论文部分内容阅读
采用盆栽试验,研究了Cd胁迫下施N对台湾桤木植株的干物质及N、P、K、Cd积累和分配的影响。结果表明:不施N条件下,Cd胁迫显著降低了台湾桤木根、茎和叶干物质积累量以及各器官N、P、K的积累量,在一定程度上降低了根和叶的N、K含量,但对根和叶的P含量均无显著影响;台湾桤木通过增加N、P、K和干物质在根中的分配比例,降低N、P、K在叶中的分配比例,以及提高N利用率(NUEN)和K利用率(NUEK)来更好地适应Cd胁迫环境;台湾桤木Cd的富集部位主要为根部,转移系数在0.06~0.22,而Cd的添加均降低了台湾桤木Cd转移系数和富集系数;30 mg·kg-1Cd胁迫下,施N在一定程度上提高了台湾桤木根、茎和叶干物质以及N、K含量和积累量,缓解了Cd胁迫所引起的对N、K吸收的限制,但对P含量和积累量无显著影响;施N提高了干物质在台湾桤木根中的分配比例和根冠比,而低N(0.4 g·kg-1)促进作用更明显;施N提高了Cd在台湾桤木茎、叶中的积累量和分配比例,而降低了其在根中的积累量和分配比例,提高了Cd转移系数(TF)和茎叶生物富集系数(BCF),显著降低了根BCF。说明施N有利于提高台湾桤木对Cd胁迫环境的适应能力。
A pot experiment was conducted to study the effects of N stress on the accumulation and distribution of N, P, K, Cd in alder plants under Cd stress. The results showed that Cd stress significantly reduced the accumulation of dry matter and the accumulation of N, P and K in roots, stems and leaves of Alnus cremastogyne at the condition of no N application, which reduced the N and K of roots and leaves to a certain extent , But had no significant effect on the content of P in roots and leaves. Alnus mandshurica decreased the distribution proportion of N, P and K in leaves by increasing the proportion of N, P, K and dry matter in roots, and increased N utilization ratio (NUEN) and KUE utilization rate (NUEK) to better adapt to the Cd stress environment; Taiwan alder Cd concentration of the main parts of the root, the transfer coefficient of 0.06 ~ 0.22, while the addition of Cd decreased Taiwan 桤Under Cd stress of 30 mg · kg-1Cd, application of N increased dry matter and N, K content and accumulation of roots, stems and leaves of Alnus cremastogyne in Taiwan to some extent, and alleviated the effects of Cd stress N, K absorption, but had no significant effect on the P content and accumulation; N application increased the distribution ratio and root-shoot ratio of dry matter in Alnus cremastogyne, but low N (0.4 g · kg-1) The effect of promoting was more obvious. The application of N increased the accumulation and distribution of Cd in stems and leaves of Alnus cremastogyne, but decreased the accumulation and distribution of Cd in roots Ratio increased Cd transfer coefficient (TF) and stem-leaf bioaccumulation factor (BCF), significantly reduced root BCF. This indicated that N application could improve the adaptability of Alnus cremastogyne to Cd stress environment.