000			01676nam a2200205Ia 4500
008			220216s9999 xx 000 0 und d
100			_aRay D
245		0	_aSignificance of the leaf area ratio in Hevea brasiliensis under high irradiance and low temperature stress
260			_bPhotosynthetica _c2004
300			_a93-97
520			_aAdjustment in leaf area : mass ratio called leaf area ratio (LAR) is one of the strategies to optimize photon harvesting. LAR was recorded for 10 genotypes of Hevea brasiliensis under high irradiance and low temperature and the genotypes were categorized into two groups, i.e. high LAR and low LAR types. Simultaneously, the growth during summer as well as winter periods, photosynthetic characteristics, and in-vitro oxidative damage were studied. Low LAR (19.86+_0.52 m2 kg -1) types, recorded an average of 18.0;chlorophyll (Chl) degradation under high irradiance and 7.1;Chl degradation under low temperature. These genotypes maintained significantly higher net photosynthetic rate (PN) of 10.4 Mmol(CO2)m-2 s-1 during winter season. On the contrary, the ihgh LAR (24.33+_0.27 m2 kg-1) types recorded significantly lower PN of 4 Mmol(CO2) m-2 s-1 and greater Chl degradation of 37.7 and 13.9;under high irradiance and low temperature stress, respectively. Thus LAR may be one of the physiological traits, which are possibly involved in plant acclimation process under both stresses studied.
650			_aLeaf area ratio
650			_aLow temperature stress
650			_aNet photosynthetic rate
650			_aPhoto-oxidative damage
650			_aStomatal conductance
700			_aDas G
700			_aDey S K
942			_cJS
999			_c68686 _d68686