Role of root exudates and root turnover in the below-ground N transfer from Canavalia ensiformis (jackbean) to the associated Musa acuminata (banana)

Autor: Lucienne Desfontaines, Jorge Sierra
Přispěvatelé: Unité de Recherche AgroPédoClimatique de la zone caraïbe (APC), Institut National de la Recherche Agronomique (INRA)
Jazyk: angličtina
Rok vydání: 2009
Předmět:
0106 biological sciences
exsudat
sol
[SDV]Life Sciences [q-bio]
décomposition
Plant Science
association culturale
15N LABELLING
01 natural sciences
expérimentation sous serre
azote isotopique
Green manure
musa acuminata
marquage isotopique 15n
Musa acuminata
sol tropical
transfert d'azote racinaire
Legume
sécrétion racinaire
modélisation
2. Zero hunger
biology
turnover
food and beverages
engrais vert
dilution de l'azote
Intercropping
04 agricultural and veterinary sciences
légumineuse herbacée
Herbaceous plant
biology.organism_classification
banane
Musaceae
Horticulture
MARQUAGE 15 N
Agronomy
Canavalia ensiformis
[SDE]Environmental Sciences
canavalia ensiformis
040103 agronomy & agriculture
0401 agriculture
forestry
and fisheries

Agronomy and Crop Science
Plant nutrition
010606 plant biology & botany
Zdroj: Crop and Pasture Science 3 (60), 289-294. (2009)
Crop and Pasture Science
Crop and Pasture Science, 2009, 60 (3), pp.289-294. ⟨10.1071/CP08215⟩
ISSN: 1836-0947
Popis: International audience; Jackbean is an annual legume frequently used as green manure in tropical intercropping systems with bananas. Although the beneficial effect of nitrogen (N) release from above-ground residues on banana nutrition is well known, little information is available on the N transfer from jackbean roots before and after the above-ground harvest. The aim of this study was to assess the relative contribution of exudates and root turnover in the N transfer from jackbean to banana in a greenhouse experiment. Nitrogen transfer was studied in a 6-month trial using the 15N leaf feeding method, and estimated with a box model of 15N dilution based on the observed data of 15N content in exudates and decomposing roots. For the sowing–harvest period, the amount of N transferred from jackbean exudates represented 16% of banana N uptake and 0.7% of jackbean N uptake. Therefore, the N transfer flux via exudates was 23 times higher in terms of N input for the recipient plant than in terms of N output for the donor plant. This value, which is an index of the effectiveness of N transfer, was lower than those reported previously for other soil–plant systems in greenhouse conditions. This would be due to differences in root traits of the recipient plants. The amount of transferred N from root turnover after jackbean harvest represented 52% of banana N uptake in that period. The box model described N transfer from both legume N sources adequately (r2 = 0.92). For the whole experiment, 38% of banana N uptake was derived from jackbean (6% from exudates and 32% from root turnover), and 62% from soil N. The results indicated that N transfer from root exudates of jackbean would be a useful but minor process compared with N release from root turnover in soil. The experimental and theoretical approach proposed in this study may be useful in screening studies to assess the capability of herbaceous legumes to transfer N.
Databáze: OpenAIRE