Table III.

Enzyme activities and lignin deposition after 24, 48, 72, and 96 h of exposure to C. magna wild-type L2.5 in susceptible cucurbit plant varieties

Variety	Peroxidase Activity				PAL Activity				Lignin Deposition
	24	48	72	96	24	48	72	96	24	48	72	96
	A min−1 ug−1 protein				A min−1 protein
Sugar Baby (−)a	2.76	3.46	4.62	5.34	2.27	2.90	2.50	2.6	−	+	++	+++
Sugar Baby (+)b	5.77	6.30	NDc	ND	2.50	3.70	ND	ND	+++	++++	*d	*
Marketmore (−)	0.63	1.31	1.9	2.1	0.02	0.25	0.11	0.17	−	+	++	+++
Marketmore (+)	1.8	2.34	ND	ND	0.27	0.34	ND	ND	+++	++++	*	*

Peroxidase activity, PAL activity, and lignin deposition on anthracnose-susceptible cultivars after exposure to the wild-type L2.5 isolate. The data presented were obtained from 30 cucurbit seedling stems of similar size and age and were processed as required for each assay. Peroxidase activity was monitored as a change in A₄₇₀. PAL activity was monitored at 290 nm. Lignin deposition was measured on a qualitative basis and ranged from absent (−), basal (+), low (++), moderate (+++), to moderately high (++++) levels.

^a–, Not colonized with the path-1 mutant. 

^b+, Colonized with the path-1 mutant; path-1 colonized mutants were assessed for 48 h prior to exposure to the wild type (data not shown) and for an additional 48 h post challenge. 

^cND, No data. 

^dStatistical analysis (ANOVA) revealed statistically significant differences (P < 0.05) in the treatments among time points in all assays for both cultivars, with the exception of PAL activity (P > 0.05) in the Marketmore cucumber variety.