Gas Exchange and Productivity in Temperate and Droughty Years of Four Eastern, Elite Loblolly Pine Genotypes Grown in the Western Gulf Region

Table 4

Crown foliage area (m²), light-saturated photosynthesis (µmol·m⁻²), conductance (mmol·s⁻¹), and transpiration (mmol·s⁻¹) of previous-year and current-year foliage of loblolly pine genotypes at a site in North Central Louisiana in August 2009 and in 2010 (averaged for May, June, August, and September).

	Previous-year foliage				Current-year foliage
	HS756	HS8103	V9	V93	HS756	HS8103	V9	V93
Foliage area
August 2009	13.81^a	3.11^b	4.50^b	13.37^a	28.82^a	9.72^b	9.79^b	23.24^a
May–September average 2010	77.57^a	38.52^b	57.44^a	26.28^c	169.85^a	41.66^b	139.30^a	30.43^b
Photosynthesis
August 2009	81.41^a	18.00^b	23.35^b	80.46^a	183.10^a	57.70^b	59.10^b	145.54^a
May–September average 2010	59.43^a	17.35^ab	51.71^a	8.81^b	100.66^a	30.44^ab	116.10^a	11.80^b
Conductance
August 2009	1.09^a	0.20^b	0.26^b	1.11^a	2.55^a	0.67^c	0.67^c	1.41^b
May–September average 2010	0.88^a	0.44^bc	0.71^ab	0.29^c	1.93^a	0.42^b	1.67^a	0.27^b

For each parameter, date, and foliage flush, means within a row followed by different letters are different at .