Samira R. Mansour
Botany Department, Faculty of Science, Suez Canal University, lsmailia, Egypt
ABSTRACT
Some factors affecting the establishment of Casuarina-Frankia symbioses were studied by following the survival of some Frankia strains exposed to different environmental soil conditions. This was accomplished by examining the effect of soil desiccation at 30oC temperature or to intermittent exposure of desiccated soil to 50oC (3h on three consecutive days) and different soil pHs on nodulation. Six Frankia strains were isolated from different Casuarina plantations and were used in this study. Frankia survival, was measured as the persistence of nodulation capacity using the plant infection technique. The survival of introduced Frankia fell markely in soils undergoing drying. The extent of decline varied with strain and soil. The decrease in numbers for all strains after desiccation was greater in reclaimed soil than other soils tested. The survival of all Frankia strains in response to desiccated soil was higher with intermittent exposure to 50oC than when desiccated at 30oC. The survival of introduced Frankia varied with adjusted soil pHs. Survival was often higher at pH 8, but usually was adversely affected by higher pH (pH 8.5). Recovery of introduced Frankia into autoclaved soils, exposed to different treatments, was significantly higher than non-autoclaved soil.
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How to cite this article
Samira R. Mansour, 2003. Survival of Frankia
Strains under Different Soil Conditions. Journal of Biological Sciences, 3: 618-626.
DOI: 10.3923/jbs.2003.618.626
URL: https://scialert.net/abstract/?doi=jbs.2003.618.626
DOI: 10.3923/jbs.2003.618.626
URL: https://scialert.net/abstract/?doi=jbs.2003.618.626
REFERENCES
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Direct Link - Nelson, D.W. and L.E. Sommers, 1996. Total Carbon, organic carbon and organic Matter. In: Methods of Soil Analysis, Part 3: Chemical Methods, Sparks, D.L., American Society of Agronomy/Soil Science Society of America, Madison, WI., USA., ISBN-13: 978-0891188254, pp: 961-1010.
Direct Link