日本落叶松与长白落叶松及其杂种光合特性比较

以采穗圃中的采穗母株为研究对象，对日本落叶松、长白落叶松及其杂种进行了光响应曲线和CO2响应曲线的测定，通过估算光合参数，比较了它们的光合特性。结果表明:与日本落叶松相比，日本落叶松×长白落叶松杂种的最大净光合速率、表观量子效率和光合能力等与光合效率正相关的参数都较低，光强和CO2的利用范围也更窄，暗呼吸速率却更高，而羧化效率和光呼吸速率没有差别。与长白落叶松相比，尽管长白落叶松×日本落叶松杂种的暗呼吸速率较低，但其表观量子效率更低，CO2补偿点更高，而羧化效率、光呼吸速率、光补偿点没有差别。日本落叶松×长白落叶松杂种与长白落叶松×日本落叶松杂种相比，光呼吸速率和CO2补偿点稍高，羧化效率稍低，而表观量子效率、暗呼吸速率、光补偿点没有差别。因此，认为落叶松杂种的光合效率不具有超亲杂种优势。 

Comparison in photosynthetic characteristics of Larix kaempferi, L. olgensis and their hybrids

Photosynthetic parameters calculated from light-response curves and CO2-response curves were compared among Larix kaempferi,L.olgensis and their hybrids grown in a cutting orchard to compare their photosynthetic characteristics.The results showed that compared with L.kaempferi,L.kaempferi×L.olgensis had lower Pmax (maximum net photosynthetic rate),AQY (apparent quantum yield),Pm (photosynthetic capacity) and higher Rd (dark respiration rate) and thinner usable range in light quantum and CO2 concentration,while no differences were observed in CE (carboxylation efficiency) and Rp (photorespiratory rate) between the two taxa.L.olgensis×L.kaempferi had lower AQY and Rd but higher Г (compensation point) relative to L.olgensis,while their CE,Rp and LCP (light compensation point) exhibited no differences.Compared with L.olgensis×L.kaempferi,L.kaempferi×L.olgensis had higher Rp and Г but lower CE,while no differences were observed in AQY,Rd,and LCP between the two taxa.In conclusion,our findings show that larch hybrids’ photosynthetic efficiency does not exhibit super parent heterosis.