10
2.4 Microbes Improve Agricultural Production
and Nutritional Quality
Several instances of harnessing the useful interactions between host plant and
microorganisms explicitly indicate that agricultural yield could be enhanced considering nutritional quality and biofortification attributes (Rana et al. 2012; Anupama
et al. 2015; Dubey et al. 2015, 2016b; Singh et al. 2018). Abiotic stresses are the key
components in reducing crop production. However, the strength of these stresses
changes with different soil and plant factors (Nadeem et al. 2014). Some adverse
impacts of these stresses on the plants include nutritional and hormonal imbalance,
and physiological and metabolic disorders such as epinasty, abscission, senescence,
and susceptibility to the diseases (Nadeem et al. 2014). Most of the yield parameters
and nutritional attributes are affected by stress conditions, which further affect
numerous physiological and biochemical processes. Among these processes,
N-fixation is one of the important processes that are susceptible to stress conditions.
Apart from this, biosynthesis of metabolites such as amino acids, vitamins, phytohormones, and/or nutrient solubilization and mineralization processes are also
prone to adverse conditions (Nadeem et al. 2014).
Research contextualizing to overcome the stresses and, hence, improve the production and the nutritional quality of the crop plants has been performed (Krey et al.
2013; Anupama et al. 2015). The yield of a wheat crop was enhanced with the inoculation of different PGPR such as cyanobacterial strains Anabaena sp., Calothrix
sp., and Anabaena sp. and Providencia sp. (PW5) (Rana et al. 2012). Enhanced
grain production with about 4.77, 4.87, and 4.66 t/ha with the combinations of different strains, that is, PW5, CW1 + PW5, and CW1 + CW2 + CW3, respectively.
However, grain yield in absolute control was 4.18 t/ha. Further, the biomass yield
was 15.33, 13.76, 13.56, and 14.94 t/ha with the respective combination of strains
whereas the biomass yields in the absolute control were about 14.15 t/ha. Similarly,
the harvest index was enhanced at 34.75%, 35.97%, and 31.20% by inoculation
with the respective combinations. The nutritional component of wheat-like protein
level and vital micronutrients such as copper, iron, zinc, and manganese was
enhanced by inoculation of PW5 (Rana et al. 2012). An increase of 18.6% in protein
level was observed in Providencia sp. (PW5) treatment supplemented with
N60P60K60 in comparison to the control with N60P60K60 fertilizer only. The concentration of Fe was drastically enhanced in the wheat grains following inoculation
of combinations of CW1, PW5, CW1 + PW5, or CW1 + CW2 + CW3, with the
basal dose of N60P60K60. The concentration of Fe was 136.93, 271.93, 206.13,
and 129.40 mg/kg, respectively; however, that in the control was 67.73 mg/kg.
Similarly, the concentration of Zn was 36.27, 41.73, 39.80, and 37.60 mg/kg,
respectively, whereas the control was 31.60 mg/kg. The level of Mn was about
38.13, 53.40, 34.33, and 33.40 mg/kg, respectively, as compared to that of the control, which was 22.93 mg/kg. The level of Cu was 41.93, 99.00, 81.60, and 37.53 mg/
kg, respectively, while that of the control was 33.13 mg/kg (Rana et al. 2012).
Biofortification of Zn in wheat was compared with the control when inoculated with
2 Belowground Microbial Communities: Key Players for Soil and Environmental…
2.4 Microbes Improve Agricultural Production
and Nutritional Quality
Several instances of harnessing the useful interactions between host plant and
microorganisms explicitly indicate that agricultural yield could be enhanced considering nutritional quality and biofortification attributes (Rana et al. 2012; Anupama
et al. 2015; Dubey et al. 2015, 2016b; Singh et al. 2018). Abiotic stresses are the key
components in reducing crop production. However, the strength of these stresses
changes with different soil and plant factors (Nadeem et al. 2014). Some adverse
impacts of these stresses on the plants include nutritional and hormonal imbalance,
and physiological and metabolic disorders such as epinasty, abscission, senescence,
and susceptibility to the diseases (Nadeem et al. 2014). Most of the yield parameters
and nutritional attributes are affected by stress conditions, which further affect
numerous physiological and biochemical processes. Among these processes,
N-fixation is one of the important processes that are susceptible to stress conditions.
Apart from this, biosynthesis of metabolites such as amino acids, vitamins, phytohormones, and/or nutrient solubilization and mineralization processes are also
prone to adverse conditions (Nadeem et al. 2014).
Research contextualizing to overcome the stresses and, hence, improve the production and the nutritional quality of the crop plants has been performed (Krey et al.
2013; Anupama et al. 2015). The yield of a wheat crop was enhanced with the inoculation of different PGPR such as cyanobacterial strains Anabaena sp., Calothrix
sp., and Anabaena sp. and Providencia sp. (PW5) (Rana et al. 2012). Enhanced
grain production with about 4.77, 4.87, and 4.66 t/ha with the combinations of different strains, that is, PW5, CW1 + PW5, and CW1 + CW2 + CW3, respectively.
However, grain yield in absolute control was 4.18 t/ha. Further, the biomass yield
was 15.33, 13.76, 13.56, and 14.94 t/ha with the respective combination of strains
whereas the biomass yields in the absolute control were about 14.15 t/ha. Similarly,
the harvest index was enhanced at 34.75%, 35.97%, and 31.20% by inoculation
with the respective combinations. The nutritional component of wheat-like protein
level and vital micronutrients such as copper, iron, zinc, and manganese was
enhanced by inoculation of PW5 (Rana et al. 2012). An increase of 18.6% in protein
level was observed in Providencia sp. (PW5) treatment supplemented with
N60P60K60 in comparison to the control with N60P60K60 fertilizer only. The concentration of Fe was drastically enhanced in the wheat grains following inoculation
of combinations of CW1, PW5, CW1 + PW5, or CW1 + CW2 + CW3, with the
basal dose of N60P60K60. The concentration of Fe was 136.93, 271.93, 206.13,
and 129.40 mg/kg, respectively; however, that in the control was 67.73 mg/kg.
Similarly, the concentration of Zn was 36.27, 41.73, 39.80, and 37.60 mg/kg,
respectively, whereas the control was 31.60 mg/kg. The level of Mn was about
38.13, 53.40, 34.33, and 33.40 mg/kg, respectively, as compared to that of the control, which was 22.93 mg/kg. The level of Cu was 41.93, 99.00, 81.60, and 37.53 mg/
kg, respectively, while that of the control was 33.13 mg/kg (Rana et al. 2012).
Biofortification of Zn in wheat was compared with the control when inoculated with
2 Belowground Microbial Communities: Key Players for Soil and Environmental…