Comparative analysis of photosynthetic characteristics of male-sterile lines of Lilium
We studied the photosynthetic and physiological mechanisms of male-sterile Lilium. We selected a fertile line and a male-sterile line as materials. The LI-6400 system was used to measure photosynthetic and physiological parameters related to the photosynthetic efficiency of the leaves and to the environmental adaptability of Lilium. The main results were as follows. 1) Diurnal change in photosynthesis showed two peaks, at 11:00 and 14:00, for both the fertile and male-sterile lines, and the former was greater than the latter. This indicates that the photosynthetic midday depression of the leaves occurred at noon. 2) For both fertile and male-sterile lines, net photosynthetic rate (Pn) peaked (7.74 and 6.74 μmol m-2 s-1, respectively) at the bud stage, and produced the next highest values (6.22 and 5.01 μmol m-2 s-1, respectively) at the seedling stage. The lowest value (5.18 and 4.46 μmol m-2 s-1, respectively) of Pn appeared at the fruiting stage. In addition, throughout the growth and development period of Lilium, the Pn of the fertile line was higher than that of the male-sterile line. 3) Stomatal conductance (Cd), intercellular CO2 concentration (Ci) and transpiration rate (Tr) increased at first and then decreased, all parameters reaching maxima at the bub stage, but decreasing dramatically after the flowering stage. 4) During the growth and development period of Lilium, the light compensation point (LCP) initially decreased and then increased with growth. LCP peaked at the fruit stage and was lowest at the bud stage. The male-sterile line had a higher LCP than the fertile line. However, the light saturation point (LSP) presented a different behavior: it increased throughout the entire growth period of both the fertile line and the male-sterile line. 5) The male-sterile line showed a weaker photosynthetic capacity than the fertile line.
Jia, W.J., Cui, G.F., Ma, L.L., Duan, Q., Du, W.W., Wang, X.N., Zhao, P.F., Wang, J.H. and Mu, D. 2017. Comparative analysis of photosynthetic characteristics of male-sterile lines of Lilium. Acta Hort. (ISHS) 1171:111-118
lily, male-sterility, photosynthesis, chlorophyll, midday-depression, light response