不同氮肥施用量对草莓生长和氮转运酶的影响

Effects of Nitrogen Levels on Strawberry Growth and Nitrogen Transport Enzymes

氮肥利用率低是制约果树产业可持续发展的重要因素之一。本实验旨在探索能够提高氮肥利用效率适宜的氮用量,探究氮对草莓‘章姬’(Fragaria ananassa Duch.cv.‘Akihime’)幼苗生长及氮转运相关酶吸收、转化和分配利用特性的影响,为氮肥的科学使用奠定基础,指导科学施肥。结果表明,不同施氮水平下,每盆210 mg·kg^(-1)处理对草莓各个时期的生长量,净光合速率及叶片叶绿素含量均显著高于其他处理,增加氮肥施用量可以提高草莓根系的细胞体积和数量。各处理叶片和根系的氮含量在草莓整个生长发育期内均呈逐步上升的趋势,叶片高于根系。当施氮水平为210 mg·kg^(-1),对草莓‘章姬’植株根系和叶片谷氨酸脱氢酶、谷氨酸合成酶和谷氨酰胺合成酶活性的影响最显著。

Low nitrogen use efficiency is one of the important factors restricting the sustainable development of fruit industry.The purpose of this experiment was to explore the appropriate nitrogen application rate that could improve the nitrogen use efficiency,and explore the effects of nitrogen on the growth of Fragaria ananassa Duch.cv.‘Akihime’seedlings and the absorption,transformation and distribution and utilization characteristics of enzymes related to nitrogen transport,so as to lay the foundation for the scientific use of nitrogen and guide scientific fertilization.The results showed that under different nitrogen levels,the growth,net photosynthetic rate and chlorophyll content of strawberry in each stage of 210 mg·kg^(-1) treatment were significantly higher than those of other treatments.Increasing the amount of nitrogen fertilizer can improve the cell volume and number of strawberry roots.The nitrogen content in leaves and roots of each treatment showed a gradual upward trend during the whole growth period of strawberry,and the nitrogen content in leaves was higher than that in roots.When the nitrogen application level was 210 mg·kg^(-1),the activities of glutamate dehydrogenase,glutamate synthase and glutamine synthetase in roots and leaves of strawberry were most significantly affected.