Update on Blister Rust Resistant White Pine

An article in the August l996 issue of this Newsletter described the efforts by several biologists to develop blister rust resistant white pines.

The current research of Dr. Paul Zambino at the Forest Biotechnology unit of the North Central Forest Experiment Station, in Rhinelander, Wisconsin is aimed at speeding methods of screening seedlings for resistance. His present studies show that inoculation of pine seedlings (as young as five months old) allows observations of disease symptoms on needles and stems within a year. Size of spots on needles and slow progress of cankers on stems are studied for evidence of seedling resistance to the disease. Screening for resistance to only some or all of the strains of the rust fungus is another part of Dr. Zambino's research.

Dr. Paula Pijut, at the North Central Forest Experiment Station in St. Paul, is testing the effects plant hormones on young white pines in order to stimulate early flowering of pollen flowers. If successful, this will bring white pine seed orchards into earlier seed production and speed release of "improved" white pine seed.

Dr. Mike Ostry, a forest pathologist at the North Central Forest Experiment Station in St. Paul, is teaming up with Superior National Forest and Northeastern Area-State and Private Forestry to study best management practices for silvicultural control of blister rust in artificially regenerated white pine.

Achieving the goal of blister rust resistant white pine is difficult and will require the continued efforts of many biologists for several years.