NaCl胁迫对甜叶菊移栽苗生理生态特性的影响

通过盆栽法, 研究了不同浓度NaCl胁迫对甜叶菊移栽苗生理生态特性的影响. 结果表明: NaCl对甜叶菊移栽苗生长的胁迫表现为低促高抑的效应, 即0~44 mmol·L^-1浓度下, NaCl处理对甜叶菊移栽苗光合作用和生长具有促进作用; 44~140 mmol·L^-1浓度下, 甜叶菊光合参数、干叶产量、长势等逐渐下降; 大于140 mmol·L^-1浓度下, 甜叶菊将不能存活. 低浓度NaCl胁迫下, 甜叶菊叶生长量增加, 而茎和根的生长量与其他NaCl胁迫一样, 表现为增长量降低. 甜叶菊通过增加叶生物量适应低盐胁迫, 是甜叶菊叶子的增产新机制, 为生物量的分配研究提供了新的佐证. 此外, 所确定的Na⁺影响甜叶菊生长的低促高抑的浓度范围, 为今后甜叶菊规模化和精细化栽培种植提供了理论基础.

Effect of NaCl stress on ecophysiological characteristics of transplanting seedlings of Stevia rebaudiana Bertoni

In this paper, the effect of NaCl solution stress with different concentrations on the ecophysiological characteristics of transplanted seedlings of Stevia rebaudiana Bertoni with pot method was researched. The result showed that the NaCl solution with low concentration may promote the transplanted seedlings of stevia growing and that the NaCl solution with high concentration may suppress reversely. When the concentration is 0-44 mmol·L^-1, the NaCl solution would promote the photosynthesis and growth of transplanted seedlings of stevia; when the concentration is 44-140 mmol·L^-1, the photosynthetic parameters, dry leaf yield and growth would decrease by degrees; when concentration is greater than 140 mmol·L^-1 the stevia cannot survive. Under the stress of NaCl solution with low concentration, the leaf yield of stevia increases. However, the growing of stems and roots would be suppressed. It was a new mechanism for increasing stevia leaf yield that stevia adapt to low salt stress by increasing leaf biomass. It is revealed that new evidence for the study of allocation of biomass. Moreover, the identified Na⁺ solution range, lower than which the growth of stevia would be promoted and higher than which the growth of stevia would be inhibited, will provide theoretical basis for planting stevia in large-scale and finely.