102
Phytotechnology with Biomass Production
Biomass yields increased year by year, but D 1 –D 3 did not differ significantly from one another in any year. Within treatments yield estimates
varied ±20%. “From the center of each plot, six randomly selected plants
were collected”. Yields in year 3 were ~9 Mg ha −1 for the control D 0 and ~15
Mg ha −1 for the three treatments with sludge. This represents a positive use
for a marginal land. The authors estimated that it might take 7–10 years to
become profitable as a crop, because of establishment and harvest costs.
Overall, there is good evidence that geographic location is very important
to potential M. × giganteus yields, as reviewed by Heaton et al. (2010), independent of fertility of soil, addition of fertilizers, and other nutrient amendments.
Latitude influences time of flowering and yield. Higher latitudes delay flowering. Rainfall patterns (timing and amounts) and temperature regimes determine
the regions where rain-fed crops can be successfully grown for maximum production. Continental vs oceanic climates markedly affect stability of yields. For
the U.S. there are adaptability maps showing likely zones of relative yield, based
on models of M. × giganteus growth patterns. There have been enough regional
studies to indicate that in some locations alternatives other than M. × giganteus
are more productive at least for a few years of study (Smith et al., 2015b). There
have not been sufficient long-term studies to say how they would fare over the
course of decades. Similar maps have also been developed with alternate bioenergy crops including maize, switchgrass, sorghum, and select sugarcane CVs
identified as “Energy Cane” (Matsuoka et al., 2014). For total biomass production
in the south of US, M. × giganteus cannot compete with Energy Cane.
Very sophisticated models of growth patterns for M. × giganteus in Europe
have been developed. Early examples are discussed in Heaton et al. (2010).
These have good predictive values when key features including latitude,
hours of light, water, and temperature are input to the models.
5.7 Role of Plant Growth Regulators in
Production of M. × giganteus
Plant growth regulators (PGRs, earlier term “phytohormones”) are a group
of treatment substances used for enhancing plant growth (Procházka &
Šebánek, 1997). There are five main classical groups of natural PGRs: auxins, cytokinins, gibberellins, ethylene, abscisic acid; in addition, there is a
class of “new plant hormones” formed by brassinosteroids, salicylic acid, jasmonates, and strigolactones. For each class there are substances chemically
or biologically synthesized and used as mimics or inhibitors (agonists and
antagonists in biochemical terminology). Also, oligosaccharides, systemin,
polyamines, reactive oxygen species, and reactive nitrogen species including
nitric oxide possess activities similar to those of plant hormones in various
Phytotechnology with Biomass Production
Biomass yields increased year by year, but D 1 –D 3 did not differ significantly from one another in any year. Within treatments yield estimates
varied ±20%. “From the center of each plot, six randomly selected plants
were collected”. Yields in year 3 were ~9 Mg ha −1 for the control D 0 and ~15
Mg ha −1 for the three treatments with sludge. This represents a positive use
for a marginal land. The authors estimated that it might take 7–10 years to
become profitable as a crop, because of establishment and harvest costs.
Overall, there is good evidence that geographic location is very important
to potential M. × giganteus yields, as reviewed by Heaton et al. (2010), independent of fertility of soil, addition of fertilizers, and other nutrient amendments.
Latitude influences time of flowering and yield. Higher latitudes delay flowering. Rainfall patterns (timing and amounts) and temperature regimes determine
the regions where rain-fed crops can be successfully grown for maximum production. Continental vs oceanic climates markedly affect stability of yields. For
the U.S. there are adaptability maps showing likely zones of relative yield, based
on models of M. × giganteus growth patterns. There have been enough regional
studies to indicate that in some locations alternatives other than M. × giganteus
are more productive at least for a few years of study (Smith et al., 2015b). There
have not been sufficient long-term studies to say how they would fare over the
course of decades. Similar maps have also been developed with alternate bioenergy crops including maize, switchgrass, sorghum, and select sugarcane CVs
identified as “Energy Cane” (Matsuoka et al., 2014). For total biomass production
in the south of US, M. × giganteus cannot compete with Energy Cane.
Very sophisticated models of growth patterns for M. × giganteus in Europe
have been developed. Early examples are discussed in Heaton et al. (2010).
These have good predictive values when key features including latitude,
hours of light, water, and temperature are input to the models.
5.7 Role of Plant Growth Regulators in
Production of M. × giganteus
Plant growth regulators (PGRs, earlier term “phytohormones”) are a group
of treatment substances used for enhancing plant growth (Procházka &
Šebánek, 1997). There are five main classical groups of natural PGRs: auxins, cytokinins, gibberellins, ethylene, abscisic acid; in addition, there is a
class of “new plant hormones” formed by brassinosteroids, salicylic acid, jasmonates, and strigolactones. For each class there are substances chemically
or biologically synthesized and used as mimics or inhibitors (agonists and
antagonists in biochemical terminology). Also, oligosaccharides, systemin,
polyamines, reactive oxygen species, and reactive nitrogen species including
nitric oxide possess activities similar to those of plant hormones in various