不同小麦品种苗期对混合形态氮素营养的反应

采用水培方法研究了不同基因型小麦对不同NH 4/NO-3 混合比例营养的反应。结果表明 ,增铵营养对 40个基因型小麦的早期生长均有促进作用 ,但各个基因型的表现不尽一致。与单一NO-3 营养相比 ,增铵营养显著提高了茎干重、总干重、单株分蘖数、叶片叶绿素含量、植株氮含量和氮积累量 ,但对根干重没有影响。营养液中 2 5 %～ 5 0 %的NH 4比例对植株生长更为有利。与单一NO-3 营养相比 ,单一NH 4营养下植株的叶绿素含量和氮含量较高 ,但茎干重、总干重、单株分蘖数和氮积累量较低。分析表明 ,植株在增铵营养中干物质积累的增加与单株分蘖数和氮积累量相关。

Responses of different wheat varieties to mixed NH+4/NO-3 nutrition at early stage

Two experiments were conducted under controlled hydroponics to investigate the growth responses of different varieties to mixed NH 4/NO - 3 percentages in wheat.The results indicated that enhanced ammonium nutrition(EAN)increased early growth of all 40 genotypes to a certain extent.Compared with NO - 3 alone,EAN significantly increased shoot dry weight(DW),total DW,tillers per plant,leaf chlorophyll content,nitrogen content and nitrogen accumulation except for root DW.Especially,25%?50% NH 4 in solution was most favorable to growth.Plants grown with NH 4 alone exhibited higher chlorophyll content and nitrogen content,but less shoot DW,total DW,tillers per plant and nitrogen accumulation as compared with NO - 3 alone.It was shown that enhancement of total plant DW by EAN was associated with increased tillering and nitrogen accumulation.