Development of a growth chamber screen for purple spot resistance in asparagus spears

Multiple experiments were conducted to develop a growth chamber screen for resistance to purple spot which correlated with field disease severity. Experiments included: (1) quantification of cultivar differences to infection under natural field conditions, (2) quantification of cultivar difference of inoculated spears in the growth chamber when spears were standing in 0, 5 and 10% sucrose, and (3) quantification of spear glucose, fructose and sucrose levels in the field and spears incubated in a growth chamber for 3 and 7 days.