Mycorrhizal status of Scots pine Pinus sylvestris L. seedlings grown in watered and non-watered nursery condition

This study describes the effect of watering on the mycorrhizal development and growth of Scots pine seedlings in a bare root nursery. Seedlings of Scots pine, grown under nursery conditions on natural soil (loamy sand) and soil + litter, were subjected to two different watering regimes for five months. During this time, measurements of soil water potential were made. Seedlings grown in natural soil and subjected to drought conditions were of significantly greater shoot height and volume and they had one mycorrhizal morphotype more than watered seedlings. However, irrigated seedlings subjected to excessive watering possessed greater mycorrhizal colonization: 46% on natural soil and 72% on soil + litter, while non-irrigated seedlings had 36% and 67% levels of mycorrhizal colonization, respectively.