Eliminating Aluminum Toxicity in an Acid Sulfate Soil for Rice Cultivation Using Plant Growth Promoting Bacteria

Molecules

Qurban Ali Panhwar²  Umme Aminun Naher¹  Othman Radziah²  Jusop Shamshuddin²  Ismail Mohd Razi¹ 

[1] Institute of Tropical Agriculture, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia;Department of Land Management, Faculty of Agriculture, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia

关键词: Al speciation;    chelation;    indoleacetic acid;    phytohormone;    ameliorative effect;   

DOI  :  10.3390/molecules20033628

来源: mdpi

【 摘 要 】

Aluminum toxicity is widely considered as the most important limiting factor for plants growing in acid sulfate soils. A study was conducted in laboratory and in field to ameliorate Al toxicity using plant growth promoting bacteria (PGPB), ground magnesium limestone (GML) and ground basalt. Five-day-old rice seedlings were inoculated by Bacillus sp., Stenotrophomonas maltophila, Burkholderia thailandensis and Burkholderia seminalis and grown for 21 days in Hoagland solution (pH 4.0) at various Al concentrations (0, 50 and 100 μM). Toxicity symptoms in root and leaf were studied using scanning electron microscope. In the field, biofertilizer (PGPB), GML and basalt were applied (4 t·ha⁻¹ each). Results showed that Al severely affected the growth of rice. At high concentrations, the root surface was ruptured, leading to cell collapse; however, no damages were observed in the PGPB inoculated seedlings. After 21 days of inoculation, solution pH increased to >6.0, while the control treatment remained same. Field study showed that the highest rice growth and yield were obtained in the bio-fertilizer and GML treatments. This study showed that Al toxicity was reduced by PGPB via production of organic acids that were able to chelate the Al and the production of polysaccharides that increased solution pH. The release of phytohormones further enhanced rice growth that resulted in yield increase.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.