外源氮对离体麦穗干物质及氮素积累的影响

采用离体穗培养的方法,选取花后7d的周麦18为材料,研究了外源氮(0、0.5、1.0、2.0 g/LNH4NO3)对离体麦穗干物质及氮素积累的影响。结果表明,随培养天数的增加,离体穗干物质积累总量呈增加趋势,外源氮促进了离体穗干物质的积累,提高了干物质在籽粒中的分配比例。在外源氮供给下,离体穗营养器官干物质向籽粒的转移率和贡献率均降低,籽粒光合产物积累量增加。外源氮增加了籽粒中氮素的含量和积累量,提高了离体穗中氮素在籽粒中的分配比例。在本试验中,2.0 g/L NH4NO3处理效果最佳,促进了离体穗尤其是籽粒的生长,提高了籽粒的氮素含量和积累量,对籽粒建成具有促进作用。

Effects of N on Dry Matter and N Accumulation of Detached Wheat Spikes In Vitro Culture

Taking Zhoumai 18 as experiment material,the effects of N on dry matter and N accumulation of detached wheat spikes in vitro culture were studied under different levels of N application(0,0.5,1 and 2g/L NH4NO3,respectively).The spikes were collected 7 days after anthesis.The results showed that the dry matter accumulation of detached spikes increased with the increase of culture time.Exogenous N promoted the dry matter accumulation and improved the distribution rate in grains in detached spikes.The supply of exogenous N decreased the translocation efficiency of dry matters from vegetative organs and their contribution rate to grain,but the photosynthetic product in grains increased.Exogenous N also improved the N accumulation in detached spikes,increased the N content and accumulation in grains,and promoted the N distribution rate in grains.In the study,the best treatment was 2.0g/L NH4NO3.