芸苔素内酯浸泡处理对苦草生长的影响

Effect of Brassinolide Soaking Treatment on Growth of Vallisneria natans

在水生态修复工程中,移栽后的苦草(Vallisneria natans(Lour.)Hara)往往存在生长状况不佳、适应期长等问题。现有报道表明,芸苔素内酯在促进植物生长代谢方面具有显著效果。该研究尝试采用浸泡预处理方式,研究不同浓度(0、0.25、0.5、1、2和4 mg/L)和浸泡时间(10、20和40 min)芸苔素内酯对苦草生长的影响。结果表明:经芸苔素内酯预处理后的苦草,其生物量、株高、叶片数、分蘖数及叶绿素等指标均有不同程度提升,且表现为浸泡浓度的影响大于浸泡时间。3种浸泡时间下,苦草的生物量均在0.5 mg/L出现最大值,其中浸泡10 min的促进效果最优;从株高指标来看,浸泡时间为10 min时,浓度为0.25~2 mg/L的芸苔素内酯对苦草株高均有显著促进效果(P<0.05);从叶绿素指标来看,芸苔素内酯浓度为0.5~1 mg/L,浸泡10 min对叶绿素a、叶绿素b含量促进效果最好。基于实验数据,考虑到经济和时间成本,建议苦草移栽前用浓度为0.5 mg/L的芸苔素内酯浸泡10 min,可有效改善苦草定植问题。研究可为水环境中沉水植物的快速恢复提供理论参考。

In aquatic ecological restoration projects,V.natans(Vallisneria natans(Lour.)Hara),a species of submergent plant,after being transplanted often experiences a poor growing condition and a lengthy adaption period,however,brassinolides possess considerable effectiveness of plant development and metabolism according to available research reports.In an attempt to employ a phytohormone soaking pre-treatment method to study the effect of brassinolides’effect on V.natans development,a laboratory experiment was conducted probing into the influencing factors:brassinolides dosage(0,0.25,0.5,1,2 and 4 mg/L)and soaking time(10,20,and 40 minutes).The results showed that the pre-treatment with brassinolide facilitated the improvement to some extent of biomass,plant height,number of leaves,number of tillers,and chlorophyll of V.natans,and that the effect of soaking solution concentration was more pronounced than immersion time;it appeared that under the condition of above three soaking intervals the biomass of V.natans increased to the maximum at the solution concentration of 0.5 mg/L;however,10 min soaking time gave rise to biggst boosting effect,and from the perspective of plant height indicator,as the soaking time was 10 min brassinolide of 0.25~2 mg/L concentration had a notable positive effect on the plant height of V.natans(P<0.05).In terms of chlorophyll indicators,it was the best condition that the content of chlorophyll a and chlorophyll b of V.natans was boosted when brassinolide concentration ranged 0.5~1 mg/L and soaking time was 10 min.In accordance with the experimental data obtained and considering economic cost and time cost,it is recommended that prior to the transplantation V.natans be soaked with brassinolide at a concentration of 0.5 mg/L for 10 min,in this way the problem of V.natans colonizationcan could be successfully solved.Finally,it is expected that the experimental results could provide theoretical references for the quick recovery of submerged macrophytes in aquatic environment.