Table 3.

Mean (±SE) concentration of prunasin in roots expressed per root dry mass of Prunus serotina seedlings in function of time, light treatments, combinations of seedlings, and mulching, and interactions. The different letters indicate that the mean values are significantly different in Tukey’s a posteriori test at α = 0.05 (α – level of significance). DOY – day of year, LL - low light (10 %), ML - medium light (25 %), HL - high light (100 %), P – three P. serotina seedlings (monoculture), Q + P + L – three Quercus petraea + six P. serotina + mulching with P. serotina leaves

Effects		N	Mean ± SE (mg g−1 DM)
Control	May	9	3.45 ± 0.52
Time of sampling	June (DOY 176)	34	19.95 ± 2.12	a
	August (DOY 238)	36	39.50 ± 3.85	b
	September (DOY 269)	36	18.51 ± 4.90	a
Light	LL	36	30.33 ± 4.37	a
	ML	34	27.52 ± 4.41	ab
	HL	36	20.50 ± 4.41	b
Competition	P	52	26.02 ± 3.88
	Q + P + L	54	26.18 ± 3.42
Time of sampling × light	176 × LL	12	16.68 ± 4.24	a
	176 × ML	10	26.51 ± 3.10	a
	176 × HL	12	17.74 ± 2.42	a
	238 × LL	12	32.79 ± 6.60	a
	238 × ML	12	45.45 ± 5.98	a
	238 × HL	12	40.25 ± 7.43	a
	269 × LL	12	41.53 ± 8.36	a
	269 × ML	12	10.42 ± 3.28	b
	269 × HL	12	3.57 ± 0.73	b
Time of sampling × competition	177 × P	16	21.28 ± 3.38
	177 × Q + P + L	18	18.77 ± 2.77
	238 × P	18	36.60 ± 6.32
	238 × Q + P + L	18	42.40 ± 4.57
	269 × P	18	19.65 ± 8.10
	269 × Q + P + L	18	17.37 ± 6.01
Light × competition	LL × P	18	30.02 ± 6.57
	LL × Q + P + L	18	30.65 ± 6.17
	ML × P	16	24.66 ± 7.64
	ML × Q + P + L	18	30.06 ± 5.12
	HL × P	18	23.23 ± 6.65
	HL × Q + P + L	18	17.82 ± 6.06