Effect of nitrogen fertilization on growth and nitrogen dynamics of C hamaecrista rotundifolia cv. M inyin on red soil in southern C hina

• Published in: Grassland science 2014-06, Vol.60 (2), p.112-117
• Main Authors: Weng, Boqi, Li, Yuesen, Wang, Yixiang, Li, Yanchun
• Format: Article
• Language: English
• ISSN: 1744-6961; 1744-697X
• DOI: 10.1111/grs.12050

A leguminous forage plant, round‐leaf cassia ( C hamaecrista rotundifolia (Pers.) Greene cv. Minyin), is ecologically important in the hilly, red soil regions of southern China. This study investigated the effects of nitrogen (N) fertilization at the rates of 0, 30, 60, 90 and 120 kg ha −1 on the growth and N dynamics (including biological N fixation, N uptake, N accumulation and fate of N fertilizer) of the pot‐grown Minyin in an attempt to optimize the fertilization. The increased fertilization increased the percentage of N derived from the fertilizer ( P   <   0.01), but decreased that from the soil ( P   <   0.05) and also reduced the number of root nodules ( P   <   0.01). At 60 kg ha −1 application rate, the N fixation efficiency ( NFE ) of the plant peaked at 29.5% and the N use efficiency ( NUE ) of the fertilizer at 27.9%. When the highest rate of fertilization (120 kg ha −1 ) was applied, NFE was significantly decreased (11.1%) and NUE reduced to 23.0%. It showed that Minyin was highly efficient (varying from approximately 11–30% NFE ) in fixing N from the atmosphere, and could suitably be promoted for the N‐deficient hilly, red soil regions in southern C hina.