Effect of drought on variability of cones and seeds of Pinus sylvestris L.

One of the adverse effects of global warming is the growing threat of drought. Periods of water deficit together with high temperatures are the main abiotic stresses negatively affecting the function of plants. The projections of climate change indicate an increase in temperature and a decrease in precipitation in the future. The predicted increase in the intensity and frequency of droughts is supposed to have negative effect on physiological and physical characteristics of seeds of forest trees. This study aims to determine the impact of the 2015 drought on the phenotypic characteristics of cones and seeds from Scots pine orchards located in western Poland. Five clonal seed orchards, each composed from plus???trees representing one Scots pine provenance, were included in the study. Collected material provided data about the length and width of cones and seeds, as well as the frequency of full and empty seeds per cone. Analyses indicated a signifi??? cant impact of drought on the biometric characteristics of the seeds, which were generally smaller. Dimensions of cones were not affected, but mass of cones grown during drought was slightly lower. The number of seeds in cone ripened during the drought was lower, but the relative number of empty seeds was not affected. Generally, provenances represented by plus???trees were not differentiating average values of analysed variables.