The effect of root temperature on growth of curled parsley

Summary Curled parsley was grown at root-zone temperature (RZT) of 18, 21, 24, 27 and 36°C at air temperature (AT) of 18 and 21°C. Maximum growth was obtained at 18°C AT and 24°C RZT, but there were no significant differences between 18 and 27°C RZT. Shoot and root growth were severely inhibited at 36°C constant RZT. The growth was also retarded when RZT rose to 36°C for 30 minutes per day, even when compared to a RZT of constant 27°C. This indicates that a short exposure to RZT above 30°C retards growth. A relatively low daily average RZT did not compensate for the damage caused by a short daily high temperature exposure. Optimum temperature for curled parsley seems to be about 21°C. Report No. 316.     

Characterization of two partially purified xyloglucan endotransglycosylases from parsley (<Emphasis Type="Italic">Petroselinum crispum</Emphasis>) roots

Two forms of xyloglucan endotransglycosylase differing in isoelectric points were isolated from the protein mixture obtained from parsley roots and partially characterized. Both forms were glycoproteins differing in their specific activities but other features were almost the same. Activity and stability of both enzymes in broad pH region were observed with two pH optima, one at acidic pH (5.8) and the second one at basic pH (8.8). The enzymes behaved as typical transglycosylases since no activity was observed in the absence of xyloglucan oligosaccharides in the viscometric assay. Small hetero-transglycosylating activities were observed when hydroxyethyl-or carboxymethyl-celluloses instead of xyloglucan as donor substrate were used as well as when cello-oligosaccharides instead of xyloglucan oligosaccharides were used as the acceptor substrate.     

Metabolism of aflatoxin B1 by Petroselinum crispum (parsley)

On administration of aflatoxin B₁ to whole parsley (Petroselinum crispum) plants, a derivative was formed, which was shown to be aflatoxicol by its chromatographic properties and mass spectrometry. Optimum conditions for the production of the derivative was on the second day after administration of the toxin to the plants, which were 90 days old after germination. Cell-free preparations of parsley were found not to produce aflatoxicol A from added aflatoxin B₁; instead they formed two new derivatives, which from chromatographic properties, were shown to be more polar than either aflatoxin B₁ or aflatoxicol A.     

Micropropagation of Paulownia fortuneii through in vitro axillary shoot proliferation

Primary cultures were established with nodal segments from juvenile shoots of two- year-old Paulownia fortuneii trees from a clonal plantation in Andhra Pradesh. A medium containing half-strength MS salts + RAP (1 mg/L) + sucrose (2%) produced optimum bud break in nodal explants. The same basal medium with reduced hormone level (0.5 mg/L) supported maximum multiplication of secondary cultures of P. fortuneii (1:6 in 6 weeks). Specific treatments were tested to enhance this rate of multiplication. In one approach, five to six week old in vitro grown shoots were ratooned (cutting the main shoot at the bottom leaving one node). The stumps (ratooned basal node) produced 2 to 3 axillary shoots, which grew into 4 to 5 nodes by 3 weeks; thus, providing additional shoots from the same explant. This provided 30% additional shoots in 4 cycles. Secondly, reducing the light intensity to 1200 lux resulted in higher shoot elongation, i.e, formation of 8 nodes in 5 weeks with healthier shoots than the normal intensity of 3000 lux under which only 6 nodes were produced in 6 weeks. In vitro-grown shoots could be successfully rooted ex vitro in vermiculite + cocopeat mixture (1:1 v/v) under 90% humidity, transferred to soil in polybags for hardening in the green house for 2 weeks and shifted to shade net for further hardening. After one month, the plants could be successfully transplanted to field with 95% survival. Micropropagated plants showed an excellent growth in the field attaining a height of 1.5 m and a collar diameter of 2.8 cm in 3 months.     

Two alleles of the single-copy chalcone synthase gene in parsley differ by a transposon-like element

We have analysed three nearly full-length cDNAs complementary to mRNAs encoding two PR1 (pathogenesis-related, class 1) proteins in parsley (Petroselinum crispum). Furthermore, one selected genomic clone containing the PcPR1-1 gene was investigated in detail. The structural organization and possible regulatory elements in the 5' flanking region of this gene are presented. In situ RNA hybridization in fungus-infected parsley leaf tissue demonstrated rapid and massive PR1 mRNA accumulation around infection sites.     

Micropropagation of Camptotheca acuminata decaisne from axillary buds, shoot tips, and seed embryos in a tissue culture system

Summary Micropropagation of the anti-cancer plant Camptotheca acuminata Decaisne from axillary buds and seed embryos was investigated. Axillary buds from greenhouse seedlings required a period of culture in media free of N⁶-benzyladenine (BA) before multiple shoot induction began. Direct induction of multiple shoots on BA-containing medium resulted in high mortality of the axillary buds. Multiple shoot induction from the greenhouse axillary buds was best achieved on B5 with 4.4 μM BA+0.5μM α-naphthaleneacetic acid, forming an average of three 2-mm tall shoots per bud in 8 wk. Elongation of these multiple shoots was successful at a lower BA level (0.22 μM) on B5 medium. Both in vitro and ex vitro rooting of the microcuttings was feasible with indole-3-butyric acid in the culture media, but ex vitro rooting led to high plantlet survival. Seed embryos were not ideal explants for multiple shoot induction. Shoot tips and axillary buds of in vitro-germinated seedlings showed an optimal multiple shoot formation on B5 with 8.9 μM BA, double the optimal BA level for greenhouse axillary buds. Using axillary buds to propagate C. acuminata plants in vitro is feasible for mass propagation of desired clonal lines high in camptothecin concentrations.     

Micropropagation of kiwifruit using non-axenic shoot tips

Kiwifruit (Actinidia chinensis Planch.) shoot tips were subjected to a standard surface sterilization procedure and cultured on a Murashige and Skoog basal medium in the presence of two surviving bacterial contaminants. The fresh weight increase of the cultures and the number of shoots produced were greater in liquid medium than in medium solidified with 0.4 or 0.8% agar. A greater number of shoots was obtained with 125 ml than with 50, 250, or 500 ml Erlenmeyer flasks. A concentration of 2 mgl^-1 N⁶-benzylaminopurine (BAP) gave a greater increase in fresh weight than either 0 or 4 mgl^-1.Shoots cut from proliferating cultures were dipped in 0.05% indolebutyric acid (IBA) and rooted directly in a peat: vermiculite: perlite mix. Over 93 % of 907 plantlets produced were successfully acclimatized. The productivity of the method was comparable to that reported for the axenic culture of meristems. The contaminants which survived the initial surface sterilization procedure thus presented no major obstacle to the in vitro propagation of kiwifruit.     

Micropropagation of Laburnum anagyroides Medic. through axillary shoot regeneration

An in vitro propagation system based on the proliferation of axillary buds has been developed for Laburnum anagyroides. Culture initiation was influenced by explanting season, with the maximum response obtained from explants harvested in spring and autumn while the lowest response was noted in summer explants. The best shoot induction was observed on Murashige and Skoog medium (MS) supplemented with 2.22 μM 6-benzylaminopurine (BAP). The basal media, type of cytokinin, and explant type were the most important factors affecting shoot multiplication of L. anagyroides. Medium comprised of ½MS salts was found to be more efficient for axillary shoot multiplication compared to full-strength MS or Wood Plant Medium (WPM) when using identical growth regulators. Shoot tip explants were more responsive than nodal segments of microshoots for micropropagation. In vitro-derived shoots, >10 mm in length, were successfully rooted in medium containing ¼MS salts and 2.68 μM α-naphtalene acetic acid (NAA). In vitro-regenerated plantlets were adapted to ex vitro conditions and transferred to a greenhouse. This is the first report for successful in vitro propagation of L. anagyroides from bud explants of mature trees.     

Micropropagation of black pepper (Piper nigrum Linn.) through shoot tip cultures

Summary The morphogenetic potential of shoot tip explants of black pepper (Piper nigrum) was investigated and an effective multiple-shoot propagation method is described. Various combinations of media, growth regulators and sterilization treatments were compared. Problems with establishment in tissue culture sometimes occurred, probably caused by endogenous pathogens associated with tissue exudates. The best establishment and proliferation of shoot tip explants was obtained on MS medium containing 1.5 mg l^–1 BAP alone; subsequent growth and development of lateral branches was best on media containing 1.5 mg l^–1 BAP plus 3.0 mg l^–1 IBA. Adenine sulphate inhibited the number of explants showing regeneration but increased the number of shoot buds per regenerating explant. Shoots were rooted on a 50% strength medium containing 1mg l^–1 NAA.Abbreviations AdSO₄ adenine hemisulphate - BAP 6-benzylaminopurine - IBA indole-3-butyric acid - NAA napthaleneacetic acid     

In vitro axillary shoot proliferation of apple rootstocks under different ethylene conditions

Summary Ethylene effect on in vitro shoot proliferation of two apple rootstocks, MM111 and M9, was studied. Ethylene biosynthesis was proportionally stimulated by increasing concentrations of the precursor 1-aminocyclopropane-1-carboxylic acid (ACC). When 25 μM or more ACC was applied without any control of the headspace of culture vessels, shoot proliferation of both rootstocks was negatively affected. However, when shoot cultures were transferred to ACC-supplemented medium after the second week of culture, ACC had no effect. Supplementing the medium with aminoethoxyvinylglycine (AVG), an inhibitor of ethylene biosynthesis, together with the application of gas traps inside the flasks, significantly enhanced axillary shoot formation and elongation. Steady and high exogenous concentrations of ethylene in the culture flasks had negative effects on shoot proliferation. MM111 appeared to be more sensitive to ethylene than M9. For AVG a threshold dose was noticed, beyond which phytotoxic effects were induced.     

Optimizing the shoot proliferation protocol of Penthorum chinense by axillary buds

Four parameters, three hormones and sucrose, at seven concentrations, were designed for shoot proliferation of Penthorum chinense by uniform design. The obtained data were used for building two quadratic polynomial equations by partial least square to determine optimum concentrations of four factors. Experiments for verification confirmed that no significant difference existed between the predicted and the validated values in shoot number and length based on all inoculated explants.     

Rapid multiplication of Dalbergia sissoo Roxb.: a timber yielding tree legume through axillary shoot proliferation and ex vitro rooting

An efficient and improved method for in vitro propagation of mature tree of Dalbergia sissoo, an ecologically and commercially important timber yielding species, has been developed through axillary shoot proliferation. Bud breaking occurred from nodal shoot segments derived from rejuvenated shoots produced during early spring from a 20–25-year-old lopped tree, on MS medium containing 8.88 μM benzylaminopurine (BAP). Multiple shoots differentiated (20–21shoots/node) on re-culture of explants on half-strength agar gelled amended MS medium with a combination of 2.22 μM of BAP and 0.002 μM of thidiazuron (TDZ) with 1.0 mM each of Ca(NO₃)₂, K₂SO₄, KCl, and NH₄(SO₄)₂. The maximum shoot multiplication (29–30 shoots/node) was achieved on subculturing in the above mentioned but liquid medium. Furthermore, the problem of shoot tip necrosis and defoliation observed on solid medium were overcome by the use of liquid medium. Ex vitro rooting was achieved on soilrite after basal treatment of microshoots with 984 μM of indole-3-butyric acid (IBA) for 2 min. About 90 % microshoots were rooted on soilrite within 2–3 weeks under the greenhouse conditions. From 20 nodal shoot segments, about 435 hardened plants were acclimatized and transplanted. This is the first report for rapid in vitro propagation of mature trees of D. sissoo on liquid medium followed by ex vitro rooting.     

Micropropagation of Actinidia kolomikta

Nodal segments of female A. kolomikta shoots were cultured on Murashige and Skoog modified medium with different growth regulator concentrations. The highest multiplication rate (9.5) was achieved on a medium with 10 M benzyladenine and 0.1 M indolebutyric acid. Over 90% of shoots rooted in vivo after pulse stimulation with indolebutyric acid.Abbreviations BA benzyladenine - IBA indole-3-butyric acid - NAA 1-naphthaleneacetic acid     

抗风桐的丛生芽诱导与再生

南海珊瑚岛礁自然植被由于人类干扰和环境变化出现了退化现象,急需进行植被恢复重建。抗风桐作为南海珊瑚岛礁的优势种,在防风固沙以及植被生态恢复等方面发挥着重要作用。该文以抗风桐带腋芽茎段为外植体,研究不同基本培养基、激素对其不定芽增殖和活性炭对生根、移栽的影响,以便建立其种苗快速繁殖和植株再生体系。结果表明:(1) MS基本培养基适合于丛生芽的诱导和增殖,最佳继代培养周期为60 d,最佳的不定芽增殖培养基为MS+2.0 mg·L~(-1)6-BA+0.1 mg·L~(-1)NAA,培养60 d后增殖倍数达5.52;(2)不定芽在MS+1.0 mg·L~(-1)IBA培养基中生根率为96.0%,在生根培养基中添加1.6 g·L~(-1)活性炭后其生根率下降至42.4%;(3)以添加活性炭生根培养获得的组培苗进行移栽成活率高达93.9%,而不添加活性炭生根培养的组培苗移栽成活率仅为78.3%。研究结果可为抗风桐种苗的离体快繁和珊瑚岛礁的植被恢复奠定技术基础。     

Phospholipase A2 in auxin and elicitor signal transduction in cultured parsley cells (Petroselinum crispum L.)

Signal-activated phospholipase A₂ cleavesphosphatidylcholine (PC) into free fatty acids and LPC, respectively.Using bis-BODIPY-PC as an indicator substrate for phospholipaseA₂ which is taken up by parsley cells, active auxins atconcentrations as low as 1 M and a fungal elicitor induced fattyacid-accumulation. Nordihydroguajaretic acid inhibited the accumulationof fatty acid induced by the elicitor. In addition to this, theelicitor, but not auxin, decreased the pool size of diacylglycerol,which seemed to originate from a PC-splitting phospholipase C, whichwould be a new enzyme in plant signal transduction. However, thiselicitor is known to rapidly increase cytosolic calcium in parsley cellsand this activates phospholipase C. Thus, activation of phospholipase Cshould lead to an increase of diacylglycerol and not to a decrease whichmight indicate a discrepancy between animal and plant phospholipidsignal transduction.     

Micropropagation of <Emphasis Type="Italic">Penthorum chinense</Emphasis> through axillary bud

This study reports a protocol for successful micropropagation of Penthorum chinense using nodal explants on Murashige and Skoog (MS) medium supplemented with 6-benzyladenine (BA) or kinetin (Kn). The presence of BA promoted a higher rate of shoot multiplication than Kn. Maximum multiple shoot formation was observed in 59.2% of nodal explants cultured on MS medium supplemented with 2.0 mg l⁻¹ BA after 6 wk. After subculture for 4 wk, the maximum number of shoots (6.4) was obtained on a medium with 2.0 mg l⁻¹ BA, but shoots were too short and not suitable for micropropagation. The taller shoots that regenerated in the presence of lower BA concentration (1.0 mg l⁻¹) were selected for root induction study. Most shoots (98.8%) rooted in the presence of 0.5 mg l⁻¹ indole-3-acetic acid after 3 wk, with each shoot forming an average of 10.0 roots. Plantlets were transferred to soil and successfully acclimatized.     

Micropropagation of Vitex negundo L., a woody aromatic medicinal shrub, through high-frequency axillary shoot proliferation

A protocol is described for rapid and large-scale propagation of the woody aromatic and medicinal shrub Vitex negundo by in vitro culture of nodal segments from mature plants. Of the three different cytokinins – N⁶-benzyladenine (BA), kinetin, and thidiazuron – evaluated as supplements to Murashige and Skoog (MS) medium, BA at an optimal concentration of 2.0 mg/l was most effective in inducing bud break. Although callus-free multiple-shoot formation was a function of cytokinin activity alone, faster bud break coupled with an enhanced frequency of shoot development (92%) and internode elongation were dependent on the synergistic influence of gibberellic acid (GA₃) when used at an optimal concentration (0.4 mg/l) along with BA (2.0 mg/l). The frequency of shoot proliferation was markedly influenced by the explanting season. By repeated subculturing of nodal segments harvested from the in vitro-formed axenic shoots on MS containing 1.0 mg/l BA and 0.4 mg/l GA₃, prolific shoot cultures free from proximal callusing and showing a high-frequency multiplication rate were established. The percentage shoot multiplication (98–100%) as well as the number of shoots per node (six to eight) were highest during the first three culture passages, after which there was a gradual decline in shoot development. Rooting was best induced (94%) in shoots excised from proliferated shoot cultures on half-strength MS medium augmented with an optimal combination of indole-3-acetic acid and indole-3-butyric acid each at 1.0 mg/l. Vermi-compost was the most suitable planting substrate for hardening inside a plant growth chamber and its use ensured high-frequency survival (93%) of regenerated plants prior to outdoor transfer. Micropropagated plants established in garden soil were uniform and identical to the donor plant with respect to growth characteristics as well as vegetative and floral morphology. Received: 10 January 1998 / Revision received: 17 June 1998 / Accepted: 8 July 1998     

Micropropagation of licorice (Glycyrrhiza glabra L.) through shoot tip and nodal cultures

Summary Apical and axillary buds ofGlycyrrhiza glabra commonly known as licorice, a plant of repute in the Indian system of medicine, were used for induction of adventitious shoots. For induction of multiple shoots, Murashige and Skoog’s (MS) medium with N⁶-benzyladenine (BA, 0.88–8.87 μM) was used. Reduction in major salts of MS medium enhanced the multiplication ratio up to 1∶10. Plants transferred to the greenhouse showed 90% survival. The present work describes a stepwise protocol for production ofGlycyrrhiza glabra plants on simple minimal media, where very high multiplication rates with healthy root systems were obtained. Roots being the organ of commercial importance, the protocol has tremendous potential.     

Micropropagation ofPrunus mume

Shoot proliferation from axillary buds ofPrunus mume Sieb. et Zucc. was obtained on Woody Plant Medium (WPM) supplemented with 1 to 5 M benzyladenine, 3% sorbitol and solidified with 0.5 to 0.7% agar. Effects of different carbon sources on shoot proliferation were examined. Glucose provided better shoot proliferation than sucrose, sorbitol and fructose. In the presence of sucrose, leaf chlorosis occurred and shoots gradually declined. Best rooting percentage was obtained on WPM supplemented with 1 M naphthaleneacetic acid. Rooted plantlets were acclimatized under intermittent mist. However, survival rate was relatively low (20 to 30%).     

Micropropagation ofGmelina arborea

Multiple shoots were obtained from single node explants of matureGmelina arborea Roxb. on MS medium supplemented with 6-benzyladenine (BA). Seven to nine shoots were formed whenin vitro-derived single node explants were subcultured on MS medium supplemented with 1.1 M BA. For root initiation the cut ends of microshoots were pulsed for 5 min with 246 M indole-3-butyric acid and transferred to a plastic cup containing sterile vermiculite. The shoots were covered with polyethylene bag and maintained in a culture room. After hardening, plantlets were transferred to earthen pots containing a mixture of garden soil: compost and have been established in the field.