Abstract: This research took the seeds of Alcea rosea Linn. as the experimental material. Drought stress was simulated using PEG-6000， and salt stress was simulated with NaCl. By adopting the method of a randomized block design experiment， an exploration was conducted on the germination responses of A. rosea seeds to drought， salt， and their interactive stresses， with the aim of revealing their tolerance thresholds. The results indicated that under single drought stress， as the degree of drought intensified， all germination indicators declined. Under severe drought condition （25% PEG-6000， -0.73 MPa）， the seeds completely lost their germination ability. Under single salt stress， the germination indicators decreased as the NaCl concentration increased. When the NaCl concentration exceeded 0.20 mol·L^-1， germination ceased. Under interactive stresses， the combination of extremely mild drought （5% PEG） and extremely low-salt levels （<0.05 mol·L^-1 NaCl） could promote germination. Under moderately severe to severe drought conditions （>20%PEG， -0.49 MPa）， low-salt levels （<0.10 mol·L^-1） could sustain germination. Even under high-salt conditions （>0.20 mol·L^-1）， light/mild to moderate drought （<15% PEG， -0.30 MPa） could still allow some seeds to germinate. However， when the NaCl concentration was greater than 0.20 mol·L^-1 and the PEG concentration was greater than 25%， the seeds could not germinate at all. The critical germination value （50% germination rate） occurred under the interactive conditions of 10%-12% PEG （-0.20--0.15 MPa） and 0.05-0.08 mol·L^-1 NaCl. The tolerance limit （25% germination rate） was found under the interactive conditions of 17%-20% PEG （-0.49--0.37 MPa） and 0.12-0.14 mol·L^-1 NaCl. This study systematically reveals the response patterns and physiological tolerance thresholds of A. rosea seeds to combined stresses， providing crucial insights for understanding its adaptation mechanisms under complex environmental constraints.

Key words: Alcea rosea, Seed germination, Drought stress, Salt stress, Combined stress

摘要： 本研究以蜀葵（Alcea rosea Linn.）种子为材料，通过聚乙二醇PEG-6000模拟干旱胁迫和NaCl模拟盐胁迫，采用随机区组试验的方法，探究了蜀葵种子对干旱和盐胁迫及其交互胁迫的萌发响应，旨在揭示其耐受阈值。结果表明：单一干旱胁迫下，随干旱程度加剧各萌发指标均下降，重度干旱（25% PEG-6000，-0.73 MPa）时种子完全丧失萌发能力。单一盐胁迫下，萌发指标随NaCl浓度升高而降低，高盐NaCl>0.20 mol·L^-1时萌发停止。交互胁迫下，极轻度干旱（5% PEG）与极低盐（<0.05 mol·L^-1 NaCl）组合可促进萌发；中偏重度干旱（>20% PEG，-0.49 MPa）下低盐（<0.10 mol·L^-1）可维持萌发，而高盐（>0.20 mol·L^-1）下轻中度干旱（<15% PEG，-0.30 MPa）仍可使部分种子萌发；NaCl>0.20 mol·L^-1且PEG>25%时，种子完全不能萌发。萌发临界值（50%发芽率）在10%~12% PEG（-0.20~-0.15 MPa）与0.05~0.08 mol·L^-1 NaCl交互下；耐受极限（25%发芽率）为17%~20% PEG（-0.49~-0.37 MPa）与0.12~0.14 mol·L^-1NaCl交互下。研究结果系统揭示了蜀葵种子对复合胁迫的响应规律及其生理耐受阈值。

关键词: 蜀葵, 种子萌发, 干旱胁迫, 盐胁迫, 复合胁迫