Reactive shifts in the pattern of resource allocation in three Lolium species with different levels of persistency under clipping disturbance

Abstract

Persistency of plant growth is closely related to the manner of resource allocation; however, plants often shift the pattern of resource allocation depending on their growth condition. We examined how the plants with different levels of persistency change their resource allocation patterns in response to defoliation using three Lolium species: L. temulentum (annual); L. multiflorum (predominantly annual but occasionally overwinter); and L. perenne (perennial). We subjected the plants to clipping treatment by excising approximately 70% of the aboveground body parts of the plants from the three species, and compared the growth pattern of clipped plants with that of the intact controls. Lolium species with different persistency have developed different reaction norms for resource allocation to clipping treatment. After clipping, L. temulentum and L. multiflorum maintained the proportion of reproductive tillers and seed productivity resulting in an increase in the resource investment in the development of reproductive parts, which was compensated with the loss of allocation to the development of vegetative parts. Annual species, which can propagate themselves only through seed generation, possibly enhanced seed production to ensure regeneration under undesirable condition at the cost of vegetative growth. In contrast, L. perenne invested more resources in foliage development by reducing seed production in response to clipping treatment. Perennial plants that can endure adverse effects possibly allocate substantial portion of the resources to vegetative growth for ensuring survival. L. multiflorum showed similar regrowth habits with respect to the constant foliage and seed production per panicle as those of L. perenne, but differed from those of L. temulentum. This may be because the two former species have common ancestors.

Differential effects of anthropogenic edges and gaps on the reproduction of a forest‐dwelling plant: The role of plant reproductive effort and nectar robbing by bumblebees

“…Secondary responses to stress or disturbance, such as the changes in flower production in plants near forest edges or gaps, agree with previous studies (e.g. Aoyagi & Akimoto 2009) that attributed them to local increases in resources (e.g. light; Feinsinger et al .…”

Ground Cover Assessment of Perennial Ryegrass Using Digital Imaging

“…Good persistence indicates disease resistance and competitive ability (Aoyagi and Akimoto, 2009). Ground cover can vary between grass cultivars.…”

Impacts of grazing and mowing on reproductive behaviors of Stipa grandis and Stipa krylovii in a semi-arid area

“…Grazing and mowing, as common disturbances in grassland, usually affect the biomass distribution between plant growth and reproduction (Adler et al, 2001;Begay et al, 2011;Guo et al, 2011;N'Guessan and Hartnett, 2011;Kioko et al, 2012). This phenomenon is mainly due to changed plant growth conditions caused by grazing and mowing, which affect not only the morphology and phenology (Van Tienderen and van der Toorn, 1991;Franks et al 2007;Reisch and Poschlod, 2011) but also the resource al-location manner of plants (Aoyagi and Akimoto, 2009;Mao et al, 2012) of different ecological types. The way in which plants allocate their resources is one of the most important factors in determining the persistence of plant growth (Mulder and Ruess, 1998;Taisma and Herrera, 1998;Wilkins, 2002), and could also affect plant reproductive behavior.…”