Galina Vasilyeva, Evgeniya Zhuk
Needle structure of mutational witches’ brooms in Pinus sibirica
Dendrobiology 2016, vol. 75: 79-85
Mutational witches’ brooms (WBs) in conifers are widely used in landscaping. However, there have been few WB morphology and anatomy investigations. The needle structure of witches’ brooms and normal crown (NC) in Pinus sibirica clones was studied, using light microscopy technique. The aim was to compare the needle structure in WBs and NC and to reveal the effects of the mutation on the needle traits. Three WB and NC pairs of clones from the same trees were used in the study. WBs in the parental trees were characterized by different density in the affected part of the tree. In all pairs, WB needles were shorter and thinner than in NC. In contrast to NC needles, WB needle length was positively correlated with resin duct total area and width of endodermis cell. Thus, the affected needles had a changed structure, and the effect of the mutation was determined by mutation expression.
Keywords: needle anatomy, plant variation, dwarf conifer, clones, Siberian stone pine