This week was a bit of a waiting game: we waited until later into the week for the fungi isolated last Friday to start to grow so we could evaluate what we collected. In the meantime, Beth and I collected a few more leaf/fungal samples, sterilized them, and did a few more isolations.
So on Wednesday I checked up on my plates, and what I saw made me wish I hadn’t. There was bacterial contamination, as well as contamination by other fungi on most plates, and a few colonies that looked like they could have been G. bidwellii if you squinted at them right, but probably weren’t.
Beth tells me that the initial isolations always look this bad, but I nonetheless felt a little disheartened. I hoped that the isolations we did the day before turned out a bit better.
We were also waiting this week for the inoculated V. rupestris B38 x ‘Horizon’ population to start to show symptoms of infection. Infection starts to become visible at 11 to 16 days, and having inoculated on June 16, we were expecting to see symptoms any day now.
We were disappointed. On Thursday July 2, now 16 days post inoculation, we scoured the block for symptoms and found only one diseased vine, probably the result of an earlier infection and the product of naturally-occurring inoculum. We started to speculate as to what could have gone wrong–could the inoculum not have taken to the plants, for one reason or another, or was it just delayed by the cooler-than-average weather? Only time would tell, and we just prayed to the science gods that when we checked again on Monday there would be disease.
This week was one of those unfulfilling weeks where nothing seems to go your way. If only G. bidwellii would grow this poorly in commercial vineyards, we could all go home early instead of sitting around scratching our heads 😉
To come: updates on what became of the fungi. Stay tuned!