The influence of pine twist rust (Melampsora pinitorqua) on growth and development of Scots pine (Pinus sylvestris)

Abstract

Abstract The influence of pine twist must ( Alelampsora pinitorqsat ) on growth and development of Scots pine was studied during three consecutive years. The experimental material included three provenances from natural stands and one open pollinated seed orchrd progeny. Trees severely affected by pine twist must reached an average of 38% lower height than did not‐affected trees. while mildly affected trees grew somewhat better, on the average, than did non‐affected trees. Pine twist must caused tha greatest loss of height increment in the seed orchard progeny.