Page 184 - PC2019 Program & Proceedings

PLANT CANADA 2019

S153 Evaluating seed treatments for the management of soybean cyst nematode (Heterodera
glycines Ichinohe) in dry bean (Phaseolus vulgaris L.).
2
1
*1
Katsande, T. ; K. Jordan ; A. Schaafsma ; C. Trueman ; C. Gillard 2
2
2
1 University of Guelph; University of Guelph - Ridgetown Campus

Dry bean is a high value crop grown worldwide. Canada is the fourth largest dry bean exporter, making it
a producer of global importance. Soybean cyst nematode (SCN) infestation is a major cause of yield loss
in soybean (Glycine max (L.) Merr.), and dry bean is an alternate host. In soybean, genetic resistance is
the primary source for SCN control however there are no management measures currently available in dry
bean. Seed treatments for soybean, including BAS576AAS, BAS79800F, BAS97474F, Bacillus
amyloliquefaciens, Pasteuria nishizawae, Bacillus firmus and fluopyram were assessed for effects on
SCN populations in black (cv. Zorro) and kidney (cv. Dynasty; Red Hawk) bean. Two field studies were
conducted in 2018 on naturally infested soils near Highgate and Rodney, ON. In addition, two different
growth cabinet studies, each repeated once, were completed. There was little treatment response in the
field studies. In the first growth cabinet study, B. amyloliquefaciens and B. firmus reduced cysts by 24%
and 10% in black bean and by 25% and 24% in kidney bean, respectively, while fluopyram only reduced
cysts in Red Hawk by 25%. In the second study, fluopyram reduced cysts by 49% and 87% in Dynasty
and Red Hawk, respectively while the other treatments had less effect. Results provide a better
understanding of potential SCN management options for dry bean production in Ontario.

Trust Katsande (tkatsand@uoguelph.ca)

S154. Red alder defense mechanisms against western tent caterpillar defoliation
1
*1
1
Boateng, K. ; B. Hawkins ; P. Constabel ; A. Yanchuk
2
1 University of Victoria;
2 BC Ministry of Forests, Lands, Natural Resource Operations and Rural Development
Red alder (Alnus rubra) is a tree species with high economic and ecological importance. It is subject to
defoliation during unpredictable, episodic outbreaks of tent caterpillars (Malacosoma spp.) that result in
reduced growth and mortality in severe cases. To identify A. rubra families or individuals that may be
resistant to tent caterpillars, we evaluated the variation in tent caterpillar resistance among and within red
alder populations, and investigated defense mechanisms of red alder against tent caterpillars. Bioassay
feeding trials were conducted with western tent caterpillars (WTC) (Malacosoma californicum) on twenty
red alder clones from ten provenances. Phenology and quality of red alder leaves as food for the
defoliators were analyzed to determine if budburst, leaf chemical content, or physical traits are major
determinants of WTC preference for red alder leaves. Seasonal variations in concentrations of oregonin
and total phenolics in red alder leaves, and induction of these compounds in response to wounding were
examined. Alder clones differed in percentage leaf area eaten by caterpillars and in leaf defense traits. The
concentrations of foliar phenolic compounds negatively correlated with the percentage leaf area eaten by
the caterpillars. Particularly, oregonin concentration above 20 % leaf dry weight consistently appeared to
reduce feeding by caterpillars. The concentration of oregonin varied during the growing season and there
were no significant responses of any of the measured compounds to wounding.

Kennedy Boateng (boatengk@uvic.ca)

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