engleski

Trendline analysis in biological processes during the proliferation of spruce vegetative buds into young needles

Background and Purpose: Biological processes inherently include time as a variable component.The characteristic of developmental processes are quantitative changes in biochemical and structural parameters. The dynamics of these changes can follow some regular pattern that can be described using appropriate mathematical function. Therefore the results of four groups of data obtained by different quantitative measurements of Picea abies and Picea pungens buds or needles were used as a substrate to be evaluated with trendline calculations. Materials and methods: The annual dynamics of photosynthetic pigment concentrations in vegetative buds proliferating into shoots with young needles and in one-year old needles, the amount of total soluble proteins in vegetative buds and after bud break in young needles, the area of embryonic shoot inside covered vegetative buds immediately before bud break, and the mitotic activity were tested. Regression analysis was performed by comparing experimentally obtained results with the best fitting mathematical functions for each group of data. Associated trendlines were constructed and fitness was expressed as coefficieant of determination (R2), which was further tested for probability (P). Results: All presented processes connected with proliferation of vegetative buds into shoots bearing young needles showed better fitting with polynomial trendlines than with any other function. Described changes had different rate compared on the basis of equal time portion. When a portion of time, including well-defined changes, was selected, significant fitting with polynomial trendlines of the second order was obtained. The intention to attach polynomial trendlines to the data obtained by measurements during a prolonged period was successful and R2 was sufficient when a higher order of polynomial trendline was chosen. Conclusions: Taking physiological processes as a basis for investigated changes is necessary for eventual prognoses of tendency and modelling of events. Insufficiently critical approach can lead to wrong prognoses, while appropriate application of trendlines can give valuble results, especially when investigations are done at different periods and the comparison of obtained data is required, as it is in this paper.

Picea; vegetative buds; shoot development; trendline analysis

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