Data
Blocking was used to attempt to control for varying greenhouse effects. Since the seedlings were growing in separate pots, each seedling is considered an experimental unit. The predictor variables are the breeding class, and treatment groups. The responding variables were height, water use efficiency and stomatal conductance.
Figure 1. Boxplot examining the effect of treatment group (X-axis) organized by breeding class on mean stem height of seedlings. DNO= Drought and not inoculated, DO= drought and inoculated, WNO= well-watered and not inoculated, WO= well-watered and inoculated.
In Figure 1 we can see that for each of the four treatment groups, the elite seedlings were the tallest followed by the improved and then the unimproved. It doesn't appear from this figure that treatment had an overwhelming affect on seedling height, but the drought and inoculated group of seedlings did seem to be the shortest overall.
Figure 2. Boxplot examining the effect of treatment group (X-axis) organized by breeding class on mean water use efficiency of seedlings. DNO= Drought and not inoculated, DO= drought and inoculated, WNO= well-watered and not inoculated, WO= well-watered and inoculated.
It can be observed that in Figure 2 that the well-watered and not inoculated treatment group had the highest water use efficiency values, indicating that they were most effectively photosynthesizing. This makes sense, that treatment group should be the least stressed and putting the most effort into growth. This data does have more outliers than the height data, and some boxes may are not evenly distributed.
Figure 3. Boxplot examining the effect of treatment group (X-axis) organized by breeding class on mean stomatal conductance of seedlings. DNO= Drought and not inoculated, DO= drought and inoculated, WNO= well-watered and not inoculated, WO= well-watered and inoculated.
This boxplot (Figure 3) outlining the effect of treatment group and breeding class on stomatal conductance tells much the same story as Figures 1 and 2. The well-watered and not inoculated treatment group overall had the highest stomatal conductance, indicating that this group contained the happiest and healthiest trees. This makes sense, considering they were not being subjected to any environmental stressors.