Model study on gas exchange and diffusion in legume nodules

Abstract

Abstract: Amodel is introduced to simulate the gas exchange and dirrusion in legume nodules with the aim of elucidating some aspects of regulating low O₂ concentration in the infected cells of nodules. Both of Layzell-Hunt and Bergersen-Sheehy Models suggested that the diffusion barrier is aqueous and may ccnsist of a layer cf cells in the nodule cortex,in which,the intercellular spaces are filled with water. The resistance of such a barrier could be regulated by altering the depth of water occupying the intercellular spaces. The advantage of the model is an inherent flexibility,so that having obtained a first approximation to this extreme complex symbiotie association,and evaluated this approximation in the light of empirical or theoretical consideration. The model should be modified in lectifying in its assumption.

Key words: Legume nodule, Gas exchange, Diffusion barrier, Fick's1st and2nd laws, Intercellular spaces

Lin Jishang, Wang Shujin, Hu Jisheng. Model study on gas exchange and diffusion in legume nodules[J]. Chinese Journal of Applied Ecology, 1990, 1(4): 364-372.

References

[1] Bergersea, F.J. 1982.Root Nodules of Legumes.Structure and Functions. Research Studies Press, Toronto.

[2] Dixoa. R.O., Blunders. E.A., and 5ear1. J.W.1981.Intercellular space and hydrogen , diffusion is peaand lupinrootnodules.PlantScience Letters. 23:109-116.

[3] Dixon. R.O. and Wheeler. C.T. 1987.Nitrogen Fixation in Plants.Blackie, Glasgow and London, 61-86.

[4] Duraad. J.L., Sheehy. J.E. and Minchia. F.R.1981.Nitrogenaseactivity, photosynthesis and nodule water potential is soybeanplants experi-eaciagwaterdeprivatioa. J.Exp.Bot., 38:311-321.

[5] Huat. S., King. B.J. and Canvin. D. T.1987.Steady and nonsteady state gas exchange characteristics ofsoybeannodulesin relation to the oxygen diffusion barrier. Plant Physiol., 84:164-172.

[6] Hunt. S., Gaito. S.T. and Layzell. D.B. 1988.Model of gas exchange anddiffusionislegume nodules.(I)Characterizationofthediffusion barrierandestimation of CO₂, H₂ and N₂ is the 173:128-141.

[7] the concentration of infectedcell.Plants, S.T, and Hunt. 5.1988 and the 117-127.

[8] Lin. J., i gas exchange anddiffusionislegume (j)Calculation ofgasexchange rate:energy cost of Na fixation. Plants. 173"Canvin. D.T. sad Layzell. D.B. l988, Structural and physiological basesforeffectivity of soybean nodules formedbyfast-and slow-growing bacteria. Can. J. Bot., 66 :526-534.

[9] Minchin. F.R, , Sheehy. J.E, sadWitty. J.F, 1985. Characterizationofthe resistance toOs diffusion is legume nodules. Ann. Bot, , 55:53-60.

[10] vanNoordwij] c. M. and de Willigen, P, 1984, Mathematical models ondiffusiono foxygen to and within plant roots. with special emphasis on effects of soil-root contact, (I)Applicatioas.Plant and Soil. 77:215-241.

[11] Ralston. E.J. and Ismande, 1, l9sz, Entry of oxygen and nitrogen into intact Soybean nodules, 1. Exp. Bot, , 33: 208-214,

[12] Sheehy. 1.E., Bergersen. F.Rr and Witty. J.F.1987. A simulation study of gaseous diffusion resistaace, 'aodules pressure gradients and biological nitrogen fixation in soybean nodules. Ana. Bot, , 60: 345-351.

[13] Sheehy. J.E., Minchia. F.R. andWitty, J.F.1983.Biological control of the resistance to oxygen flux in nodules. Ann. Bot., 52: 665-571.

[14] Sinclair. T.R, and Goudriaan. J. 1981.Physical and morphological constraints on transport in nodules. Plant Physiol., 61:143-145.

[15] Stewart, W.D. (ed.).1975. Nitrogen Fixation by Free-livingMicroorganisms.CambridgeUniv, Press. London. 3-28.

[16] Torrey, J.G., Winship. L.J. (eds.).1989. Applicatioas of Continous and Steady-state Methods to Root Biology. Kluwer Academy Publisher, Dordrechi, 97-119.

[17] Vessey. J.K., Walsh. K.B.and Layzell, D.B.1988. Oxygen limitation of Nxfixationinstem girdled and nitrated soybean. Physiol. Plant. 73:113-121.

[18] Walsh. K.B., Vessey. J.K. and Layzell. D.B.1987.Carbohydrate supplyandNxfixation in soybean.The effect of varied daylenght and stem girdling. Plant Physiol.. 85:137-144.

[19] Weisz. P.R. and Siaclair. T.R.1987. Regulation of soybean nitrogen fixation in response to rhizophere oxygen.(I)Role of nodulerespiration, (I)Quantificationofnodule gas permeability.Plant Physiol., 85:900-910.