Peculiarities Of Growth And Lipoxygenase Activity Of Wild Fern Dryopteris Filix-mas (l.) Schott
Abstract
L.M. Babenko, I.V. Kosakivska, L.V. Voytenko
We studied the peculiarities of growth, localization and dynamics of lipoxygenase activity in sporophyte organs of wild fern Dryopteris filix-mas (L.) Schott at various phases: intensive growth; sori ripening; spore release; summer vegetation, and vegetation termination. Morphometric analysis showed that the weight of one plant during sporophyte ontogenesis varied from 130 to 150 g. Frond length varied from 11 to 85 cm. Diameter of the overground part of rhizome was 9-10 cm. In the phase of spore release and during the summer vegetation we mentioned 7 fronds on plant, and in the phase of vegetation termination – 18. The plants had the biggest weight in phase of spore release. Following spore release and at the beginning of vegetation termination, the frond weight diminished almost by two times. An intensive elongation of fronds was observed prior to the start of spore release. When fronds unfold and grow the number of segments of the first order increase from 39 to 47 pairs. Frond length in the phase of summer vegetation increased from 4.3 to 11.2 cm (9 pairs), and then it gradually decreased from 10.2 to 0.1 cm (39 pairs) that resulted in the formation of a lanceolate lamina. In the phase of vegetation termination, the fern had 18 fronds, 12 of which remained green, while the rest dried and turned greyish-brown. The frond lamina contained 47 pairs of segments of the first order whose length increased from 4.5 to 10.5 cm, and then it diminished from 9.5 to 0.05 cm. The rhizome weight was in the range of 110.2–115.7 g in all phases except the phase of vegetation termination. The morphological analysis showed that plants had successfully passed all developmental phases, reached their normal dimensions, had a mass spore formation, no external signs of suppression and damages, and this was generally consistent with the highest level of life state assessment. Localization and dynamics of lipoxygenase (LOX) activity in organs of the sporophyte of D. filix-mas have been studied. We registered that fronds contained 13-LOX with рНopt. values of 7.2, rhizomes – 9-LOX (рНopt. 6.5). Peculiarities that were mentioned in localization and dynamics of LOX isoforms catalytic activity in the fern organs at various phases of development suggest that the enzyme might be involved in the regulation of lipid metabolism of growth processes that ensure plant adaptation to the environment.
<