Wearing glasses and a brown shirt, Mr. Almstead is a tree doctor who speaks with unshakable vim on the subjects of corrective pruning, deep-root fertilization, infestation inoculations and other procedures to save the life of a tree.
Our study of biomass partitioning in relation to varying nutritional levels in loblolly pine supports the previous hypothesis, proposed by Linder and Axelson [ 1], that the reduced production of fine roots under fertilization results in the increase of stem production through the optimal use of energy.
In the study, we integrate the conceptual theory of phenotypic plasticity into the test of the hypothesis that the reduced production of fine roots under high fertilization can increase stem productivity in loblolly pine.
Stimulation of shoot growth relative to root growth by fertilization could make these forests more vulnerable to windthrow and waves associated with intense tropical storms and tsunamis [45].
For "mesic" families, the plasticity of foliage biomass partitioning did not give rise to a change in stem biomass (p y ←1 = -0.09), whereas the plasticity of fine-root biomass partitioning, i.e., decreased partitioning of biomass to fine roots under higher fertilization, had a significant impact on the corresponding increase of stem biomass (p y ←2 = - 0.99, Fig. 2A).
Contrary to expectations, fertilization decreased root starch reserves although it increased basal area increment; thinning had no effect on root carbohydrates.
Previous studies of fertilization on root biomass have reported similar findings to our study.
Fertilization increased root nitrogen concentrations (RNCs) and RD and decreased SRL and root carbon concentrations (RCCs) [see Supporting Information Fig. S1M Q ] (Table 3).
Fig. 2 Effect of N fertilization on a cumulative root length, b mean root diameter, c specific root area, and d specific root length for each root order (n = 5 pots).
Microbial revitalization using plant growth promoters had been achieved through direct and indirect approaches like bio-fertilization, invigorating root growth, rhizoremediation, disease resistance etc. Although, there are a wide variety of PGPR and its allies, their role and usages for sustainable agriculture remains controversial and restricted.
These results indicate that both NSP2 and MIR171h show a complex regulation of their transcription, which depends on the symbiotic status of the roots and the nutrient fertilization regime.
