Báo cáo lâm nghiệp: Effect of soil temperature upon the root growth and mycorrhizal formation of white spruce (Picea glauca (Moench) Voss) seedlings grown in controlled environments

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Effect of soil temperature upon the root growth and mycorrhizal formation of white spruce (Picea glauca (Moench) Voss) seedlings grown in controlled environments...
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Báo cáo lâm nghiệp: "Effect of soil temperature upon the root growth and mycorrhizal formation of white spruce (Picea glauca (Moench) Voss) seedlings grown in controlled environments"Effect of soil temperature upon the root growthand mycorrhizal formation of white spruce(Picea glauca (Moench) Voss) seedlingsgrown in controlled environments D.P. LavenderL. HustedDepartment of Forest Sciences, University of British Columbia, Vancouver, Canada grown at 3 root zone temperatures: 5-8, 15-17Introduction 7 and 25-29°C in a growth cabinet programmed for 19-21°C air temperatures, 70-90% RH and an 18 h photoperiod. The root zone tem-The effects of root zone temperature and perature and inoculation treatments were facto-mycorrhizal formation on the shoot and 15 treatment combina- rially arranged give toroot morphology of white spruce seedlings tions.were examined in a controlled environ- Seedling height and caliper were measuredment. A companion study evaluated ef- at the initiation of treatment, 5 and 15 wk later.fects of root zone temperature upon root At each sample date, a subsample of seedlings was harvested to estimate needle, stem andgrowth at different stages of seedling root dry weight, length of long roots, short rootgrowth throughout the year. development and mycorrhizal formation. Mycor- rhizal formation was estimated by scanning the surface of the whole root plugs at 12-40x magnification and checking whole mounts at 500-1000x (Dan!ielson and Visser, 1984).Materials and Methods Treatment means for the 15 wk sample were compared by 2-way least squares analysis of covariance using SYSTAT. Initial caliper, the co- old dormant container-grown white spruce3 mo not with the variate, did interact significantly from a northern British Columbiaseedlings treatments (P>0.80).seed source were inoculated with: 1 ) Hebe-loma crustiliniforme, 2) Thelephora terrestris, 3) Populations of white spruce seedlings grownforest floor collected from a vigorous northern in 313 styroblocks under natural conditionsspruce plantation, 4) peat:vermiculite collected commencing in April were placed in controlledfrom mycorrhizal (mainly E-strain and MRA) environment facilities for 1 mo periods on thecontainer nursery stock, and 5) nothing (con- following dates: 21/9/87, 21/12/87, 16/5/88,trol). After inoculation, the seedlings were 18/7/88. Seedlings were dormant prior to eachtrials, but doubtless had different physiologies. interactions between inoculation and tem- maintained out-of-doors beforeSeedlings were seedling morphol- treatments on peraturethe first 2 trials; were stored at 2°C in darkness conducted using 3 classes of were ogyfor the period Dec 87-May 88, a common B.C. mycorrhizal formation: 1 ) no mycorrhizae,practice; and had recently completed the 2nd yr 2) mycorrhizae formed by T. terrestris andgrowth flush in July 88. The growth chambers 3) mycorrhizae formed by other fungalwere ...