Abstract:

P1ants of four wild Pr／mula species were planted in the field at Kunming and the photosynthesis
was tested with LI-6400 portable photosynthesis system for adding knowledge of photosynthesis to the wild
Pnm~a species．Species diference Was found in light compensation point(IJCP，txmol’m一’s )，light
saturation point(LSP，p,mol·m一。s )and CO2 compensation point(CCP，C02p,mol·mol )of photosynthesis．
Pr／mula pulverulenta Duthie had the highest LCP(28)，the other three species had lower LCP(8—1 5)．
P obconica Hance had both lOW I5P(80)and photosynthetic rate(Pn)，and highest CCP(80)．P bulleyana
Fort．and P．pulverulenta showed both the highest I5P(500)and Pn．and intermediate CCP(64—69)，while
P forrestii Balf．f．had middle LSP and Pn．but the lowest CCP(54)．The diurnal changes of Pn and transpi—
ration rate(Tr)in May were one．peaked curves．reaching a maximum at about 10 and 13 O’clock for Pn and
Tr．respectively．The species differences were exhibited by curve height of their diurnal courses

Key words: Primula, Photosynthesis, Compensation point, Saturation point, Photosynthetic rate