janell
I would like to speak with more individuals testing DMV to compare my observations with them, but the high view is the virus is not always present and the best time to test for a higher degree of (asymptomatic) accuracy is late fall.
The virus presents symptoms in times of stress, particularly when the evenings get cold (40's) or directly after a kiss of frost. During warmer times of growth (on a cutting mat or the middle of summer) the symptoms disappear. I suppose it may depend on the viral load of the plant and I need to look back over the testing data to see if that information can be extrapolated.
Testing asymptomatic plants can be a gamble with DMV which is 'good' and 'bad'. The good part is symptoms are easy to recognize if you train your eye and look for the new growth along the entire plant (even the low new shoots that can pop up late fall.) You wouldn't need to spend any money to have faith to cull the plant.
The bad is it makes virus indexing stock a longer more expensive process. I wouldn't trust a negative until it was negative two seasons in a row.
