Document Type : Research Paper
Authors
Abstract
The rhizosphere is a microecological zone in direct proximity of plant roots. The theoretical extent of the rhizosphere is dependent on the zone of influence of the plant roots and associated microorganisms. The rhizosphere is a metabolically busier, faster moving, more competitive environment than the surrounding soil. The rhizosphere include three zones which are defined based on their relative proximity to and thus influence from the root: Endorhizosphere,Rhizoplane and Ectorhizosphere. The rhizodeposites include: Root Exudates, Secretion, Lysates and Gaseous Compounds. Compounds in root exudates assist plants in accessing nutrients by acidifying or changing the redox condition within the rhizosphere or directly chelating with the nutrient. As the soil dries and its hydraulic potential decrease, exudates will subsequently begin to lose water to soil. When this occurs, the surface tension of the exudates decreases and its viscosity increases. In addition, as viscosity increase, the resistance to movement of soil particles in contact with exudates will increase, and a degree of stabilization within the rhizosphere will be achieved. Traditional nutrient management strategy was highly dependent on external chemical fertilizer input, but ignored exploring biological potential of efficient acquisition and use of soil nutrient resources by plants intrinsically. Rhizosphere is the key center of interactions among plants, soils and microorganisms; the chemical and biological processes occurring in the rhizosphere not only determine mobilization and acquisition of soil nutrients, but also control nutrient use efficiency by crops. The rhizosphere management strategy lays emphasis on maximizing the efficiency of root and rhizosphere processes in nutrient acquisition towards high-yield and high-efficiency sustainable crop production by optimizing nutrient supply in root zone, regulating root morphological and physiological traits, and manipulating rhizosphere processes and interactions.
Keywords
- حسین پور، ع. 1387. شیمی و حاصلخیزی خاک. انتشارات دانشگاه پیام نور.
- خوش گفتارمنش، ا. ح. 1389. مباحث پیشرفته در تغذیه گیاه. مرکز نشر دانشگاه صنعتی اصفهان.
3. Ae, N,. Arihara, J,. Okada, K,. Yoshihara, T,. Johansen ,C. 1990.Phosphorus uptake by pigeon pea and its role in cropping systems of the Indian subcontinent. Science 248, 477–480.
4. Bindra, A. S. 1983. Iron cholorosis in horticulture and field crops .Kalyani Publishers . NewDehli.
5. Boucher , D. H and Espinosa , J.1982 Cropping system and growth and nodulation responses of beans to nitrogen in Tabasco, Mexico. Tropical ulture. Agric. (Trinidad) 59: 279–282.
6. Hinsinger, P,. Plassard, C,. Tang, C and Jaillard, B. 2003. Origins of root- mediated pH changes in the rhizosphere and their responses to environmental constraints: A review. Pant and Soil 284: 43-59.
7. Horst,W. J and Waschkies, C.H .1987. Phosphatversorgung von Sommer-weizen (Triticum aestivum L.) in Mischkultur mit weisser Lupine (Lupinus albus L.). Z. Pflanzenerahr. Bodenk. 150:1–8.
8. Hutsch, B.W., Augustin, J., Merbach,W. 2002.Plant Rhizodeposition-an important source for carbon turnover in soils. Journal of Plant Nutrition and Soil Science- 165,397-407.
9. Jing, J.Y,. Rui, Y.K,. Zhang ,F.S,. Rengel.Z,. and Shen,J.B. 2010. Localized application of phosphorus and ammonium improves growth of maize seedlings by stimulating root proliferation and rhizosphere acidification. Field Crops Research119: 355–364.
10. Liljeroth,E,. Van Veen, J.A,.and Miller, H.J. 1990. Assimilate translocation to the rhizosphere of two wheat lines and subsequent utilization by rhizosphere microorganisms at two soil nitrogen concentrations. Soil Biolgy and Biochemistry 22:1015–1021.
11. Marschner, P. 2012. Mineral nutrition of higher plants, 3rd edn.London: Academic Press.
12. McCully, M.E,.and Boyer, J.S. 1997. The expansion of root cap mucilage during hydration: III. Changes in water potential and water content. Plant Physiology 99:169–177.
13. McNear,D.H. 2013. The rhizospher- Root, Soil and Everything in Between.Nature Education Knowledge.4(3):1-10.
14. Meharg,A.A. 1994. A critical review of labeling techniques used to quantify rhizospher carbon- flow. Plant and Soil.166:55-62.
15. Midmore, D. J. 1993. Agronomic modification of resource use and intercrop productivity. Field Crop. Researche. 34: 357–380.
16. Nye ,P.H.1981.Change of pH across the rhizosphere induced by roots .Plant and Soil.61: 7-26.
17. Raghothama, K.G.1999. Phosphate acquisition. annued review of plant physiology. Plant Molecular. Biology. 50:665-693.
18. Rovira, A.D.1969. Plant root exudates. Botanical Review. 35(1):35-57.
19. Shen. J., Li. C., Mi. G., Li. L., Yuan.L., Jiang.R and Zhang. F. 2013. Maximizing root / rhizosphere efficiency to improve crop productivity and nutrient use efficiency in intensive agriculture of china. Journal of Experimental Botany 64(5): 1181-1192.
20. Stern, W. R. 1993. Nitrogen fixation and transfer in intercrop systems. Field Crop. Research. 34: 335–356.
21. Walker,T.S., Bais, H.P., Grotewold, E., and Vivanco, J. 2003. Root exudation and rhizospher biology. American Society of Plant Biology. Vol:132.
22. Wallace, A. and Wallace, G. A. 1992. Some of problems concerning iron nutrition of plants after four decades of synthetic chelating agents. Journal of Plant Nutrition.15(10):1487- 1508.
23. Yang,Y., Wang,Q.L., Geng, M.J., Guo, Z.H.,and Zhao, Z. 2011. Rhizosphere pH difference regulated by plasma membrane H+-ATPase is related to differential Al-tolerance of two wheat cultivars. Plant Soil Environment,57(5): 201-206.
24. Zhang, F., Shen, J., Li, L and Liu, X. 2004. An overview of rhizosphere processes related with plant nutrition in major cropping system in china. Plant and Soil 260: 89-99.
25. Zhang, F., Shen, J., Jing, J., Li, L.,and Chen, X. 2010. Rhizosphere processes and management for improving nutrient use efficiency and productivity: Implicatin for China.Molecular Environmental Soil Science at the interfaces in the Earth,s Critical Zone.107:52-54.
26. Zuo, Y and Zhang, F. 2011. Soil and crop management strategies to prevent iron defficiency in crops. Plant Soil. 339: 83-95.