Tropical Agriculture and Development
Online ISSN : 1882-8469
Print ISSN : 1882-8450
ISSN-L : 1882-8450
Original Article
Endophytic Nitrogen-Fixing Bacteria of Water Yam (Dioscorea alata L.) in Relation with Fertilization Practices
Michel OUYABEHidehiko KIKUNONaoto TANAKAPachakkil BABILHironobu SHIWACHI
著者情報
キーワード: Diazotrophs, δ15N, %Ndfa
ジャーナル フリー

2019 年 63 巻 3 号 p. 122-130

詳細
抄録

Plant internal environment harbors several microorganisms that exhibit beneficial effects to the growth, adaptability and productivity of their host plants. Diazotrophs are bacteria responsible for biological nitrogen fixation (BNF) in plants. Yam (Dioscorea spp.) is an important tuber crop for food security in West Africa, but also is the most neglected crop in term of research. This experiment evaluated endophytic nitrogen-fixing bacteria associated with water yam (D. alata) grown under different fertilizer regimes and the biological nitrogen fixation in non-fertilized plants through leaf δ15N. Pot experiment was conducted for 180 days and plants were treated with urea and cow manure. Nitrogen content in plant was increased under urea treatment. Nitrogen uptake was higher in urea as compared to non-treated plants. Leaf δ15N of control plants decreased over time from 60 days after planting (DAP) in all accessions and BNF ranged from 13% to 40%. At 180 DAP, 47 bacterial strains were identified at the species level grouped into three phyla. Proteobacteria represented 77% of total isolates and most isolates were from the roots. The predominant genera were Rhizobium, Mesorhizobium and Devosia. Using the culture-dependent method in this study, it was clear that fertilization practice affected the type and number of endophytic nitrogen-fixing bacteria associated with water yam. Twenty (20) to 32 % of isolated bacterial strains were specific to each treatment and only 8% were common to all treatments.

著者関連情報
© 2019 Japanese Society for Tropical Agriculture
前の記事 次の記事
feedback
Top