A Zoospore Inoculation Method with Phytophthora sojae to Assess the Prophylactic Role of Silicon on Soybean Cultivars

作者：Guerin Valerie; Lebreton Amandine; Cogliati Erik E; Hartley Sue E; Belzile Francois; Menzies James G; Belanger Richard R^*

来源：Plant Disease, 2014, 98(12): 1632-1638.

DOI：10.1094/PDIS-01-14-0102-RE

The objective of this study was to evaluate whether silicon (Si) amendments, known to have a prophylactic role against biotrophic and hemibiotrophic pathogens, could protect soybean against Phytophthora sojae. To fulfill this objective, the initial challenge was to develop a method of inoculation that reproduced the natural infection process while allowing regular Si feeding to the plants. In a first set of experiments, inoculation of P sojae zoospores directly into hydroponic solutions led to reproducible infections and expected phenotypes when using %26apos;Williams%26apos; (rps), %26apos;L75-6141%26apos; (Rpsla), %26apos;haro15%26apos; (Rps1k), and %26apos;L77-1863%26apos; (Rps1b) soybean challenged to races 3 and 7 of P. sojae. This approach offers the advantage of testing simultaneously many soybean cultivars against different races of P sojae in a controlled environment, and the expression of partial and root resistance. In a second set of experiments aimed at testing the effect of Si, our results clearly showed that Si amendments had a significant effect on disease reduction and plant yield. The effect was particularly noticeable when combined with a cultivar displaying a certain level of resistance to the disease. These results demonstrate a useful method of direct inoculation of soybean plants with P sojae zoospores through a hydroponic system and show that Si amendments can represent an alternative method of control of P sojae against soybean.

• 出版日期2014-12