Chilling temperature and photoperiod influence the timing of bud burst in juvenile Betula pubescens Ehrh. and Populus tremulaL. trees

Table 3 Univariate two-way ANOVA results for the timing of three stages of bud burst (first, 50 % and 100 % bud bursts) in species Betula pubescens and Populus tremula, in two different experiments with varying chilling durations (C; two conditions in experiment 1 and three conditions in experiment 2) and under different photoperiods (P; three conditions in experiment 1 and two conditions in experiment 2)

Effect	1st bud burst				50 % bud burst				100 % bud burst
	B. pubescens		P. tremula		B. pubescens		P. tremula		B. pubescens		P. tremula
	F (df)	p	F (df)	p	F (df)	p	F (df)	p	F (df)	p	F (df)	p
Experiment 1
C	0.37 (1)	0.547	1.97 (1)	0.174	1.33 (1)	0.261	–	–	10.12 (1)	0.004	–	–
P	0.21 (2)	0.808	0.76 (2)	0.481	3.86 (2)	0.036	0.03 (2)	0.973	5.30 (2)	0.013	0.71 (2)	0.52
C × P	0.05 (2)	0.955	0.34 (2)	0.716	1.74 (2)	0.199	–	–	4.62 (2)	0.021	–	–
Experiment 2
C	50.88 (1)	<0.001	86.6 (2)	<0.001	13.17 (1)	<0.001	211 (2)	<0.001	268 (2)	<0.001	7.83 (1)	0.009
P	13.83 (1)	0.001	0.03 (1)	0.855	0.02 (1)	0.901	6.05 (1)	0.018	18.45 (1)	<0.001	5.03 (1)	0.033
C × P	14.76 (1)	0.001	2.02 (1)	0.146	10.05 (1)	0.818	2.15 (1)	0.129	1.18 (1)	0.287	0.79 (1)	0.383

ISSN: 1297-966X