Below-ground carbon distribution in barley (Hordeum vulgareL.) with and without nitrogen fertilization

✍ Scribed by Gerd Johansson

• Publisher: Springer
• Year: 1992
• Tongue: English
• Weight: 582 KB
• Volume: 144
• Category: Article
• ISSN: 0032-079X
• DOI: 10.1007/bf00018849

✦ Synopsis

The distribution of net assimilated C in barley (Hordeum vulgare L.) grown at two N-levels was determined in a growth chamber. The N-fertilization involved 0 and 3.61 ~mol N g-I dry soil. After growth for seven weeks in an atmosphere with continuously ~4C-labelled CO 2, 14C was determined in shoots, roots, rhizosphere respiration and soil. At the low N-level, 32% of the net assimilated ~4C was translocated below ground, whereas at the high N-level 27% was translocated below ground. The release of C from roots (root respiration, microbial respiration originating from decomposition of 14C-labelled root material and ~4C remaining in soil) was greater with no N-supply (19% of net assimilated ~4C) than in the treatment with N-supply (15%). Thus, the effect of N-supply on both translocation of assimilated ~4C below ground and the release of ~4C from growing roots was relatively small.