Density-dependent habitat selection in plants |
| |
Authors: | M Gersani Z Abramsky O Falik |
| |
Institution: | (1) Department of Life Science, Ben-Gurion University of the Negev, Beer Sheva, 84105, Israel |
| |
Abstract: | Pea plants exhibit density-dependent habitat selection as they grow. We split the root of a young pea (Pisum sativum L.) so
that half grew in one pot and half in an adjacent pot. The rest of the plant remained intact. This is a ‘fence-sitter plant’.
Each root-half was exposed either to no competition in its pot or to competitor plants sharing its pot. There were one, two,
three or five competitor plants. The total root biomass and the fitness (= dry weight of fruit) of the fence-sitter decreased
only slightly and insignificantly in response to increased density of the competitor plants. The fitness of the competing
plants decreased with density. The fence-sitter shifted its root system from the pot with competition to that free of competition
in proportion to the number of competitors. The fence-sitter apparently invested in each of its two roots so that the ratio
between the roots was similar to the ratio between the resources in the pots. This result is analogous to the habitat-matching
rule of the ideal free distribution of populations (Fretwell, 1972). We suggest that plants invest in each of their roots
until the uptake rate per unit root biomass is equal for all roots.
This revised version was published online in July 2006 with corrections to the Cover Date. |
| |
Keywords: | competition habitat selection phenotypic plasticity split root |
本文献已被 SpringerLink 等数据库收录! |