| Abstract: | In a greenhouse trial, non-mycorrhizal and mycorrhizal plants of Sorghum bicolor were grown at three water regimes. The root length and root morphology of Sorghum bicolor was monitored in two soils during 34 days. From 29 days on, total root length of mycorrhizal sorghum was greater than of non-mycorrhizal sorghum in moderate and high water stress conditions. In soil A, at all water regimes a lower percentage of coarse roots and smaller root length per leaf area were found with mycorrhizal plants; in soil B, this was only the case in well watered conditions. In general, all root and water relation parameters were less affected by water stress when plants were mycorrhizal; this less sensitivity of mycorrhizal sorghum may increase the tolerance of the plant to drought. However, water relations of plants were indirectly enhanced by mycorrhiza via increased P uptake. |
