Nitrogen addition and rhizome severing modify clonal growth and reproductive modes of Leymus chinensis population

Abstract

We examined the effects of N addition and rhizome severing on sexual and clonal reproduction and their trade-off in a rhizome clonal grass, Leymus chinensis (Trin.) Tzvel. We discovered that N addition not only greatly increased the quantity and biomass of Leymus chinensis ramets, but also promoted ramet production by increasing the tillers of the plant, while abated the other alternative clonal propagation strategy of rhizome elongation. However, N addition did not affect the rhizome biomass and it significantly reduced the flowering probability, the individual seed mass, and the seed number. Rhizome severing did not markedly affect the quantity and the weight of ramets, the individual seed mass or the seed number, but greatly decreased the rhizome biomass. A significantly negative relation was found between sexual and clonal propagation in Leymus chinensis population upon N addition. We showed that the nutrient availability can modify the sexual versus clonal reproductive trade-off and the clonal propagation strategy. Intense ramet production characteristics of clonal growth will largely affect the sexual reproductive capacity and intensify intraclonal competition, thereby influencing their genetic diversity, spatial colonizing ability and life history strategy.

Trade-offs among growth, clonal, and sexual reproduction in an invasive plant Spartina alterniflora responding to inundation and clonal integration

“…Our results indicated that once the clonal production of S. alterniflora associated with short-distance spread was inhibited by the surrounding physical environmental stress, the sexual production would be promoted to benefit long-distance dispersal, which would increase the probability to occupy more suitable habitats. However, similar to an earlier study in a rhizome clonal grass Leymus chinensis (Bai et al, 2009), we observed that rhizome fragmentation did not affect the reproductive strategy.…”

Nitrogen acquisition strategies used by Leymus chinensis and Stipa grandis in temperate steppes

“…In the temperate semi-arid steppes of North China, the Leymus chinensis community and Stipa grandis community are two generally known steppes widely distributed on the Mongolian plateau (Li 1988). L. chinensis, possessing long strong rhizomes and vigorous vegetative propagation, gives rise to extensively spreading clones and often forms monodominant stands (Bai et al 2009). S. grandis, however, is a type of perennial tussock grass completely different from L. chinensis (Zhao et al 2004).…”

Effects of salinity and clonal integration on growth and sexual reproduction of the invasive grass Spartina alterniflora

“…The mechanisms that allow S. alterniflora to adapt to high salinity conditions, such as germination, growth, reproduction, morphology and physiology, have been well documented (Brown and Pezeshki, 2007;Brown et al, 2006;Hester et al, 2001;Vasquez et al, 2006;Wang et al, 2010). Since resources for metabolism and biomass gain are limited, increasing resource allocation to one function may reduce that to other functions (Bai et al, 2009;Liu et al, 2009). Reduced growth in response to increased sexual production has been known for many species (Snow and Whigham, 1989;Stark et al, 2009;Thiele et al, 2009).…”