Decomposition of lupine seeds and seedlings as N fertilizer in organic vegetable production

authored by

Kai Uwe Katroschan, Gonçalo Teixeira, Katrin Kahlen, Hartmut Stützel

Abstract

Background and aims: Nitrogen mineralization of lupine seeds and seedlings to be used as flexible leguminous N source in organic vegetable production was investigated. It was hypothesized that changes in seed chemical composition during germination are associated with increased fertilizer efficiency of seed N. Methods: Net N mineralization of seed meal and seedlings varying in age was determined in pot and field experiments. The temporal mineralization pattern was quantified by fitting first-order kinetics. Results: In the pot experiment, seedling C:N ratio declined within 2 weeks from initially 8. 8 to a minimum of 6. 2 prior to a re-increase. Maximum net N mineralization increased strongly with decreasing C:N ratio being up to 44% higher for seedlings compared to seed meal. Time course of net N mineralization in the field showed initial peaks partly exceeding the amount of applied lupine seed N. Ignoring mineralization peaks, the relationship between maximum net N mineralization and C:N ratio was in close agreement with pot experimental data. The critical C:N ratio of the pooled data was 13. Conclusions: Nitrogen mineralization of field-sown lupine seeds can be manipulated by varying seedling growing time until incorporation. High fertilizer efficiency provided by high net N mineralization is associated with early seedling incorporation and high germination rates.

Organisation(s)

Institute of Horticultural Production Systems

External Organisation(s)

Landesforschungsanstalt für Landwirtschaft und Fischerei Mecklenburg-Vorpommern (LFA)
Hochschule Geisenheim University

Type

Article

Journal

Plant and soil

Volume

357

Pages

59-71

No. of pages

13

ISSN

0032-079X

Publication date

23.02.2012

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Soil Science, Plant Science

Sustainable Development Goals

SDG 2 - Zero Hunger

Electronic version(s)

https://doi.org/10.1007/s11104-012-1144-4 (Access: Closed)