Gender- and season-related variability in the content of proteins, amino acids, and carbohydrates in Taxus baccata needles of different age

Abstract

The present study aimed to determine if the needles of male and female European yew (Taxus baccata L.) trees differ in their content of basic compounds (proteins, amino acids, and carbohydrates), and whether the observed differences result only from the gender factor or if they are also associated with the needles' age and season. The study was conducted on male and female European yew specimens, collected from the Botanical Garden of the Jagiellonian University in Krakow during three seasons. Male specimens had significantly higher content of insoluble carbohydrates compared to the females ones. In the first year of the needles life, the dry mass and content of soluble carbohydrates increased significantly. In the third year of the needles' life, the content of amino acids increased significantly and the content of soluble proteins decreased. The highest differences between the genders in the individual months were observed in the soluble carbohydrates and amino acids amounts and the least in the soluble proteins. The growth of the new needles seems to be at least partly sustained by carbohydrates remobilization from the older needles. In conclusion, male and female yews differ in their metabolism. These gender differences may vary with the needles' age. For this reason, the needle samples of different age should not be mixed, and the sampling time should be chosen carefully. For one-year-old needles, a potentially interesting gender marker may be an increased content of free amino acids in June and July, and high content of soluble carbohydrates in January, while for two-year-old needles, an increased content of free amino acids in male individuals from September. March seems to be an interesting month, as it shows significant differences between the genders in terms of all biochemical features studied in this research.