1887

Abstract

Since polyamines (PAs) play a potential role in the regulation of growth and developmental processes in a wide variety of organisms, we have examined the influence of the PAs putrescine (Put) and spermidine (Spd) and the PA biosynthetic inhibitors -difluoromethylornithine (DFMO), -difluoromethylarginine (DFMA), methylglyoxal -(guanylhydrazone) (MGBG) and cyclohexylamine (CHA), singly and in combinations on microcycle conidiation (MC) in The exogenous application of the diamine Put (concentrations ranging from 0·1 to 5 mM) caused a sharp decline of MC in a dose-dependent fashion, but induced vegetative growth. However, the triamine Spd (0·1-5 mM) had a minimal effect on MC and induced a shift from MC to normal conidiation. PA inhibitors, especially DFMO, MGBG and CHA, produced greater inhibition of MC and complete inhibition of MC was observed at 5 mM of these inhibitors. DFMA even at 5 mM had only a weak inhibitory effect on MC. DFMO also inhibited conidial germination and germ tube growth. MGBG and CHA, while having an inhibitory effect on MC, induced vegetative growth. The inhibitory effect of PA inhibitors was partially reversed by exogenous Put or Spd, with Spd being more effective than Put. The analysis of free PA levels during various phases of MC revealed that undifferentiated spores contained a high Put/Spd ratio and there was a dramatic decrease in Put/Spd ratio before and during microcycle conidiophore maturity. The change in spermine titres could not be detected. These observations imply that Put is essential for vegetative growth, while Spd is involved in MC, and that a low Put/Spd ratio seems to be important for spore differentiation to MC.

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1996-03-01
2021-08-03
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References

  1. Akhtar J. K., Minocha S. C. 1989; Polyamine biosynthetic enzymes and the effect of their inhibition on the growth of some phytopathogenic fungi. Plant Cell Physiol 30:655–663
    [Google Scholar]
  2. Anderson J. G., Smith J. E. 1971a; The production of conidiophores and conidia by newly germinated conidia of Aspergillus niger (microcycle conidiation). J Gen Microbiol 69:185–197
    [Google Scholar]
  3. Anderson J. G., Smith J. E. 1971b; Synchronous initiation and maturation of Aspergillus niger conidiophores in culture. Trans Br My col Soc 56:9–29
    [Google Scholar]
  4. Bajaj S., Rajam M. V. 1995; Efficient plant regeneration from long-term callus cultures of rice by spermidine. Plant Cell Rep 14:717–720
    [Google Scholar]
  5. Bharti. 1995; Inhibition of fungal polyamine biosynthesis and control of leaf rust of wheat (Triticum aestivum L.): physiological and cytogenetical studies in the host plant. PhD thesis, University of Delhi India:
    [Google Scholar]
  6. Bharti, Rajam M. V. 1995; Effects of the polyamine biosynthesis inhibitor difluoromethyl-ornithine on growth, polyamine levels, chromosome behaviour and polygenic traits in wheat (Triticum aestivum L.). Ann Bot 76:297–301
    [Google Scholar]
  7. Birecka H., Garraway M. O., Baumann R. I., McCann P. P. 1986; Inhibition of ornithine decarboxylase and growth of the fungus Helminthosporium maydis . Plant Physiol 80:798–800
    [Google Scholar]
  8. Brawley J. V., Ferro A. J. 1979; Polyamine biosynthesis during germination of yeast ascospores. J Bacterial 140:649–654
    [Google Scholar]
  9. Calvo-Mendez C., , Martinez-Pacheco M., Ruiz-Herrera J. 1987; Regulation of ornithine decarboxylase activity in Mucor bacilliformis and Mucor rouxii . Exp Mycol 11:270–277
    [Google Scholar]
  10. Feirer R., Mignon G., Litvay J. D. 1984; Arginine decarboxylase and polyamines required for embryogenesis in the wild carrot. Science 223:1433–1435
    [Google Scholar]
  11. Gaur S. C., Shekhawat N. S., Arya H. C. 1989; Growth and sporulation of millet leaf blast fungus Pyricularia penniseti: role of polyamines. Curr Sci 58:198–200
    [Google Scholar]
  12. Kaur-Sawhney R., , Tiburcio A. F., Galston A. W. 1988; Spermidine and flower bud differentiation in thin-layer explants of tobacco. Planta 173:282–284
    [Google Scholar]
  13. Khurana N., Gupta R., Kuhad R. C., Saxena R. K. 1992; Effect of protein synthesis and respiratory inhibitors on microcycle conidiation of Aspergillus tamarii . J Gen Appl Microbiol 38:617–621
    [Google Scholar]
  14. Khurana N., Gupta R., Kuhad R. C., Saxena R. K. 1993; Light independent conidiation in Trichoderma spp. - a novel approach to microcycle conidiation. World J Microbiol & Biotechnol 9:353–356
    [Google Scholar]
  15. Kim W. K. 1971; Folate and polyamine content of undiffrentiated and differentiated wheat stem rust uredosporelings. Can J Bot 49:1119–1122
    [Google Scholar]
  16. Machatsckke S., Kamrowski C., Moerschbacher B. M., Reisenger H. J. 1990; Polyamine levels in stem rust infected wheat leaves and effects of alpha-difluoromethylornithine on fungal infection. Physiol Mol Plant Physiol 36:451–459
    [Google Scholar]
  17. Maheshwari R. 1991; Microcycle conidiation and its genetic basis in Neurospora crassa . J Gen Microbiol 137:2103–2115
    [Google Scholar]
  18. Martinez-Pacheco M., , Rodriguez G., Reyna G., Calvo-Mendez C., Ruiz-Herrera J. 1989; Inhibition of the yeast mycelial transition and the phorogenesis of Mucorales by diaminobutanone. Arch Microbiol 151:10–14
    [Google Scholar]
  19. Rajam M. V. 1993; Polyamine biosynthesis inhibitors : new protectants against fungal plant diseases. Curr Sci 65:461–469
    [Google Scholar]
  20. Rajam M. V., Galston A. W. 1985; The effects of some polyamine biosynthetic inhibitors on growth and morphology of phytopathogenic fungi. Plant Cell Physiol 26:683–692
    [Google Scholar]
  21. Rajam M. V., Weinstein L. H., Galston A. W. 1985; Prevention of a plant disease by specific inhibition of fungal polyamine biosynthesis. Proc Natl Acad SciUSA 826874–6878
    [Google Scholar]
  22. Rajam M. V., Weinstein L. H., Galston A. W. 1986; Kinetic studies on the control of the bean rust fungus (Uromycesphaseoli L.) by an inhibitor of polyamine biosynthesis. Plant Physiol 82:485–487
    [Google Scholar]
  23. Rajam M. V., Weinstein L. H., Galston A. W. 1989; Inhibition of uredospore germination and germ tube growth by inhibitors of polyamine metabolism in Uromyces phaseoli L. Plant Cell Physiol 30:37–41
    [Google Scholar]
  24. Saxena R. K. 1976; Studies on the control of reproductive differentiation in Aspergillus nidulans under submerged culture conditions. PhD thesis, University of Delhi
    [Google Scholar]
  25. Saxena R. K., Sinha U. 1973; Conidiation of Aspergillus nidulans in submerged liquid culture. J Gen Appl Microbiol 19:141–146
    [Google Scholar]
  26. Saxena R. K., Khurana N., Kuhad R. C., Gupta R. 1992; d-Glucose soluble starch, a novel medium for inducing microcycle conidiation in the genus Aspergillus . Mycol Res 96:490–494
    [Google Scholar]
  27. Singhania S., Satyanarayana T., Rajam M. V. 1991; Poly-amines of thermophilic moulds: distribution and effect of poly-amines biosynthesis inhibitors on growth. Mycol Res 95:915–917
    [Google Scholar]
  28. Stevens L., Winther M. D. 1979; Spermine, spermidine and putrescine in fungal development. Adv Microb Physiol 19:63–148
    [Google Scholar]
  29. Tabor C. W., Tabor H. 1985; Polyamines in microorganisms. Microbiol Rev 49:81–99
    [Google Scholar]
  30. Walters D. R. 1987; Polyamines: the Cinderellas of cell biology. Biologist 34:73–76
    [Google Scholar]
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