低氮胁迫下黄瓜根系相关指标的变化

Changes of Pertinent Indices in Cucumber Root System under Low-nitrogen Stress

以耐低氮性强的黄瓜品种D0328和耐低氮性弱的黄瓜品种东农806为试材,进行两种水平的施氮处理,对植株发育过程中根系的各项指标进行对比分析。结果表明;低氮胁迫条件下,盛果期之前两个黄瓜品种根体积、根干质量和根系活力升高,盛果期之后降低;根系伤流量在结果初期之前上升,而后下降;冠根比在整个生育期中一直呈上升的趋势。两个黄瓜品种结果初期根系伤流量差距最大,D0328明显低于东农806,因此低氮胁迫下结果初期根系伤流量可作为黄瓜耐低氮品种的筛选指标。

Two cucumber cultivars'D0328'and'Dongnong 806'with widely different low-nitrogen tolerance indices were chosen as test materials,in order to find the changing mechanism through studying the changes in several indices of both cucumber roots during the whole period of duration.The result showed that in the case of low-nitrogen stress,the root volume,root dry weight and root vigor of both cultivars all increased before the full bearing stage and then decreased.However,the bleeding flow rate of both roots increased before the bearing primary stage and then decreased.And the root vigor increased straightly.The difference of root bleeding flow rate was the most significant during the initial bearing stage,so it could be used as the most suitable screening index for cucumber under low-nitrogen stress.