营养生长期雌雄葎草表观性状对水分胁迫响应的性别差异

通过设置4个水分梯度,对营养生长期的葎草进行干旱胁迫处理,于性别可识别时,测定雌雄单株的根、茎、叶等构件数量性状、鲜重干重及占生物量比例等指标。结果表明,葎草通过显著缩短营养生长持续期应对水分胁迫,雄株比雌株对水分缺乏更加敏感;根首先,叶次之,茎第三对胁迫做出响应;根通过降低自身含水量满足茎、叶对水分的需要,同时茎叶通过减少叶片数与茎分枝数,缩小单叶面积与茎长度,降低单株对水分的消耗;雄株的叶总面积,茎分枝、长度与体积,根长与体积显著低于雌株;水分对各构件鲜重、干重均存在极显著影响,但性别间仅根系生物量存在显著差异;雄株的总生物量显著低于雌株,但性别对构件生物量分配比例无显著影响。通过减少营养生长投入,快速转入生殖生长应对水分胁迫,为葎草种群繁衍与扩展奠定基础。

Humulus scandens gender differences in response to water stress in the vegetative growth stage

Humulus scandens in the vegetative growth stage was treated with the drought stress of four water gradients. When the sex could be identified, some indicators of single male and female plants, including the quantitative traits of components (root, stem, leaves), fresh weight, hay weight, and the proportion of component to total biomass, were measured and analyzed. H. scandens responded to water stress by significantly shortening the duration of vegetative growth. Male plants were more sensitive to the lack of water than female plants. Response to water stress was in the order roots, leaves, and stems. Root moisture content was reduced to meet the needs of stems and leaves to water. Meanwhile, the plant reduced the consumption of water by reducing the number of leaves and branches and by narrowing leaf area and stem length. These indicators (including total leaf area, branch, length and volume of stem, length and volume of root) were lower on male than on female plants. Water had a highly significant effect on fresh weight and hay weight of each component. Sex significantly affected only the biomass of roots. The total biomass of male plants was significant lower than that of female plants, but there was no difference between them in the distribution of each component of the biomass. H. scandens responded to water stress by reducing investment in vegetative growth and quickly switching into reproductive growth, which laid the foundation for reproduction and expansion of the population.