Effects of different nutrient sources on plasticity of reproductive strategies in a monoecious species, Sagittaria graminea (Alismataceae)

Abstract

Varied nutrient sources can influence the plasticity of reproductive strategies in monoecious species differently. We examined the plasticity of sexual and clonal reproductive components in distinct nutrient sources in a monoecious species, Sagittaria graminea Michx. The results showed that for aboveground reproductive components, in rich-phosphorus and low-nitrogen conditions, the species produced more male flowers, whereas female flowers did not significantly increase in number compared to low-phosphorus and low-nitrogen conditions (control). In richnitrogen and low-phosphorus conditions, the species produced more flowers, particularly female, and more seeds, compared to the control conditions. In the rich-nitrogen and rich-phosphorus conditions, plants increased male flowers, female flowers, total flower number, synchronously, as well as seed production. For the belowground reproductive components, in the rich-phosphorus conditions, the plants produced bigger corms than in the richnitrogen and control conditions, which further enhanced their competitiveness against companion species. In richnitrogen conditions, the plants produced more medium and small corms, and relatively more and longer stolons, which were useful in expansion and invasion of more space. Furthermore, the species displayed trade-off relationships between the aboveground and belowground reproductive components in unbalanced nutrient conditions (add-N or add-P). However, in low nutrient levels (control) or in nutrient abundant (add-N þ P) conditions, there were no significant trade-off relationships between the aboveground and belowground reproductive components, based on quantities.

The contribution of carbon budget to masting intervals in Veratrum album populations inhabiting different elevations

“…Thus, in lowland populations that suffer from severe pollen limitations (Ito and Kudo, 2022), male‐biased resource allocation may be beneficial for pollination success. Furthermore, male‐biased flower production may contribute to a decrease in the total cost of reproduction (Dorken and Barrett, 2004; Han et al, 2011; Zhang et al, 2014). Because the lowland populations had smaller carbon fixation than the alpine populations, they may invest more resources in male‐flower production (Figure 6B).…”

Irrigation and Nitrogen Application Promote Population Density through Altered Bud Bank Size and Components in Leymus chinensis

“…The axillary shoot buds originate from the spring tiller base and grow close to the parent shoots to obtain more nutrients, and compared to the rhizome buds, they have a higher survival rate and rapid output ability [13,14,17,24]. Irrigation improves the nitrogen uptake and utilization rate of plants, and preferentially promotes axillary shoot bud formation and output [23,25,37]. In the present work, a proportion of the rhizome buds formed in spring developed into rhizomes, which improved the rhizome length and number to ensure access to limited soil resources.…”

“…For example, rhizome buds are more susceptible to changes in soil moisture, and higher soil moisture produces more rhizome buds [5,21]. Usually, increases in moderate soil moisture and nitrogen can promote the production of rhizomes and the output of axillary shoot buds, changing the size of the bud bank [22][23][24][25]. Rhizome traits such as length and number can also directly affect the number of buds growing on the rhizomes [5,11], ultimately increasing population density [25][26][27][28].…”

“…Usually, increases in moderate soil moisture and nitrogen can promote the production of rhizomes and the output of axillary shoot buds, changing the size of the bud bank [22][23][24][25]. Rhizome traits such as length and number can also directly affect the number of buds growing on the rhizomes [5,11], ultimately increasing population density [25][26][27][28]. However, rhizomatous clonal plants promote the output of axillary shoot buds at high nitrogen levels and inhibited the production of rhizomes and rhizome buds, causing changes in their growth strategies.…”

Altitudinal variation in flowering area and position and their ecological significances of an alpine cushion <i>Arenaria polytrichoides,</i> a gynodioecious herb

“…随着海拔逐渐上升, 环境条件变得更加严酷, 如: 海拔每上升100 m, 气温约下降0.6 ℃, 气压下 降8-9 hPa (Körner, 2003), 土壤养分含量也随之减 少(曹舰艇等, 2019)。面对高海拔地区低温、土壤养 分贫瘠等恶劣环境因子, 高山植物在长期的进化过 程中形成了丰富多样的特化适应性状或进化策略 (Sun et al, 2014;杨扬等, 2019), 种类丰富的植物多 样性对维持高山生态系统的稳定性起到了关键作用 (Hooper et al, 2005)。 滇西北处于横断山高山植物多 样性中心区域 (郭辉军和龙春林, 1998;Zhang et al, 2015)。长期以来, 青藏高原及横断山高海拔地区植 物对极端环境因子的适应机制, 备受植物学家和生 态学家的关注, 相关研究的深入开展, 加深了对该 地区植物多样性形成及其进化适应机制的认识 (Sun et al, 2014; 杨扬等, 2019)。 温度、资源(包括土壤养分、降水资源及太阳辐 射量等)是限制高山植物生长与繁殖的关键因素 (Bloom et al, 1985;Chen et al, 2017b)。为了应对高 海拔地区贫瘠的土壤条件, 植物在自身资源获取及 分配方面进化出了众多与环境相适应的资源分配策 略。其中, 繁殖分配(即植物分配到繁殖器官的资源 量)是植物适合度的关键表现 (Bazzaz et al, 1987;Weiner, 1988;Hartnett, 1990;Vega et al, 2000)。研究 表明, 植物繁殖分配同时受到众多非生物与生物因 子的控制 (Reekie & Bazzaz, 2005; 张婵等, 2020)。 非 生物因子方面, 温度、水分、土壤营养等对植物的 繁殖分配起着重要作用 (Reekie & Bazzaz, 2005;Zhang et al, 2014)。而在生物因子方面, 种间竞争、 传粉者特性以及植物自身性系统特征 (Ashman, 1994;Case & Ashman, 2005;Brzyski et al, 2014;Chen et al, 2017aChen et al, , 2017b (Ashman, 1994;Chen et al, 2017aChen et al, , 2017b, 并且这 种分配模式受到环境因子的强烈影响 (Chen et al, 2017b) "护理作用", 可提高和维持生态系统中物种多样性 (Butterfield et al, 2013;Cavieres et al, 2014;Chen et al, 2015aChen et al, , 2015bChen et al, , 2019 (Yang et al, 2010(Yang et al, , 2017Chen et al, 2015aChen et al, , 2019。然而, 团状福禄草种群的更新却受到 种间竞争的强烈影响 (Chen et al, 2020)。研究者在 近十年内对团状福禄草做了深入调查与研究 …”