4种砧木对甜樱桃叶片光合特性的影响

Effects of Four Rootstocks on Photosynthetic Characteristics of Sweet Cherry

以‘马哈利’(Cerasus Mahale)’、‘考特’(Colt)、‘吉塞拉5号’(Gisela 5)和‘大青叶’(Cerasus pseudo Daqingye)4种砧木嫁接的6年生甜樱桃‘秦林’为试材,利用CIRAS-2型便携式光合作用系统,测定植株叶片的光响应曲线和光合日变化,探索砧木对甜樱桃叶片光合特性的影响。结果表明,4种砧木嫁接的‘秦林’甜樱桃的Pnmax为13.279~21.599μmol·m^(-2)·s^(-1),AQY为0.036~0.046,LCP为20.699~41.619μmol·m^(-2)·s^(-1)。‘秦林/考特’的Pnmax最高,相同弱光条件下其光合能力最大,‘秦林/大青叶’Pnmax最低。‘秦林/吉塞拉5’的LCP最低。4种砧木嫁接的‘秦林’甜樱桃净光合速率日变化均呈"双峰"曲线,有光合"午休"现象,且蒸腾速率(Tr)、气孔导度和羧化速率与之变化趋势一致;胞间CO2浓度(Ci)日变化大体呈‘U’字形趋势;一天中水分利用效率(WUE)呈现逐渐下降的趋势;强光下光合作用的降低主要是由气孔限制引起的。从光合日变化首峰值来看,‘秦林/考特’光合能力最强,‘秦林/大青叶’光合能力最弱,分别为18.07μmol·m^(-2)·s^(-1)和13.40μmol·m^(-2)·s^(-1)。

In order to learn the effects of different rootstocks on photosynthetic characteristics of sweet cherry,taking 6-year-old trees of Chelan as materials,which grafted with Cerasus Mahaleb,Colt,Gisela 5and Cerasus pseudo Daqingye as rootstocks,the light response curve and diurnal variation of photosynthetic physiological parameters were measured by CIRAS-2 portable photosynthesis system. The results indicated that the variations of maximum photosynthetic rate（ Pnmax）,apparent photosynthetic quantum yield（ AQY）and light compensation point（ LCP） were 13. 279 ~ 21. 599 μmol·m^（-2）·s^（-1）,0. 036 ~ 0. 046 and 20. 699 ~41. 619 μmol·m^（-2）·s^（-1）respectively. The Pnmaxof Chelan on Colt was the largest and showed the highest photosynthetic capacity under low intensity illumination,but the Pnmaxof Chelan on Daqingye was the minimum. Chelan on Gisela 5 showed the lowest LCP. The diurnal variation of Pn presented a double-peak distribution which means a midday depression occurred,while the transpiration rate（ Tr）,stomatal conductance（ Gs） and carboxylation efficiency（ CE） showed the similar trend. Diurnal variation of intercellular CO2concentration（ Ci） presented a U type distribution. The water utilization efficiency（ WUE） showed a gradual de-crease from 7 ∶ 00. Stomata limitation（ Ls） is the main reason for the decrease of photosynthetic rate under high intensity illumination. Learn from the first peak value of the diurnal variation of photosynthesis,the Pn of Chelan on Colt was the largest（ 18. 07 μmol · m^（-2）·s^（-1）） and Chelan on Daqingye was the lowest 13. 40μmol·m^（-2）·s^（-1）.