不同施肥下冬小麦生长过程中土壤矿质氮变化及其与冬小麦叶片SPAD值的关系

Changes of Soil Mineral Nitrogen and Its Relationship with Soil and Plant Analyzer Development (SPAD) Values of Winter Wheat Leaves During Winter Wheat Growth Under Different Fertilization

通过调查分析,研究了土长期施肥条件下土壤中矿质氮含量变化及其与地上冬小麦叶片SPAD值。结果表明:(1)整个冬小麦生长期不同土层硝态氮和铵态氮的变化趋势不一致,硝态氮含量是先下降后上升的变化,而铵态氮含量呈一直上升的变化趋势。在没有施过氮肥的处理中,0—20cm,20—40cm土层中土壤硝态氮、铵态氮含量显著低于施用氮肥的处理;(2)冬小麦生长时期,各个处理叶片SPAD值各异,但都是先升高后下降的变化,无氮肥施用的叶片SPAD值低于施氮肥的处理;(3)冬小麦各个生长时期叶片SPAD值与土壤不同层次(0—20cm,20—40cm)硝态氮含量呈正相关关系,而与铵态氮含量相关性不显著,这表明小麦是对硝态氮较为敏感的作物。本试验结果可以为进一步合理调控氮肥施用、明确施氮对小麦产量和品质的影响提供一定的基础依据。

Through the investigation and analysis,the soil and plant analyzer development(SPAD)values of winter wheat leaves and mineral nitrogen contents of Lou soil under the long-term fertilization were characterized.The results showed that:(1)the changes of nitrate nitrogen and ammonium nitrogen contents in different soil layers were not consistent during the winter wheat grwoth period.The contents of nitrate nitrogen were decreased first and then increased,while the content of ammonium nitrogen has been rising,the contents of nitrate nitrogen and ammonium nitrogen of treatment with no nitrogen fertilizer were significantly lower than those of treatments with nitrogen fertilizer in the different soil layers(0—20cm,20—40cm);(2)during the growth period of winter wheat,the SPAD values of all treatments were different,but all of which first increased and then decreased.The SPAD values of leaves under the treatment with no nitrogen fertilizer were lower than those of the treatments with nitrogen fertilizer application;(3)during winter wheat growth period,SPAD values of leaves and nitrate nitrogen contents were significantly positively correlated in different soil layers(0—20cm,20—40cm),while their correlation with the content of ammonium nitrogen was not significant,indicating that wheat is sensitive to nitrate nitrogen to some extent.The results could provide the reference for manipulation of the nitrogen fertilizer application and understanding the effect of nitrogen fertilization on the yield and quality of winter wheat.