Lectures on species interactions and competition

Fischer et al. (2002) Results
• Net photosynthetic rates of kochia were
greater at photosynthetically active
radiation (PAR) values > 400 μmol m -2 s -1 .
Growth and CO 2 exchange rates varied
among four different kochia accessions,
but growth of all accessions was reduced
by shade.
• Results suggest that a leafy, cold-tolerant
crop or cultivar, grown early in the season
to produce necessary ground cover,
should provide opportunity to suppress
kochia.
Fig. 4 (a) Net CO 2
assimilation rates and (b) photosynthetic water use
efficiency of barley (open circles), wheat (solid circles), and kochia
(solid triangles), as affected by levels of photosynthetically active
radiation (PAR), when grown under moisture stress at 23/19°C
day/night.
(Fisher et al. 2000.)