Mwajita Mwashasha Rashid, Murage Hunja, Tani Akio, Kahangi Esther M
Kenya Agricultural Research Institute, PO Box 57811-00200, Nairobi, Kenya.
Jomo Kenyatta University of Agriculture and Technology, PO Box 62000-0020, Nairobi, Kenya.
Springerplus. 2013 Nov 13;2:606. doi: 10.1186/2193-1801-2-606. eCollection 2013.
Rice (Oryza sativa L.) is the most important staple food crop in many developing countries, and is ranked third in Kenya after maize and wheat. Continuous cropping without replenishing soil nutrients is a major problem in Kenya resulting to declining soil fertility. The use of chemical fertilizers to avert the problem of low soil fertility is currently limited due to rising costs and environmental concerns. Many soil micro-organisms are able to solubilize the unavailable phosphorus, increase uptake of nitrogen and also synthesize growth promoting hormones including auxin. The aim of this study was to isolate and characterize phyllosphere, rhizoplane and rhizosphere micro-organisms from Kenyan rice with growth promoting habits. In this study whole plant rice samples were collected from different rice growing regions of Kenya. 76.2%, over 80% and 38.5% of the bacterial isolates were positive for phosphate solubilization, nitrogenase activity and IAA production whereas 17.5% and 5% of the fungal isolates were positive for phosphate solubilization and IAA production respectively. Hence these micro-organisms have potential for utilization as bio-fertilizers in rice production.
水稻（Oryza sativa L.）是许多发展中国家最重要的主食作物，在肯尼亚仅次于玉米和小麦，排名第三。在肯尼亚，不补充土壤养分的连作是一个主要问题，导致土壤肥力下降。由于成本上升和环境问题，目前使用化肥来避免土壤肥力低下问题受到限制。许多土壤微生物能够溶解难溶性磷、增加氮的吸收，还能合成包括生长素在内的促进生长的激素。本研究的目的是从具有促生长习性的肯尼亚水稻中分离和鉴定叶际、根面和根际微生物。在本研究中，从肯尼亚不同水稻种植区采集了整株水稻样本。76.2%、超过80%和38.5%的细菌分离株在解磷、固氮酶活性和生长素产生方面呈阳性，而17.5%和5%的真菌分离株分别在解磷和生长素产生方面呈阳性。因此，这些微生物有潜力作为生物肥料用于水稻生产。
