Table 2.

Two-way ANOVA of the effect of drought stress intensities (df = 3) and drought stress duration (df = 3), and their interactions on xylem anatomical properties of 1-year-old Chinese fir seedlings.

Plant organ and property	Drought stress intensity		Drought stress duration		Drought stress intensity × Drought stress duration
	F	P	F	P	F	P
Root
Tracheid density	2.070	0.117	15.568	< 0.001***	4.190	< 0.001***
Tracheid diameter	50.911	< 0.001***	97.312	< 0.001***	8.263	< 0.001***
Pit density	30.883	< 0.001***	83.399	< 0.001***	3.756	0.001***
Pit membrane diameter	1.566	0.210	9.376	< 0.001***	3.898	0.001***
Pit aperture diameter	1.159	0.335	1.548	0.214	5.117	< 0.001***
Pit open ratio	1.974	0.130	2.132	0.108	0.971	0.476
Stem
Tracheid density	77.058	< 0.001***	116.366	< 0.001***	8.682	< 0.001***
Tracheid diameter	132.621	< 0.001***	187.350	< 0.001***	34.860	< 0.001***
Pit density	77.904	< 0.001***	70.666	< 0.001***	15.214	< 0.001***
Pit membrane diameter	12.764	< 0.001***	5.362	0.003**	5.366	< 0.001***
Pit aperture diameter	13.180	< 0.001***	5.674	0.002**	2.879	0.008**
Pit open ratio	18.081	< 0.001***	6.678	0.001**	4.268	< 0.001***
Branch
Tracheid density	62.361	< 0.001***	40.946	< 0.001***	13.166	< 0.001***
Tracheid diameter	31.230	< 0.001***	17.901	< 0.001***	5.327	< 0.001***
Pit density	34.141	< 0.001***	22.098	< 0.001***	7.732	< 0.001***
Pit membrane diameter	25.742	< 0.001***	19.839	< 0.001***	19.127	< 0.001***
Pit aperture diameter	32.569	< 0.001***	15.935	< 0.001***	17.269	< 0.001***
Pit open ratio	17.885	< 0.001***	0.361	0.781	6.463	< 0.001***

**significant at P < 0.01; ***significant at P < 0.001.