Xylem and Phloem Derived Polyamines during Flowering in Two Diverse Rose Species
- 119 Downloads
Polyamine contents in xylem (root) and phloem (leaf) exudates in two diverse species of rose, viz. Rosa damascena Mill and Rosa bourboniana Desport, were analyzed before, during, and after flowering in the main flowering season, that is, April–May. Only free putrescine (Put) was detected in the xylem and phloem exudates at these time points, and it was high during the peak flowering period. In phloem, Put content was significantly higher in R. bourboniana than in R. damascena at all three stages; whereas in the xylem exudate it was relatively higher in R. damascena at the peak flowering period. A spray of α-difluoromethylornithine (DFMO), an irreversible inhibitor of the putrescine biosynthetic inhibitor ornithine decarboxylase (ODC), markedly decreased the flowering. This effect was reversed by application of Put alone or in combination with DFMO. The significance of this finding is discussed in light of polyamine translocation during flowering.
Key words:Flower development Phloem Polyamines Rosa bourboniana Rosa damascena Translocation Xylem.
The authors thank, Dr. P. S. Ahuja, Director, IHBT for necessary facilities; Department of Science and Technology, New Delhi, for financial support in the form of a research project; and Dr. Manoj K. Singh for help in statistical analysis.
- Beraud J, Braun A, Feray A, Hourmant A, Pernot M. 1992. Long distance transport of 14 C putrescine in potato plantlets (Solanum tuberosum cv. Bintje). Biochem Physiol Pflanzen 188:169–176Google Scholar
- Caffaro SV, Scaramagli S, Antognoni F, Bagni N. 1993. Polyamine content and translocation in soyabean plants. J Plant Physiol 41:563–568Google Scholar
- Caffaro SV, Vicente C. 1995. Early changes in the content of leaf polyamines during the photoperiodic flowering induction in soybean. J Plant Physiol 145:756–758Google Scholar
- Dumortier FM, Flores HE, Shekhawat NS, Galston AW. 1983. Gradients of polyamines and their biosynthetic enzymes in coleoptiles and roots of corn. Plant Physiol 72:915–918Google Scholar
- Friedman R, Levin N, Altman A. 1986. Presence and identification of polyamines in xylem and phloem exudates of plants. Plant Physiol 82:1154–1157Google Scholar
- Galston AW, Kaur-Sawhney R, Altabella T, Tiburcio AF. 1997. Plant polyamines in reproductive activity and response to abiotic stress. Bot Acta 110:198–207Google Scholar
- Gomez KA, Gomez AA. 1984. Statistical procedures for agricultural research. John Wiley and Sons, New York, 680 pGoogle Scholar
- King RW, Zeevaart JAD. 1974. Enhancement of phloem exudation from cut petioles by cnelating agents. Plant Physiol 53:96–103Google Scholar
- Lejeune P, Kinet JM, Bernier G. 1988. Cytokinin fluxes during floral induction in the long day plant Sinapis alba L. Plant Physiol 86:1095–1098Google Scholar
- Slocum RD, Flores HE. 1991. Biochemistry and physiology of polyamines in plants. CRC Press, Boca Raton, FL, p. 264Google Scholar
- Sood S, Nagar PK. 2004. Changes in endogenous polyamines during flower development in two diverse species of rose. Plant Growth Regul 44:117–123Google Scholar
- Wada N, Shinozaki M, Iwamura H. 1994. Flower induction by polyamines and related compounds in seedlings of Morning Glory (Pharbitis nil, cv. Kidachi). Plant Cell Physiol 35:469–472Google Scholar