems to have an effect on a tonoplast-localized transport system for proline.

Quinolinic acid-2,3,7,8-14C, nicotinic acid-2,3,7-14C, and nicotinamide adenine dinucleotide-2,3,7-14C were shown to be incorporated into nicotine by Nicotiana rustica L. with very similar efficiencies. It is postulated that compounds of the pyridine nucleotide cycle, previously implicated as a source of metabolic intermediates for the biosynthesis of ricinine in Ricinus communis L., could serve the same function in nicotine biosynthesis in the tobacco plant.

WHEN THE SPANISH first arrived in Central and South America following Columbus' initial voyages, they found that every newly discovered area whose inhabitants used tobacco had its own name for the plant. Not all the aborigines used tobacco, by any means. The Chilean Indians, for example, did not smoke until the Spanish introduced the custom to them; neither did the Incas of Peru. Bolivian Indians smoke very little to the present day, preferring to chew the coca leaf, which is also probably their most widely-used medicine, even to being an alleged aphrodisiac.1 But generally, the Indians around the Caribbean basin, the Gulf of Mexico, and down the eastern coast smoked heavily, using all five forms of tobacco consumption-pipes, snuff, chewing, cigars, and corn-husk cigarettes-and they also had considerably different names for the plant. Some of the Mexican Indians called it picietl or yetl. Brazilian coastal Indians called it petun or petum or patoun; and among the Portuguese the expression "making a petun" arose, meaning "making a cigar." Curiously, the word later developed into petunia, a name for a well-known plant within the same botanical family, which suggests that the Indians smoked petunias as well. The Haitians, on the other hand, called tobacco kohaba or cohoba (which possibly has an etymological connection with tobacco), although there is some disagreement about what kohaba really meant: Compton Mackenzie thinks it meant snuffing, not tobacco.2 Later reports showed a similar confusion in North America: the Virginian natives called tobacco uppowoc, while those in Massachusetts referred to it as pooke.3 Even in comparatively modern times the different North American Indian tribes have had dissimilar names for tobacco. As recently as I890 James Mooney reported that the Cherokees called tobacco Tsala. He added that they made this a kind of generic name for a number of plants having similar manners of seeding, but that these plants all shared the name Tsaliyusti ("like tobacco" ) . One of these was the common mullein, which various informants called the blue, yellow, downy, and large Tsaliyust.4 Another North American name for tobacco was o-yen'-kwa, which the Onondagas used generally for tobacco as late as I902, adding the name hon'we, "real" or "original," to distinguish their own kind, Nicotiana rustica. The distinction is an interesting one. Although there are about sixty species of tobacco, the Indians

Three tobacco cultivars (Nicotiana tabacum) and two Nicotiana species, used for virus identification studies, were tested for susceptibility to air pollutants. The air pollutants used were (i) ozone; (ii) sulfur dioxide; and (iii) a mixture of both gases. Nicotiana rustica var. brasilia was the most susceptible cultivar to injury from individual gases, a gas mixture, and ambient polluted air. Nicotiana rustica var. brasilia displayed from 25 to 70% leaf injury when exposed to increasing ozone doses (10 to 30 pphm). Ozone injury to N. glutinosa fumigated at the same doses ranged from 10 to 60%. Samsun, Samsun (NN), and Xanthi cultivars were more resistant to ozone than N. rustica var. brasilia or N. glutinosa. Sulfur dioxide (ca. 45 pphm) added to an ozone (ca. 3.0 pphm) atmosphere induced a synergistic response evidenced as injury to all cultivars and species. Mixed gas injury was more acute on N. glutinosa and N. rustica var. brasilia than on Samsun, Samsun (NN), and Xanthi. Samsun and Samsun (NN) were more susceptible to sulfur dioxide (125 pphm) than N. glutinosa and Xanthi. Fumigations produced two injury syndromes: (i) light or dark punctate flecks, on upper leaf surfaces; or (ii) bifacial tissue collapse.