Intra‐ and inter‐sexual competition of Populus cathayana under different watering regimes

Abstract

Summary1. Previous studies have demonstrated that poplar is sexually dimorphic in its responses to environmental stresses and provided evidence of sex-related differences in protein composition, gene transcription and morphological and physiological processes. However, sexual competition of poplar has not yet been studied. 2. We employed Populus cathayana males and females as a model to investigate intra-and intersexual competition under well-watered condition and drought stress. 3. Our results indicated that competition significantly affected sexual dimorphism of P. cathayana under different watering regimes. Sexual competition was environment-dependent and modified by drought. In females, drought intensified the negative effect of intrasexual competition. Similar resource utilization patterns of females may aggravate pressure for resources under drought stress. Under intersexual competition, females showed a greater competitive ability than males under well-watered condition, while males showed a slight competitive advantage under drought stress. Intersexual competition seems to alleviate the sexual dimorphism of P. cathayana in response to drought stress, as females increase fitness and males decrease fitness compared with intrasexual competition. 4. Sexual dimorphism in resource utilization patterns and niche segregation may contribute to sexual competition in a given environment. Sexual competition was found to affect competitive ability and fitness of both sexes, which may cause spatial segregation of sexes in P. cathyana populations.

Continuous planting under a high density enhances the competition for nutrients among young Cunninghamia lanceolata saplings

“…Plant density greatly affects plantation productivity. A high planting density can reduce biomass production, decrease the photosynthetic efficiency, and change the resource use efficiency (Mediavilla et al 2001;Wang et al 2005;Dybzinski et al 2013;Chen et al 2014). Although these differences are species specific and vary with the developmental stage, a decrease in the photosynthetic rate frequently occurs in many plants, especially in saplings.…”

Ecophysiological responses of two dominant subalpine tree species Betula albo-sinensis and Abies faxoniana to intra- and interspecific competition under elevated temperature

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Populus deltoides females are more selective in nitrogen assimilation than males under different nitrogen forms supply

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