葎草雌雄植株开花物候和花器官对干旱的响应差异  

Sex-specific Responses of Flowering Phenology and Floral Morphology of Humulus scandens to Drought

作　　者：杨帅[1] 王碧霞[1,2] 胥晓[1,2] 郇慧慧 秦芳[1] 陈梦华[1] 

机构地区：[1]西华师范大学生命科学学院,四川南充637002 [2]西南野生动植物资源保护教育部重点实验室,四川南充637002

出　　处：《植物分类与资源学报》2014年第5期653-660,共8页Plant Diversity

基　　金：四川省教育厅项目(12ZB142)

摘　　要：以葎草(Humulus scandens)为实验材料,在控制土壤水分的条件下探究干旱对雌雄异株植物开花物候和花器官形态的影响,结果表明:干旱胁迫将导致葎草雌雄种群花期提前,花期持续时间延长,雌花将比雄花提早开放;干旱胁迫下雄花的花序轴长、花序轴直径和花药粒径长均分别显著减小24.81%,29.07%和5.14%(P<0.001,P=0.003,P=0.024),花粉活力和花粉含量显著下降;干旱胁迫导致雌花的花序轴长、柱头长度和花序的平均花数量显著增大9.78%,70.62%和57.04%(P=0.039,P<0.001,P<0.001);干旱胁迫下种子粒径长、种子粒径宽、种子单粒重和种子千粒重分别显著下降12.12%、12.59%、43.43%和15.38%(显著度水平均为P<0.001);干旱胁迫下雌雄植株的地上部分生物量均显著降低(P=0.002,P=0.020),且雌株的生殖投入在干旱胁迫下显著高于雄株(P=0.049)。研究结果表明了葎草雌雄植株开花物候及花器官对干旱的响应明显不同。与雄株相比,雌株在干旱胁迫下增加了生物量向生殖器官的分配,从而最大程度地减轻胁迫对其繁殖能力的影响。In this paper, sex-specific differences in flowering phenology and floral morphology of Humulus scandens were tested using a pot experiment under water-controlled condition. Obvious differences between the male and female individuals were observed in response to different water regime. Drought stress induced H. scandens population to flower earlier and last longer. Compared with males, flowers of female opened earlier. Moreover, inflorescence axis length, inflorescence axis diameter and anther length in drought-stressed males were significantly reduced 24. 81%, 29. 07%, and 5. 14% （P〈0. 001, P= 0. 003, P= 0. 024）, respectively. Concomitantly, pollen quantity and the pollen vitality were also decreased significantly. In contrast, the inflorescence axis length, style length and average number of flowers per inflorescence in drought-stressed females were increased 9.78%, 70. 62%, and 57.04% （ P = 0. 039, P〈0. 001, P〈0. 001）, respectively. Furthermore, the seed length, and seed width, single-seed weight, and 1000-seed weight under drought stress were significantly reduced 12. 12%, 12. 59%, 43.43%, and 15. 38%, respectively （P〈0. 001 ）. On the other hand, compared with contrast, the aboveground biomass decreased significantly in both male and female H. scandens individuals under drought stress （P= 0. 002, P= 0. 020）. However, the reproductive investment of females was significantly higher than males under drought stress （P= 0. 049）. In a word, effects of drought stress on flowering phenology and floral organs are significantly different between two sexes. To alleviate the negative influences on reproductive ability caused by drought, females of H. scandens individuals may al- locate more biomass to reproductive organs than males under drought stress.

关 键 词：干旱 开花物候 花形态 雌雄差异 

分 类 号：Q945.78[生物学—植物学]