氟啶酮与赤霉素组合对沙米种子萌发与出苗的影响

Effects of combined fluridone and gibberellin on the germination and emergence of Agriophyllum squarrosum seeds

种子萌发出苗是流动沙丘先锋植物沙米(Agriophyllum squarrosum)成功实现自然更新的关键环节,也是制约其人工栽培的重要因素。选取当年采收的沙米种子为试验材料,研究了氟啶酮(fluridone,FL)不同浓度、浸种时长以及与赤霉素(gibberellin,GA3)组合对沙米种子萌发和出苗的影响,筛选有效促进沙米萌发和出苗的FL+GA3组合。研究结果表明,FL溶液浸种能有效打破沙米种子的休眠,其浓度大小和浸种时长决定沙米种子萌发速度的快慢和发芽率的高低,0.1%~10%浓度范围内沙米种子发芽率随FL浓度增大而逐渐提高;3~24 h浸种时间内沙米种子发芽率随时长逐渐增大,浸种时长在24 h发芽率达到最高。单一FL适宜浓度为5.0μmol·L−1,浸种时长为24 h。在FL溶液加入GA3后,协同作用不仅提高了低浓度FL溶液的出苗率,也解决了单一FL溶液处理幼苗死亡率高的问题。优选出5.0μmol·L^(−1)FL+2.0 g·L^(−1)GA3组合,该组合处理后,沙米种子的发芽率提高,发芽速度加快,且幼苗的保存率也达到最高,可为沙米大田人工栽培提供理论依据和技术支撑。

Seed germination is key to successful natural regeneration of the pioneer plant Agriophyllum squarrosum in moving dunes.Additionally,it is an important factor restricting its artificial cultivation.Seeds collected in the current year were used to study the effects of different fluridone(FL)concentrations and soaking times,alone and in combination with gibberellin(GA3),on seed germination and emergence and to screen for the FL+GA3 combination that most effectively promoted seed germination and emergence.FL immersion effectively broke A.squarrosum seed dormancy,and the effects of FL concentration and duration of immersion on A.squarrosum seed germination rate were determined.The germination rate of A.squarrosum seeds increased gradually with increasing FL concentrations in the range of 0.1%to 10%.The germination rate increased gradually with increasing immersion times within a 3~24 h range,reaching its maximum with 24 h immersion.The optimal FL concentration was 5.0μmol·L^(−1),and the optimal soaking time was 24 h.Adding GA3 to an FL solution synergistically enhanced emergence rates obtained with low FL concentrations and abrogated the high mortality rate of seedlings treated with FL alone.5.0μmol·L^(−1)FL+2.0 g·L^(−1)GA3 was optimal.This combination treatment increased the A.squarrosum seed germination rate and achieved the highest seedling preservation rate,which could provide a theoretical basis and technical support for the artificial cultivation of A.squarrosum in the field.