Seasonal variations of auxin and gibberellin A4 levels in cambial-region tissues of three conifers (Pinus elliottii, Chamaecyparis obtusa, and Cryptomeria japonica) with inherently different wood densities

Journal of Wood Science

Official Journal of the Japan Wood Research Society

Table 2 Characteristics of annual ring formation and plant hormones among three conifer species

Species	n	Number of tracheids formed			IAA (ng/cm²)			GA4 (ng/cm²)
Species	n	E	L	p	E	L	p	E	L	p
Sugi	4	24(15)	14(9)	0.07	52.2(16.8)	31.3(7.8)	0.001	1.9(1.9)	0.8(0.4)	0.06
Hinoki	4	6(6)	10(8)	0.24	37.9(12.5)	36.5(13.1)	0.81	1.0(0.5)	1.8(2.4)	0.38
Slash pine	3	9(9)	20(9)	0.04	101.3(37.5)	126.4(55.8)	0.36	1.2(0.4)	1.6(1.2)	0.46

E early season, L late season, p p-value of t test
The significant difference between E and L was examined by t test
The numbers of tracheids formed in E are the means for each species in test periods I and V
The numbers of tracheids formed in Lare the means fore ach species in test periods II–V
TheIAA and GA4 data in E are the means for each species in Mayandthe following April
The IAA and GA4 data in L are the means foreach species in July–November
Data in parentheses are standard deviations