新红星与红星苹果幼树光合特性研究

采用红外线 CO_2气体分析仪、改良半叶法对新红星、红星苹果幼树新梢叶片光合特性进行比较研究,结果表明:两个品种幼树新梢叶片光合强度季节变化、日变化规律相似,均呈双峰曲线,其中日变化“午休”现象明显。年周期和日周期中,新红星苹果幼树新梢叶片的光合强度均显著地高于红星苹果幼树。与红星苹果幼树相比,新红星苹果幼树具有较高的光饱和点和较低的光补偿点,光能利用率高。整个新梢不同叶位叶片的光合强度,新红星苹果幼树均高于红星苹果幼树。与红星苹果幼树相比,新红星苹果幼树呼吸强度低、呼吸消耗少、光合强度高,能够积累较多的光合产物,有利于早果、丰产。

Studies on the Photosynthetic Properties of Young Red Delicious and Starkrimson Apple Trees

The photosynthetic properties of leaves on shoots of young apple trees between Red De-licious and Starkrimson are compared with infrared gas analyser and improved half—leafmethod.Results showed that the seasonal and daily photoperiod variations of the two vari-eties show similar patterns of double—peak curves and obvious“noon nap”in daily varia-tion.Both annual and daily photosynthetic rates of Starkrimson are much higher togetherwith higher saturation point and lower compensation point or higher light energy conversionthan that of the Red Delicious.The Starkrimson is superior to Red Delicious for its higherphotosynthetic rate,lower respiratory rate and lower consumption by respiration which re-sult in its higher photosynthetic accumulation,fruiting at early ages and high yield.