Needle Rusts of Conifers

Needle rusts of conifers Common name Needle rust of conifers Causal agent Needle rust of conifers is caused by a fungus belonging to the genus coleosporium. It requires two hosts to complete its life cycle, a pine tree and a plant from the aster family. Scientific name Coleosporium asterum Symptoms & Signs Th needles turn yellow due to orange and yellow spots and bands on the foliage. Tiny, raised white tubes are also present on the needles that produce spores. In case of severe infection, th needles turn brown and fall off early. In the aster family, the upper side of the leaves shows yellow spots, while the lower side has orange pustules. Transmission The wind transfers the spores to other healthy plants of the opposite family to continue their life cycle. Time of concern Early spring to late fall Common hosts Austrian pine Jackpine Red pine Aster Goldenrod Gumweed