Abstract
During studies to optimize production of morphogenic callus from cultured leaf discs of sugarbeet (Beta vulgaris L.) large differences were observed associated with the gelling agent employed. Water availability, as determined mainly by gel matric potential, was found to be the dominant factor. A simple method was devised to measure the relative matric potential of different gels. A precisely moistened filter-paper disc was placed on the gel surface, allowed to equilibrate, removed and weighed. The relative gain or loss of water from the paper disc was a measure of the matric potential of the gel and varied with both gel type and concentration. Leaf disc expansion and production of callus-derived embryos and shoots were shown to be directly proportional to gel matric potential. Water availability may also be affected by the ease with which liquid is expressed from gels in response to localized pressure caused by explant expansion and contortion. This property, called gel expressibility, was easily measured with a weight and capillary pipette and shown also to vary with gel type and concentration. Validity of the technique for measuring relative matric potential was verified physiologically by culturing leaf discs on filter-paper overlays to eliminate expressibility differences among gels. Additionally, comparison of leaf disc growth on uncovered gel surfaces versus filter-paper overlays demonstrated the contribution of liquid expression to overall water availability. Expression of liquid by explants on uncovered gel surfaces greatly enhanced the production of morphogenic callus.
Similar content being viewed by others
References
Boyer JS (1985) Water transport. In: Briggs WR, Jones RL & Walbot V (Eds) Ann. Rev. Plant Physiol. 36: 473–516. Annual Reviews Inc., Palo Alto
Brown DCW, Leung DWM & Thorpe TA (1979) Osmotic requirement for shoot formation in tobacco callus. Physiol. Plant. 46: 36–41
Campbell GS & Gee GW (1986) Water potential: Miscellaneous methods. In: Klute A (Ed) Methods of Soil Analysis, Part 1. Physical and Mineralogical Methods-Agronomy Monograph no. 9 (2nd Edition) (pp 619–633). American Society of Agronomy-Soil Science Society of America, Madison
Debergh PC (1983) Effects of agar brand and concentration on the tissue culture medium. Physiol. Plant. 59: 270–276
Debergh P, Harbaoui Y & Lemeur R (1981) Mass propagation of globe artichoke (Cynara scolymus): Evaluation of different hypotheses to overcome vitrification with special reference to water potential. Physiol. Plant. 53: 181–187
Dunnet CW (1964) New tables for multiple comparisons with a control. Biometrics 20: 482–491
Freytag AH, Anand SC, Rao-Arelli AP & Owens LD (1988) An improved medium for adventitious shoot formation and callus induction in Beta vulgaris L. in vitro. Plant Cell Rep. 7: 30–34
Horsch RB, Fry J, Hoffmann N, Neidermeyer J, Rogers SG & Fraley RT (1988) Leaf disc transformation. In: Gelvin SB & Schilperoort RA (Eds) Plant Molecular Biology Manual (pp A5/1–9). Kluwer Academic Publishers, Boston
Jia S-R, Yang M-Z, Ott R & Chua N-H (1989) High frequency transformation on Kalanchoe laciniata. Plant Cell Rep. 8: 336–340
Mackay WA & Kitto SL (1988) Factors affecting in vitro shoot proliferation of French tarragon. J. Amer. Soc. Hortic. Sci. 113: 282–287.
McQueen IS & Miller RF (1968) Calibration and evaluation of a wide-range gravimetric method for measuring moisture stress. Soil Sci. 106: 225–231
Murashige T & Skoog F (1962) A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol. Plant. 15: 473–479
Papendick RI & Campbell G S (1980) Theory and measurement of water potential. In: Parr JF, Gardner WR & Elliot LF (Eds) Water Potential Relations in Soil Microbiology (pp 1–22). Soil Science Society of America, Madison
Pasqualetto P-L, Zimmerman RH & Fordham I (1986) Gelling agent and growth regulator effects on shoot vitrification of ‘Gala’ apple in vitro. J. Amer. Soc. Hortic. Sci. 111: 976–980
Pasqualetto P-L, Zimmerman RH & Fordham I (1988) The influence of cation and gelling agent concentrations on vitrification of apple cultivatars in vitro. Plant Cell Tiss. Org. Cult. 14: 31–40
Romberger JA & Tabor CA (1971) The Picea abies shoot apical meristem in culture. I. Agar and autoclaving effects. Amer. J. Bot. 58: 131–140
Saunders JW & Shin K (1986) Germplasm and physiologic effects on induction of high-frequency hormone autonomous callus and subsequent shoot regeneration in sugarbeet. Crop. Sci. 26: 1240–1245
Singha S (1982) Influence of agar concentration on in vitro shoot proliferation of Malus sp. ‘Almey’ and Pyrus communis ‘Seckel’. J. Amer. Soc. Hortic. Sci. 107: 657–660
Stoltz LP (1971) Agar restriction of the growth of excised mature iris embryos. J. Amer. Soc. Hortic. Sci. 96: 681–684
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Owens, L.D., Wozniak, C.A. Measurement and effects of gel matric potential and expressibility on production of morphogenic callus by cultured sugarbeet leaf discs. Plant Cell Tiss Organ Cult 26, 127–133 (1991). https://doi.org/10.1007/BF00036116
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00036116