Balancing photosynthetic light-harvesting and light-utilization capacities in potato leaf tissue during acclimation to different growth temperatures.
We investigated the effect of temperature during growth and development on the relationship between light-harvesting capacity, indicated by chlorophyll concentration, and light-utilization potential, indicated by light- and bicarbonate-saturated photosynthetic oxygen evolution, in Solanum tuberosum L. cv. Norland.  Clonal plantlets were transplanted and grown at 20 degrees C for 2 weeks before transfer to 12, 16, 20, 24 and 28 degrees C for 6 weeks.  After 4 weeks of the temperature treatments, leaf tissue fresh weights per area were one-third higher in plants grown at 12 degrees C vs those grown at 28 degrees C.  Conversely, chlorophyll content per area in tissue grown at 12 degrees C was less than one-half of that of tissue grown at 28 degrees C at 4 weeks.  Photosynthetic capacity measured at a common temperature of 20 degrees C and expressed on a chlorophyll basis was inversely proportional to growth temperature.  Leaf tissue from plants grown at 12 degrees C for 4 weeks had photosynthetic rates that were 3-fold higher on a chlorophyll basis than comparable tissue from plants grown at 28 degrees C.  These results suggest that the relationship between light-harvesting capacity and light-utilization potential varies 3-fold in response to the growth temperatures examined.  The role of this response in avoidance of photoinhibition is discussed.
Steffen
K L
KL
Dept of Horticulture, Pennsylvania State Univ., University Park 16801, USA.
Wheeler
R M
RM
Arora
R
R
Palta
J P
JP
Tibbitts
T W
TW
D000064:Acclimatization / Q000502:physiology*; D002734:Chlorophyll / Q000378:metabolism*; D008027:Light; D010100:Oxygen / Q000378:metabolism; D017440:Photoperiod; D010788:Photosynthesis / Q000502:physiology* / Q000528:radiation effects; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D011198:Solanum tuberosum / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D013696:Temperature
D002734:Chlorophyll; D010100:Oxygen