AJOL: South African Journal of Botany: VOLUME 68 ISSUE 4 (2002) Abstracts

African Journals OnLine
South African Journal of Botany

Issues Available

VOLUME 68 ISSUE 4 (2002)
Abstracts

Minireview

Antibacterial effects of fatty acids and related compounds from plants

LJ McGaw¹, AK Jäger ^1,2 and J van Staden¹*

¹ Research Centre for Plant Growth and Development, School of Botany and Zoology, University of Natal Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa

² Department of Medicinal Chemistry, Royal Danish School of Pharmacy, Universitetsparken 2, 2100 Copenhagen 0, Denmark

* Corresponding author, email: [email protected]

Received 11 June 2002, accepted in revised form 4 October 2002

Fatty acids are important constituents of plants and are commonly known to possess antimicrobial activities. The structure-activity relationship of fatty acids, including the effects of hydrocarbon chain length, unsaturation and presence of functional groups, is reviewed. The biological activity of fatty acids is significant as they are often isolated following bioassay-guided fractionation of plant extracts. The possibility of the therapeutic use of fatty acids as antimicrobial agents is worthy of note.

Optimisation of the tissue culture protocol for the endangered Aloe polyphylla

JC Chukwujekwu, CW Fennell and J van Staden*

Research Centre for Plant Growth and Development, School of Botany and Zoology, University of Natal Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa

* Corresponding author, e-mail: [email protected]

Received 23 January 2002, accepted in revised form 11 June 2002

An optimised, rapid tissue culture protocol was established for the highly endangered Aloe polyphylla (Schonland ex Pillans). Shoot cultures of Aloe polyphylla were initiated from young shoot explants of in vitro grown plants. The basal medium was MS medium (Murashige and Skoog 1962), supplemented with 100mgl^-1 myo-inositol, and 30gl^-1sucrose. Different cytokinins (kinetin, zeatin and BA) singly or in combination with auxins (IBA and NAA), were tested for shoot proliferation activity. All the cytokinins gave good shoot proliferation. The optimal concentrations for shoot proliferation of each of the cytokinins tested were: zeatin (0.5mgl^-1), kinetin (1.5mgl^-1) and BA (1.5mgl^-1). In combination with auxins, the optimal combinations were kinetin/NAA (2.0/0.1mgl^-1), kinetin/IBA (1.5/1.0mgl^-1), zeatin/IBA (1.0/0.5mgl^-1), zeatin/NAA (1.0/1.0mgl^-1), BA/IBA (1.0/1.0mgl^-1) and BA/NAA (1.5/0.1mgl^-1). Although it gave the highest number of shoots per explant, BA (1.0–3.0mgl^-1) induced hyperhydricity. Temperature and sucrose also influenced shoot proliferation. The optimal temperature was 25°C, while 30gl^-1 was the optimal concentration of sucrose. Plants rooted well in plant growth regulator-free MS medium. Amongst the potting mixtures tested, soil:sand:vermiculite (1:1:1 v/v/v) was the best, with a 98% plantlet survival.

Growth of enset (Ensete ventricosum) suckers under different horticultural practices

M Diro^{1, 2}, S Gebremariam², A Zelleke² and J van Staden¹*

¹ Research Centre for Plant Growth and Development, School of Botany and Zoology, University of Natal Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa

² Ethiopian Agricultural Research Organisation, PO Box 2003, Addis Ababa, Ethiopia

* Corresponding author, e-mail: [email protected]

Received 11 March 2002, accepted in revised form 17 July 2002

The influence of three propagation practices and three corm types of enset on the production of suckers was investigated. After removal of apical buds, mother corms were uprooted and immediately replanted, not uprooted from original positions and uprooted and transferred to new planting holes three months later. Three corm types: whole, halved and quartered corms were used. Suckers were harvested one year after removal of apical buds. After harvest, the suckers were sorted into three size groups: undersized, small and medium to large. The number of suckers produced per plot, from four planting holes, ranged from 40 to 141 depending on the treatments. Halved and quartered mother corms, when transferred to new planting holes three months after removal of apical buds, produced fewer suckers. On the other hand, the halved corms, when uprooted and replanted immediately after removal of apical buds or not uprooted from their original growing sites, gave earlier differentiation of buds and produced more suckers. The halved corms also gave more medium to large suckers than whole and quartered corms when evaluated across all the propagation methods. An increase in the number of vigorous suckers from halved corms is possible because of elimination of the strong apical dominance while leaving reasonable portions of the mother corm to sustain initiation, growth and development of suckers. Therefore, halved corms uprooted and immediately replanted or left in situ can be used to produce more suckers with better growth.

Differential gene expression in sugarcane leaf and internodal tissues of varying maturity

DL Carson^1,2*, BI Huckett^1,2 and FC Botha²

¹ South African Sugar Association Experiment Station, Biotechnology Department, Private Bag X02, Mount Edgecombe 4300, South Africa

² Institute for Plant Biotechnology, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa

* Corresponding author, e-mail: [email protected]

Received 21 May 2002, accepted in revised form 15 July 2002

The expression patterns of sugarcane (Saccharum spp. hybrids) genes were examined in different tissue sources and at developmental stages by ‘reverse Northern’ hybridisation analysis to identify differentially expressed genes. cDNA arrays containing 1 000 random clones from an immature leaf and maturing culm cDNA library were hybridised with radioactively-labeled poly (A)+ RNA from immature leaf, mature leaf, immature culm and maturing culm. All cDNAs were found to hybridise to all four probes, but differences in signal intensity were observed for individual cDNAs between hybridisation events. No cDNAs displaying tissue- or developmental-stage specific expression were detected. Comparisons between hybridisation patterns identified 61 cDNAs that were more abundantly expressed in immature and mature leaf than the culm. Likewise, 25 cDNAs preferentially expressed in immature and maturing culm were detected. ESTs established for the differentially expressed cDNAs revealed sequence homology to a diverse collection of genes in both the leaf and the culm. These included genes associated with general cellular metabolism, transport, regulation and a variety of stress responses. None of the differentially expressed genes identified in the culm were homologous to genes known to be associated with sucrose accumulation. These preliminary gene expression profiling results suggest that the genetic regulation of processes related to sugarcane leaf and culm maturation is very complex.

The horizontal distribution of root biomass in a South African winter-rainfall desert community

KJ Esler¹*, RM Cowling² and NS Eccles³

¹ Department of Botany, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa

² Terrestrial Ecology Research Unit, Department of Botany, University of Port Elizabeth, PO Box 1600, Port Elizabeth 6000, South Africa

³ Institute for Plant Conservation, Department of Botany, University of Cape Town, Private Bag, Rondebosch 7700, South Africa

* Corresponding author, e-mail: [email protected]

Received 29 January 2002, accepted in revised form 31 July 2002

We address the question of whether the spatial distribution of root biomass mirrors the highly clumped distribution of shoot biomass in two desert plant communities (short and medium strandveld) on the west coast of South Africa. Results indicate that this is generally not the case. In both communities, there was no significant difference between the fine root (<2mm diameter) biomass under clumps compared with gaps between clumps. In the short strandveld, this was also the case for structural root mass. The only exception to this general trend was in the case of structural roots in the medium strandveld where there was more biomass under vegetation clumps. These patterns suggest that strandveld plants are shaped by the trade off between advantages of clumping and the inevitable competition for water that this association brings. In these communities, the competitive disadvantages of clumping above-ground may be offset by root foraging between clumps. Fertile islands do not seem to be a feature of these communities.

An in vitro production and field transfer protocol for Solanum melongena L. plants

RM Taha* and M Tijan

Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia

* Corresponding author, e-mail: [email protected]

Received 18 March 2002, accepted in revised form 31 July 2002

In vitro plantlet regeneration studies were initiated from various vegetative organs of Solanum melongena L. Best shoot regeneration (25 shoots per explant) was obtained from leaf and stem explants (17 shoots per explant) cultured on MS medium supplemented with 0.5mg/l Naphthalene acetic acid (NAA), although multiple shoots were observed routinely on MS basal and MS containing 1.0–6.0mg/l NAA on both leaf and stem explants. Rooting of shoots (approximately 100%) was achieved on MS basal medium. Regenerated plantlets were then acclimatised by transferring them to enclosed glass containers (18cm x 18cm x 25cm) which had the lids opened 5–10 minutes each day for 14 days. The plantlets were then transferred to fields with no shades with 80% success; plants that survived produced fruits. Karyotype analysis coupled with measurement of the mitotic index revealed neither somaclonal variation nor impaired frequency of cell division.

Abbreviations: BA = benzyl adenine, IAA = indole-3-acetic acid, IBA = indole-3-butyric-acid, NAA = naphthalene acetic acid

An analysis of the performance of an artificial wetland for nutrient removal in solar saltworks

SR du Toit and EE Campbell*

Department of Botany, University of Port Elizabeth, Port Elizabeth 6031, South Africa

* Corresponding author, e-mail: [email protected]

Received 22 April 2002, accepted in revised form 12 August 2002

A small artificial wetland was constructed through which intake water flowed before entering the initial pond of a solar saltworks. This trial wetland was designed for the removal of excessive nutrients from the water as the system is becoming hypertrophic. Spartina maritima (Curtis) Fernald was the dominant halophytic grass used in the wetland and Ulva rigida C. Agardh the dominant macroalga. The nutrient content of the inflow and outflow water of the wetland was monitored for eight months after construction. For seven out of nine analyses, the ammonium concentrations of water flowing out of the wetland were significantly reduced (by an average of 56%) when compared to those measured in water flowing into the wetland. Nitrate and phosphate concentrations for eight out of nine analyses also showed significant reductions (by 60% and 56% respectively). The success of this wetland indicates that it can be an effective management tool for nutrient reduction in solar saltworks.

Germ-furrow morphology and storage conditions determine the degree of viability of Pinus caribaea pollen

JH Doyle¹, RL Verhoeven², C Bester³, BD Wingfield¹ and A-M Botha¹*

¹ Department of Genetics, Forestry and Agriculture Biotechnology Institute, University of Pretoria, Pretoria 0002, South Africa

² Department of Plant Sciences, University of the Free State, Bloemfontein 9300, South Africa

³ Komatiland Forests Research, Research: Sabie, PO Box 574, Sabie 1260, South Africa

* Corresponding author, e-mail: [email protected]

Received 13 June 2002, accepted in revised form 19 August 2002

This study has found a correlation between Pinus caribaea pollen morphology and viability. Eighteen different P. caribaea pollen families were screened to determine the effect of environmental conditions during storage on germination. The results indicated that there was a direct decrease in viability with an increase in the age of the pollen, temperature at which the pollen was stored, and exposure to high humidity during storage. Scanning electron microscopy was used to investigate the dimensions of the 18 families. Upon statistical analysis of the dimensional data, the families were found to group into three clusters. Pollen families displaying narrow germ furrows clustered with those displaying wide germ furrows, while those pollen families displaying intermediate germ furrows clustered into a second group. When the clusters were compared with the germination data obtained it was found that the pollen families displaying highest germination percentages fell into the intermediate cluster, while the pollen families displaying low to intermediate germination percentages fell into the narrow/wide cluster.

Interpretation of late Holocene pollen in channel fills in the eastern Free State, South Africa, in terms of local conditions and sediment reworking

M Nyakale and L Scott*

Department of Plant Sciences, University of the Free State, PO Box 339, Bloemfontein, South Africa

* Corresponding author, e-mail: [email protected]

Received 10 April 2002, accepted in revised form 29 August 2002

Channel deposits of two cut and fill cycles in swampy deposits from the eastern Free State contain organic layers and some of these include pollen. Radiocarbon dating of the basal organic layers in the two channels gives indications of a late Holocene age but they provide an inverted chronological sequence. This discrepancy is interpreted as possible re-deposition of organic material from older up-stream deposits. This problem suggests that narrow channel fills are not ideal for environmental reconstruction and should be avoided in favour of wide low energy valley fills, which can be found in the eastern highlands. The pollen contents of the two sequences nevertheless, suggest marked variation that indicates climate variability during the Holocene in the area. The general pollen contents in the channel deposits appear typical of the regional grassland (Scott 1989) except for relatively high proportions of Asteraceae and smooth trilete fern spores. A possible explanation for the prominent Asteraceae may be found in relatively dry, sandy conditions on the north facing slope where the site is situated, while the trilete spores are possibly derived from upslope vegetation of rocky outcrops.

Ozone stress in rust resistant and susceptible Helianthus annuus cultivars as measured with chlorophyll fluorescence

JU Grobbelaar¹* and FH Mohn²

¹ Department of Botany, University of the Free State, Bloemfontein 9300, South Africa

² Institute for the Chemistry of the Geosphere 6, Research Centre Jülich, D-52425 Jülich, Germany

* Corresponding author, e-mail: [email protected]

Received 19 March 2002, accepted in revised form 30 August 2002

Rust resistant and susceptible cultivars of Helianthus annuus were exposed for short periods to 230ppb ozone, a concentration often measured in central Europe and elsewhere during summer months. Chlorophyll fluorescence induction was used to measure a number of photosynthetic parameters. The stress caused was detectible within minutes following exposure to ozone. Measurements of f_max and f_ss showed that only the susceptible cultivar was stressed. However, following F_s and F_m, fluorescence over long periods, it was clear that both cultivars were stressed by ozone. Subsequent to the fumigation with ozone, the resistant cultivar restored to levels prior to exposure to ozone, indicating repair to the damage caused. Both cultivars showed repair during the dark, while the damage caused to the susceptible cultivar appeared to be permanent. Both the utilisation of excitons as well as the number of closed versus open reaction centres were influenced by the ozone. Resistance to a stressor (in this case to rust) was beneficial to the plants, indicating a common response to stress and also adaptation to stressors.

Abbreviations: CSTR = continuously stirred tank reactor, ETR = electron transport rate, F₀ = minimal fluorescence of a dark-adapted sample, F_m = maximal fluorescence of a dark-adapted sample, F_s = minimum steady state fluorescence, F_m, = maximum steady state fluorescence, f_max = maximum yield of primary photochemistry, f_ss = steady state quantum yield, pQ = photochemical quenching, RC = reaction centre

Vegetation ecology of Sekhukhuneland, South Africa: Combretum hereroense–Grewia vernicosa Open Mountain Bushveld

SJ Siebert^1,2*, AE van Wyk¹ and GJ Bredenkamp¹

¹ Department of Botany, University of Pretoria, Pretoria 0002, South Africa

² Present address: SABONET, c/o National Botanical Institute, Private Bag X101, Pretoria 0001, South Africa

* Corresponding author, e-mail: [email protected]

Received 18 September 2001, accepted in revised form 30 August 2002

A hierarchical classification, description, and ecological and floristic interpretations are presented on one of the six major vegetation types of the Sekhukhuneland Centre of Plant Endemism, namely the Combretum hereroense–Grewia vernicosa Open Mountain Bushveld. Relevés were compiled in 91 stratified random plots. A TWINSPAN classification, refined by Braun-Blanquet procedures, revealed 20 plant communities, which are divided into six associations and 19 sub-associations. Many new syntaxa are described and ecologically interpreted. For each of the plant communities the species richness, endemism and conservation status were determined. A selected set of environmental factors is provided to aid with the delimitation of plant communities. The floristic information, proposed classification, general description and vegetation key can be used for future identification of conservation areas, land-use planning and further research.

Vegetation ecology of Sekhukhuneland, South Africa: Kirkia wilmsii–Terminalia prunioides Closed Mountain Bushveld

SJ Siebert^1,2*, AE van Wyk¹ and GJ Bredenkamp¹

¹ Department of Botany, University of Pretoria, Pretoria 0002, South Africa

² Present address: SABONET, c/o National Botanical Institute, Private Bag X101, Pretoria 0001, South Africa

* Corresponding author, e-mail: [email protected]

Received 2 April 2002, accepted in revised form 16 September 2002

A hierarchical classification, description, and ecological and floristic interpretations are presented on one of the six major vegetation types of the Sekhukhuneland Centre of Plant Endemism, namely the Kirkia wilmsii–Terminalia prunioides Closed Mountain Bushveld. Relevés were compiled in 103 stratified random plots. A TWINSPAN classification, refined by Braun-Blanquet procedures, revealed 20 plant communities, which are divided into five associations and 20 sub-associations. Many new syntaxa are described and ecologically interpreted. For each of the plant communities the floristic richness, endemism and conservation status was determined. A selected set of environmental factors is provided to aid with the delimitation of plant communities. The floristic information, proposed classification, general description and vegetation key, can be used for the identification of conservation areas, land-use planning and further research.

Developmental changes of superoxide dismutase, peroxidase and catalase isoenzyme profiles in leaves of Impatiens flanaganiae Hemsl. associated with variations in light intensity

N Lall¹* and RV Nikolova²

¹ Department of Botany, University of Pretoria, Pretoria 0002, South Africa

² Department of Botany, University of Transkei, Private Bag X1, Umtata 5100, South Africa

Present address: Department of Botany, University of the North, Private Bag X1106, Sovenga 0727, South Africa

* Corresponding author, e-mail: [email protected]

Received 15 January 2002, accepted in revised form 16 September 2002

Changes in isoenzyme profiles of antioxidative enzymes, superoxide dismutase, peroxidase and catalase, in leaves of Impatiens flanaganiae Hemsl. subjected to different light conditions were investigated. Unbranched plantlets of I. flanaganiae propagated from tubers were exposed to three light regimes: 55µmol m^-2 sec^-1, 280µmol m^-2 sec^-1 and 30µmol m^-2 sec^-1 (variants I, II and III respectively) for a period of seven weeks. Isoenzymes of superoxide dismutase, peroxidase and catalase and their differential responses to light variations were studied in plant extracts prepared from leaves of all three variants at weekly intervals. The activity of most SOD isoenzymes from plants subjected to low light intensity (variants I and II) remained relatively constant except for one Cu/Zn-SOD that increased gradually during the course of development. Little or no change in catalase activity was observed during the initial stage development of plants from these variants. A profound enhancement of catalase level was detected only from the fifth week onward, especially in variant III. The induction of some SODs and CAT in plants from these variants could be related to possible oxidative stress associated with plant aging. In contrast to CAT, the activity of some of the peroxidase isoenzymes in variant III decreased from the second week onward and was lower than in the plants from the other two variants during the initial stages of development. Plants from variants I and III also showed a steady increase in activity of most isoperoxidases (low and high mobility) with time, which suggests their indirect involvement in the regulation of plant growth and development. A rapid increase in the activity of superoxide dismutase and catalase during the experimental period was observed in plants exposed to relatively high light intensity (variant II). The activities of both Mn, and some of the Cu/Zn-containing SODs increased sharply from the second week onward under high light intensity as compared to the other two variants subjected to low light intensity. The Mn-SOD activity remained high throughout the experimental period, while the light-induced Cu/Zn-SODs showed a reduction in activity after the third week. This light-induced response could be an attempt to protect plants from the harmful radicals generated due to photo-oxidative stress under high light. The low activity of some isoperoxidase observed under these conditions is considered to be compensated by high catalase activity as the active oxygen species, hydrogen peroxide, is removed by catalase and/or peroxidase. These metal containing enzymes seem to respond differentially to variations in light and could be suitable as a marker for the evaluation of light-induced oxidative stress in Impatiens flanaganiae plants.

The effect of smoke on the photosynthetic gas exchange of Chrysanthemoides monilifera

ME Gilbert and BS Ripley*

Botany Department, Rhodes University, Grahamstown 6140, South Africa

* Corresponding author, e-mail: [email protected]

Received 22 April 2002, accepted in revised form 16 September 2002

The effect of smoke on the germination of various fynbos species has been well documented. However, little work has been done on the effect of smoke on mature plants. This study investigated the effect of smoke on the photosynthetic gas exchange of Chrysanthemoides monilifera. Potted plants given a one-minute exposure to smoke were significantly affected within half an hour. Stomatal conductance, CO₂ assimilation rate and intercellular CO₂ levels were significantly reduced and these reductions persisted for five hours, subsequent to which the three parameters recovered to control levels over the next 24h. Reduction in CO₂ assimilation rate was the consequence of both stomatal and mesophyll effects, the latter including decreases in both carboxylation efficiency and RuBP regeneration capacity. The factors responsible for these effects appear not to be related to the temperature or CO₂ concentrations of the smoke and further investigation is required to elucidate the causal factor(s). Unlike gas exchange parameters, PSII photochemical efficiency was unaffected by the treatment. Repeated exposure to similar smoke treatments resulted in acclimation such that no significant reductions in CO₂ assimilation rate or stomatal conductance were evident, after a smoke treatment. The photosynthetic gas-exchange of field grown plants, measured two weeks subsequent to the exposure to smoke from a natural fire, showed no response. A result that was anticipated from laboratory studies where recovery following single smoke exposure was shown to occur within 24h.

The genetic diversity of Scaevola plumieri (Goodeniaceae), an indigenous dune coloniser, as revealed by Inter Simple Sequence Repeat (ISSR) fingerprinting

NP Barker¹*, KT Harman¹, BS Ripley¹ and J Bond²

¹ Department of Botany, Rhodes University, PO Box 94, Grahamstown 6140, South Africa

² Centre for Ecology and Hydrology Dorset, Winfrith Technology Centre, Dorchester DT2 8ZD, United Kingdom

* Corresponding author, e-mail: [email protected]

Received 18 February 2002, accepted in revised form 16 September 2002

Scaevola plumieri L. is one of the major primary dune colonisers on the eastern seaboard of southern Africa, and plays a vital role in dune stabilisation in this dynamic environment. Little is known about the reproductive biology of this species. The genetic diversity of populations of Scaevola plumieri within its South African range was examined using Inter Simple Sequence Repeats (ISSR). Genetic profiles from individual plants from 16 populations were generated. These were used to calculate pairwise genetic distances between individual samples. UPGMA analyses based on 104 polymorphic bands revealed 40 genotypes, and showed that all populations were genetically distinct from each other. Character compatibility analysis indicated that there was little evidence of a clonal habit, and splits tree analyses indicated horizontal patterns of diversity, suggesting that populations are reproducing sexually between dunes. It was concluded that individual isolated dunes usually comprise individual plants or clones, but reproduction between dunes and populations was of a more sexual nature. Genetic data confirm observations of very low establishment rates of S. plumieri seedlings; seedlings typically succumb to desiccation, over-wash and burial. Despite low dispersal and subsequent establishment rates the plants are abundant and cover vast areas of dunes along the east coast, and results obtained here suggest that each individual or vegetatively produced genet can become very large.

Short Communication

Cell cultures of Pueraria lobata (Willd.): growth and production of isoflavones and puerarin

HL Liu and L Li*

Department of Biology, South China Normal University, Guangzhou, 510631, China

* Corresponding author, e-mail: [email protected]

Received 18 March 2002, accepted in revised form 24 July 2002

Callus and suspension cultures of Pueraria lobata were established in Gamborg B5 medium supplemented with 1mg l^-1 2,4-dichlorophenoxyacetic acid, 1mg l^-1 a-naphthalene acetic acid, 0.5mg l^-1 kinetin and 30g l^-1 sucrose. The content of total isoflavones and puerarin in the natural roots, callus and suspension cultures were quantitatively compared spectrophotometrically and by HPLC. Secondary product production was lower in the in vitro grown material.

Abbreviations: BA = benzylaminopurine, 2,4-D = dichlorophenoxyacetic acid, NAA = a-naphthalene acetic acid, K = kinetin, IFS = 2-hydroxyisoflavanone synthase, IFD = 2-hydroxyisoflavanone dehydratase, CHS = chalcone synthase, PAL = phenylalanine ammonia-lyase

Short Communication

Characterisation of two desiccation-stress related cDNAs TrDr1 and TrDr2 in the resurrection moss Tortula ruralis

K Triwitayakorn and AJ Wood*

Department of Plant Biology, Southern Illinois University-Carbondale, Carbondale, IL 62901-6509, United States of America

* Corresponding author, e-mail: [email protected]

Received 17 April 2002, accepted in revised form 24 July 2002

Two EST-derived cDNAs TrDr1 and TrDr2 from Tortula ruralis were identified with significant similarity to psbI encoding the PSII 10kDa protein and the desiccation stress-related cDNA pcC3-06, respectively. RNA blot hybridisation using both total and polysomal RNA fractions was used to analyse TrDr1 and TrDr2 mRNA abundance in response to a desiccation/rehydration cycle. TrDr1 and TrDr2 steady-state transcript levels increased in response to desiccation and preferentially accumulated within the polysomal mRNA fraction. The data suggest that TrDR1 and TrDR2 play a role in vegetative desiccation-tolerance.

Abbreviations: EST, expressed sequence tag; PSII, photosystem II

Research Note

An improved DNA extraction procedure for plant tissues with a high phenolic content

PN Hills and J van Staden*

Research Centre for Plant Growth and Development, School of Botany and Zoology, University of Natal Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa

* Corresponding author, email: [email protected]

Received 28 August 2002, accepted 29 August 2002

Isolation of DNA from plant tissues which have a high phenolic content is often difficult. Tagetes minuta L. achenes have darkly pigmented fruit walls and it is exceptionally difficult to isolate nucleic acids from them. These achenes thus served as a good model for the development of a modified DNA extraction procedure which works well for tissues with a high phenolic content.

AJOL Home Page

How to order photocopies

Order Forms

INASP Home Page

African Journals OnLine South African Journal of Botany

VOLUME 68 ISSUE 4 (2002) Abstracts

African Journals OnLine
South African Journal of Botany

VOLUME 68 ISSUE 4 (2002)
Abstracts