Publication Date
1985
Location
Kyoto Japan
Description
Experiments were conducted to determine the nitrogen(N)-fixing activities of the tropical forage grasses in Taiwan, the relationship between N-fixing activity and soil fertility and the morphological and the physiological properties of the associated bacteria. Hybrid napier grass (Pennisetum americanum X P. purpureum) cv.A7005 was the most effective in N fixation among 13 species of forage grasses,with 97 nmoles C2H4 per gram dry roots per hour. A negative correlation was found between N activity and total N content in soil. However, no relationship was observed between N-fixing activity and pH value, organic matter, and available P and K in soil. An associated bacteria was isolated from Digitaria decumbens. It was identified to be Azospirillum brasilense. The bacteria was microaerophilic in the medium without N and it was Gram-negative with the size of 0.9X 2.0 µ,m. It was single polar flagellum and rod shape which could be cultured in Dobereiner's medium without N and biotin. However, it could't grow in N-free medium when glucose was used as the only carbon source. The bacteria could utilize different carbon sources, such as citrate, ethanol, latic acid, malate, and succinate.
Citation
Lee, K C., "Studies on Nitrogen Fixation of Forage Grasses in Taiwan" (1985). IGC Proceedings (1985-2023). 11.
(URL: https://uknowledge.uky.edu/igc/1985/ses6/11)
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Studies on Nitrogen Fixation of Forage Grasses in Taiwan
Kyoto Japan
Experiments were conducted to determine the nitrogen(N)-fixing activities of the tropical forage grasses in Taiwan, the relationship between N-fixing activity and soil fertility and the morphological and the physiological properties of the associated bacteria. Hybrid napier grass (Pennisetum americanum X P. purpureum) cv.A7005 was the most effective in N fixation among 13 species of forage grasses,with 97 nmoles C2H4 per gram dry roots per hour. A negative correlation was found between N activity and total N content in soil. However, no relationship was observed between N-fixing activity and pH value, organic matter, and available P and K in soil. An associated bacteria was isolated from Digitaria decumbens. It was identified to be Azospirillum brasilense. The bacteria was microaerophilic in the medium without N and it was Gram-negative with the size of 0.9X 2.0 µ,m. It was single polar flagellum and rod shape which could be cultured in Dobereiner's medium without N and biotin. However, it could't grow in N-free medium when glucose was used as the only carbon source. The bacteria could utilize different carbon sources, such as citrate, ethanol, latic acid, malate, and succinate.
