Comparison of gas exchange and chlorophyll fluorescence of low-potassium-tolerant and -sensitive soybean [Glycine max (L.) Merr.] cultivars under low-potassium condition
The effects of potassium (K) deficiency on chlorophyll (Chl) content, photosynthetic gas exchange, and photosystem II (PSII) photochemistry during the seedling stage were investigated in two soybean [Glycine max (L.) Merr.] cultivars, low-K sensitive Tiefeng31 and low-K tolerant Shennong6. The cultivars were grown hydroponically in K-sufficient (KS) and K-deficient (KD) solutions. Photosynthetic gas exchange and Chl content in Tiefeng31 were severely affected by the low K condition, but were almost unaffected in Shennong6. This difference is in accordance with the PSII photochemistry in the plants, indicating that the photosynthetic apparatus of Shennong6 is more tolerant to low-K stress than that of Tiefeng31.
Additional key wordschlorophyll fluorescence low-K stress mesophyll resistance net photosynthetic rate stomatal conductance
the space above the fluorescence curve between F0 and Fm
intercellular CO2 concentration
maximal Chl fluorescence yield of dark-adapted state
minimal fluorescence yield of dark-adapted state
variable Chl fluorescence
maximal photochemical efficiency of PSII
stomatal conductance to water vapour
net photosynthetic rate
primary quinone acceptor of PSII
relative variable fluorescence intensity at the J-step
Unable to display preview. Download preview PDF.
This work is supported by a grant from Shenyang Agricultural University for young teachers (2006109) and the Creative Team Project (CTP) from the education department of Liaoning province.
- Hoagland, D.R., Arnon, D.I.: The water-culture method for growing plants without soil. — Agr. Exp. Stat. Circ. 347: 1938.Google Scholar
- Liu, G.D., Liu, G.L.: [A new strategy alleviation shortage of potassium resource in China.] — Sci. Agr. Sin. 28: 25–32, 1995. [In Chin.]Google Scholar
- Tang, J. C., Cao, M. J., Liu, X.: [Resistance mechanism and screening of soybean genotype resistance to low potassium.] — Soybean Sci. 22: 18–21, 2003. [In Chin.]Google Scholar
- Tiwari, K.N., Nigam, V., Pathak A.N.: Studies on the potassium requirements of different crops. — Nutr. Cycl. Agroecosyst. 8: 91–96, 1985.Google Scholar
- Wang, W., Cao, M. J., Zhou, C. X., Li, Z., Zhang, H.: [Screening of tolerance low potassium soybean varieties.] — Soybean Bull. 4: 7–8, 2005. [In Chin.]Google Scholar
- Wellburn, A.R.: The spectral determination of chlorophylls a and b, as well as total carotenoids, using various solvents with spectrophotometers of different resolution. — J. Plant Physiol. 144: 307–313, 1994.Google Scholar