摘要
在小麦/蚕豆间作体系中通过根系分隔和标记15N的盆栽试验研究表明,小麦相对于蚕豆对土壤氮和肥料氮的依赖更强,蚕豆则更多依赖于空气中的氮。在根系完全分隔、尼龙网分隔和根系不分隔处理中小麦对15N的回收率分别为58%、73%和52%,而蚕豆则分别为30%、20%和3%。小麦对肥料氮的竞争促进了蚕豆的固氮作用,在根系完全分隔、尼龙网分隔和根系不分隔时,蚕豆来源于固氮的百分数(%Ndfa)分别为58%、80%和91%。因此,小麦/蚕豆中存在对氮的互补利用,该体系中氮营养竞争和促进作用同时存在。在小麦/蚕豆间作体系中应用土壤标记同位素稀释法表明蚕豆固氮向间作小麦发生了转移,转移的量相当于蚕豆吸氮总量的5%。
A pot experiment was carried out to investigate the interspecific nitrogen facilitation between the intercropped wheat and fababean. The results from the isotope dilution method showed that wheat competed more fertilizer N than fababean, and fababean depended more on biological nitrogen fixation. 15N recovery rate of wheat with solid barrier, mesh barrier and no barrier was 58%, 73% and 52%, respectively. Nevertheless, 15N recovery rate of fababean was 30%, 20% and 3%, respectively. The results in the mesh barrier also showed that due to competition from wheat for the soil available N, the percentage of fixed N in fababean was enhanced. The percentage of N absorbed by fababean from pots with solid barrier, mesh barrier and no barrier was 58%, 80% and 91%, respectively. Therefore, the complementary N use did exist in wheat-fababean intercropping, and both the interspecific nitrogen competition and facilitation occurred in wheat-fababean intercropping. At last but not the least, the isotope dilution method showed nitrogen transfer occurred from fababean to the associate wheat, and 5% of total N of fababean was transferred to wheat.
出处
《中国农业科学》
CAS
CSCD
北大核心
2005年第5期965-973,共9页
Scientia Agricultura Sinica
基金
国家自然科学基金项目(30070450)
云南省自然科学基金项目(2004C0059M)资助
